update to version v0.3.0

46 setter functions being called at startup when loading json file

.coveragerc

@@ -2,5 +2,3 @@
 exclude_lines = 
     pragma: no cover
     if TYPE_CHECKING:
-omit =
-    src/pydase/utils/logging.py

.flake8

@@ -1,8 +1,8 @@
 [flake8]
-ignore = E501,W503,FS003,F403,F405,E203,UNT001
+ignore = E501,W503,FS003,F403,F405,E203
 include = src
 max-line-length = 88
 max-doc-length = 88
 max-complexity = 7
-max-expression-complexity = 5.5
+max-expression-complexity = 7
 use_class_attributes_order_strict_mode=True

.github/workflows/publish-to-pypi.yaml

@@ -86,26 +86,26 @@ jobs:
         '${{ github.ref_name }}' dist/**
         --repo '${{ github.repository }}'
 
-  publish-to-testpypi:
-    name: Publish Python 🐍 distribution 📦 to TestPyPI
-    needs:
-    - build
-    runs-on: ubuntu-latest
-
-    environment:
-      name: testpypi
-      url: https://test.pypi.org/p/pydase
-
-    permissions:
-      id-token: write  # IMPORTANT: mandatory for trusted publishing
-
-    steps:
-    - name: Download all the dists
-      uses: actions/download-artifact@v3
-      with:
-        name: python-package-distributions
-        path: dist/
-    - name: Publish distribution 📦 to TestPyPI
-      uses: pypa/gh-action-pypi-publish@release/v1
-      with:
-        repository-url: https://test.pypi.org/legacy/
+  # publish-to-testpypi:
+  #   name: Publish Python 🐍 distribution 📦 to TestPyPI
+  #   needs:
+  #   - build
+  #   runs-on: ubuntu-latest
+  #
+  #   environment:
+  #     name: testpypi
+  #     url: https://test.pypi.org/p/pydase
+  #
+  #   permissions:
+  #     id-token: write  # IMPORTANT: mandatory for trusted publishing
+  #
+  #   steps:
+  #   - name: Download all the dists
+  #     uses: actions/download-artifact@v3
+  #     with:
+  #       name: python-package-distributions
+  #       path: dist/
+  #   - name: Publish distribution 📦 to TestPyPI
+  #     uses: pypa/gh-action-pypi-publish@release/v1
+  #     with:
+  #       repository-url: https://test.pypi.org/legacy/

.github/workflows/python-package.yml

@@ -5,36 +5,37 @@ name: Python package
 
 on:
   push:
-    branches: ['main']
+    branches: [ "main" ]
   pull_request:
-    branches: ['main']
+    branches: [ "main" ]
 
 jobs:
   build:
+
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
-        python-version: ['3.9', '3.10', '3.11']
+        python-version: ["3.10", "3.11"]
 
     steps:
-      - uses: actions/checkout@v3
-      - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v3
-        with:
-          python-version: ${{ matrix.python-version }}
-      - name: Install dependencies
-        run: |
-          python -m pip install --upgrade pip
-          python -m pip install poetry
-          poetry install
-      - name: Lint with flake8
-        run: |
-          # stop the build if there are Python syntax errors or undefined names
-          poetry run flake8 src/pydase --count --show-source --statistics
-      - name: Test with pytest
-        run: |
-          poetry run pytest
-      - name: Test with pyright
-        run: |
-          poetry run pyright src/pydase
+    - uses: actions/checkout@v3
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v3
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install poetry
+        poetry install
+    - name: Lint with flake8
+      run: |
+        # stop the build if there are Python syntax errors or undefined names
+        poetry run flake8 src/pydase --count --show-source --statistics
+    - name: Test with pytest
+      run: |
+        poetry run pytest
+    - name: Test with pyright
+      run: |
+        poetry run pyright src/pydase

.readthedocs.yaml

@@ -0,0 +1,21 @@
+# Read the Docs configuration file for MkDocs projects
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+# Required
+version: 2
+
+# Set the version of Python and other tools you might need
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3.11"
+
+mkdocs:
+  configuration: mkdocs.yml
+
+# Optionally declare the Python requirements required to build your docs
+python:
+  install:
+  - method: pip
+    path: .
+  - requirements: docs/requirements.txt

.vscode/launch.json

@@ -1,7 +1,4 @@
 {
-    // Use IntelliSense to learn about possible attributes.
-    // Hover to view descriptions of existing attributes.
-    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
     "version": "0.2.0",
     "configurations": [
         {
@@ -19,7 +16,7 @@
             "type": "python",
             "request": "launch",
             "module": "bar",
-            "justMyCode": true,
+            "justMyCode": false,
             "env": {
                 "ENVIRONMENT": "development"
             }
@@ -29,7 +26,7 @@
             "request": "launch",
             "name": "react: firefox",
             "url": "http://localhost:3000",
-            "webRoot": "${workspaceFolder}/frontend",
+            "webRoot": "${workspaceFolder}/frontend"
         }
     ]
-}
+}

README.md

@@ -1,5 +1,8 @@
 # pydase (Python Data Service) <!-- omit from toc -->
 
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
+[![Documentation Status](https://readthedocs.org/projects/pydase/badge/?version=latest)](https://pydase.readthedocs.io/en/latest/?badge=latest)
+
 `pydase` is a Python library for creating data service servers with integrated web and RPC servers. It's designed to handle the management of data structures, automated tasks, and callbacks, and provides built-in functionality for serving data over different protocols.
 
 - [Features](#features)
@@ -9,9 +12,20 @@
   - [Running the Server](#running-the-server)
   - [Accessing the Web Interface](#accessing-the-web-interface)
   - [Connecting to the Service using rpyc](#connecting-to-the-service-using-rpyc)
+- [Understanding the Component System](#understanding-the-component-system)
+  - [Built-in Type and Enum Components](#built-in-type-and-enum-components)
+  - [Method Components](#method-components)
+  - [DataService Instances (Nested Classes)](#dataservice-instances-nested-classes)
+  - [Custom Components (`pydase.components`)](#custom-components-pydasecomponents)
+    - [`Image`](#image)
+    - [`NumberSlider`](#numberslider)
+    - [`ColouredEnum`](#colouredenum)
+    - [Extending with New Components](#extending-with-new-components)
+- [Customizing Web Interface Style](#customizing-web-interface-style)
 - [Understanding Service Persistence](#understanding-service-persistence)
 - [Understanding Tasks in pydase](#understanding-tasks-in-pydase)
 - [Understanding Units in pydase](#understanding-units-in-pydase)
+- [Changing the Log Level](#changing-the-log-level)
 - [Documentation](#documentation)
 - [Contributing](#contributing)
 - [License](#license)
@@ -19,30 +33,39 @@
 ## Features
 
 <!-- no toc -->
-* [Integrated web interface for interactive access and control of your data service](#accessing-the-web-interface)
-* [Support for `rpyc` connections, allowing for programmatic control and interaction with your service](#connecting-to-the-service-using-rpyc)
-* [Saving and restoring the service state for service persistence](#understanding-service-persistence)
-* [Automated task management with built-in start/stop controls and optional autostart](#understanding-tasks-in-pydase)
-* [Support for units](#understanding-units-in-pydase)
-* Event-based callback functionality for real-time updates
-* Support for additional servers for specific use-cases
+- [Simple data service definition through class-based interface](#defining-a-dataService)
+- [Integrated web interface for interactive access and control of your data service](#accessing-the-web-interface)
+- [Support for `rpyc` connections, allowing for programmatic control and interaction with your service](#connecting-to-the-service-using-rpyc)
+- [Component system bridging Python backend with frontend visual representation](#understanding-the-component-system)
+- [Customizable styling for the web interface through user-defined CSS](#customizing-web-interface-style)
+- [Saving and restoring the service state for service persistence](#understanding-service-persistence)
+- [Automated task management with built-in start/stop controls and optional autostart](#understanding-tasks-in-pydase)
+- [Support for units](#understanding-units-in-pydase)
+<!-- * Event-based callback functionality for real-time updates
+- Support for additional servers for specific use-cases -->
 
 ## Installation
 
+<!--installation-start-->
+
 Install pydase using [`poetry`](https://python-poetry.org/):
 
 ```bash
-poetry add git+https://github.com/tiqi-group/pydase.git
+poetry add pydase
 ```
 
 or `pip`:
 
 ```bash
-pip install git+https://github.com/tiqi-group/pydase.git
+pip install pydase
 ```
 
+<!--installation-end-->
+
 ## Usage
 
+<!--usage-start-->
+
 Using `pydase` involves three main steps: defining a `DataService` subclass, running the server, and then connecting to the service either programmatically using `rpyc` or through the web interface.
 
 ### Defining a DataService
@@ -116,7 +139,7 @@ if __name__ == "__main__":
     Server(service).run()
 ```
 
-This will start the server, making your Device service accessible via RPC and a web server at http://localhost:8001.
+This will start the server, making your Device service accessible via RPC and a web server at [http://localhost:8001](http://localhost:8001).
 
 ### Accessing the Web Interface
 
@@ -144,11 +167,220 @@ print(client.voltage)  # prints 5.0
 
 In this example, replace `<ip_addr>` with the IP address of the machine where the service is running. After establishing a connection, you can interact with the service attributes as if they were local attributes.
 
+<!--usage-end-->
+
+## Understanding the Component System
+
+<!-- Component User Guide Start -->
+
+In `pydase`, components are fundamental building blocks that bridge the Python backend logic with frontend visual representation and interactions. This system can be understood based on the following categories:
+
+### Built-in Type and Enum Components
+
+`pydase` automatically maps standard Python data types to their corresponding frontend components:
+
+- `str`: Translated into a `StringComponent` on the frontend.
+- `int` and `float`: Manifested as the `NumberComponent`.
+- `bool`: Rendered as a `ButtonComponent`.
+- `list`: Each item displayed individually, named after the list attribute and its index.
+- `enum.Enum`: Presented as an `EnumComponent`, facilitating dropdown selection.
+
+### Method Components
+
+Methods within the `DataService` class have frontend representations:
+
+- Regular Methods: These are rendered as a `MethodComponent` in the frontend, allowing users to execute the method via an "execute" button.
+- Asynchronous Methods: These are manifested as the `AsyncMethodComponent` with "start"/"stop" buttons to manage the execution of [tasks](#understanding-tasks-in-pydase).
+
+### DataService Instances (Nested Classes)
+
+Nested `DataService` instances offer an organized hierarchy for components, enabling richer applications. Each nested class might have its own attributes and methods, each mapped to a frontend component.
+
+Here is an example:
+
+```python
+from pydase import DataService, Server
+
+
+class Channel(DataService):
+    def __init__(self, channel_id: int) -> None:
+        self._channel_id = channel_id
+        self._current = 0.0
+        super().__init__()
+
+    @property
+    def current(self) -> float:
+        # run code to get current
+        result = self._current
+        return result
+
+    @current.setter
+    def current(self, value: float) -> None:
+        # run code to set current
+        self._current = value
+
+
+class Device(DataService):
+    def __init__(self) -> None:
+        self.channels = [Channel(i) for i in range(2)]
+
+        super().__init__()
+
+
+if __name__ == "__main__":
+    service = Device()
+    Server(service).run()
+```
+
+![Nested Classes App](docs/images/Nested_Class_App.png)
+
+**Note** that defining classes within `DataService` classes is not supported (see [this issue](https://github.com/tiqi-group/pydase/issues/16)).
+
+### Custom Components (`pydase.components`)
+
+The custom components in `pydase` have two main parts:
+
+- A **Python Component Class** in the backend, implementing the logic needed to set, update, and manage the component's state and data.
+- A **Frontend React Component** that renders and manages user interaction in the browser.
+
+Below are the components available in the `pydase.components` module, accompanied by their Python usage:
+
+#### `Image`
+
+This component provides a versatile interface for displaying images within the application. Users can update and manage images from various sources, including local paths, URLs, and even matplotlib figures.
+
+The component offers methods to load images seamlessly, ensuring that visual content is easily integrated and displayed within the data service.
+
+```python
+import matplotlib.pyplot as plt
+import numpy as np
+
+import pydase
+from pydase.components.image import Image
+
+
+class MyDataService(pydase.DataService):
+    my_image = Image()
+
+
+if __name__ == "__main__":
+    service = MyDataService()
+    # loading from local path
+    service.my_image.load_from_path("/your/image/path/")
+
+    # loading from a URL
+    service.my_image.load_from_url("https://cataas.com/cat")
+
+    # loading a matplotlib figure
+    fig = plt.figure()
+    x = np.linspace(0, 2 * np.pi)
+    plt.plot(x, np.sin(x))
+    plt.grid()
+    service.my_image.load_from_matplotlib_figure(fig)
+
+    pydase.Server(service).run()
+```
+
+![Image Component](docs/images/Image_component.png)
+
+#### `NumberSlider`
+
+This component provides an interactive slider interface for adjusting numerical values on the frontend. It supports both floats and integers. The values adjusted on the frontend are synchronized with the backend in real-time, ensuring consistent data representation.
+
+The slider can be customized with initial values, minimum and maximum limits, and step sizes to fit various use cases.
+
+```python
+import pydase
+from pydase.components import NumberSlider
+
+
+class MyService(pydase.DataService):
+    slider = NumberSlider(value=3.5, min=0, max=10, step_size=0.1, type="float")
+
+
+if __name__ == "__main__":
+    service = MyService()
+    pydase.Server(service).run()
+```
+
+![Slider Component](docs/images/Slider_component.png)
+
+#### `ColouredEnum`
+
+This component provides a way to visually represent different states or categories in a data service using colour-coded options. It behaves similarly to a standard `Enum`, but the values encode colours in a format understood by CSS. The colours can be defined using various methods like Hexadecimal, RGB, HSL, and more.
+
+If the property associated with the `ColouredEnum` has a setter function, the keys of the enum will be rendered as a dropdown menu, allowing users to interact and select different options. Without a setter function, the selected key will simply be displayed as a coloured box with text inside, serving as a visual indicator.
+
+```python
+import pydase
+import pydase.components as pyc
+
+
+class MyStatus(pyc.ColouredEnum):
+    PENDING = "#FFA500"  # Hexadecimal colour (Orange)
+    RUNNING = "#0000FF80"  # Hexadecimal colour with transparency (Blue)
+    PAUSED = "rgb(169, 169, 169)"  # RGB colour (Dark Gray)
+    RETRYING = "rgba(255, 255, 0, 0.3)"  # RGB colour with transparency (Yellow)
+    COMPLETED = "hsl(120, 100%, 50%)"  # HSL colour (Green)
+    FAILED = "hsla(0, 100%, 50%, 0.7)"  # HSL colour with transparency (Red)
+    CANCELLED = "SlateGray"  # Cross-browser colour name (Slate Gray)
+
+
+class StatusTest(pydase.DataService):
+    _status = MyStatus.RUNNING
+
+    @property
+    def status(self) -> MyStatus:
+        return self._status
+
+    @status.setter
+    def status(self, value: MyStatus) -> None:
+        # do something ...
+        self._status = value
+
+# Modifying or accessing the status value:
+my_service = StatusExample()
+my_service.status = MyStatus.FAILED
+```
+
+![ColouredEnum Component](docs/images/ColouredEnum_component.png)
+
+#### Extending with New Components
+
+Users can also extend the library by creating custom components. This involves defining the behavior on the Python backend and the visual representation on the frontend. For those looking to introduce new components, the [guide on adding components](https://pydase.readthedocs.io/en/latest/dev-guide/Adding_Components/) provides detailed steps on achieving this.
+
+<!-- Component User Guide End -->
+
+## Customizing Web Interface Style
+
+`pydase` allows you to enhance the user experience by customizing the web interface's appearance. You can apply your own styles globally across the web interface by passing a custom CSS file to the server during initialization.
+
+Here's how you can use this feature:
+
+1. Prepare your custom CSS file with the desired styles.
+
+2. When initializing your server, use the `css` parameter of the `Server` class to specify the path to your custom CSS file.
+
+```python
+from pydase import Server, DataService
+
+class Device(DataService):
+    # ... your service definition ...
+
+if __name__ == "__main__":
+    service = MyService()
+    server = Server(service, css="path/to/your/custom.css").run()
+```
+
+This will apply the styles defined in `custom.css` to the web interface, allowing you to maintain branding consistency or improve visual accessibility.
+
+Please ensure that the CSS file path is accessible from the server's running location. Relative or absolute paths can be used depending on your setup.
+
 ## Understanding Service Persistence
 
-`pydase` allows you to easily persist the state of your service by saving it to a file. This is especially useful when you want to maintain the service's state across different runs. 
+`pydase` allows you to easily persist the state of your service by saving it to a file. This is especially useful when you want to maintain the service's state across different runs.
 
-To save the state of your service, pass a `filename` keyword argument to the `__init__` method of the `DataService` base class. If the file specified by `filename` does not exist, the service will create this file and store its state in it when the service is shut down. If the file already exists, the service will load the state from this file, setting the values of its attributes to the values stored in the file. 
+To save the state of your service, pass a `filename` keyword argument to the constructor of the `pydase.Server` class. If the file specified by `filename` does not exist, the state manager will create this file and store its state in it when the service is shut down. If the file already exists, the state manager will load the state from this file, setting the values of its attributes to the values stored in the file.
 
 Here's an example:
 
@@ -156,23 +388,42 @@ Here's an example:
 from pydase import DataService, Server
 
 class Device(DataService):
-    def __init__(self, filename: str) -> None:
-        # ... your init code ...
-
-        # Pass the filename argument to the parent class
-        super().__init__(filename=filename)
-
     # ... defining the Device class ...
 
 
 if __name__ == "__main__":
-    service = Device("device_state.json")
-    Server(service).run()
+    service = Device()
+    Server(service, filename="device_state.json").run()
 ```
 
-In this example, the state of the `Device` service will be saved to `device_state.json` when the service is shut down. If `device_state.json` exists when the service is started, the service will restore its state from this file.
+In this example, the state of the `Device` service will be saved to `device_state.json` when the service is shut down. If `device_state.json` exists when the server is started, the state manager will restore the state of the service from this file.
 
-Note: If the service class structure has changed since the last time its state was saved, only the attributes that have remained the same will be restored from the settings file.
+### Controlling Property State Loading with `@load_state`
+
+By default, the state manager only restores values for public attributes of your service. If you have properties that you want to control the loading for, you can use the `@load_state` decorator on your property setters. This indicates to the state manager that the value of the property should be loaded from the state file.
+
+Here is how you can apply the `@load_state` decorator:
+
+```python
+from pydase import DataService
+from pydase.data_service.state_manager import load_state
+
+class Device(DataService):
+    _name = "Default Device Name"
+
+    @property
+    def name(self) -> str:
+        return self._name
+
+    @name.setter
+    @load_state
+    def name(self, value: str) -> None:
+        self._name = value
+```
+
+With the `@load_state` decorator applied to the `name` property setter, the state manager will load and apply the `name` property's value from the file storing the state upon server startup, assuming it exists.
+
+Note: If the service class structure has changed since the last time its state was saved, only the attributes and properties decorated with `@load_state` that have remained the same will be restored from the settings file.
 
 ## Understanding Tasks in pydase
 
@@ -279,14 +530,40 @@ if __name__ == "__main__":
 
 For more information about what you can do with the units, please consult the documentation of [`pint`](https://pint.readthedocs.io/en/stable/).
 
+## Changing the Log Level
+
+You can change the log level of the logger by either
+
+1. (RECOMMENDED) setting the `ENVIRONMENT` environment variable to "production" or "development"
+
+   ```bash
+   ENVIRONMENT="production" python -m <module_using_pydase>
+   ```
+
+   The production environment will only log messages above "INFO", the development environment (default) logs everything above "DEBUG".
+
+2. calling the `pydase.utils.logging.setup_logging` function with the desired log level
+
+   ```python
+   # <your_script.py>
+   import logging
+   from pydase.utils.logging import setup_logging
+
+   setup_logging("INFO")  # or setup_logging(logging.INFO)
+   logger = logging.getLogger()
+
+   # ... and your log
+   logger.info("My info message.")
+   ```
+
 ## Documentation
 
-The full documentation provides more detailed information about `pydase`, including advanced usage examples, API references, and tips for troubleshooting common issues. See the [full documentation](URL_TO_YOUR_DOCUMENTATION) for more information.
+The full documentation provides more detailed information about `pydase`, including advanced usage examples, API references, and tips for troubleshooting common issues. See the [full documentation](https://pydase.readthedocs.io/en/latest/) for more information.
 
 ## Contributing
 
-We welcome contributions! Please see [CONTRIBUTING.md](URL_TO_YOUR_CONTRIBUTING_GUIDELINES) for details on how to contribute.
+We welcome contributions! Please see [contributing.md](https://pydase.readthedocs.io/en/latest/about/contributing/) for details on how to contribute.
 
 ## License
 
-`pydase` is licensed under the [MIT License](./LICENSE).
+`pydase` is licensed under the [MIT License](https://github.com/tiqi-group/pydase/blob/main/LICENSE).

docs/about/license.md

@@ -0,0 +1,10 @@
+License
+=======
+`pydase` is released under the *MIT license*:
+
+```{.license}
+{%
+include "../../LICENSE"
+comments=false
+%}
+```

docs/css/extra.css

@@ -0,0 +1,3 @@
+.language-license{
+    background-color: #eeffcc !important;
+}

docs/dev-guide/Adding_Components.md

@@ -0,0 +1,307 @@
+# Adding Components to `pydase`
+
+This guide provides a step-by-step process for adding new components to the `pydase` package. Components in `pydase` consist of both backend (Python) and frontend (React) parts. They work together to create interactive and dynamic data services.
+
+## Overview
+
+A component in `pydase` is a unique combination of a backend class (e.g., `Image`) and its corresponding frontend React component. The backend class stores the attributes needed for the component, and possibly methods for setting those in the backend, while the frontend part is responsible for rendering and interacting with the component.
+
+## Adding a Backend Component to `pydase`
+
+Backend components belong in the `src/pydase/components` directory.
+
+### Step 1: Create a New Python File in the Components Directory
+
+Navigate to the `src/pydase/components` directory and create a new Python file for your component. The name of the file should be descriptive of the component's functionality.
+
+For example, for a `Image` component, create a file named `image.py`.
+
+### Step 2: Define the Backend Class
+
+Within the newly created file, define a Python class representing the component. This class should inherit from `DataService` and contains the attributes that the frontend needs to render the component. Every public attribute defined in this class will synchronise across the clients. It can also contain methods which can be used to interact with the component from the backend.
+
+For the `Image` component, the class may look like this:
+
+```python
+# file: pydase/components/image.py
+
+from pydase.data_service.data_service import DataService
+
+
+class Image(DataService):
+    def __init__(
+        self,
+        image_representation: bytes = b"",
+    ) -> None:
+        self.image_representation = image_representation
+        super().__init__()
+
+    # need to decode the bytes
+    def __setattr__(self, __name: str, __value: Any) -> None:
+        if __name == "value":
+            if isinstance(__value, bytes):
+                __value = __value.decode()
+        return super().__setattr__(__name, __value)
+
+```
+
+So, changing the `image_representation` will push the updated value to the browsers connected to the service.
+
+### Step 3: Register the Backend Class
+
+The component should be added to the `__init__.py` file to ensure `pydase` handles them properly:
+
+```python
+# file: pydase/components/__init__.py
+
+from pydase.components.image import Image
+from pydase.components.number_slider import NumberSlider
+
+__all__ = [
+    "NumberSlider",
+    "Image",  # add the new components here
+]
+
+```
+
+### Step 4: Implement Necessary Methods (Optional)
+
+If your component requires specific logic or methods, implement them within the class. Document any public methods or attributes to ensure that other developers understand their purpose and usage.
+
+### Step 5: Write Tests for the Component (Recommended)
+
+Consider writing unit tests for the component to verify its behavior. Place the tests in the appropriate directory within the `tests` folder.
+
+For example, a test for the `Image` component could look like this:
+
+```python
+from pytest import CaptureFixture
+
+from pydase.components.image import Image
+from pydase.data_service.data_service import DataService
+
+
+def test_Image(capsys: CaptureFixture) -> None:
+    class ServiceClass(DataService):
+        image = Image()
+
+    service = ServiceClass()
+    # ...
+```
+
+
+## Adding a Frontend Component to `pydase`
+
+Frontend components in `pydase` live in the `frontend/src/components/` directory. Follow these steps to create and add a new frontend component:
+
+### Step 1: Create a New React Component File in the Components Directory
+
+Navigate to the `frontend/src/components/` directory and create a new React component file for your component. The name of the file should be descriptive of the component's functionality and reflect the naming conventions used in your project.
+
+For example, for an `Image` component, create a file named `ImageComponent.tsx`.
+
+### Step 2: Write the React Component Code
+
+Write the React component code, following the structure and patterns used in existing components. Make sure to import necessary libraries and dependencies.
+
+For example, for the `Image` component, a template could look like this:
+
+```tsx
+import { setAttribute, runMethod } from '../socket';  // use this when your component should sets values of attributes
+                                                      // or runs a method, respectively
+import { DocStringComponent } from './DocStringComponent';
+import React, { useEffect, useRef, useState } from 'react';
+import { Card, Collapse, Image } from 'react-bootstrap';
+import { DocStringComponent } from './DocStringComponent';
+import { ChevronDown, ChevronRight } from 'react-bootstrap-icons';
+import { getIdFromFullAccessPath } from '../utils/stringUtils';
+
+interface ImageComponentProps {
+  name: string;
+  parentPath: string;
+  readOnly: boolean;
+  docString: string;
+  addNotification: (message: string) => void;
+  // Define your component specific props here
+  value: string;
+  format: string;
+}
+
+export const ImageComponent = React.memo((props: ImageComponentProps) => {
+  const { name, parentPath, value, docString, format, addNotification } = props;
+
+  const renderCount = useRef(0);
+  const [open, setOpen] = useState(true);  // add this if you want to expand/collapse your component
+  const fullAccessPath = parentPath.concat('.' + name);
+  const id = getIdFromFullAccessPath(fullAccessPath);
+
+  useEffect(() => {
+    renderCount.current++;
+  });
+
+  // This will trigger a notification if notifications are enabled.
+  useEffect(() => {
+    addNotification(`${parentPath}.${name} changed to ${value}.`);
+  }, [props.value]);
+
+  // Your component logic here
+
+  return (
+    <div className={'imageComponent'} id={id}>
+      {/* Add the Card and Collapse components here if you want to be able to expand and
+       collapse your component.  */}
+      <Card>
+        <Card.Header
+          onClick={() => setOpen(!open)}
+          style={{ cursor: 'pointer' }} // Change cursor style on hover
+        >
+          {name} {open ? <ChevronDown /> : <ChevronRight />}
+        </Card.Header>
+        <Collapse in={open}>
+          <Card.Body>
+            {process.env.NODE_ENV === 'development' && (
+              <p>Render count: {renderCount.current}</p>
+            )}
+            <DocStringComponent docString={docString} />
+            {/* Your component TSX here */}
+          </Card.Body>
+        </Collapse>
+      </Card>
+    </div>
+  );
+});
+```
+
+### Step 3: Emitting Updates to the Backend
+
+React components in the frontend often need to send updates to the backend, particularly when user interactions modify the component's state or data. In `pydase`, we use `socketio` for smooth communication of these changes. To handle updates, we primarily use two events: `setAttribute` for updating attributes, and `runMethod` for executing backend methods. Below is a detailed guide on how to emit these events from your frontend component:
+
+1. **Setup for emitting events**:
+    First, ensure you've imported the necessary functions from the `socket` module for both updating attributes and executing methods:
+
+    ```tsx
+    import { setAttribute, runMethod } from '../socket';
+    ```
+
+2. **Event Parameters**:
+
+    - When using **`setAttribute`**, we send three main pieces of data:
+        - `name`: The name of the attribute within the `DataService` instance to update.
+        - `parentPath`: The access path for the parent object of the attribute to be updated.
+        - `value`: The new value for the attribute, which must match the backend attribute type.
+    - For **`runMethod`**, the parameters are slightly different:
+        - `name`: The name of the method to be executed in the backend.
+        - `parentPath`: Similar to `setAttribute`, it's the access path to the object containing the method.
+        - `kwargs`: A dictionary of keyword arguments that the method requires.
+
+3. **Implementation**:
+
+    For illustation, take the `ButtonComponent`. When the button state changes, we want to send this update to the backend:
+
+    ```tsx
+    import { setAttribute } from '../socket';
+    // ... (other imports)
+    
+    export const ButtonComponent = React.memo((props: ButtonComponentProps) => {
+      // ... 
+      const { name, parentPath, value } = props;
+
+      const setChecked = (checked: boolean) => {
+        setAttribute(name, parentPath, checked);
+      };
+
+      return (
+        <ToggleButton
+          checked={value}
+          value={parentPath}
+          // ... other props
+          onChange={(e) => setChecked(e.currentTarget.checked)}>
+          <p>{name}</p>
+        </ToggleButton>
+      );
+    });
+    ```
+
+    In this example, whenever the button's checked state changes (`onChange` event), we invoke the `setChecked` method, which in turn emits the new state to the backend using `setAttribute`.
+
+
+### Step 4: Add the New Component to the GenericComponent
+
+The `GenericComponent` is responsible for rendering different types of components based on the attribute type. You can add the new `ImageComponent` to the `GenericComponent` by following these sub-steps:
+
+#### 1. Import the New Component
+
+At the beginning of the `GenericComponent` file, import the newly created `ImageComponent`:
+
+```tsx
+// file: frontend/src/components/GenericComponent.tsx
+
+import { ImageComponent } from './ImageComponent';
+```
+
+#### 2. Update the AttributeType
+
+Update the `AttributeType` type definition to include the new type for the `ImageComponent`. 
+
+For example, if the new attribute type is `'Image'` (which should correspond to the name of the backend component class), you can add it to the union:
+
+```tsx
+type AttributeType =
+  | 'str'
+  | 'bool'
+  | 'float'
+  | 'int'
+  | 'Quantity'
+  | 'list'
+  | 'method'
+  | 'DataService'
+  | 'Enum'
+  | 'NumberSlider'
+  | 'Image'; // Add the name of the backend component class here
+```
+
+#### 3. Add a Conditional Branch for the New Component
+
+Inside the `GenericComponent` function, add a new conditional branch to render the `ImageComponent` when the attribute type is `'Image'`:
+
+```tsx
+} else if (attribute.type === 'Image') {
+  return (
+    <ImageComponent
+      name={name}
+      parentPath={parentPath}
+      readOnly={attribute.readonly}
+      docString={attribute.doc}
+      addNotification={addNotification}
+      // Add any other specific props for the ImageComponent here
+      value={attribute.value['value']['value'] as string}
+      format={attribute.value['format']['value'] as string}
+    />
+  );
+} else {
+  // other code
+```
+
+Make sure to update the props passed to the `ImageComponent` based on its specific requirements.
+
+### Step 5: Adding Custom Notification Message (Optional)
+
+In some cases, you may want to provide a custom notification message to the user when an attribute of a specific type is updated. This can be useful for enhancing user experience and providing contextual information about the changes.
+
+For example, updating an `Image` component corresponds to setting a very long string. We don't want to display the whole string in the notification but just notify the user that the image was updated (and maybe also the format).
+
+To create a custom notification message, you can update the message passed to the `addNotification` method in the `useEffect` hook in the component file file. For the `ImageComponent`, this could look like this:
+
+```tsx
+useEffect(() => {
+  addNotification(`${parentPath}.${name} changed.`);
+}, [props.value]);
+```
+
+However, you might want to use the `addNotification` at different places. For an example, see the [MethodComponent](../../frontend/src/components/MethodComponent.tsx).
+
+### Step 6: Write Tests for the Component (TODO)
+
+Test the frontend component to ensure that it renders correctly and interacts seamlessly
+with the backend. Consider writing unit tests using a testing library like Jest or React
+Testing Library, and manually test the component in the browser.

docs/dev-guide/README.md

@@ -0,0 +1,8 @@
+# Developer Guide
+
+Extending `pydase`.
+
+---
+
+- [API Reference](api.md)
+- [Adding Components](Adding_Components.md)

docs/getting-started.md

@@ -0,0 +1,14 @@
+# Getting Started
+## Installation
+{%
+   include-markdown "../README.md"
+   start="<!--installation-start-->"
+   end="<!--installation-end-->"
+%}
+
+## Usage
+{%
+   include-markdown "../README.md"
+   start="<!--usage-start-->"
+   end="<!--usage-end-->"
+%}

docs/index.md

@@ -0,0 +1 @@
+{% include-markdown "../README.md" %}

docs/requirements.txt

@@ -0,0 +1,20 @@
+click==8.1.7 ; python_version >= "3.10" and python_version < "4.0"
+colorama==0.4.6 ; python_version >= "3.10" and python_version < "4.0" and platform_system == "Windows"
+ghp-import==2.1.0 ; python_version >= "3.10" and python_version < "4.0"
+jinja2==3.1.2 ; python_version >= "3.10" and python_version < "4.0"
+markdown==3.4.4 ; python_version >= "3.10" and python_version < "4.0"
+markupsafe==2.1.3 ; python_version >= "3.10" and python_version < "4.0"
+mergedeep==1.3.4 ; python_version >= "3.10" and python_version < "4.0"
+mkdocs-autorefs==0.5.0 ; python_version >= "3.10" and python_version < "4.0"
+mkdocs-include-markdown-plugin==3.9.1 ; python_version >= "3.10" and python_version < "4.0"
+mkdocs==1.5.3 ; python_version >= "3.10" and python_version < "4.0"
+mkdocstrings==0.22.0 ; python_version >= "3.10" and python_version < "4.0"
+packaging==23.1 ; python_version >= "3.10" and python_version < "4.0"
+pathspec==0.11.2 ; python_version >= "3.10" and python_version < "4.0"
+platformdirs==3.10.0 ; python_version >= "3.10" and python_version < "4.0"
+pymdown-extensions==10.3 ; python_version >= "3.10" and python_version < "4.0"
+python-dateutil==2.8.2 ; python_version >= "3.10" and python_version < "4.0"
+pyyaml-env-tag==0.1 ; python_version >= "3.10" and python_version < "4.0"
+pyyaml==6.0.1 ; python_version >= "3.10" and python_version < "4.0"
+six==1.16.0 ; python_version >= "3.10" and python_version < "4.0"
+watchdog==3.0.0 ; python_version >= "3.10" and python_version < "4.0"

docs/user-guide/Components.md

@@ -0,0 +1,6 @@
+# Components Guide
+{%
+   include-markdown "../../README.md"
+   start="<!-- Component User Guide Start -->"
+   end="<!-- Component User Guide End -->"
+%}

frontend/.eslintrc

@@ -7,12 +7,10 @@
     ],
     "extends": [
         "eslint:recommended",
-        "plugin:@typescript-eslint/eslint-recommended",
         "plugin:@typescript-eslint/recommended",
         "prettier"
     ],
     "rules": {
-        "no-console": 1, // Means warning
-        "prettier/prettier": 2 // Means error  }
+        "prettier/prettier": "error"
     }
-}
+}

frontend/package.json

@@ -46,9 +46,12 @@
     "@types/node": "^20.0.0",
     "@types/react": "^18.0.0",
     "@types/react-dom": "^18.0.0",
-    "eslint-config-prettier": "^8.8.0",
-    "eslint-plugin-prettier": "^5.0.0",
-    "prettier": "^3.0.0",
-    "@babel/plugin-proposal-private-property-in-object": "7.21.11"
+    "@typescript-eslint/eslint-plugin": "^6.9.0",
+    "@typescript-eslint/parser": "^6.9.0",
+    "eslint": "^8.52.0",
+    "eslint-config-prettier": "^9.0.0",
+    "eslint-plugin-prettier": "^5.0.1",
+    "prettier": "^3.0.3",
+    "typescript": "^4.9.0"
   }
 }

frontend/src/App.tsx

@@ -7,6 +7,7 @@ import {
 } from './components/DataServiceComponent';
 import './App.css';
 import { Notifications } from './components/NotificationsComponent';
+import { ConnectionToast } from './components/ConnectionToast';
 
 type ValueType = boolean | string | number | object;
 
@@ -34,12 +35,6 @@ type ExceptionMessage = {
  *
  * If the property to be updated is an object or an array, it is updated
  * recursively.
- *
- * @param {Array<string>} path - An array where each element is a key in the object,
- * forming a path to the property to be updated.
- * @param {object} obj - The object to be updated.
- * @param {object} value - The new value for the property specified by the path.
- * @return {object} - A new object with the specified property updated.
  */
 function updateNestedObject(path: Array<string>, obj: object, value: ValueType) {
   // Base case: If the path is empty, return the new value.
@@ -108,15 +103,15 @@ const reducer = (state: State, action: Action): State => {
       throw new Error();
   }
 };
-
 const App = () => {
   const [state, dispatch] = useReducer(reducer, null);
   const stateRef = useRef(state); // Declare a reference to hold the current state
   const [isInstantUpdate, setIsInstantUpdate] = useState(false);
   const [showSettings, setShowSettings] = useState(false);
-  const [showNotification, setShowNotification] = useState(true);
+  const [showNotification, setShowNotification] = useState(false);
   const [notifications, setNotifications] = useState([]);
   const [exceptions, setExceptions] = useState([]);
+  const [connectionStatus, setConnectionStatus] = useState('connecting');
 
   // Keep the state reference up to date
   useEffect(() => {
@@ -124,10 +119,37 @@ const App = () => {
   }, [state]);
 
   useEffect(() => {
-    // Fetch data from the API when the component mounts
-    fetch(`http://${hostname}:${port}/service-properties`)
-      .then((response) => response.json())
-      .then((data: DataServiceJSON) => dispatch({ type: 'SET_DATA', data }));
+    // Allow the user to add a custom css file
+    fetch(`http://${hostname}:${port}/custom.css`)
+      .then((response) => {
+        if (response.ok) {
+          // If the file exists, create a link element for the custom CSS
+          const link = document.createElement('link');
+          link.href = `http://${hostname}:${port}/custom.css`;
+          link.type = 'text/css';
+          link.rel = 'stylesheet';
+          document.head.appendChild(link);
+        }
+      })
+      .catch(console.error); // Handle the error appropriately
+
+    socket.on('connect', () => {
+      // Fetch data from the API when the client connects
+      fetch(`http://${hostname}:${port}/service-properties`)
+        .then((response) => response.json())
+        .then((data: DataServiceJSON) => dispatch({ type: 'SET_DATA', data }));
+      setConnectionStatus('connected');
+    });
+    socket.on('disconnect', () => {
+      setConnectionStatus('disconnected');
+      setTimeout(() => {
+        // Only set "reconnecting" is the state is still "disconnected"
+        // E.g. when the client has already reconnected
+        setConnectionStatus((currentState) =>
+          currentState === 'disconnected' ? 'reconnecting' : currentState
+        );
+      }, 2000);
+    });
 
     socket.on('notify', onNotify);
     socket.on('exception', onException);
@@ -198,7 +220,7 @@ const App = () => {
 
   // While the data is loading
   if (!state) {
-    return <p>Loading...</p>;
+    return <ConnectionToast connectionStatus={connectionStatus} />;
   }
   return (
     <>
@@ -244,11 +266,13 @@ const App = () => {
 
       <div className="App navbarOffset">
         <DataServiceComponent
+          name={''}
           props={state as DataServiceJSON}
           isInstantUpdate={isInstantUpdate}
           addNotification={addNotification}
         />
       </div>
+      <ConnectionToast connectionStatus={connectionStatus} />
     </>
   );
 };

frontend/src/components/AsyncMethodComponent.tsx

@@ -1,7 +1,8 @@
 import React, { useEffect, useRef } from 'react';
-import { emit_update } from '../socket';
+import { runMethod } from '../socket';
 import { InputGroup, Form, Button } from 'react-bootstrap';
 import { DocStringComponent } from './DocStringComponent';
+import { getIdFromFullAccessPath } from '../utils/stringUtils';
 
 interface AsyncMethodProps {
   name: string;
@@ -10,13 +11,14 @@ interface AsyncMethodProps {
   value: Record<string, string>;
   docString?: string;
   hideOutput?: boolean;
-  addNotification: (string) => void;
+  addNotification: (message: string) => void;
 }
 
 export const AsyncMethodComponent = React.memo((props: AsyncMethodProps) => {
   const { name, parentPath, docString, value: runningTask, addNotification } = props;
   const renderCount = useRef(0);
   const formRef = useRef(null);
+  const id = getIdFromFullAccessPath(parentPath.concat('.' + name));
 
   useEffect(() => {
     renderCount.current++;
@@ -54,18 +56,18 @@ export const AsyncMethodComponent = React.memo((props: AsyncMethodProps) => {
   const execute = async (event: React.FormEvent) => {
     event.preventDefault();
     let method_name: string;
-    const args = {};
+    const kwargs: Record<string, unknown> = {};
 
     if (runningTask !== undefined && runningTask !== null) {
       method_name = `stop_${name}`;
     } else {
       Object.keys(props.parameters).forEach(
-        (name) => (args[name] = event.target[name].value)
+        (name) => (kwargs[name] = event.target[name].value)
       );
       method_name = `start_${name}`;
     }
 
-    emit_update(method_name, parentPath, { args: args });
+    runMethod(method_name, parentPath, kwargs);
   };
 
   const args = Object.entries(props.parameters).map(([name, type], index) => {
@@ -87,9 +89,7 @@ export const AsyncMethodComponent = React.memo((props: AsyncMethodProps) => {
   });
 
   return (
-    <div
-      className="align-items-center asyncMethodComponent"
-      id={parentPath.concat('.' + name)}>
+    <div className="align-items-center asyncMethodComponent" id={id}>
       {process.env.NODE_ENV === 'development' && (
         <p>Render count: {renderCount.current}</p>
       )}
@@ -99,11 +99,7 @@ export const AsyncMethodComponent = React.memo((props: AsyncMethodProps) => {
       </h5>
       <Form onSubmit={execute} ref={formRef}>
         {args}
-        <Button
-          id={`button-${parentPath}.${name}`}
-          name={name}
-          value={parentPath}
-          type="submit">
+        <Button id={`button-${id}`} name={name} value={parentPath} type="submit">
           {runningTask ? 'Stop' : 'Start'}
         </Button>
       </Form>

frontend/src/components/ButtonComponent.tsx

@@ -1,7 +1,8 @@
 import React, { useEffect, useRef } from 'react';
 import { ToggleButton } from 'react-bootstrap';
-import { emit_update } from '../socket';
+import { setAttribute } from '../socket';
 import { DocStringComponent } from './DocStringComponent';
+import { getIdFromFullAccessPath } from '../utils/stringUtils';
 
 interface ButtonComponentProps {
   name: string;
@@ -10,13 +11,14 @@ interface ButtonComponentProps {
   readOnly: boolean;
   docString: string;
   mapping?: [string, string]; // Enforce a tuple of two strings
-  addNotification: (string) => void;
+  addNotification: (message: string) => void;
 }
 
 export const ButtonComponent = React.memo((props: ButtonComponentProps) => {
   const { name, parentPath, value, readOnly, docString, mapping, addNotification } =
     props;
   const buttonName = mapping ? (value ? mapping[0] : mapping[1]) : name;
+  const id = getIdFromFullAccessPath(parentPath.concat('.' + name));
 
   const renderCount = useRef(0);
 
@@ -29,18 +31,18 @@ export const ButtonComponent = React.memo((props: ButtonComponentProps) => {
   }, [props.value]);
 
   const setChecked = (checked: boolean) => {
-    emit_update(name, parentPath, checked);
+    setAttribute(name, parentPath, checked);
   };
 
   return (
-    <div className={'buttonComponent'} id={parentPath.concat('.' + name)}>
+    <div className={'buttonComponent'} id={id}>
       {process.env.NODE_ENV === 'development' && (
         <p>Render count: {renderCount.current}</p>
       )}
 
       <DocStringComponent docString={docString} />
       <ToggleButton
-        id={`toggle-check-${parentPath}.${name}`}
+        id={`toggle-check-${id}`}
         type="checkbox"
         variant={value ? 'success' : 'secondary'}
         checked={value}

frontend/src/components/ColouredEnumComponent.tsx

@@ -0,0 +1,76 @@
+import React, { useEffect, useRef } from 'react';
+import { InputGroup, Form, Row, Col } from 'react-bootstrap';
+import { setAttribute } from '../socket';
+import { DocStringComponent } from './DocStringComponent';
+import { getIdFromFullAccessPath } from '../utils/stringUtils';
+
+interface ColouredEnumComponentProps {
+  name: string;
+  parentPath: string;
+  value: string;
+  docString?: string;
+  readOnly: boolean;
+  enumDict: Record<string, string>;
+  addNotification: (message: string) => void;
+}
+
+export const ColouredEnumComponent = React.memo((props: ColouredEnumComponentProps) => {
+  const {
+    name,
+    parentPath: parentPath,
+    value,
+    docString,
+    enumDict,
+    readOnly,
+    addNotification
+  } = props;
+  const renderCount = useRef(0);
+  const id = getIdFromFullAccessPath(parentPath.concat('.' + name));
+
+  useEffect(() => {
+    renderCount.current++;
+  });
+
+  useEffect(() => {
+    addNotification(`${parentPath}.${name} changed to ${value}.`);
+  }, [props.value]);
+
+  const handleValueChange = (newValue: string) => {
+    setAttribute(name, parentPath, newValue);
+  };
+
+  return (
+    <div className={'enumComponent'} id={id}>
+      {process.env.NODE_ENV === 'development' && (
+        <p>Render count: {renderCount.current}</p>
+      )}
+      <DocStringComponent docString={docString} />
+      <Row>
+        <Col className="d-flex align-items-center">
+          <InputGroup.Text>{name}</InputGroup.Text>
+          {readOnly ? (
+            // Display the Form.Control when readOnly is true
+            <Form.Control
+              value={value}
+              disabled={true}
+              style={{ backgroundColor: enumDict[value] }}
+            />
+          ) : (
+            // Display the Form.Select when readOnly is false
+            <Form.Select
+              aria-label="coloured-enum-select"
+              value={value}
+              style={{ backgroundColor: enumDict[value] }}
+              onChange={(event) => handleValueChange(event.target.value)}>
+              {Object.entries(enumDict).map(([key]) => (
+                <option key={key} value={key}>
+                  {key}
+                </option>
+              ))}
+            </Form.Select>
+          )}
+        </Col>
+      </Row>
+    </div>
+  );
+});

frontend/src/components/ConnectionToast.tsx

@@ -0,0 +1,86 @@
+import React, { useEffect, useState } from 'react';
+import { Toast, Button, ToastContainer } from 'react-bootstrap';
+
+type ConnectionToastProps = {
+  connectionStatus: string;
+};
+
+/**
+ * ConnectionToast Component
+ *
+ * Displays a toast notification that reflects the current connection status.
+ *
+ * Props:
+ * - connectionStatus (string): The current status of the connection which can be
+ *   'connecting', 'connected', 'disconnected', or 'reconnecting'. The component uses this
+ *   status to determine the message, background color (`bg`), and auto-hide delay of the toast.
+ *
+ * The toast is designed to automatically appear based on changes to the `connectionStatus` prop
+ * and provides a close button to manually dismiss the toast. It uses `react-bootstrap`'s Toast
+ * component to show the connection status in a stylized format, and Bootstrap's utility classes
+ * for alignment and spacing.
+ */
+export const ConnectionToast = React.memo(
+  ({ connectionStatus }: ConnectionToastProps) => {
+    const [show, setShow] = useState(true);
+
+    useEffect(() => {
+      setShow(true);
+    }, [connectionStatus]);
+
+    const handleClose = () => setShow(false);
+
+    const getToastContent = (): {
+      message: string;
+      bg: string; // bootstrap uses `bg` prop for background color
+      delay: number | undefined;
+    } => {
+      switch (connectionStatus) {
+        case 'connecting':
+          return {
+            message: 'Connecting...',
+            bg: 'info',
+            delay: undefined
+          };
+        case 'connected':
+          return { message: 'Connected', bg: 'success', delay: 1000 };
+        case 'disconnected':
+          return {
+            message: 'Disconnected',
+            bg: 'danger',
+            delay: undefined
+          };
+        case 'reconnecting':
+          return {
+            message: 'Reconnecting...',
+            bg: 'info',
+            delay: undefined
+          };
+        default:
+          return {
+            message: '',
+            bg: 'info',
+            delay: undefined
+          };
+      }
+    };
+
+    const { message, bg, delay } = getToastContent();
+
+    return (
+      <ToastContainer position="bottom-center">
+        <Toast
+          show={show}
+          onClose={handleClose}
+          delay={delay}
+          autohide={delay !== undefined}
+          bg={bg}>
+          <Toast.Body className="d-flex justify-content-between">
+            {message}
+            <Button variant="close" size="sm" onClick={handleClose} />
+          </Toast.Body>
+        </Toast>
+      </ToastContainer>
+    );
+  }
+);

frontend/src/components/DataServiceComponent.tsx

@@ -3,33 +3,41 @@ import React from 'react';
 import { Card, Collapse } from 'react-bootstrap';
 import { ChevronDown, ChevronRight } from 'react-bootstrap-icons';
 import { Attribute, GenericComponent } from './GenericComponent';
+import { getIdFromFullAccessPath } from '../utils/stringUtils';
 
 type DataServiceProps = {
+  name: string;
   props: DataServiceJSON;
   parentPath?: string;
   isInstantUpdate: boolean;
-  addNotification: (string) => void;
+  addNotification: (message: string) => void;
 };
 
 export type DataServiceJSON = Record<string, Attribute>;
 
 export const DataServiceComponent = React.memo(
   ({
+    name,
     props,
     parentPath = 'DataService',
     isInstantUpdate,
     addNotification
   }: DataServiceProps) => {
     const [open, setOpen] = useState(true);
+    let fullAccessPath = parentPath;
+    if (name) {
+      fullAccessPath = parentPath.concat('.' + name);
+    }
+    const id = getIdFromFullAccessPath(fullAccessPath);
 
     return (
-      <div className="dataServiceComponent">
+      <div className="dataServiceComponent" id={id}>
         <Card className="mb-3">
           <Card.Header
             onClick={() => setOpen(!open)}
             style={{ cursor: 'pointer' }} // Change cursor style on hover
           >
-            {parentPath} {open ? <ChevronDown /> : <ChevronRight />}
+            {fullAccessPath} {open ? <ChevronDown /> : <ChevronRight />}
           </Card.Header>
           <Collapse in={open}>
             <Card.Body>
@@ -39,7 +47,7 @@ export const DataServiceComponent = React.memo(
                     key={key}
                     attribute={value}
                     name={key}
-                    parentPath={parentPath}
+                    parentPath={fullAccessPath}
                     isInstantUpdate={isInstantUpdate}
                     addNotification={addNotification}
                   />

frontend/src/components/EnumComponent.tsx

@@ -1,6 +1,6 @@
 import React, { useEffect, useRef } from 'react';
 import { InputGroup, Form, Row, Col } from 'react-bootstrap';
-import { emit_update } from '../socket';
+import { setAttribute } from '../socket';
 import { DocStringComponent } from './DocStringComponent';
 
 interface EnumComponentProps {
@@ -9,7 +9,7 @@ interface EnumComponentProps {
   value: string;
   docString?: string;
   enumDict: Record<string, string>;
-  addNotification: (string) => void;
+  addNotification: (message: string) => void;
 }
 
 export const EnumComponent = React.memo((props: EnumComponentProps) => {
@@ -33,7 +33,7 @@ export const EnumComponent = React.memo((props: EnumComponentProps) => {
   }, [props.value]);
 
   const handleValueChange = (newValue: string) => {
-    emit_update(name, parentPath, newValue);
+    setAttribute(name, parentPath, newValue);
   };
 
   return (

frontend/src/components/GenericComponent.tsx

@@ -9,6 +9,7 @@ import { StringComponent } from './StringComponent';
 import { ListComponent } from './ListComponent';
 import { DataServiceComponent, DataServiceJSON } from './DataServiceComponent';
 import { ImageComponent } from './ImageComponent';
+import { ColouredEnumComponent } from './ColouredEnumComponent';
 
 type AttributeType =
   | 'str'
@@ -21,7 +22,8 @@ type AttributeType =
   | 'DataService'
   | 'Enum'
   | 'NumberSlider'
-  | 'Image';
+  | 'Image'
+  | 'ColouredEnum';
 
 type ValueType = boolean | string | number | object;
 export interface Attribute {
@@ -38,7 +40,7 @@ type GenericComponentProps = {
   name: string;
   parentPath: string;
   isInstantUpdate: boolean;
-  addNotification: (string) => void;
+  addNotification: (message: string) => void;
 };
 
 export const GenericComponent = React.memo(
@@ -151,8 +153,9 @@ export const GenericComponent = React.memo(
     } else if (attribute.type === 'DataService') {
       return (
         <DataServiceComponent
+          name={name}
           props={attribute.value as DataServiceJSON}
-          parentPath={parentPath.concat('.', name)}
+          parentPath={parentPath}
           isInstantUpdate={isInstantUpdate}
           addNotification={addNotification}
         />
@@ -181,6 +184,19 @@ export const GenericComponent = React.memo(
           addNotification={addNotification}
         />
       );
+    } else if (attribute.type === 'ColouredEnum') {
+      console.log(attribute);
+      return (
+        <ColouredEnumComponent
+          name={name}
+          parentPath={parentPath}
+          docString={attribute.doc}
+          value={String(attribute.value)}
+          readOnly={attribute.readonly}
+          enumDict={attribute.enum}
+          addNotification={addNotification}
+        />
+      );
     } else {
       return <div key={name}>{name}</div>;
     }

frontend/src/components/ImageComponent.tsx

@@ -2,6 +2,7 @@ import React, { useEffect, useRef, useState } from 'react';
 import { Card, Collapse, Image } from 'react-bootstrap';
 import { DocStringComponent } from './DocStringComponent';
 import { ChevronDown, ChevronRight } from 'react-bootstrap-icons';
+import { getIdFromFullAccessPath } from '../utils/stringUtils';
 
 interface ImageComponentProps {
   name: string;
@@ -10,7 +11,7 @@ interface ImageComponentProps {
   readOnly: boolean;
   docString: string;
   format: string;
-  addNotification: (string) => void;
+  addNotification: (message: string) => void;
 }
 
 export const ImageComponent = React.memo((props: ImageComponentProps) => {
@@ -18,6 +19,7 @@ export const ImageComponent = React.memo((props: ImageComponentProps) => {
 
   const renderCount = useRef(0);
   const [open, setOpen] = useState(true);
+  const id = getIdFromFullAccessPath(parentPath.concat('.' + name));
 
   useEffect(() => {
     renderCount.current++;
@@ -28,7 +30,7 @@ export const ImageComponent = React.memo((props: ImageComponentProps) => {
   }, [props.value]);
 
   return (
-    <div className={'imageComponent'} id={parentPath.concat('.' + name)}>
+    <div className={'imageComponent'} id={id}>
       <Card>
         <Card.Header
           onClick={() => setOpen(!open)}

frontend/src/components/ListComponent.tsx

@@ -1,6 +1,7 @@
 import React, { useEffect, useRef } from 'react';
 import { DocStringComponent } from './DocStringComponent';
 import { Attribute, GenericComponent } from './GenericComponent';
+import { getIdFromFullAccessPath } from '../utils/stringUtils';
 
 interface ListComponentProps {
   name: string;
@@ -8,7 +9,7 @@ interface ListComponentProps {
   value: Attribute[];
   docString: string;
   isInstantUpdate: boolean;
-  addNotification: (string) => void;
+  addNotification: (message: string) => void;
 }
 
 export const ListComponent = React.memo((props: ListComponentProps) => {
@@ -16,13 +17,14 @@ export const ListComponent = React.memo((props: ListComponentProps) => {
     props;
 
   const renderCount = useRef(0);
+  const id = getIdFromFullAccessPath(parentPath.concat('.' + name));
 
   useEffect(() => {
     renderCount.current++;
   }, [props]);
 
   return (
-    <div className={'listComponent'} id={parentPath.concat(name)}>
+    <div className={'listComponent'} id={id}>
       {process.env.NODE_ENV === 'development' && (
         <p>Render count: {renderCount.current}</p>
       )}

frontend/src/components/MethodComponent.tsx

@@ -1,7 +1,8 @@
 import React, { useState, useEffect, useRef } from 'react';
-import { emit_update } from '../socket';
+import { runMethod } from '../socket';
 import { Button, InputGroup, Form, Collapse } from 'react-bootstrap';
 import { DocStringComponent } from './DocStringComponent';
+import { getIdFromFullAccessPath } from '../utils/stringUtils';
 
 interface MethodProps {
   name: string;
@@ -9,7 +10,7 @@ interface MethodProps {
   parameters: Record<string, string>;
   docString?: string;
   hideOutput?: boolean;
-  addNotification: (string) => void;
+  addNotification: (message: string) => void;
 }
 
 export const MethodComponent = React.memo((props: MethodProps) => {
@@ -19,6 +20,7 @@ export const MethodComponent = React.memo((props: MethodProps) => {
   const [hideOutput, setHideOutput] = useState(false);
   // Add a new state variable to hold the list of function calls
   const [functionCalls, setFunctionCalls] = useState([]);
+  const id = getIdFromFullAccessPath(parentPath.concat('.' + name));
 
   useEffect(() => {
     renderCount.current++;
@@ -44,18 +46,21 @@ export const MethodComponent = React.memo((props: MethodProps) => {
   const execute = async (event: React.FormEvent) => {
     event.preventDefault();
 
-    const args = {};
+    const kwargs = {};
     Object.keys(props.parameters).forEach(
-      (name) => (args[name] = event.target[name].value)
+      (name) => (kwargs[name] = event.target[name].value)
     );
-    emit_update(name, parentPath, { args: args }, (ack) => {
+    runMethod(name, parentPath, kwargs, (ack) => {
       // Update the functionCalls state with the new call if we get an acknowledge msg
       if (ack !== undefined) {
-        setFunctionCalls((prevCalls) => [...prevCalls, { name, args, result: ack }]);
+        setFunctionCalls((prevCalls) => [
+          ...prevCalls,
+          { name, args: kwargs, result: ack }
+        ]);
       }
     });
 
-    triggerNotification(args);
+    triggerNotification(kwargs);
   };
 
   const args = Object.entries(props.parameters).map(([name, type], index) => {
@@ -69,9 +74,7 @@ export const MethodComponent = React.memo((props: MethodProps) => {
   });
 
   return (
-    <div
-      className="align-items-center methodComponent"
-      id={parentPath.concat('.' + name)}>
+    <div className="align-items-center methodComponent" id={id}>
       {process.env.NODE_ENV === 'development' && (
         <p>Render count: {renderCount.current}</p>
       )}

frontend/src/components/NumberComponent.tsx

@@ -1,8 +1,9 @@
 import React, { useEffect, useRef, useState } from 'react';
 import { Form, InputGroup } from 'react-bootstrap';
-import { emit_update } from '../socket';
+import { setAttribute } from '../socket';
 import { DocStringComponent } from './DocStringComponent';
 import '../App.css';
+import { getIdFromFullAccessPath } from '../utils/stringUtils';
 
 // TODO: add button functionality
 
@@ -22,7 +23,7 @@ interface NumberComponentProps {
     value: number,
     callback?: (ack: unknown) => void
   ) => void;
-  addNotification: (string) => void;
+  addNotification: (message: string) => void;
 }
 
 // TODO: highlight the digit that is being changed by setting both selectionStart and
@@ -30,8 +31,8 @@ interface NumberComponentProps {
 const handleArrowKey = (
   key: string,
   value: string,
-  selectionStart: number,
-  selectionEnd: number
+  selectionStart: number
+  // selectionEnd: number
 ) => {
   // Split the input value into the integer part and decimal part
   const parts = value.split('.');
@@ -124,20 +125,22 @@ export const NumberComponent = React.memo((props: NumberComponentProps) => {
   // If emitUpdate is passed, use this instead of the emit_update from the socket
   // Also used when used with a slider
   const emitUpdate =
-    props.customEmitUpdate !== undefined ? props.customEmitUpdate : emit_update;
+    props.customEmitUpdate !== undefined ? props.customEmitUpdate : setAttribute;
 
   const renderCount = useRef(0);
   // Create a state for the cursor position
   const [cursorPosition, setCursorPosition] = useState(null);
   // Create a state for the input string
   const [inputString, setInputString] = useState(props.value.toString());
+  const fullAccessPath = parentPath.concat('.' + name);
+  const id = getIdFromFullAccessPath(fullAccessPath);
 
   useEffect(() => {
     renderCount.current++;
 
     // Set the cursor position after the component re-renders
     const inputElement = document.getElementsByName(
-      parentPath.concat(name)
+      fullAccessPath
     )[0] as HTMLInputElement;
     if (inputElement && cursorPosition !== null) {
       inputElement.setSelectionRange(cursorPosition, cursorPosition);
@@ -214,6 +217,16 @@ export const NumberComponent = React.memo((props: NumberComponentProps) => {
       // Select everything when pressing Ctrl + a
       target.setSelectionRange(0, target.value.length);
       return;
+    } else if (key === '-') {
+      if (selectionStart === 0 && !value.startsWith('-')) {
+        newValue = '-' + value;
+        selectionStart++;
+      } else if (value.startsWith('-') && selectionStart === 1) {
+        newValue = value.substring(1); // remove minus sign
+        selectionStart--;
+      } else {
+        return; // Ignore "-" pressed in other positions
+      }
     } else if (!isNaN(key) && key !== ' ') {
       // Check if a number key or a decimal point key is pressed
       ({ value: newValue, selectionStart } = handleNumericKey(
@@ -233,8 +246,8 @@ export const NumberComponent = React.memo((props: NumberComponentProps) => {
       ({ value: newValue, selectionStart } = handleArrowKey(
         key,
         value,
-        selectionStart,
-        selectionEnd
+        selectionStart
+        // selectionEnd
       ));
     } else if (key === 'Backspace') {
       ({ value: newValue, selectionStart } = handleBackspaceKey(
@@ -275,7 +288,7 @@ export const NumberComponent = React.memo((props: NumberComponentProps) => {
   };
 
   return (
-    <div className="numberComponent" id={parentPath.concat('.' + name)}>
+    <div className="numberComponent" id={id}>
       {process.env.NODE_ENV === 'development' && showName && (
         <p>Render count: {renderCount.current}</p>
       )}
@@ -287,7 +300,7 @@ export const NumberComponent = React.memo((props: NumberComponentProps) => {
             type="text"
             value={inputString}
             disabled={readOnly}
-            name={parentPath.concat(name)}
+            name={fullAccessPath}
             onKeyDown={handleKeyDown}
             onBlur={handleBlur}
             className={isInstantUpdate && !readOnly ? 'instantUpdate' : ''}

frontend/src/components/SliderComponent.tsx

@@ -1,9 +1,10 @@
 import React, { useEffect, useRef, useState } from 'react';
 import { InputGroup, Form, Row, Col, Collapse, ToggleButton } from 'react-bootstrap';
-import { emit_update } from '../socket';
+import { setAttribute } from '../socket';
 import { DocStringComponent } from './DocStringComponent';
 import { Slider } from '@mui/material';
 import { NumberComponent } from './NumberComponent';
+import { getIdFromFullAccessPath } from '../utils/stringUtils';
 
 interface SliderComponentProps {
   name: string;
@@ -15,17 +16,12 @@ interface SliderComponentProps {
   docString: string;
   stepSize: number;
   isInstantUpdate: boolean;
-  addNotification: (string) => void;
+  addNotification: (message: string) => void;
 }
 
 export const SliderComponent = React.memo((props: SliderComponentProps) => {
   const renderCount = useRef(0);
   const [open, setOpen] = useState(false);
-
-  useEffect(() => {
-    renderCount.current++;
-  });
-
   const {
     name,
     parentPath,
@@ -38,6 +34,12 @@ export const SliderComponent = React.memo((props: SliderComponentProps) => {
     isInstantUpdate,
     addNotification
   } = props;
+  const fullAccessPath = parentPath.concat('.' + name);
+  const id = getIdFromFullAccessPath(fullAccessPath);
+
+  useEffect(() => {
+    renderCount.current++;
+  });
 
   useEffect(() => {
     addNotification(`${parentPath}.${name} changed to ${value}.`);
@@ -64,7 +66,7 @@ export const SliderComponent = React.memo((props: SliderComponentProps) => {
     max: number = props.max,
     stepSize: number = props.stepSize
   ) => {
-    emit_update(
+    setAttribute(
       name,
       parentPath,
       {
@@ -102,7 +104,7 @@ export const SliderComponent = React.memo((props: SliderComponentProps) => {
   };
 
   return (
-    <div className="sliderComponent" id={parentPath.concat('.' + name)}>
+    <div className="sliderComponent" id={id}>
       {process.env.NODE_ENV === 'development' && (
         <p>Render count: {renderCount.current}</p>
       )}
@@ -145,6 +147,7 @@ export const SliderComponent = React.memo((props: SliderComponentProps) => {
         </Col>
         <Col xs="auto">
           <ToggleButton
+            id={`button-${id}`}
             onClick={() => setOpen(!open)}
             type="checkbox"
             checked={open}

frontend/src/components/StringComponent.tsx

@@ -1,8 +1,9 @@
 import React, { useEffect, useRef, useState } from 'react';
 import { Form, InputGroup } from 'react-bootstrap';
-import { emit_update } from '../socket';
+import { setAttribute } from '../socket';
 import { DocStringComponent } from './DocStringComponent';
 import '../App.css';
+import { getIdFromFullAccessPath } from '../utils/stringUtils';
 
 // TODO: add button functionality
 
@@ -13,7 +14,7 @@ interface StringComponentProps {
   readOnly: boolean;
   docString: string;
   isInstantUpdate: boolean;
-  addNotification: (string) => void;
+  addNotification: (message: string) => void;
 }
 
 export const StringComponent = React.memo((props: StringComponentProps) => {
@@ -22,6 +23,8 @@ export const StringComponent = React.memo((props: StringComponentProps) => {
 
   const renderCount = useRef(0);
   const [inputString, setInputString] = useState(props.value);
+  const fullAccessPath = parentPath.concat('.' + name);
+  const id = getIdFromFullAccessPath(fullAccessPath);
 
   useEffect(() => {
     renderCount.current++;
@@ -38,24 +41,24 @@ export const StringComponent = React.memo((props: StringComponentProps) => {
   const handleChange = (event) => {
     setInputString(event.target.value);
     if (isInstantUpdate) {
-      emit_update(name, parentPath, event.target.value);
+      setAttribute(name, parentPath, event.target.value);
     }
   };
 
   const handleKeyDown = (event) => {
     if (event.key === 'Enter' && !isInstantUpdate) {
-      emit_update(name, parentPath, inputString);
+      setAttribute(name, parentPath, inputString);
     }
   };
 
   const handleBlur = () => {
     if (!isInstantUpdate) {
-      emit_update(name, parentPath, inputString);
+      setAttribute(name, parentPath, inputString);
     }
   };
 
   return (
-    <div className={'stringComponent'} id={parentPath.concat(name)}>
+    <div className={'stringComponent'} id={id}>
       {process.env.NODE_ENV === 'development' && (
         <p>Render count: {renderCount.current}</p>
       )}

frontend/src/socket.ts

@@ -9,15 +9,28 @@ console.debug('Websocket: ', URL);
 
 export const socket = io(URL, { path: '/ws/socket.io', transports: ['websocket'] });
 
-export const emit_update = (
+export const setAttribute = (
   name: string,
   parentPath: string,
   value: unknown,
   callback?: (ack: unknown) => void
 ) => {
   if (callback) {
-    socket.emit('frontend_update', { name, parent_path: parentPath, value }, callback);
+    socket.emit('set_attribute', { name, parent_path: parentPath, value }, callback);
   } else {
-    socket.emit('frontend_update', { name, parent_path: parentPath, value });
+    socket.emit('set_attribute', { name, parent_path: parentPath, value });
+  }
+};
+
+export const runMethod = (
+  name: string,
+  parentPath: string,
+  kwargs: Record<string, unknown>,
+  callback?: (ack: unknown) => void
+) => {
+  if (callback) {
+    socket.emit('run_method', { name, parent_path: parentPath, kwargs }, callback);
+  } else {
+    socket.emit('run_method', { name, parent_path: parentPath, kwargs });
   }
 };

frontend/src/utils/stringUtils.ts

@@ -0,0 +1,12 @@
+export function getIdFromFullAccessPath(fullAccessPath: string) {
+  // Replace '].' with a single dash
+  let id = fullAccessPath.replace(/\]\./g, '-');
+
+  // Replace any character that is not a word character or underscore with a dash
+  id = id.replace(/[^\w_]+/g, '-');
+
+  // Remove any trailing dashes
+  id = id.replace(/-+$/, '');
+
+  return id;
+}

mkdocs.yml

@@ -0,0 +1,41 @@
+site_name: pydase Documentation
+repo_url: https://github.com/tiqi-group/pydase
+edit_uri: blob/docs/docs/
+nav:
+  - Home: index.md
+  - Getting Started: getting-started.md
+  - User Guide: 
+    - Components Guide: user-guide/Components.md
+  - Developer Guide: 
+    - Developer Guide: dev-guide/README.md
+    - API Reference: dev-guide/api.md
+    - Adding Components: dev-guide/Adding_Components.md
+  - About:
+    - Release Notes: about/release-notes.md
+    - Contributing: about/contributing.md
+    - License: about/license.md
+
+theme: readthedocs
+
+extra_css:
+  - css/extra.css
+
+markdown_extensions:
+  - smarty
+  - toc:
+      permalink: true
+  - pymdownx.highlight:
+      anchor_linenums: true
+  - pymdownx.snippets
+  - pymdownx.superfences
+  # - pymdownx.highlight:
+  # - pymdownx.inlinehilite
+
+
+plugins:
+  - include-markdown
+  - search
+  - mkdocstrings
+
+watch:
+  - src/pydase

poetry.toml

@@ -1,3 +1,2 @@
 [virtualenvs]
 in-project = true
-prefer-active-python = true

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "pydase"
-version = "0.1.0"
+version = "0.3.0"
 description = "A flexible and robust Python library for creating, managing, and interacting with data services, with built-in support for web and RPC servers, and customizable features for diverse use cases."
 authors = ["Mose Mueller <mosmuell@ethz.ch>"]
 readme = "README.md"
@@ -8,9 +8,8 @@ packages = [{ include = "pydase", from = "src" }]
 
 
 [tool.poetry.dependencies]
-python = "^3.9"
+python = "^3.10"
 rpyc = "^5.3.1"
-loguru = "^0.7.0"
 fastapi = "^0.100.0"
 uvicorn = "^0.22.0"
 toml = "^0.10.2"
@@ -36,18 +35,27 @@ flake8-pep604 = "^0.1.0"
 flake8-eradicate = "^1.4.0"
 matplotlib = "^3.7.2"
 pyright = "^1.1.323"
+pytest-mock = "^3.11.1"
+
+
+[tool.poetry.group.docs.dependencies]
+mkdocs = "^1.5.2"
+mkdocs-include-markdown-plugin = "^3.9.1"
+mkdocstrings = "^0.22.0"
+pymdown-extensions = "^10.1"
 
 [build-system]
 requires = ["poetry-core"]
 build-backend = "poetry.core.masonry.api"
 
 [tool.pyright]
-include = ["src/pydase", "tests"]
-exclude = ["**/node_modules", "**/__pycache__", "docs", "frontend"]
+include = ["src/pydase"]
+exclude = ["**/node_modules", "**/__pycache__", "docs", "frontend", "tests"]
 venvPath = "."
 venv = ".venv"
 typeCheckingMode = "basic"
 reportUnknownMemberType = true
+reportUnknownParameterType = true
 
 [tool.black]
 line-length = 88

src/pydase/components/__init__.py

@@ -27,10 +27,12 @@ print(my_service.voltage.value)  # Output: 5
 ```
 """
 
+from pydase.components.coloured_enum import ColouredEnum
 from pydase.components.image import Image
 from pydase.components.number_slider import NumberSlider
 
 __all__ = [
     "NumberSlider",
     "Image",
+    "ColouredEnum",
 ]

src/pydase/components/coloured_enum.py

@@ -0,0 +1,61 @@
+from enum import Enum
+
+
+class ColouredEnum(Enum):
+    """
+    Represents a UI element that can display colour-coded text based on its value.
+
+    This class extends the standard Enum but requires its values to be valid CSS
+    colour codes. Supported colour formats include:
+        - Hexadecimal colours
+        - Hexadecimal colours with transparency
+        - RGB colours
+        - RGBA colours
+        - HSL colours
+        - HSLA colours
+        - Predefined/Cross-browser colour names
+    Refer to the this website for more details on colour formats:
+    (https://www.w3schools.com/cssref/css_colours_legal.php)
+
+    The behavior of this component in the UI depends on how it's defined in the data
+    service:
+        - As property with a setter or as attribute: Renders as a dropdown menu,
+            allowing users to select and change its value from the frontend.
+        - As property without a setter: Displays as a coloured box with the key of the
+            `ColouredEnum` as text inside, serving as a visual indicator without user
+            interaction.
+
+    Example:
+    --------
+    ```python
+    import pydase.components as pyc
+    import pydase
+
+    class MyStatus(pyc.ColouredEnum):
+        PENDING = "#FFA500"  # Orange
+        RUNNING = "#0000FF80"  # Transparent Blue
+        PAUSED = "rgb(169, 169, 169)"  # Dark Gray
+        RETRYING = "rgba(255, 255, 0, 0.3)"  # Transparent Yellow
+        COMPLETED = "hsl(120, 100%, 50%)"  # Green
+        FAILED = "hsla(0, 100%, 50%, 0.7)"  # Transparent Red
+        CANCELLED = "SlateGray"  # Slate Gray
+
+    class StatusExample(pydase.DataService):
+        _status = MyStatus.RUNNING
+
+        @property
+        def status(self) -> MyStatus:
+            return self._status
+
+        @status.setter
+        def status(self, value: MyStatus) -> None:
+            # Custom logic here...
+            self._status = value
+
+    # Example usage:
+    my_service = StatusExample()
+    my_service.status = MyStatus.FAILED
+    ```
+    """
+
+    pass

src/pydase/components/image.py

@@ -1,17 +1,19 @@
 import base64
 import io
+import logging
 from pathlib import Path
-from typing import TYPE_CHECKING, Optional, Union
+from typing import TYPE_CHECKING, Optional
 from urllib.request import urlopen
 
-import PIL.Image
-from loguru import logger
+import PIL.Image  # type: ignore
 
 from pydase.data_service.data_service import DataService
 
 if TYPE_CHECKING:
     from matplotlib.figure import Figure
 
+logger = logging.getLogger(__name__)
+
 
 class Image(DataService):
     def __init__(
@@ -29,7 +31,7 @@ class Image(DataService):
     def format(self) -> str:
         return self._format
 
-    def load_from_path(self, path: Union[Path, str]) -> None:
+    def load_from_path(self, path: Path | str) -> None:
         with PIL.Image.open(path) as image:
             self._load_from_PIL(image)
 
@@ -54,7 +56,7 @@ class Image(DataService):
         self._load_from_base64(value_, format_)
 
     def _load_from_base64(self, value_: bytes, format_: str) -> None:
-        value = value_.decode("utf-8") if isinstance(value_, bytes) else value_
+        value = value_.decode("utf-8")
         self._value = value
         self._format = format_
 
@@ -68,7 +70,7 @@ class Image(DataService):
         else:
             logger.error("Image format is 'None'. Skipping...")
 
-    def _get_image_format_from_bytes(self, value_: bytes) -> Union[str, None]:
+    def _get_image_format_from_bytes(self, value_: bytes) -> str | None:
         image_data = base64.b64decode(value_)
         # Create a writable memory buffer for the image
         image_buffer = io.BytesIO(image_data)

src/pydase/components/number_slider.py

@@ -1,9 +1,10 @@
-from typing import Any, Literal, Union
-
-from loguru import logger
+import logging
+from typing import Any, Literal
 
 from pydase.data_service.data_service import DataService
 
+logger = logging.getLogger(__name__)
+
 
 class NumberSlider(DataService):
     """
@@ -39,11 +40,11 @@ class NumberSlider(DataService):
 
     def __init__(
         self,
-        value: Union[float, int] = 0,
+        value: float | int = 0,
         min: float = 0.0,
         max: float = 100.0,
-        step_size: Union[float, int] = 1.0,
-        type: Union[Literal["int"], Literal["float"]] = "float",
+        step_size: float | int = 1.0,
+        type: Literal["int"] | Literal["float"] = "float",
     ) -> None:
         if type not in {"float", "int"}:
             logger.error(f"Unknown type '{type}'. Using 'float'.")

src/pydase/config.py

@@ -1,9 +1,9 @@
-from typing import Literal, Union
+from typing import Literal
 
 from confz import BaseConfig, EnvSource
 
 
 class OperationMode(BaseConfig):  # type: ignore
-    environment: Union[Literal["development"], Literal["production"]] = "development"
+    environment: Literal["development"] | Literal["production"] = "development"
 
     CONFIG_SOURCES = EnvSource(allow=["ENVIRONMENT"])

src/pydase/data_service/abstract_data_service.py

@@ -4,9 +4,9 @@ from abc import ABC
 from typing import TYPE_CHECKING, Any
 
 if TYPE_CHECKING:
-    from .callback_manager import CallbackManager
-    from .data_service import DataService
-    from .task_manager import TaskManager
+    from pydase.data_service.callback_manager import CallbackManager
+    from pydase.data_service.data_service import DataService
+    from pydase.data_service.task_manager import TaskManager
 
 
 class AbstractDataService(ABC):

src/pydase/data_service/callback_manager.py

@@ -1,10 +1,9 @@
 from __future__ import annotations
 
 import inspect
+import logging
 from collections.abc import Callable
-from typing import TYPE_CHECKING, Any, Union
-
-from loguru import logger
+from typing import TYPE_CHECKING, Any, cast
 
 from pydase.data_service.abstract_data_service import AbstractDataService
 from pydase.utils.helpers import get_class_and_instance_attributes
@@ -14,6 +13,8 @@ from .data_service_list import DataServiceList
 if TYPE_CHECKING:
     from .data_service import DataService
 
+logger = logging.getLogger(__name__)
+
 
 class CallbackManager:
     _notification_callbacks: list[Callable[[str, str, Any], Any]] = []
@@ -55,9 +56,10 @@ class CallbackManager:
         self, obj: "AbstractDataService", parent_path: str
     ) -> None:
         """
-        This method ensures that notifications are emitted whenever a list attribute of
-        a DataService instance changes. These notifications pertain solely to the list
-        item changes, not to changes in attributes of objects within the list.
+        This method ensures that notifications are emitted whenever a public list
+        attribute of a DataService instance changes. These notifications pertain solely
+        to the list item changes, not to changes in attributes of objects within the
+        list.
 
         The method works by converting all list attributes (both at the class and
         instance levels) into DataServiceList objects. Each DataServiceList is then
@@ -101,6 +103,8 @@ class CallbackManager:
                         value=value,
                     )
                     if self.service == self.service.__root__
+                    # Skip private and protected lists
+                    and not cast(str, attr_name).startswith("_")
                     else None
                 )
 
@@ -109,9 +113,12 @@ class CallbackManager:
                     attr_value.add_callback(callback)
                     continue
                 if id(attr_value) in self._list_mapping:
+                    # If the list `attr_value` was already referenced somewhere else
                     notifying_list = self._list_mapping[id(attr_value)]
                     notifying_list.add_callback(callback)
                 else:
+                    # convert the builtin list into a DataServiceList and add the
+                    # callback
                     notifying_list = DataServiceList(attr_value, callback=[callback])
                     self._list_mapping[id(attr_value)] = notifying_list
 
@@ -206,8 +213,8 @@ class CallbackManager:
 
     def __register_recursive_parameter_callback(
         self,
-        obj: Union["AbstractDataService", DataServiceList],
-        callback: Callable[[Union[str, int], Any], None],
+        obj: "AbstractDataService | DataServiceList",
+        callback: Callable[[str | int, Any], None],
     ) -> None:
         """
         Register callback to a DataService or DataServiceList instance and its nested
@@ -222,7 +229,7 @@ class CallbackManager:
         if isinstance(obj, DataServiceList):
             # emits callback when item in list gets reassigned
             obj.add_callback(callback=callback)
-            obj_list: Union[DataServiceList, list[AbstractDataService]] = obj
+            obj_list: DataServiceList | list[AbstractDataService] = obj
         else:
             obj_list = [obj]
 
@@ -337,7 +344,7 @@ class CallbackManager:
 
         # Create and register a callback for the object
         # only emit the notification when the call was registered by the root object
-        callback: Callable[[str, Union[dict[str, Any], None]], None] = (
+        callback: Callable[[str, dict[str, Any] | None], None] = (
             lambda name, status: obj._callback_manager.emit_notification(
                 parent_path=parent_path, name=name, value=status
             )
@@ -352,6 +359,12 @@ class CallbackManager:
         attrs: dict[str, Any] = get_class_and_instance_attributes(obj)
 
         for nested_attr_name, nested_attr in attrs.items():
+            if isinstance(nested_attr, DataServiceList):
+                for i, item in enumerate(nested_attr):
+                    if isinstance(item, AbstractDataService):
+                        self._register_start_stop_task_callbacks(
+                            item, parent_path=f"{parent_path}.{nested_attr_name}[{i}]"
+                        )
             if isinstance(nested_attr, AbstractDataService):
                 self._register_start_stop_task_callbacks(
                     nested_attr, parent_path=f"{parent_path}.{nested_attr_name}"

src/pydase/data_service/data_service.py

@@ -1,12 +1,10 @@
-import asyncio
-import inspect
-import json
-import os
+import logging
+import warnings
 from enum import Enum
-from typing import Any, Optional, cast, get_type_hints
+from pathlib import Path
+from typing import Any, Optional, get_type_hints
 
-import rpyc
-from loguru import logger
+import rpyc  # type: ignore
 
 import pydase.units as u
 from pydase.data_service.abstract_data_service import AbstractDataService
@@ -14,19 +12,23 @@ from pydase.data_service.callback_manager import CallbackManager
 from pydase.data_service.task_manager import TaskManager
 from pydase.utils.helpers import (
     convert_arguments_to_hinted_types,
-    generate_paths_from_DataService_dict,
     get_class_and_instance_attributes,
-    get_component_class_names,
-    get_nested_value_from_DataService_by_path_and_key,
-    get_object_attr_from_path,
+    get_object_attr_from_path_list,
     is_property_attribute,
     parse_list_attr_and_index,
     update_value_if_changed,
 )
+from pydase.utils.serializer import (
+    Serializer,
+    generate_serialized_data_paths,
+    get_nested_dict_by_path,
+)
 from pydase.utils.warnings import (
     warn_if_instance_class_does_not_inherit_from_DataService,
 )
 
+logger = logging.getLogger(__name__)
+
 
 def process_callable_attribute(attr: Any, args: dict[str, Any]) -> Any:
     converted_args_or_error_msg = convert_arguments_to_hinted_types(
@@ -40,7 +42,7 @@ def process_callable_attribute(attr: Any, args: dict[str, Any]) -> Any:
 
 
 class DataService(rpyc.Service, AbstractDataService):
-    def __init__(self, filename: Optional[str] = None) -> None:
+    def __init__(self, **kwargs: Any) -> None:
         self._callback_manager: CallbackManager = CallbackManager(self)
         self._task_manager = TaskManager(self)
 
@@ -49,14 +51,21 @@ class DataService(rpyc.Service, AbstractDataService):
 
         self.__root__: "DataService" = self
         """Keep track of the root object. This helps to filter the emission of
-        notifications. This overwrite the TaksManager's __root__ attribute."""
+        notifications."""
 
-        self._filename: Optional[str] = filename
+        filename = kwargs.pop("filename", None)
+        if filename is not None:
+            warnings.warn(
+                "The 'filename' argument is deprecated and will be removed in a future version. "
+                "Please pass the 'filename' argument to `pydase.Server`.",
+                DeprecationWarning,
+                stacklevel=2,
+            )
+            self._filename: str | Path = filename
 
         self._callback_manager.register_callbacks()
         self.__check_instance_classes()
         self._initialised = True
-        self._load_values_from_json()
 
     def __setattr__(self, __name: str, __value: Any) -> None:
         # converting attributes that are not properties
@@ -83,8 +92,9 @@ class DataService(rpyc.Service, AbstractDataService):
 
     def __check_instance_classes(self) -> None:
         for attr_name, attr_value in get_class_and_instance_attributes(self).items():
-            # every class defined by the user should inherit from DataService
-            if not attr_name.startswith("_DataService__"):
+            # every class defined by the user should inherit from DataService if it is
+            # assigned to a public attribute
+            if not attr_name.startswith("_"):
                 warn_if_instance_class_does_not_inherit_from_DataService(attr_value)
 
     def __set_attribute_based_on_type(  # noqa:CFQ002
@@ -128,50 +138,44 @@ class DataService(rpyc.Service, AbstractDataService):
         # allow all other attributes
         setattr(self, name, value)
 
-    def _load_values_from_json(self) -> None:
-        if self._filename is not None:
-            # Check if the file specified by the filename exists
-            if os.path.exists(self._filename):
-                with open(self._filename, "r") as f:
-                    # Load JSON data from file and update class attributes with these
-                    # values
-                    self.load_DataService_from_JSON(cast(dict[str, Any], json.load(f)))
-
     def write_to_file(self) -> None:
         """
         Serialize the DataService instance and write it to a JSON file.
 
-        Args:
-            filename (str): The name of the file to write to.
+        This method is deprecated and will be removed in a future version.
+        Service persistence is handled by `pydase.Server` now, instead.
         """
-        if self._filename is not None:
-            with open(self._filename, "w") as f:
-                json.dump(self.serialize(), f, indent=4)
-        else:
-            logger.error(
-                f"Class {self.__class__.__name__} was not initialised with a filename. "
-                'Skipping "write_to_file"...'
-            )
+
+        warnings.warn(
+            "'write_to_file' is deprecated and will be removed in a future version. "
+            "Service persistence is handled by `pydase.Server` now, instead.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+
+        if hasattr(self, "_state_manager"):
+            getattr(self, "_state_manager").save_state()
 
     def load_DataService_from_JSON(self, json_dict: dict[str, Any]) -> None:
+        warnings.warn(
+            "'load_DataService_from_JSON' is deprecated and will be removed in a "
+            "future version. "
+            "Service persistence is handled by `pydase.Server` now, instead.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+
         # Traverse the serialized representation and set the attributes of the class
         serialized_class = self.serialize()
-        for path in generate_paths_from_DataService_dict(json_dict):
-            value = get_nested_value_from_DataService_by_path_and_key(
-                json_dict, path=path
-            )
-            value_type = get_nested_value_from_DataService_by_path_and_key(
-                json_dict, path=path, key="type"
-            )
-            class_value_type = get_nested_value_from_DataService_by_path_and_key(
-                serialized_class, path=path, key="type"
-            )
+        for path in generate_serialized_data_paths(json_dict):
+            nested_json_dict = get_nested_dict_by_path(json_dict, path)
+            value = nested_json_dict["value"]
+            value_type = nested_json_dict["type"]
+
+            nested_class_dict = get_nested_dict_by_path(serialized_class, path)
+            class_value_type = nested_class_dict.get("type", None)
             if class_value_type == value_type:
-                class_attr_is_read_only = (
-                    get_nested_value_from_DataService_by_path_and_key(
-                        serialized_class, path=path, key="readonly"
-                    )
-                )
+                class_attr_is_read_only = nested_class_dict["readonly"]
                 if class_attr_is_read_only:
                     logger.debug(
                         f'Attribute "{path}" is read-only. Ignoring value from JSON '
@@ -182,6 +186,10 @@ class DataService(rpyc.Service, AbstractDataService):
                 parts = path.split(".")
                 attr_name = parts[-1]
 
+                # Convert dictionary into Quantity
+                if class_value_type == "Quantity":
+                    value = u.convert_to_quantity(value)
+
                 self.update_DataService_attribute(parts[:-1], attr_name, value)
             else:
                 logger.info(
@@ -198,161 +206,15 @@ class DataService(rpyc.Service, AbstractDataService):
         value, readonly status, and documentation if any in the resulting dictionary.
         Attributes and methods starting with an underscore are ignored.
 
-        For attributes, methods, and properties unique to the class (not inherited from
-        the base class), the method uses the format "<prefix>.<key>" for keys in the
-        dictionary. If no prefix is provided, the key format is simply "<key>".
-
-        For nested DataService instances, the method serializes recursively and appends
-        the key of the nested instance to the prefix in the format "<prefix>.<key>".
-
+        For nested DataService instances, the method serializes recursively.
         For attributes of type list, each item in the list is serialized individually.
         If an item in the list is an instance of DataService, it is serialized
-        recursively with its key in the format "<prefix>.<key>.<item_id>", where
-        "item_id" is the id of the item itself.
-
-        Args:
-            prefix (str, optional): The prefix for each key in the serialized
-            dictionary. This is mainly used when this method is called recursively to
-            maintain the structure of nested instances.
+        recursively.
 
         Returns:
             dict: The serialized instance.
         """
-        result: dict[str, dict[str, Any]] = {}
-
-        # Get the dictionary of the base class
-        base_set = set(type(super()).__dict__)
-        # Get the dictionary of the derived class
-        derived_set = set(type(self).__dict__)
-        # Get the difference between the two dictionaries
-        derived_only_set = derived_set - base_set
-
-        instance_dict = set(self.__dict__)
-        # Merge the class and instance dictionaries
-        merged_set = derived_only_set | instance_dict
-
-        def get_attribute_doc(attr: Any) -> Optional[str]:
-            """This function takes an input attribute attr and returns its documentation
-            string if it's different from the documentation of its type, otherwise,
-            it returns None.
-            """
-            attr_doc = inspect.getdoc(attr)
-            attr_class_doc = inspect.getdoc(type(attr))
-            if attr_class_doc != attr_doc:
-                return attr_doc
-            else:
-                return None
-
-        # Iterate over attributes, properties, class attributes, and methods
-        for key in sorted(merged_set):
-            if key.startswith("_"):
-                continue  # Skip attributes that start with underscore
-
-            # Skip keys that start with "start_" or "stop_" and end with an async method
-            # name
-            if (key.startswith("start_") or key.startswith("stop_")) and key.split(
-                "_", 1
-            )[1] in {
-                name
-                for name, _ in inspect.getmembers(
-                    self, predicate=inspect.iscoroutinefunction
-                )
-            }:
-                continue
-
-            # Get the value of the current attribute or method
-            value = getattr(self, key)
-
-            if isinstance(value, DataService):
-                result[key] = {
-                    "type": type(value).__name__
-                    if type(value).__name__ in get_component_class_names()
-                    else "DataService",
-                    "value": value.serialize(),
-                    "readonly": False,
-                    "doc": get_attribute_doc(value),
-                }
-            elif isinstance(value, list):
-                result[key] = {
-                    "type": "list",
-                    "value": [
-                        {
-                            "type": type(item).__name__
-                            if not isinstance(item, DataService)
-                            or type(item).__name__ in get_component_class_names()
-                            else "DataService",
-                            "value": item.serialize()
-                            if isinstance(item, DataService)
-                            else item,
-                            "readonly": False,
-                            "doc": get_attribute_doc(value),
-                        }
-                        for item in value
-                    ],
-                    "readonly": False,
-                }
-            elif inspect.isfunction(value) or inspect.ismethod(value):
-                sig = inspect.signature(value)
-
-                # Store parameters and their anotations in a dictionary
-                parameters: dict[str, Optional[str]] = {}
-                for k, v in sig.parameters.items():
-                    annotation = v.annotation
-                    if annotation is not inspect._empty:
-                        if isinstance(annotation, type):
-                            # Handle regular types
-                            parameters[k] = annotation.__name__
-                        else:
-                            parameters[k] = str(annotation)
-                    else:
-                        parameters[k] = None
-                running_task_info = None
-                if (
-                    key in self._task_manager.tasks
-                ):  # If there's a running task for this method
-                    task_info = self._task_manager.tasks[key]
-                    running_task_info = task_info["kwargs"]
-
-                result[key] = {
-                    "type": "method",
-                    "async": asyncio.iscoroutinefunction(value),
-                    "parameters": parameters,
-                    "doc": get_attribute_doc(value),
-                    "readonly": True,
-                    "value": running_task_info,
-                }
-            elif isinstance(getattr(self.__class__, key, None), property):
-                prop: property = getattr(self.__class__, key)
-                result[key] = {
-                    "type": type(value).__name__,
-                    "value": value
-                    if not isinstance(value, u.Quantity)
-                    else {"magnitude": value.m, "unit": str(value.u)},
-                    "readonly": prop.fset is None,
-                    "doc": get_attribute_doc(prop),
-                }
-            elif isinstance(value, Enum):
-                result[key] = {
-                    "type": "Enum",
-                    "value": value.name,
-                    "enum": {
-                        name: member.value
-                        for name, member in value.__class__.__members__.items()
-                    },
-                    "readonly": False,
-                    "doc": get_attribute_doc(value),
-                }
-            else:
-                result[key] = {
-                    "type": type(value).__name__,
-                    "value": value
-                    if not isinstance(value, u.Quantity)
-                    else {"magnitude": value.m, "unit": str(value.u)},
-                    "readonly": False,
-                    "doc": get_attribute_doc(value),
-                }
-
-        return result
+        return Serializer.serialize_object(self)["value"]
 
     def update_DataService_attribute(
         self,
@@ -360,10 +222,19 @@ class DataService(rpyc.Service, AbstractDataService):
         attr_name: str,
         value: Any,
     ) -> None:
+        warnings.warn(
+            "'update_DataService_attribute' is deprecated and will be removed in a "
+            "future version. "
+            "Service state management is handled by `pydase.data_service.state_manager`"
+            "now, instead.",
+            DeprecationWarning,
+            stacklevel=2,
+        )
+
         # If attr_name corresponds to a list entry, extract the attr_name and the index
         attr_name, index = parse_list_attr_and_index(attr_name)
         # Traverse the object according to the path parts
-        target_obj = get_object_attr_from_path(self, path_list)
+        target_obj = get_object_attr_from_path_list(self, path_list)
 
         # If the attribute is a property, change it using the setter without getting the
         # property value (would otherwise be bad for expensive getter methods)
@@ -371,7 +242,7 @@ class DataService(rpyc.Service, AbstractDataService):
             setattr(target_obj, attr_name, value)
             return
 
-        attr = get_object_attr_from_path(target_obj, [attr_name])
+        attr = get_object_attr_from_path_list(target_obj, [attr_name])
         if attr is None:
             return
 

src/pydase/data_service/data_service_cache.py

@@ -0,0 +1,35 @@
+import logging
+from typing import TYPE_CHECKING, Any
+
+from pydase.utils.serializer import set_nested_value_by_path
+
+if TYPE_CHECKING:
+    from pydase import DataService
+
+logger = logging.getLogger(__name__)
+
+
+class DataServiceCache:
+    def __init__(self, service: "DataService") -> None:
+        self._cache: dict[str, Any] = {}
+        self.service = service
+        self._initialize_cache()
+
+    @property
+    def cache(self) -> dict[str, Any]:
+        return self._cache
+
+    def _initialize_cache(self) -> None:
+        """Initializes the cache and sets up the callback."""
+        logger.debug("Initializing cache.")
+        self._cache = self.service.serialize()
+        self.service._callback_manager.add_notification_callback(self.update_cache)
+
+    def update_cache(self, parent_path: str, name: str, value: Any) -> None:
+        # Remove the part before the first "." in the parent_path
+        parent_path = ".".join(parent_path.split(".")[1:])
+
+        # Construct the full path
+        full_path = f"{parent_path}.{name}" if parent_path else name
+
+        set_nested_value_by_path(self._cache, full_path, value)

src/pydase/data_service/data_service_list.py

@@ -1,6 +1,7 @@
 from collections.abc import Callable
-from typing import Any, Union
+from typing import Any
 
+import pydase.units as u
 from pydase.utils.warnings import (
     warn_if_instance_class_does_not_inherit_from_DataService,
 )
@@ -31,7 +32,7 @@ class DataServiceList(list):
     def __init__(
         self,
         *args: list[Any],
-        callback: Union[list[Callable[[int, Any], None]], None] = None,
+        callback: list[Callable[[int, Any], None]] | None = None,
         **kwargs: Any,
     ) -> None:
         self.callbacks: list[Callable[[int, Any], None]] = []
@@ -47,6 +48,14 @@ class DataServiceList(list):
         super().__init__(*args, **kwargs)  # type: ignore
 
     def __setitem__(self, key: int, value: Any) -> None:  # type: ignore
+        current_value = self.__getitem__(key)
+
+        # parse ints into floats if current value is a float
+        if isinstance(current_value, float) and isinstance(value, int):
+            value = float(value)
+
+        if isinstance(current_value, u.Quantity):
+            value = u.convert_to_quantity(value, str(current_value.u))
         super().__setitem__(key, value)  # type: ignore
 
         for callback in self.callbacks:

src/pydase/data_service/state_manager.py

@@ -0,0 +1,251 @@
+import json
+import logging
+import os
+from collections.abc import Callable
+from pathlib import Path
+from typing import TYPE_CHECKING, Any, Optional, cast
+
+import pydase.units as u
+from pydase.data_service.data_service_cache import DataServiceCache
+from pydase.utils.helpers import (
+    get_object_attr_from_path_list,
+    parse_list_attr_and_index,
+)
+from pydase.utils.serializer import (
+    dump,
+    generate_serialized_data_paths,
+    get_nested_dict_by_path,
+)
+
+if TYPE_CHECKING:
+    from pydase import DataService
+
+logger = logging.getLogger(__name__)
+
+
+def load_state(func: Callable[..., Any]) -> Callable[..., Any]:
+    """This function should be used as a decorator on property setters to indicate that
+    the value should be loaded from the JSON file.
+
+    Example:
+    >>>     class Service(pydase.DataService):
+    ...         _name = "Service"
+    ...
+    ...         @property
+    ...         def name(self) -> str:
+    ...             return self._name
+    ...
+    ...         @name.setter
+    ...         @load_state
+    ...         def name(self, value: str) -> None:
+    ...             self._name = value
+    """
+
+    func._load_state = True
+    return func
+
+
+def has_load_state_decorator(prop: property):
+    """Determines if the property's setter method is decorated with the `@load_state`
+    decorator.
+    """
+
+    try:
+        return getattr(prop.fset, "_load_state")
+    except AttributeError:
+        return False
+
+
+class StateManager:
+    """
+    Manages the state of a DataService instance, serving as both a cache and a
+    persistence layer. It is designed to provide quick access to the latest known state
+    for newly connecting web clients without the need for expensive property accesses
+    that may involve complex calculations or I/O operations.
+
+    The StateManager listens for state change notifications from the DataService's
+    callback manager and updates its cache accordingly. This cache does not always
+    reflect the most current complex property states but rather retains the value from
+    the last known state, optimizing for performance and reducing the load on the
+    system.
+
+    While the StateManager ensures that the cached state is as up-to-date as possible,
+    it does not autonomously update complex properties of the DataService. Such
+    properties must be updated programmatically, for instance, by invoking specific
+    tasks or methods that trigger the necessary operations to refresh their state.
+
+    The cached state maintained by the StateManager is particularly useful for web
+    clients that connect to the system and need immediate access to the current state of
+    the DataService. By avoiding direct and potentially costly property accesses, the
+    StateManager provides a snapshot of the DataService's state that is sufficiently
+    accurate for initial rendering and interaction.
+
+    Attributes:
+        cache (dict[str, Any]):
+            A dictionary cache of the DataService's state.
+        filename (str):
+            The file name used for storing the DataService's state.
+        service (DataService):
+            The DataService instance whose state is being managed.
+
+    Note:
+        The StateManager's cache updates are triggered by notifications and do not
+        include autonomous updates of complex DataService properties, which must be
+        managed programmatically. The cache serves the purpose of providing immediate
+        state information to web clients, reflecting the state after the last property
+        update.
+    """
+
+    def __init__(self, service: "DataService", filename: Optional[str | Path] = None):
+        self.filename = getattr(service, "_filename", None)
+
+        if filename is not None:
+            if self.filename is not None:
+                logger.warning(
+                    f"Overwriting filename {self.filename!r} with {filename!r}."
+                )
+            self.filename = filename
+
+        self.service = service
+        self._data_service_cache = DataServiceCache(self.service)
+
+    @property
+    def cache(self) -> dict[str, Any]:
+        """Returns the cached DataService state."""
+        return self._data_service_cache.cache
+
+    def save_state(self) -> None:
+        """
+        Saves the DataService's current state to a JSON file defined by `self.filename`.
+        Logs an error if `self.filename` is not set.
+        """
+
+        if self.filename is not None:
+            with open(self.filename, "w") as f:
+                json.dump(self.cache, f, indent=4)
+        else:
+            logger.error(
+                "State manager was not initialised with a filename. Skipping "
+                "'save_state'..."
+            )
+
+    def load_state(self) -> None:
+        """
+        Loads the DataService's state from a JSON file defined by `self.filename`.
+        Updates the service's attributes, respecting type and read-only constraints.
+        """
+
+        # Traverse the serialized representation and set the attributes of the class
+        json_dict = self._get_state_dict_from_JSON_file()
+        if json_dict == {}:
+            logger.debug("Could not load the service state.")
+            return
+
+        for path in generate_serialized_data_paths(json_dict):
+            nested_json_dict = get_nested_dict_by_path(json_dict, path)
+            nested_class_dict = get_nested_dict_by_path(self.cache, path)
+
+            value, value_type = nested_json_dict["value"], nested_json_dict["type"]
+            class_attr_value_type = nested_class_dict.get("type", None)
+
+            if class_attr_value_type == value_type:
+                self.set_service_attribute_value_by_path(path, value)
+            else:
+                logger.info(
+                    f"Attribute type of {path!r} changed from {value_type!r} to "
+                    f"{class_attr_value_type!r}. Ignoring value from JSON file..."
+                )
+
+    def _get_state_dict_from_JSON_file(self) -> dict[str, Any]:
+        if self.filename is not None:
+            # Check if the file specified by the filename exists
+            if os.path.exists(self.filename):
+                with open(self.filename, "r") as f:
+                    # Load JSON data from file and update class attributes with these
+                    # values
+                    return cast(dict[str, Any], json.load(f))
+        return {}
+
+    def set_service_attribute_value_by_path(
+        self,
+        path: str,
+        value: Any,
+    ) -> None:
+        """
+        Sets the value of an attribute in the service managed by the `StateManager`
+        given its path as a dot-separated string.
+
+        This method updates the attribute specified by 'path' with 'value' only if the
+        attribute is not read-only and the new value differs from the current one.
+        It also handles type-specific conversions for the new value before setting it.
+
+        Args:
+            path: A dot-separated string indicating the hierarchical path to the
+                attribute.
+            value: The new value to set for the attribute.
+        """
+
+        current_value_dict = get_nested_dict_by_path(self.cache, path)
+
+        # This will also filter out methods as they are 'read-only'
+        if current_value_dict["readonly"]:
+            logger.debug(f"Attribute {path!r} is read-only. Ignoring new value...")
+            return
+
+        converted_value = self.__convert_value_if_needed(value, current_value_dict)
+
+        # only set value when it has changed
+        if self.__attr_value_has_changed(converted_value, current_value_dict["value"]):
+            self.__update_attribute_by_path(path, converted_value)
+        else:
+            logger.debug(f"Value of attribute {path!r} has not changed...")
+
+    def __attr_value_has_changed(self, value_object: Any, current_value: Any) -> bool:
+        """Check if the serialized value of `value_object` differs from `current_value`.
+
+        The method serializes `value_object` to compare it, which is mainly
+        necessary for handling Quantity objects.
+        """
+
+        return dump(value_object)["value"] != current_value
+
+    def __convert_value_if_needed(
+        self, value: Any, current_value_dict: dict[str, Any]
+    ) -> Any:
+        if current_value_dict["type"] == "Quantity":
+            return u.convert_to_quantity(value, current_value_dict["value"]["unit"])
+        return value
+
+    def __update_attribute_by_path(self, path: str, value: Any) -> None:
+        parent_path_list, attr_name = path.split(".")[:-1], path.split(".")[-1]
+
+        # If attr_name corresponds to a list entry, extract the attr_name and the
+        # index
+        attr_name, index = parse_list_attr_and_index(attr_name)
+
+        # Update path to reflect the attribute without list indices
+        path = ".".join([*parent_path_list, attr_name])
+
+        attr_cache_type = get_nested_dict_by_path(self.cache, path)["type"]
+
+        # Traverse the object according to the path parts
+        target_obj = get_object_attr_from_path_list(self.service, parent_path_list)
+
+        if self.__attr_value_should_change(target_obj, attr_name):
+            if attr_cache_type in ("ColouredEnum", "Enum"):
+                enum_attr = get_object_attr_from_path_list(target_obj, [attr_name])
+                setattr(target_obj, attr_name, enum_attr.__class__[value])
+            elif attr_cache_type == "list":
+                list_obj = get_object_attr_from_path_list(target_obj, [attr_name])
+                list_obj[index] = value
+            else:
+                setattr(target_obj, attr_name, value)
+
+    def __attr_value_should_change(self, parent_object: Any, attr_name: str) -> bool:
+        # If the attribute is a property, change it using the setter without getting
+        # the property value (would otherwise be bad for expensive getter methods)
+        prop = getattr(type(parent_object), attr_name, None)
+
+        if isinstance(prop, property):
+            return has_load_state_decorator(prop)
+        return True

src/pydase/data_service/task_manager.py

@@ -2,15 +2,20 @@ from __future__ import annotations
 
 import asyncio
 import inspect
+import logging
 from collections.abc import Callable
 from functools import wraps
-from typing import TYPE_CHECKING, Any, TypedDict, Union
+from typing import TYPE_CHECKING, Any, TypedDict
 
-from loguru import logger
+from pydase.data_service.abstract_data_service import AbstractDataService
+from pydase.data_service.data_service_list import DataServiceList
+from pydase.utils.helpers import get_class_and_instance_attributes
 
 if TYPE_CHECKING:
     from .data_service import DataService
 
+logger = logging.getLogger(__name__)
+
 
 class TaskDict(TypedDict):
     task: asyncio.Task[None]
@@ -82,7 +87,7 @@ class TaskManager:
         """
 
         self.task_status_change_callbacks: list[
-            Callable[[str, Union[dict[str, Any], None]], Any]
+            Callable[[str, dict[str, Any] | None], Any]
         ] = []
         """A list of callback functions to be invoked when the status of a task (start
         or stop) changes."""
@@ -94,92 +99,11 @@ class TaskManager:
         for name, method in inspect.getmembers(
             self.service, predicate=inspect.iscoroutinefunction
         ):
-
-            @wraps(method)
-            def start_task(*args: Any, **kwargs: Any) -> None:
-                def task_done_callback(task: asyncio.Task, name: str) -> None:
-                    """Handles tasks that have finished.
-
-                    Removes a task from the tasks dictionary, calls the defined
-                    callbacks, and logs and re-raises exceptions."""
-
-                    # removing the finished task from the tasks i
-                    self.tasks.pop(name, None)
-
-                    # emit the notification that the task was stopped
-                    for callback in self.task_status_change_callbacks:
-                        callback(name, None)
-
-                    exception = task.exception()
-                    if exception is not None:
-                        # Handle the exception, or you can re-raise it.
-                        logger.error(
-                            f"Task '{name}' encountered an exception: "
-                            f"{type(exception).__name__}: {exception}"
-                        )
-                        raise exception
-
-                async def task(*args: Any, **kwargs: Any) -> None:
-                    try:
-                        await method(*args, **kwargs)
-                    except asyncio.CancelledError:
-                        print(f"Task {name} was cancelled")
-
-                if not self.tasks.get(name):
-                    # Get the signature of the coroutine method to start
-                    sig = inspect.signature(method)
-
-                    # Create a list of the parameter names from the method signature.
-                    parameter_names = list(sig.parameters.keys())
-
-                    # Extend the list of positional arguments with None values to match
-                    # the length of the parameter names list. This is done to ensure
-                    # that zip can pair each parameter name with a corresponding value.
-                    args_padded = list(args) + [None] * (
-                        len(parameter_names) - len(args)
-                    )
-
-                    # Create a dictionary of keyword arguments by pairing the parameter
-                    # names with the values in 'args_padded'. Then merge this dictionary
-                    # with the 'kwargs' dictionary. If a parameter is specified in both
-                    # 'args_padded' and 'kwargs', the value from 'kwargs' is used.
-                    kwargs_updated = {
-                        **dict(zip(parameter_names, args_padded)),
-                        **kwargs,
-                    }
-
-                    # creating the task and adding the task_done_callback which checks
-                    # if an exception has occured during the task execution
-                    task_object = self._loop.create_task(task(*args, **kwargs))
-                    task_object.add_done_callback(
-                        lambda task: task_done_callback(task, name)
-                    )
-
-                    # Store the task and its arguments in the '__tasks' dictionary. The
-                    # key is the name of the method, and the value is a dictionary
-                    # containing the task object and the updated keyword arguments.
-                    self.tasks[name] = {
-                        "task": task_object,
-                        "kwargs": kwargs_updated,
-                    }
-
-                    # emit the notification that the task was started
-                    for callback in self.task_status_change_callbacks:
-                        callback(name, kwargs_updated)
-                else:
-                    logger.error(f"Task `{name}` is already running!")
-
-            def stop_task() -> None:
-                # cancel the task
-                task = self.tasks.get(name, None)
-                if task is not None:
-                    self._loop.call_soon_threadsafe(task["task"].cancel)
-
             # create start and stop methods for each coroutine
-            setattr(self.service, f"start_{name}", start_task)
-            setattr(self.service, f"stop_{name}", stop_task)
+            setattr(self.service, f"start_{name}", self._make_start_task(name, method))
+            setattr(self.service, f"stop_{name}", self._make_stop_task(name))
 
-    def start_autostart_tasks(self) -> None:
+    def _initiate_task_startup(self) -> None:
         if self.service._autostart_tasks is not None:
             for service_name, args in self.service._autostart_tasks.items():
                 start_method = getattr(self.service, f"start_{service_name}", None)
@@ -189,3 +113,123 @@ class TaskManager:
                     logger.warning(
                         f"No start method found for service '{service_name}'"
                     )
+
+    def start_autostart_tasks(self) -> None:
+        self._initiate_task_startup()
+        attrs = get_class_and_instance_attributes(self.service)
+
+        for _, attr_value in attrs.items():
+            if isinstance(attr_value, AbstractDataService):
+                attr_value._task_manager.start_autostart_tasks()
+            elif isinstance(attr_value, DataServiceList):
+                for i, item in enumerate(attr_value):
+                    if isinstance(item, AbstractDataService):
+                        item._task_manager.start_autostart_tasks()
+
+    def _make_stop_task(self, name: str) -> Callable[..., Any]:
+        """
+        Factory function to create a 'stop_task' function for a running task.
+
+        The generated function cancels the associated asyncio task using 'name' for
+        identification, ensuring proper cleanup. Avoids closure and late binding issues.
+
+        Args:
+            name (str): The name of the coroutine task, used for its identification.
+        """
+
+        def stop_task() -> None:
+            # cancel the task
+            task = self.tasks.get(name, None)
+            if task is not None:
+                self._loop.call_soon_threadsafe(task["task"].cancel)
+
+        return stop_task
+
+    def _make_start_task(  # noqa
+        self, name: str, method: Callable[..., Any]
+    ) -> Callable[..., Any]:
+        """
+        Factory function to create a 'start_task' function for a coroutine.
+
+        The generated function starts the coroutine as an asyncio task, handling
+        registration and monitoring.
+        It uses 'name' and 'method' to avoid the closure and late binding issue.
+
+        Args:
+            name (str): The name of the coroutine, used for task management.
+            method (callable): The coroutine to be turned into an asyncio task.
+        """
+
+        @wraps(method)
+        def start_task(*args: Any, **kwargs: Any) -> None:
+            def task_done_callback(task: asyncio.Task[None], name: str) -> None:
+                """Handles tasks that have finished.
+
+                Removes a task from the tasks dictionary, calls the defined
+                callbacks, and logs and re-raises exceptions."""
+
+                # removing the finished task from the tasks i
+                self.tasks.pop(name, None)
+
+                # emit the notification that the task was stopped
+                for callback in self.task_status_change_callbacks:
+                    callback(name, None)
+
+                exception = task.exception()
+                if exception is not None:
+                    # Handle the exception, or you can re-raise it.
+                    logger.error(
+                        f"Task '{name}' encountered an exception: "
+                        f"{type(exception).__name__}: {exception}"
+                    )
+                    raise exception
+
+            async def task(*args: Any, **kwargs: Any) -> None:
+                try:
+                    await method(*args, **kwargs)
+                except asyncio.CancelledError:
+                    logger.info(f"Task {name} was cancelled")
+
+            if not self.tasks.get(name):
+                # Get the signature of the coroutine method to start
+                sig = inspect.signature(method)
+
+                # Create a list of the parameter names from the method signature.
+                parameter_names = list(sig.parameters.keys())
+
+                # Extend the list of positional arguments with None values to match
+                # the length of the parameter names list. This is done to ensure
+                # that zip can pair each parameter name with a corresponding value.
+                args_padded = list(args) + [None] * (len(parameter_names) - len(args))
+
+                # Create a dictionary of keyword arguments by pairing the parameter
+                # names with the values in 'args_padded'. Then merge this dictionary
+                # with the 'kwargs' dictionary. If a parameter is specified in both
+                # 'args_padded' and 'kwargs', the value from 'kwargs' is used.
+                kwargs_updated = {
+                    **dict(zip(parameter_names, args_padded)),
+                    **kwargs,
+                }
+
+                # creating the task and adding the task_done_callback which checks
+                # if an exception has occured during the task execution
+                task_object = self._loop.create_task(task(*args, **kwargs))
+                task_object.add_done_callback(
+                    lambda task: task_done_callback(task, name)
+                )
+
+                # Store the task and its arguments in the '__tasks' dictionary. The
+                # key is the name of the method, and the value is a dictionary
+                # containing the task object and the updated keyword arguments.
+                self.tasks[name] = {
+                    "task": task_object,
+                    "kwargs": kwargs_updated,
+                }
+
+                # emit the notification that the task was started
+                for callback in self.task_status_change_callbacks:
+                    callback(name, kwargs_updated)
+            else:
+                logger.error(f"Task `{name}` is already running!")
+
+        return start_task

src/pydase/frontend/asset-manifest.json

@@ -1,13 +1,13 @@
 {
   "files": {
-    "main.css": "/static/css/main.398bc7f8.css",
-    "main.js": "/static/js/main.c348625e.js",
+    "main.css": "/static/css/main.c444b055.css",
+    "main.js": "/static/js/main.08edc629.js",
     "index.html": "/index.html",
-    "main.398bc7f8.css.map": "/static/css/main.398bc7f8.css.map",
-    "main.c348625e.js.map": "/static/js/main.c348625e.js.map"
+    "main.c444b055.css.map": "/static/css/main.c444b055.css.map",
+    "main.08edc629.js.map": "/static/js/main.08edc629.js.map"
   },
   "entrypoints": [
-    "static/css/main.398bc7f8.css",
-    "static/js/main.c348625e.js"
+    "static/css/main.c444b055.css",
+    "static/js/main.08edc629.js"
   ]
 }

src/pydase/frontend/index.html

@@ -1 +1 @@
-<!doctype html><html lang="en"><head><meta charset="utf-8"/><link rel="icon" href="/favicon.ico"/><meta name="viewport" content="width=device-width,initial-scale=1"/><meta name="theme-color" content="#000000"/><meta name="description" content="Web site displaying a pydase UI."/><link rel="apple-touch-icon" href="/logo192.png"/><link rel="manifest" href="/manifest.json"/><title>pydase App</title><script defer="defer" src="/static/js/main.c348625e.js"></script><link href="/static/css/main.398bc7f8.css" rel="stylesheet"></head><body><noscript>You need to enable JavaScript to run this app.</noscript><div id="root"></div></body></html>
+<!doctype html><html lang="en"><head><meta charset="utf-8"/><link rel="icon" href="/favicon.ico"/><meta name="viewport" content="width=device-width,initial-scale=1"/><meta name="theme-color" content="#000000"/><meta name="description" content="Web site displaying a pydase UI."/><link rel="apple-touch-icon" href="/logo192.png"/><link rel="manifest" href="/manifest.json"/><title>pydase App</title><script defer="defer" src="/static/js/main.08edc629.js"></script><link href="/static/css/main.c444b055.css" rel="stylesheet"></head><body><noscript>You need to enable JavaScript to run this app.</noscript><div id="root"></div></body></html>

src/pydase/frontend/static/js/main.08edc629.js.LICENSE.txt

@@ -45,11 +45,3 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  */
-
-/**
- * @mui/styled-engine v5.13.2
- *
- * @license MIT
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */

src/pydase/server/server.py

@@ -1,26 +1,27 @@
 import asyncio
+import logging
 import os
 import signal
 import threading
 from concurrent.futures import ThreadPoolExecutor
 from enum import Enum
+from pathlib import Path
 from types import FrameType
-from typing import Any, Optional, Protocol, TypedDict, Union
+from typing import Any, Optional, Protocol, TypedDict
 
 import uvicorn
-from loguru import logger
-from rpyc import (
-    ForkingServer,  # can be used for multiprocessing, e.g. a database interface server
-)
-from rpyc import ThreadedServer
+from rpyc import ForkingServer, ThreadedServer  # type: ignore
 from uvicorn.server import HANDLED_SIGNALS
 
 import pydase.units as u
 from pydase import DataService
+from pydase.data_service.state_manager import StateManager
 from pydase.version import __version__
 
 from .web_server import WebAPI
 
+logger = logging.getLogger(__name__)
+
 
 class AdditionalServerProtocol(Protocol):
     """
@@ -28,9 +29,8 @@ class AdditionalServerProtocol(Protocol):
 
     This protocol sets the standard for how additional servers should be implemented
     to ensure compatibility with the main Server class. The protocol requires that
-    any server implementing it should have an __init__ method for initialization, a
-    serve method for starting the server, and an install_signal_handlers method for
-    setting up signal handlers.
+    any server implementing it should have an __init__ method for initialization and a
+    serve method for starting the server.
 
     Parameters:
     -----------
@@ -46,13 +46,22 @@ class AdditionalServerProtocol(Protocol):
         The hostname or IP address at which the server will be hosted. This could be a
         local address (like '127.0.0.1' for localhost) or a public IP address.
 
+    state_manager: StateManager
+        The state manager managing the state cache and persistence of the exposed
+        service.
+
     **kwargs: Any
         Any additional parameters required for initializing the server. These parameters
         are specific to the server's implementation.
     """
 
     def __init__(
-        self, service: DataService, port: int, host: str, **kwargs: Any
+        self,
+        service: DataService,
+        port: int,
+        host: str,
+        state_manager: StateManager,
+        **kwargs: Any,
     ) -> None:
         ...
 
@@ -62,12 +71,6 @@ class AdditionalServerProtocol(Protocol):
         """
         ...
 
-    def install_signal_handlers(self) -> None:
-        """Sets up signal handlers for the server. This method is used to define how the
-        server should respond to various system signals, such as SIGINT and SIGTERM.
-        """
-        ...
-
 
 class AdditionalServer(TypedDict):
     """
@@ -103,9 +106,10 @@ class Server:
         Whether to enable the RPC server. Default is True.
     enable_web: bool
         Whether to enable the web server. Default is True.
+    filename: str | Path | None
+        Filename of the file managing the service state persistence. Defaults to None.
     use_forking_server: bool
-        Whether to use ForkingServer for multiprocessing (e.g. for a database interface
-        server). Default is False.
+        Whether to use ForkingServer for multiprocessing. Default is False.
     web_settings: dict[str, Any]
         Additional settings for the web server. Default is {} (an empty dictionary).
     additional_servers : list[AdditionalServer]
@@ -125,9 +129,15 @@ class Server:
 
         >>>     class MyCustomServer:
         ...         def __init__(
-        ...             self, service: DataService, port: int, host: str, **kwargs: Any
+        ...             self,
+        ...             service: DataService,
+        ...             port: int,
+        ...             host: str,
+        ...             state_manager: StateManager,
+        ...             **kwargs: Any
         ...         ):
         ...             self.service = service
+        ...             self.state_manager = state_manager
         ...             self.port = port
         ...             self.host = host
         ...             # handle any additional arguments...
@@ -162,6 +172,7 @@ class Server:
         web_port: int = 8001,
         enable_rpc: bool = True,
         enable_web: bool = True,
+        filename: Optional[str | Path] = None,
         use_forking_server: bool = False,
         web_settings: dict[str, Any] = {},
         additional_servers: list[AdditionalServer] = [],
@@ -180,7 +191,7 @@ class Server:
         self._additional_servers = additional_servers
         self.should_exit = False
         self.servers: dict[str, asyncio.Future[Any]] = {}
-        self.executor: Union[ThreadPoolExecutor, None] = None
+        self.executor: ThreadPoolExecutor | None = None
         self._info: dict[str, Any] = {
             "name": self._service.get_service_name(),
             "version": __version__,
@@ -192,6 +203,10 @@ class Server:
             "additional_servers": [],
             **kwargs,
         }
+        self._state_manager = StateManager(self._service, filename)
+        if getattr(self._service, "_filename", None) is not None:
+            self._service._state_manager = self._state_manager
+        self._state_manager.load_state()
 
     def run(self) -> None:
         """
@@ -254,16 +269,10 @@ class Server:
                 self._service,
                 port=server["port"],
                 host=self._host,
+                state_manager=self._state_manager,
                 info=self._info,
                 **server["kwargs"],
             )
-            try:
-                addin_server.install_signal_handlers = lambda: None  # type: ignore
-            except Exception:
-                logger.debug(
-                    "Additional server does not have a method called "
-                    "'install_signal_handlers'."
-                )
 
             server_name = (
                 addin_server.__module__ + "." + addin_server.__class__.__name__
@@ -283,6 +292,7 @@ class Server:
             self._wapi: WebAPI = WebAPI(
                 service=self._service,
                 info=self._info,
+                state_manager=self._state_manager,
                 **self._kwargs,
             )
             web_server = uvicorn.Server(
@@ -334,9 +344,9 @@ class Server:
     async def shutdown(self) -> None:
         logger.info("Shutting down")
 
-        logger.info(f"Saving data to {self._service._filename}.")
-        if self._service._filename is not None:
-            self._service.write_to_file()
+        logger.info(f"Saving data to {self._state_manager.filename}.")
+        if self._state_manager is not None:
+            self._state_manager.save_state()
 
         await self.__cancel_servers()
         await self.__cancel_tasks()
@@ -370,20 +380,16 @@ class Server:
             # Signals can only be listened to from the main thread.
             return
 
-        try:
-            for sig in HANDLED_SIGNALS:
-                self._loop.add_signal_handler(sig, self.handle_exit, sig, None)
-        except NotImplementedError:
-            # Windows
-            for sig in HANDLED_SIGNALS:
-                signal.signal(sig, self.handle_exit)
+        for sig in HANDLED_SIGNALS:
+            signal.signal(sig, self.handle_exit)
 
     def handle_exit(self, sig: int = 0, frame: Optional[FrameType] = None) -> None:
-        logger.info("Handling exit")
         if self.should_exit and sig == signal.SIGINT:
-            self.force_exit = True
+            logger.warning(f"Received signal {sig}, forcing exit...")
+            os._exit(1)
         else:
             self.should_exit = True
+            logger.warning(f"Received signal {sig}, exiting... (CTRL+C to force quit)")
 
     def custom_exception_handler(
         self, loop: asyncio.AbstractEventLoop, context: dict[str, Any]

src/pydase/server/web_server.py

@@ -1,15 +1,21 @@
+import logging
 from pathlib import Path
-from typing import Any, TypedDict, Union
+from typing import Any, TypedDict
 
-import socketio
+import socketio  # type: ignore
 from fastapi import FastAPI
 from fastapi.middleware.cors import CORSMiddleware
+from fastapi.responses import FileResponse
 from fastapi.staticfiles import StaticFiles
-from loguru import logger
 
 from pydase import DataService
+from pydase.data_service.data_service import process_callable_attribute
+from pydase.data_service.state_manager import StateManager
+from pydase.utils.helpers import get_object_attr_from_path_list
 from pydase.version import __version__
 
+logger = logging.getLogger(__name__)
+
 
 class UpdateDict(TypedDict):
     """
@@ -40,6 +46,25 @@ class UpdateDict(TypedDict):
     value: Any
 
 
+class RunMethodDict(TypedDict):
+    """
+    A TypedDict subclass representing a dictionary used for running methods from the
+    exposed DataService.
+
+    Attributes:
+        name (str): The name of the method to be run.
+        parent_path (str): The access path for the parent object of the method to be
+            run. This is used to construct the full access path for the method. For
+            example, for an method with access path 'attr1.list_attr[0].method_name',
+            'attr1.list_attr[0]' would be the parent_path.
+        kwargs (dict[str, Any]): The arguments passed to the method.
+    """
+
+    name: str
+    parent_path: str
+    kwargs: dict[str, Any]
+
+
 class WebAPI:
     __sio_app: socketio.ASGIApp
     __fastapi_app: FastAPI
@@ -47,14 +72,16 @@ class WebAPI:
     def __init__(  # noqa: CFQ002
         self,
         service: DataService,
-        frontend: Union[str, Path, None] = None,
-        css: Union[str, Path, None] = None,
+        state_manager: StateManager,
+        frontend: str | Path | None = None,
+        css: str | Path | None = None,
         enable_CORS: bool = True,
         info: dict[str, Any] = {},
         *args: Any,
         **kwargs: Any,
     ):
         self.service = service
+        self.state_manager = state_manager
         self.frontend = frontend
         self.css = css
         self.enable_CORS = enable_CORS
@@ -73,18 +100,27 @@ class WebAPI:
             sio = socketio.AsyncServer(async_mode="asgi")
 
         @sio.event  # type: ignore
-        def frontend_update(sid: str, data: UpdateDict) -> Any:
+        def set_attribute(sid: str, data: UpdateDict) -> Any:
             logger.debug(f"Received frontend update: {data}")
-            path_list, attr_name = data["parent_path"].split("."), data["name"]
+            path_list = [*data["parent_path"].split("."), data["name"]]
             path_list.remove("DataService")  # always at the start, does not do anything
-            return self.service.update_DataService_attribute(
-                path_list=path_list, attr_name=attr_name, value=data["value"]
+            path = ".".join(path_list)
+            return self.state_manager.set_service_attribute_value_by_path(
+                path=path, value=data["value"]
             )
 
+        @sio.event  # type: ignore
+        def run_method(sid: str, data: RunMethodDict) -> Any:
+            logger.debug(f"Running method: {data}")
+            path_list = [*data["parent_path"].split("."), data["name"]]
+            path_list.remove("DataService")  # always at the start, does not do anything
+            method = get_object_attr_from_path_list(self.service, path_list)
+            return process_callable_attribute(method, data["kwargs"])
+
         self.__sio = sio
         self.__sio_app = socketio.ASGIApp(self.__sio)
 
-    def setup_fastapi_app(self) -> None:  # noqa: CFQ004
+    def setup_fastapi_app(self) -> None:  # noqa
         app = FastAPI()
 
         if self.enable_CORS:
@@ -97,7 +133,6 @@ class WebAPI:
             )
         app.mount("/ws", self.__sio_app)
 
-        # @app.get("/version", include_in_schema=False)
         @app.get("/version")
         def version() -> str:
             return __version__
@@ -112,7 +147,14 @@ class WebAPI:
 
         @app.get("/service-properties")
         def service_properties() -> dict[str, Any]:
-            return self.service.serialize()
+            return self.state_manager.cache
+
+        # exposing custom.css file provided by user
+        if self.css is not None:
+
+            @app.get("/custom.css")
+            async def styles() -> FileResponse:
+                return FileResponse(str(self.css))
 
         app.mount(
             "/",
@@ -124,14 +166,6 @@ class WebAPI:
 
         self.__fastapi_app = app
 
-    def add_endpoint(self, name: str) -> None:
-        # your endpoint creation code
-        pass
-
-    def get_custom_openapi(self) -> None:
-        # your custom openapi generation code
-        pass
-
     @property
     def sio(self) -> socketio.AsyncServer:
         return self.__sio

src/pydase/units.py

@@ -1,19 +1,21 @@
-from typing import TypedDict, Union
+from typing import TypedDict
 
 import pint
-from pint import Quantity
 
-units = pint.UnitRegistry()
+units: pint.UnitRegistry = pint.UnitRegistry(autoconvert_offset_to_baseunit=True)
 units.default_format = "~P"  # pretty and short format
 
+Quantity = pint.Quantity
+Unit = units.Unit
+
 
 class QuantityDict(TypedDict):
-    magnitude: Union[int, float]
+    magnitude: int | float
     unit: str
 
 
 def convert_to_quantity(
-    value: Union[QuantityDict, float, int, Quantity], unit: str = ""
+    value: QuantityDict | float | int | Quantity, unit: str = ""
 ) -> Quantity:
     """
     Convert a given value into a pint.Quantity object with the specified unit.
@@ -45,10 +47,10 @@ def convert_to_quantity(
           will be unitless.
     """
 
-    if isinstance(value, (int, float)):
-        quantity = float(value) * units(unit)
+    if isinstance(value, int | float):
+        quantity = float(value) * Unit(unit)
     elif isinstance(value, dict):
-        quantity = float(value["magnitude"]) * units(value["unit"])
+        quantity = float(value["magnitude"]) * Unit(value["unit"])
     else:
         quantity = value
     return quantity  # type: ignore

src/pydase/utils/helpers.py

@@ -1,13 +1,22 @@
-import re
+import inspect
+import logging
 from itertools import chain
-from typing import Any, Optional, Union, cast
+from typing import Any, Optional
 
-from loguru import logger
-
-STANDARD_TYPES = ("int", "float", "bool", "str", "Enum", "NoneType", "Quantity")
+logger = logging.getLogger(__name__)
 
 
-def get_class_and_instance_attributes(obj: Any) -> dict[str, Any]:
+def get_attribute_doc(attr: Any) -> Optional[str]:
+    """This function takes an input attribute attr and returns its documentation
+    string if it's different from the documentation of its type, otherwise,
+    it returns None.
+    """
+    attr_doc = inspect.getdoc(attr)
+    attr_class_doc = inspect.getdoc(type(attr))
+    return attr_doc if attr_class_doc != attr_doc else None
+
+
+def get_class_and_instance_attributes(obj: object) -> dict[str, Any]:
     """Dictionary containing all attributes (both instance and class level) of a
     given object.
 
@@ -22,7 +31,7 @@ def get_class_and_instance_attributes(obj: Any) -> dict[str, Any]:
     return attrs
 
 
-def get_object_attr_from_path(target_obj: Any, path: list[str]) -> Any:
+def get_object_attr_from_path_list(target_obj: Any, path: list[str]) -> Any:
     """
     Traverse the object tree according to the given path.
 
@@ -55,218 +64,9 @@ def get_object_attr_from_path(target_obj: Any, path: list[str]) -> Any:
     return target_obj
 
 
-def generate_paths_from_DataService_dict(
-    data: dict, parent_path: str = ""
-) -> list[str]:
-    """
-    Recursively generate paths from a dictionary representing a DataService object.
-
-    This function traverses through a nested dictionary, which is typically obtained
-    from serializing a DataService object. The function generates a list where each
-    element is a string representing the path to each terminal value in the original
-    dictionary.
-
-    The paths are represented as strings, with dots ('.') denoting nesting levels and
-    square brackets ('[]') denoting list indices.
-
-    Args:
-        data (dict): The input dictionary to generate paths from. This is typically
-        obtained from serializing a DataService object.
-        parent_path (str, optional): The current path up to the current level of
-        recursion. Defaults to ''.
-
-    Returns:
-        list[str]: A list with paths as elements.
-
-    Note:
-        The function ignores keys whose "type" is "method", as these represent methods
-        of the DataService object and not its state.
-
-    Example:
-    -------
-
-    >>> {
-    ...     "attr1": {"type": "int", "value": 10},
-    ...     "attr2": {
-    ...         "type": "list",
-    ...         "value": [{"type": "int", "value": 1}, {"type": "int", "value": 2}],
-    ...     },
-    ...     "add": {
-    ...         "type": "method",
-    ...         "async": False,
-    ...         "parameters": {"a": "float", "b": "int"},
-    ...         "doc": "Returns the sum of the numbers a and b.",
-    ...     },
-    ... }
-    >>> print(generate_paths_from_DataService_dict(nested_dict))
-    [attr1, attr2[0], attr2[1]]
-    """
-
-    paths = []
-    for key, value in data.items():
-        if value["type"] == "method":
-            # ignoring methods
-            continue
-        new_path = f"{parent_path}.{key}" if parent_path else key
-        if isinstance(value["value"], dict) and value["type"] != "Quantity":
-            paths.extend(generate_paths_from_DataService_dict(value["value"], new_path))  # type: ignore
-        elif isinstance(value["value"], list):
-            for index, item in enumerate(value["value"]):
-                indexed_key_path = f"{new_path}[{index}]"
-                if isinstance(item["value"], dict):
-                    paths.extend(  # type: ignore
-                        generate_paths_from_DataService_dict(
-                            item["value"], indexed_key_path
-                        )
-                    )
-                else:
-                    paths.append(indexed_key_path)  # type: ignore
-        else:
-            paths.append(new_path)  # type: ignore
-    return paths
-
-
-def extract_dict_or_list_entry(
-    data: dict[str, Any], key: str
-) -> Union[dict[str, Any], None]:
-    """
-    Extract a nested dictionary or list entry based on the provided key.
-
-    Given a dictionary and a key, this function retrieves the corresponding nested
-    dictionary or list entry. If the key includes an index in the format "[<index>]",
-    the function assumes that the corresponding entry in the dictionary is a list, and
-    it will attempt to retrieve the indexed item from that list.
-
-    Args:
-        data (dict): The input dictionary containing nested dictionaries or lists.
-        key (str): The key specifying the desired entry within the dictionary. The key
-            can be a regular dictionary key or can include an index in the format
-            "[<index>]" to retrieve an item from a nested list.
-
-    Returns:
-        dict | None: The nested dictionary or list item found for the given key. If the
-            key is invalid, or if the specified index is out of bounds for a list, it
-            returns None.
-
-    Example:
-        >>> data = {
-        ...     "attr1": [
-        ...         {"type": "int", "value": 10}, {"type": "string", "value": "hello"}
-        ...     ],
-        ...     "attr2": {
-        ...         "type": "MyClass",
-        ...         "value": {"sub_attr": {"type": "float", "value": 20.5}}
-        ...     }
-        ... }
-
-        >>> extract_dict_or_list_entry(data, "attr1[1]")
-        {"type": "string", "value": "hello"}
-
-        >>> extract_dict_or_list_entry(data, "attr2")
-        {"type": "MyClass", "value": {"sub_attr": {"type": "float", "value": 20.5}}}
-    """
-
-    attr_name = key
-    index: Optional[int] = None
-
-    # Check if the key contains an index part like '[<index>]'
-    if "[" in key and key.endswith("]"):
-        attr_name, index_part = key.split("[", 1)
-        index_part = index_part.rstrip("]")  # remove the closing bracket
-
-        # Convert the index part to an integer
-        if index_part.isdigit():
-            index = int(index_part)
-        else:
-            logger.error(f"Invalid index format in key: {key}")
-
-    current_data: Union[dict[str, Any], list[dict[str, Any]], None] = data.get(
-        attr_name, None
-    )
-    if not isinstance(current_data, dict):
-        # key does not exist in dictionary, e.g. when class does not have this
-        # attribute
-        return None
-
-    if isinstance(current_data["value"], list):
-        current_data = current_data["value"]
-
-        if index is not None and 0 <= index < len(current_data):
-            current_data = current_data[index]
-        else:
-            return None
-
-    # When the attribute is a class instance, the attributes are nested in the
-    # "value" key
-    if current_data["type"] not in STANDARD_TYPES:
-        current_data = cast(dict[str, Any], current_data.get("value", None))  # type: ignore
-        assert isinstance(current_data, dict)
-
-    return current_data
-
-
-def get_nested_value_from_DataService_by_path_and_key(
-    data: dict[str, Any], path: str, key: str = "value"
-) -> Any:
-    """
-    Get the value associated with a specific key from a dictionary given a path.
-
-    This function traverses the dictionary according to the path provided and
-    returns the value associated with the specified key at that path. The path is
-    a string with dots connecting the levels and brackets indicating list indices.
-
-    The function can handle complex dictionaries where data is nested within different
-    types of objects. It checks the type of each object it encounters and correctly
-    descends into the object if it is not a standard type (i.e., int, float, bool, str,
-    Enum).
-
-    Args:
-        data (dict): The input dictionary to get the value from.
-        path (str): The path to the value in the dictionary.
-        key (str, optional): The key associated with the value to be returned.
-                             Default is "value".
-
-    Returns:
-        Any: The value associated with the specified key at the given path in the
-        dictionary.
-
-    Examples:
-        Let's consider the following dictionary:
-
-        >>> data = {
-        >>>     "attr1": {"type": "int", "value": 10},
-        >>>     "attr2": {
-                    "type": "MyClass",
-                    "value": {"attr3": {"type": "float", "value": 20.5}}
-                }
-        >>> }
-
-        The function can be used to get the value of 'attr1' as follows:
-        >>> get_nested_value_by_path_and_key(data, "attr1")
-        10
-
-        It can also be used to get the value of 'attr3', which is nested within 'attr2',
-        as follows:
-        >>> get_nested_value_by_path_and_key(data, "attr2.attr3", "type")
-        float
-    """
-
-    # Split the path into parts
-    parts: list[str] = re.split(r"\.", path)  # Split by '.'
-    current_data: Union[dict[str, Any], None] = data
-
-    for part in parts:
-        if current_data is None:
-            return
-        current_data = extract_dict_or_list_entry(current_data, part)
-
-    if isinstance(current_data, dict):
-        return current_data.get(key, None)
-
-
 def convert_arguments_to_hinted_types(
     args: dict[str, Any], type_hints: dict[str, Any]
-) -> Union[dict[str, Any], str]:
+) -> dict[str, Any] | str:
     """
     Convert the given arguments to their types hinted in the type_hints dictionary.
 
@@ -308,7 +108,7 @@ def convert_arguments_to_hinted_types(
 
 
 def update_value_if_changed(
-    target: Any, attr_name_or_index: Union[str, int], new_value: Any
+    target: Any, attr_name_or_index: str | int, new_value: Any
 ) -> None:
     """
     Updates the value of an attribute or a list element on a target object if the new
@@ -348,38 +148,34 @@ def parse_list_attr_and_index(attr_string: str) -> tuple[str, Optional[int]]:
     """
     Parses an attribute string and extracts a potential list attribute name and its
     index.
+    Logs an error if the index is not a valid digit.
 
-    This function examines the provided attribute string. If the string contains square
-    brackets, it assumes that it's a list attribute and the string within brackets is
-    the index of an element. It then returns the attribute name and the index as an
-    integer. If no brackets are present, the function assumes it's a regular attribute
-    and returns the attribute name and None as the index.
-
-    Parameters:
-    -----------
-    attr_string: str
-        The attribute string to parse. Can be a regular attribute name (e.g.
-        'attr_name') or a list attribute with an index (e.g. 'list_attr[2]').
+    Args:
+        attr_string (str):
+            The attribute string to parse. Can be a regular attribute name (e.g.,
+            'attr_name') or a list attribute with an index (e.g., 'list_attr[2]').
 
     Returns:
-    --------
-    tuple: (str, Optional[int])
-        A tuple containing the attribute name as a string and the index as an integer if
-        present, otherwise None.
+        tuple[str, Optional[int]]:
+            A tuple containing the attribute name as a string and the index as an
+            integer if present, otherwise None.
 
-    Example:
-    --------
-    >>> parse_list_attr_and_index('list_attr[2]')
-    ('list_attr', 2)
-    >>> parse_list_attr_and_index('attr_name')
-    ('attr_name', None)
+    Examples:
+        >>> parse_attribute_and_index('list_attr[2]')
+        ('list_attr', 2)
+        >>> parse_attribute_and_index('attr_name')
+        ('attr_name', None)
     """
 
-    attr_name = attr_string
     index = None
-    if "[" in attr_string and "]" in attr_string:
-        attr_name, idx = attr_string[:-1].split("[")
-        index = int(idx)
+    attr_name = attr_string
+    if "[" in attr_string and attr_string.endswith("]"):
+        attr_name, index_part = attr_string.split("[", 1)
+        index_part = index_part.rstrip("]")
+        if index_part.isdigit():
+            index = int(index_part)
+        else:
+            logger.error(f"Invalid index format in key: {attr_name}")
     return attr_name, index
 
 

src/pydase/utils/logging.py

@@ -1,82 +1,115 @@
 import logging
 import sys
-from types import FrameType
-from typing import Optional, Union
+from copy import copy
+from typing import Optional
 
-import loguru
-import rpyc
+import uvicorn.logging
 from uvicorn.config import LOGGING_CONFIG
 
 import pydase.config
 
-ALLOWED_LOG_LEVELS = ["DEBUG", "INFO", "ERROR"]
+
+class DefaultFormatter(uvicorn.logging.ColourizedFormatter):
+    """
+    A custom log formatter class that:
+
+    * Outputs the LOG_LEVEL with an appropriate color.
+    * If a log call includes an `extras={"color_message": ...}` it will be used
+      for formatting the output, instead of the plain text message.
+    """
+
+    def formatMessage(self, record: logging.LogRecord) -> str:
+        recordcopy = copy(record)
+        levelname = recordcopy.levelname
+        seperator = " " * (8 - len(recordcopy.levelname))
+        if self.use_colors:
+            levelname = self.color_level_name(levelname, recordcopy.levelno)
+            if "color_message" in recordcopy.__dict__:
+                recordcopy.msg = recordcopy.__dict__["color_message"]
+                recordcopy.__dict__["message"] = recordcopy.getMessage()
+        recordcopy.__dict__["levelprefix"] = levelname + seperator
+        return logging.Formatter.formatMessage(self, recordcopy)
+
+    def should_use_colors(self) -> bool:
+        return sys.stderr.isatty()  # pragma: no cover
 
 
-# from: https://github.com/Delgan/loguru section
-# "Entirely compatible with standard logging"
-class InterceptHandler(logging.Handler):
-    def emit(self, record: logging.LogRecord) -> None:
-        # Ignore "asyncio.CancelledError" raised by uvicorn
-        if record.name == "uvicorn.error" and "CancelledError" in record.msg:
-            return
+def setup_logging(level: Optional[str | int] = None) -> None:
+    """
+    Configures the logging settings for the application.
 
-        # Get corresponding Loguru level if it exists.
-        level: Union[int, str]
-        try:
-            level = loguru.logger.level(record.levelname).name
-        except ValueError:
-            level = record.levelno
+    This function sets up logging with specific formatting and colorization of log
+    messages. The log level is determined based on the application's operation mode,
+    with an option to override the level. By default, in a development environment, the
+    log level is set to DEBUG, whereas in other environments, it is set to INFO.
 
-        # Find caller from where originated the logged message.
-        frame: Optional[FrameType] = sys._getframe(6)
-        depth = 6
-        while frame and frame.f_code.co_filename == logging.__file__:
-            frame = frame.f_back
-            depth += 1
+    Parameters:
+        level (Optional[str | int]):
+            A specific log level to set for the application. If None, the log level is
+            determined based on the application's operation mode. Accepts standard log
+            level names ('DEBUG', 'INFO', etc.) and corresponding numerical values.
 
-        try:
-            msg = record.getMessage()
-        except TypeError:
-            # A `TypeError` is raised when the `msg` string expects more arguments
-            # than are provided by `args`. This can happen when intercepting log
-            # messages with a certain format, like
-            # >    logger.debug("call: %s%r", method_name, *args)  # in tiqi_rpc
-            # where `*args` unpacks a sequence of values that should replace
-            # placeholders in the string.
-            msg = record.msg % (record.args[0], record.args[2:])  # type: ignore
+    Example:
 
-        loguru.logger.opt(depth=depth, exception=record.exc_info).log(level, msg)
+    ```python
+    >>> import logging
+    >>> setup_logging(logging.DEBUG)
+    >>> setup_logging("INFO")
+    ```
+    """
 
-
-def setup_logging(level: Optional[str] = None) -> None:
-    loguru.logger.debug("Configuring service logging.")
+    logger = logging.getLogger()
 
     if pydase.config.OperationMode().environment == "development":
-        log_level = "DEBUG"
+        log_level = logging.DEBUG
     else:
-        log_level = "INFO"
+        log_level = logging.INFO
 
-    if level is not None and level in ALLOWED_LOG_LEVELS:
-        log_level = level
+    # If a level is specified, check whether it's a string or an integer.
+    if level is not None:
+        if isinstance(level, str):
+            # Convert known log level strings directly to their corresponding logging
+            # module constants.
+            level_name = level.upper()  # Ensure level names are uppercase
+            if hasattr(logging, level_name):
+                log_level = getattr(logging, level_name)
+            else:
+                raise ValueError(
+                    f"Invalid log level: {level}. Must be one of 'DEBUG', 'INFO', "
+                    "'WARNING', 'ERROR', etc."
+                )
+        elif isinstance(level, int):
+            log_level = level  # Directly use integer levels
+        else:
+            raise ValueError("Log level must be a string or an integer.")
 
-    loguru.logger.remove()
-    loguru.logger.add(sys.stderr, level=log_level)
+    # Set the logger's level.
+    logger.setLevel(log_level)
 
-    # set up the rpyc logger *before* adding the InterceptHandler to the logging module
-    rpyc.setup_logger(quiet=True)  # type: ignore
+    # create console handler and set level to debug
+    ch = logging.StreamHandler()
 
-    logging.basicConfig(handlers=[InterceptHandler()], level=0)
+    # add formatter to ch
+    ch.setFormatter(
+        DefaultFormatter(
+            fmt="%(asctime)s.%(msecs)03d | %(levelprefix)s | %(name)s:%(funcName)s:%(lineno)d - %(message)s",
+            datefmt="%Y-%m-%d %H:%M:%S",
+        )
+    )
+
+    # add ch to logger
+    logger.addHandler(ch)
+
+    logger.debug("Configuring service logging.")
     logging.getLogger("asyncio").setLevel(logging.INFO)
     logging.getLogger("urllib3").setLevel(logging.INFO)
 
-    # overwriting the uvicorn logging config to use the loguru intercept handler
-    LOGGING_CONFIG["handlers"] = {
-        "default": {
-            "()": InterceptHandler,
-            "formatter": "default",
-        },
-        "access": {
-            "()": InterceptHandler,
-            "formatter": "access",
-        },
-    }
+    # configuring uvicorn logger
+    LOGGING_CONFIG["formatters"]["default"][
+        "fmt"
+    ] = "%(asctime)s.%(msecs)03d | %(levelprefix)s %(message)s"
+    LOGGING_CONFIG["formatters"]["default"]["datefmt"] = "%Y-%m-%d %H:%M:%S"
+    LOGGING_CONFIG["formatters"]["access"][
+        "fmt"
+    ] = '%(asctime)s.%(msecs)03d | %(levelprefix)s %(client_addr)s - "%(request_line)s" %(status_code)s'
+    LOGGING_CONFIG["formatters"]["access"]["datefmt"] = "%Y-%m-%d %H:%M:%S"

src/pydase/utils/serializer.py

@@ -0,0 +1,387 @@
+import inspect
+import logging
+from collections.abc import Callable
+from enum import Enum
+from typing import Any, Optional
+
+import pydase.units as u
+from pydase.data_service.abstract_data_service import AbstractDataService
+from pydase.utils.helpers import (
+    get_attribute_doc,
+    get_component_class_names,
+    parse_list_attr_and_index,
+)
+
+logger = logging.getLogger(__name__)
+
+
+class SerializationPathError(Exception):
+    pass
+
+
+class SerializationValueError(Exception):
+    pass
+
+
+class Serializer:
+    @staticmethod
+    def serialize_object(obj: Any) -> dict[str, Any]:
+        result: dict[str, Any] = {}
+        if isinstance(obj, AbstractDataService):
+            result = Serializer._serialize_DataService(obj)
+
+        elif isinstance(obj, list):
+            result = Serializer._serialize_list(obj)
+
+        elif isinstance(obj, dict):
+            result = Serializer._serialize_dict(obj)
+
+        # Special handling for u.Quantity
+        elif isinstance(obj, u.Quantity):
+            result = Serializer._serialize_Quantity(obj)
+
+        # Handling for Enums
+        elif isinstance(obj, Enum):
+            result = Serializer._serialize_enum(obj)
+
+        # Methods and coroutines
+        elif inspect.isfunction(obj) or inspect.ismethod(obj):
+            result = Serializer._serialize_method(obj)
+
+        else:
+            obj_type = type(obj).__name__
+            value = obj
+            readonly = False
+            doc = get_attribute_doc(obj)
+            result = {
+                "type": obj_type,
+                "value": value,
+                "readonly": readonly,
+                "doc": doc,
+            }
+
+        return result
+
+    @staticmethod
+    def _serialize_enum(obj: Enum) -> dict[str, Any]:
+        value = obj.name
+        readonly = False
+        doc = get_attribute_doc(obj)
+        if type(obj).__base__.__name__ == "ColouredEnum":
+            obj_type = "ColouredEnum"
+        else:
+            obj_type = "Enum"
+
+        return {
+            "type": obj_type,
+            "value": value,
+            "readonly": readonly,
+            "doc": doc,
+            "enum": {
+                name: member.value for name, member in obj.__class__.__members__.items()
+            },
+        }
+
+    @staticmethod
+    def _serialize_Quantity(obj: u.Quantity) -> dict[str, Any]:
+        obj_type = "Quantity"
+        readonly = False
+        doc = get_attribute_doc(obj)
+        value = {"magnitude": obj.m, "unit": str(obj.u)}
+        return {
+            "type": obj_type,
+            "value": value,
+            "readonly": readonly,
+            "doc": doc,
+        }
+
+    @staticmethod
+    def _serialize_dict(obj: dict[str, Any]) -> dict[str, Any]:
+        obj_type = "dict"
+        readonly = False
+        doc = get_attribute_doc(obj)
+        value = {key: Serializer.serialize_object(val) for key, val in obj.items()}
+        return {
+            "type": obj_type,
+            "value": value,
+            "readonly": readonly,
+            "doc": doc,
+        }
+
+    @staticmethod
+    def _serialize_list(obj: list[Any]) -> dict[str, Any]:
+        obj_type = "list"
+        readonly = False
+        doc = get_attribute_doc(obj)
+        value = [Serializer.serialize_object(o) for o in obj]
+        return {
+            "type": obj_type,
+            "value": value,
+            "readonly": readonly,
+            "doc": doc,
+        }
+
+    @staticmethod
+    def _serialize_method(obj: Callable[..., Any]) -> dict[str, Any]:
+        obj_type = "method"
+        value = None
+        readonly = True
+        doc = get_attribute_doc(obj)
+
+        # Store parameters and their anotations in a dictionary
+        sig = inspect.signature(obj)
+        parameters: dict[str, Optional[str]] = {}
+
+        for k, v in sig.parameters.items():
+            annotation = v.annotation
+            if annotation is not inspect._empty:
+                if isinstance(annotation, type):
+                    # Handle regular types
+                    parameters[k] = annotation.__name__
+                else:
+                    # Union, string annotation, Literal types, ...
+                    parameters[k] = str(annotation)
+            else:
+                parameters[k] = None
+
+        return {
+            "type": obj_type,
+            "value": value,
+            "readonly": readonly,
+            "doc": doc,
+            "async": inspect.iscoroutinefunction(obj),
+            "parameters": parameters,
+        }
+
+    @staticmethod
+    def _serialize_DataService(obj: AbstractDataService) -> dict[str, Any]:
+        readonly = False
+        doc = get_attribute_doc(obj)
+        obj_type = type(obj).__name__
+        if type(obj).__name__ not in get_component_class_names():
+            obj_type = "DataService"
+
+        # Get the dictionary of the base class
+        base_set = set(type(obj).__base__.__dict__)
+        # Get the dictionary of the derived class
+        derived_set = set(type(obj).__dict__)
+        # Get the difference between the two dictionaries
+        derived_only_set = derived_set - base_set
+
+        instance_dict = set(obj.__dict__)
+        # Merge the class and instance dictionaries
+        merged_set = derived_only_set | instance_dict
+        value = {}
+
+        # Iterate over attributes, properties, class attributes, and methods
+        for key in sorted(merged_set):
+            if key.startswith("_"):
+                continue  # Skip attributes that start with underscore
+
+            # Skip keys that start with "start_" or "stop_" and end with an async
+            # method name
+            if (key.startswith("start_") or key.startswith("stop_")) and key.split(
+                "_", 1
+            )[1] in {
+                name
+                for name, _ in inspect.getmembers(
+                    obj, predicate=inspect.iscoroutinefunction
+                )
+            }:
+                continue
+
+            val = getattr(obj, key)
+
+            value[key] = Serializer.serialize_object(val)
+
+            # If there's a running task for this method
+            if key in obj._task_manager.tasks:
+                task_info = obj._task_manager.tasks[key]
+                value[key]["value"] = task_info["kwargs"]
+
+            # If the DataService attribute is a property
+            if isinstance(getattr(obj.__class__, key, None), property):
+                prop: property = getattr(obj.__class__, key)
+                value[key]["readonly"] = prop.fset is None
+                value[key]["doc"] = get_attribute_doc(prop)  # overwrite the doc
+
+        return {
+            "type": obj_type,
+            "value": value,
+            "readonly": readonly,
+            "doc": doc,
+        }
+
+
+def dump(obj: Any) -> dict[str, Any]:
+    return Serializer.serialize_object(obj)
+
+
+def set_nested_value_by_path(
+    serialization_dict: dict[str, Any], path: str, value: Any
+) -> None:
+    """
+    Set a value in a nested dictionary structure, which conforms to the serialization
+    format used by `pydase.utils.serializer.Serializer`, using a dot-notation path.
+
+    Args:
+        serialization_dict:
+            The base dictionary representing data serialized with
+            `pydase.utils.serializer.Serializer`.
+        path:
+            The dot-notation path (e.g., 'attr1.attr2[0].attr3') indicating where to
+            set the value.
+        value:
+            The new value to set at the specified path.
+
+    Note:
+        - If the index equals the length of the list, the function will append the
+          serialized representation of the 'value' to the list.
+    """
+
+    parent_path_parts, attr_name = path.split(".")[:-1], path.split(".")[-1]
+    current_dict: dict[str, Any] = serialization_dict
+
+    try:
+        for path_part in parent_path_parts:
+            current_dict = get_next_level_dict_by_key(
+                current_dict, path_part, allow_append=False
+            )
+            current_dict = current_dict["value"]
+
+        current_dict = get_next_level_dict_by_key(
+            current_dict, attr_name, allow_append=True
+        )
+    except (SerializationPathError, SerializationValueError, KeyError) as e:
+        logger.error(e)
+        return
+
+    # setting the new value
+    serialized_value = dump(value)
+    if "readonly" in current_dict:
+        current_dict["value"] = serialized_value["value"]
+        current_dict["type"] = serialized_value["type"]
+    else:
+        current_dict.update(serialized_value)
+
+
+def get_nested_dict_by_path(
+    serialization_dict: dict[str, Any],
+    path: str,
+) -> dict[str, Any]:
+    parent_path_parts, attr_name = path.split(".")[:-1], path.split(".")[-1]
+    current_dict: dict[str, Any] = serialization_dict
+
+    try:
+        for path_part in parent_path_parts:
+            current_dict = get_next_level_dict_by_key(
+                current_dict, path_part, allow_append=False
+            )
+            current_dict = current_dict["value"]
+        current_dict = get_next_level_dict_by_key(
+            current_dict, attr_name, allow_append=False
+        )
+
+    except (SerializationPathError, SerializationValueError, KeyError) as e:
+        logger.error(e)
+        return {}
+
+    return current_dict
+
+
+def get_next_level_dict_by_key(
+    serialization_dict: dict[str, Any],
+    attr_name: str,
+    allow_append: bool = False,
+) -> dict[str, Any]:
+    """
+    Retrieve a nested dictionary entry or list item from a data structure serialized
+    with `pydase.utils.serializer.Serializer`.
+
+    Args:
+        serialization_dict: The base dictionary representing serialized data.
+        attr_name: The key name representing the attribute in the dictionary,
+            e.g. 'list_attr[0]' or 'attr'
+        allow_append: Flag to allow appending a new entry if `index` is out of range by
+            one.
+
+    Returns:
+        The dictionary or list item corresponding to the attribute and index.
+
+    Raises:
+        SerializationPathError: If the path composed of `attr_name` and `index` is
+                                invalid or leads to an IndexError or KeyError.
+        SerializationValueError: If the expected nested structure is not a dictionary.
+    """
+    # Check if the key contains an index part like 'attr_name[<index>]'
+    attr_name, index = parse_list_attr_and_index(attr_name)
+
+    try:
+        if index is not None:
+            serialization_dict = serialization_dict[attr_name]["value"][index]
+        else:
+            serialization_dict = serialization_dict[attr_name]
+    except IndexError as e:
+        if allow_append and index == len(serialization_dict[attr_name]["value"]):
+            # Appending to list
+            serialization_dict[attr_name]["value"].append({})
+            serialization_dict = serialization_dict[attr_name]["value"][index]
+        else:
+            raise SerializationPathError(
+                f"Error occured trying to change '{attr_name}[{index}]': {e}"
+            )
+    except KeyError:
+        raise SerializationPathError(
+            f"Error occured trying to access the key '{attr_name}': it is either "
+            "not present in the current dictionary or its value does not contain "
+            "a 'value' key."
+        )
+
+    if not isinstance(serialization_dict, dict):
+        raise SerializationValueError(
+            f"Expected a dictionary at '{attr_name}', but found type "
+            f"'{type(serialization_dict).__name__}' instead."
+        )
+
+    return serialization_dict
+
+
+def generate_serialized_data_paths(
+    data: dict[str, Any], parent_path: str = ""
+) -> list[str]:
+    """
+    Generate a list of access paths for all attributes in a dictionary representing
+    data serialized with `pydase.utils.serializer.Serializer`, excluding those that are
+    methods.
+
+    Args:
+        data: The dictionary representing serialized data, typically produced by
+            `pydase.utils.serializer.Serializer`.
+        parent_path: The base path to prepend to the keys in the `data` dictionary to
+            form the access paths. Defaults to an empty string.
+
+    Returns:
+        A list of strings where each string is a dot-notation access path to an
+        attribute in the serialized data.
+    """
+
+    paths = []
+    for key, value in data.items():
+        if value["type"] == "method":
+            # ignoring methods
+            continue
+        new_path = f"{parent_path}.{key}" if parent_path else key
+        if isinstance(value["value"], dict) and value["type"] != "Quantity":
+            paths.extend(generate_serialized_data_paths(value["value"], new_path))  # type: ignore
+        elif isinstance(value["value"], list):
+            for index, item in enumerate(value["value"]):
+                indexed_key_path = f"{new_path}[{index}]"
+                if isinstance(item["value"], dict):
+                    paths.extend(  # type: ignore
+                        generate_serialized_data_paths(item["value"], indexed_key_path)
+                    )
+                else:
+                    paths.append(indexed_key_path)  # type: ignore
+        else:
+            paths.append(new_path)  # type: ignore
+    return paths

src/pydase/utils/warnings.py

@@ -1,4 +1,8 @@
-from loguru import logger
+import logging
+
+from pydase.utils.helpers import get_component_class_names
+
+logger = logging.getLogger(__name__)
 
 
 def warn_if_instance_class_does_not_inherit_from_DataService(__value: object) -> None:
@@ -13,7 +17,8 @@ def warn_if_instance_class_does_not_inherit_from_DataService(__value: object) ->
             "asyncio.unix_events",
             "_abc",
         ]
-        and base_class_name not in ["DataService", "list", "Enum"]
+        and base_class_name
+        not in ["DataService", "list", "Enum"] + get_component_class_names()
         and type(__value).__name__ not in ["CallbackManager", "TaskManager", "Quantity"]
     ):
         logger.warning(

tests/__init__.py

@@ -1,26 +0,0 @@
-from collections.abc import Generator
-from typing import Any
-
-import pytest
-from loguru import logger
-from pytest import LogCaptureFixture
-
-from pydase import DataService
-from pydase.data_service.callback_manager import CallbackManager
-
-
-@pytest.fixture
-def caplog(caplog: LogCaptureFixture) -> Generator[LogCaptureFixture, Any, None]:
-    handler_id = logger.add(caplog.handler, format="{message}")
-    yield caplog
-    logger.remove(handler_id)
-
-
-def emit(self: Any, parent_path: str, name: str, value: Any) -> None:
-    if isinstance(value, DataService):
-        value = value.serialize()
-
-    print(f"{parent_path}.{name} = {value}")
-
-
-CallbackManager.emit_notification = emit  # type: ignore

tests/components/test_coloured_enum.py

@@ -0,0 +1,41 @@
+from pytest import LogCaptureFixture
+
+from pydase.components.coloured_enum import ColouredEnum
+from pydase.data_service.data_service import DataService
+
+
+def test_ColouredEnum(caplog: LogCaptureFixture) -> None:
+    class MyStatus(ColouredEnum):
+        RUNNING = "#00FF00"
+        FAILING = "#FF0000"
+
+    class ServiceClass(DataService):
+        _status = MyStatus.RUNNING
+
+        @property
+        def status(self) -> MyStatus:
+            return self._status
+
+        @status.setter
+        def status(self, value: MyStatus) -> None:
+            # do something ...
+            self._status = value
+
+    service = ServiceClass()
+
+    service.status = MyStatus.FAILING
+
+    assert "ServiceClass.status changed to MyStatus.FAILING" in caplog.text
+
+
+def test_warning(caplog: LogCaptureFixture) -> None:  # noqa
+    class MyStatus(ColouredEnum):
+        RUNNING = "#00FF00"
+        FAILING = "#FF0000"
+
+    class ServiceClass(DataService):
+        status = MyStatus.RUNNING
+
+    assert (
+        "Warning: Class MyStatus does not inherit from DataService." not in caplog.text
+    )

tests/components/test_number_slider.py

@@ -3,10 +3,8 @@ from pytest import CaptureFixture, LogCaptureFixture
 from pydase.components.number_slider import NumberSlider
 from pydase.data_service.data_service import DataService
 
-from .. import caplog  # noqa
 
-
-def test_NumberSlider(capsys: CaptureFixture) -> None:
+def test_NumberSlider(caplog: LogCaptureFixture) -> None:
     class ServiceClass(DataService):
         number_slider = NumberSlider(1, 0, 10, 1)
         int_number_slider = NumberSlider(1, 0, 10, 1, "int")
@@ -30,28 +28,13 @@ def test_NumberSlider(capsys: CaptureFixture) -> None:
     service.number_slider.value = 10.0
     service.int_number_slider.value = 10.1
 
-    captured = capsys.readouterr()
-
-    expected_output = sorted(
-        [
-            "ServiceClass.number_slider.value = 10.0",
-            "ServiceClass.int_number_slider.value = 10",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))  # type: ignore
-    assert actual_output == expected_output
+    assert "ServiceClass.number_slider.value changed to 10.0" in caplog.text
+    assert "ServiceClass.int_number_slider.value changed to 10" in caplog.text
+    caplog.clear()
 
     service.number_slider.min = 1.1
 
-    captured = capsys.readouterr()
-
-    expected_output = sorted(
-        [
-            "ServiceClass.number_slider.min = 1.1",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))  # type: ignore
-    assert actual_output == expected_output
+    assert "ServiceClass.number_slider.min changed to 1.1" in caplog.text
 
 
 def test_init_error(caplog: LogCaptureFixture) -> None:  # noqa

tests/data_service/test_callback_manager.py

@@ -0,0 +1,42 @@
+import logging
+
+from pytest import LogCaptureFixture
+
+import pydase
+
+logger = logging.getLogger()
+
+
+def test_DataService_task_callback(caplog: LogCaptureFixture) -> None:
+    class MyService(pydase.DataService):
+        async def my_task(self) -> None:
+            logger.info("Triggered task.")
+
+        async def my_other_task(self) -> None:
+            logger.info("Triggered other task.")
+
+    service = MyService()
+    service.start_my_task()  # type: ignore
+    service.start_my_other_task()  # type: ignore
+
+    assert "MyService.my_task changed to {}" in caplog.text
+    assert "MyService.my_other_task changed to {}" in caplog.text
+
+
+def test_DataServiceList_task_callback(caplog: LogCaptureFixture) -> None:
+    class MySubService(pydase.DataService):
+        async def my_task(self) -> None:
+            logger.info("Triggered task.")
+
+        async def my_other_task(self) -> None:
+            logger.info("Triggered other task.")
+
+    class MyService(pydase.DataService):
+        sub_services_list = [MySubService() for i in range(2)]
+
+    service = MyService()
+    service.sub_services_list[0].start_my_task()  # type: ignore
+    service.sub_services_list[1].start_my_other_task()  # type: ignore
+
+    assert "MyService.sub_services_list[0].my_task changed to {}" in caplog.text
+    assert "MyService.sub_services_list[1].my_other_task changed to {}" in caplog.text

tests/data_service/test_data_service_cache.py

@@ -0,0 +1,25 @@
+import logging
+
+import pydase
+from pydase.data_service.data_service_cache import DataServiceCache
+from pydase.utils.serializer import get_nested_dict_by_path
+
+logger = logging.getLogger()
+
+
+def test_nested_attributes_cache_callback() -> None:
+    class SubClass(pydase.DataService):
+        name = "Hello"
+
+    class ServiceClass(pydase.DataService):
+        class_attr = SubClass()
+        name = "World"
+
+    test_service = ServiceClass()
+    cache = DataServiceCache(test_service)
+
+    test_service.name = "Peepz"
+    assert get_nested_dict_by_path(cache.cache, "name")["value"] == "Peepz"
+
+    test_service.class_attr.name = "Ciao"
+    assert get_nested_dict_by_path(cache.cache, "class_attr.name")["value"] == "Ciao"

tests/data_service/test_data_service_list.py

@@ -0,0 +1,129 @@
+from typing import Any
+
+from pytest import LogCaptureFixture
+
+import pydase.units as u
+from pydase import DataService
+
+
+def test_class_list_attribute(caplog: LogCaptureFixture) -> None:
+    class ServiceClass(DataService):
+        attr = [0, 1]
+
+    service_instance = ServiceClass()
+
+    service_instance.attr[0] = 1337
+    assert "ServiceClass.attr[0] changed to 1337" in caplog.text
+    caplog.clear()
+
+
+def test_instance_list_attribute(caplog: LogCaptureFixture) -> None:
+    class SubClass(DataService):
+        name = "SubClass"
+
+    class ServiceClass(DataService):
+        def __init__(self) -> None:
+            self.attr: list[Any] = [0, SubClass()]
+            super().__init__()
+
+    service_instance = ServiceClass()
+
+    service_instance.attr[0] = "Hello"
+    assert "ServiceClass.attr[0] changed to Hello" in caplog.text
+    caplog.clear()
+
+    service_instance.attr[1] = SubClass()
+    assert f"ServiceClass.attr[1] changed to {service_instance.attr[1]}" in caplog.text
+    caplog.clear()
+
+
+def test_reused_instance_list_attribute(caplog: LogCaptureFixture) -> None:
+    some_list = [0, 1, 2]
+
+    class ServiceClass(DataService):
+        def __init__(self) -> None:
+            self.attr = some_list
+            self.attr_2 = some_list
+            self.attr_3 = [0, 1, 2]
+            super().__init__()
+
+    service_instance = ServiceClass()
+
+    service_instance.attr[0] = 20
+    assert service_instance.attr == service_instance.attr_2
+    assert service_instance.attr != service_instance.attr_3
+
+    assert "ServiceClass.attr[0] changed to 20" in caplog.text
+    assert "ServiceClass.attr_2[0] changed to 20" in caplog.text
+
+
+def test_nested_reused_instance_list_attribute(caplog: LogCaptureFixture) -> None:
+    some_list = [0, 1, 2]
+
+    class SubClass(DataService):
+        attr_list = some_list
+
+        def __init__(self) -> None:
+            self.attr_list_2 = some_list
+            super().__init__()
+
+    class ServiceClass(DataService):
+        def __init__(self) -> None:
+            self.attr = some_list
+            self.subclass = SubClass()
+            super().__init__()
+
+    service_instance = ServiceClass()
+
+    service_instance.attr[0] = 20
+
+    assert service_instance.attr == service_instance.subclass.attr_list
+
+    assert "ServiceClass.attr[0] changed to 20" in caplog.text
+    assert "ServiceClass.subclass.attr_list[0] changed to 20" in caplog.text
+    assert "ServiceClass.subclass.attr_list_2[0] changed to 20" in caplog.text
+
+
+def test_protected_list_attribute(caplog: LogCaptureFixture) -> None:
+    """Changing protected lists should not emit notifications for the lists themselves,
+    but still for all properties depending on them.
+    """
+
+    class ServiceClass(DataService):
+        _attr = [0, 1]
+
+        @property
+        def list_dependend_property(self) -> int:
+            return self._attr[0]
+
+    service_instance = ServiceClass()
+
+    service_instance._attr[0] = 1337
+    assert "ServiceClass.list_dependend_property changed to 1337" in caplog.text
+
+
+def test_converting_int_to_float_entries(caplog: LogCaptureFixture) -> None:
+    class ServiceClass(DataService):
+        float_list = [0.0]
+
+    service_instance = ServiceClass()
+    service_instance.float_list[0] = 1
+
+    assert isinstance(service_instance.float_list[0], float)
+    assert "ServiceClass.float_list[0] changed to 1.0" in caplog.text
+
+
+def test_converting_number_to_quantity_entries(caplog: LogCaptureFixture) -> None:
+    class ServiceClass(DataService):
+        quantity_list: list[u.Quantity] = [1 * u.units.A]
+
+    service_instance = ServiceClass()
+    service_instance.quantity_list[0] = 4  # type: ignore
+
+    assert isinstance(service_instance.quantity_list[0], u.Quantity)
+    assert "ServiceClass.quantity_list[0] changed to 4.0 A" in caplog.text
+    caplog.clear()
+
+    service_instance.quantity_list[0] = 3.1 * u.units.mA
+    assert isinstance(service_instance.quantity_list[0], u.Quantity)
+    assert "ServiceClass.quantity_list[0] changed to 3.1 mA" in caplog.text

tests/data_service/test_state_manager.py

@@ -0,0 +1,271 @@
+import json
+from pathlib import Path
+from typing import Any
+
+from pytest import LogCaptureFixture
+
+import pydase
+import pydase.units as u
+from pydase.components.coloured_enum import ColouredEnum
+from pydase.data_service.state_manager import (
+    StateManager,
+    has_load_state_decorator,
+    load_state,
+)
+
+
+class SubService(pydase.DataService):
+    name = "SubService"
+
+
+class State(ColouredEnum):
+    RUNNING = "#0000FF80"
+    COMPLETED = "hsl(120, 100%, 50%)"
+    FAILED = "hsla(0, 100%, 50%, 0.7)"
+
+
+class Service(pydase.DataService):
+    def __init__(self, **kwargs: Any) -> None:
+        self.subservice = SubService()
+        self.some_unit: u.Quantity = 1.2 * u.units.A
+        self.some_float = 1.0
+        self.list_attr = [1.0, 2.0]
+        self._property_attr = 1337.0
+        self._name = "Service"
+        self.state = State.RUNNING
+        super().__init__(**kwargs)
+
+    @property
+    def name(self) -> str:
+        return self._name
+
+    @property
+    def property_attr(self) -> float:
+        return self._property_attr
+
+    @property_attr.setter
+    def property_attr(self, value: float) -> None:
+        self._property_attr = value
+
+
+CURRENT_STATE = Service().serialize()
+
+LOAD_STATE = {
+    "list_attr": {
+        "type": "list",
+        "value": [
+            {"type": "float", "value": 1.4, "readonly": False, "doc": None},
+            {"type": "float", "value": 2.0, "readonly": False, "doc": None},
+        ],
+        "readonly": False,
+        "doc": None,
+    },
+    "name": {
+        "type": "str",
+        "value": "Another name",
+        "readonly": True,
+        "doc": None,
+    },
+    "some_float": {
+        "type": "int",
+        "value": 10,
+        "readonly": False,
+        "doc": None,
+    },
+    "property_attr": {
+        "type": "float",
+        "value": 1337.1,
+        "readonly": False,
+        "doc": None,
+    },
+    "some_unit": {
+        "type": "Quantity",
+        "value": {"magnitude": 12.0, "unit": "A"},
+        "readonly": False,
+        "doc": None,
+    },
+    "state": {
+        "type": "ColouredEnum",
+        "value": "FAILED",
+        "readonly": True,
+        "doc": None,
+        "enum": {
+            "RUNNING": "#0000FF80",
+            "COMPLETED": "hsl(120, 100%, 50%)",
+            "FAILED": "hsla(0, 100%, 50%, 0.7)",
+        },
+    },
+    "subservice": {
+        "type": "DataService",
+        "value": {
+            "name": {
+                "type": "str",
+                "value": "SubService",
+                "readonly": False,
+                "doc": None,
+            }
+        },
+        "readonly": False,
+        "doc": None,
+    },
+    "removed_attr": {
+        "type": "str",
+        "value": "removed",
+        "readonly": False,
+        "doc": None,
+    },
+}
+
+
+def test_save_state(tmp_path: Path):
+    # Create a StateManager instance with a temporary file
+    file = tmp_path / "test_state.json"
+    manager = StateManager(service=Service(), filename=str(file))
+
+    # Trigger the saving action
+    manager.save_state()
+
+    # Now check that the file was written correctly
+    assert file.read_text() == json.dumps(CURRENT_STATE, indent=4)
+
+
+def test_load_state(tmp_path: Path, caplog: LogCaptureFixture):
+    # Create a StateManager instance with a temporary file
+    file = tmp_path / "test_state.json"
+
+    # Write a temporary JSON file to read back
+    with open(file, "w") as f:
+        json.dump(LOAD_STATE, f, indent=4)
+
+    service = Service()
+    manager = StateManager(service=service, filename=str(file))
+    manager.load_state()
+
+    assert service.some_unit == u.Quantity(12, "A")  # has changed
+    assert service.list_attr[0] == 1.4  # has changed
+    assert service.list_attr[1] == 2.0  # has not changed
+    assert (
+        service.property_attr == 1337
+    )  # has not changed as property has not @load_state decorator
+    assert service.state == State.FAILED  # has changed
+    assert service.name == "Service"  # has not changed as readonly
+    assert service.some_float == 1.0  # has not changed due to different type
+    assert service.subservice.name == "SubService"  # didn't change
+
+    assert "Service.some_unit changed to 12.0 A!" in caplog.text
+    assert "Attribute 'name' is read-only. Ignoring new value..." in caplog.text
+    assert (
+        "Attribute type of 'some_float' changed from 'int' to 'float'. "
+        "Ignoring value from JSON file..."
+    ) in caplog.text
+    assert (
+        "Attribute type of 'removed_attr' changed from 'str' to None. "
+        "Ignoring value from JSON file..." in caplog.text
+    )
+    assert "Value of attribute 'subservice.name' has not changed..." in caplog.text
+
+
+def test_filename_warning(tmp_path: Path, caplog: LogCaptureFixture):
+    file = tmp_path / "test_state.json"
+
+    service = Service(filename=str(file))
+    StateManager(service=service, filename=str(file))
+    assert f"Overwriting filename {str(file)!r} with {str(file)!r}." in caplog.text
+
+
+def test_filename_error(caplog: LogCaptureFixture):
+    service = Service()
+    manager = StateManager(service=service)
+
+    manager.save_state()
+    assert (
+        "State manager was not initialised with a filename. Skipping 'save_state'..."
+        in caplog.text
+    )
+
+
+def test_readonly_attribute(tmp_path: Path, caplog: LogCaptureFixture):
+    # Create a StateManager instance with a temporary file
+    file = tmp_path / "test_state.json"
+
+    # Write a temporary JSON file to read back
+    with open(file, "w") as f:
+        json.dump(LOAD_STATE, f, indent=4)
+
+    service = Service()
+    manager = StateManager(service=service, filename=str(file))
+    manager.load_state()
+    assert "Attribute 'name' is read-only. Ignoring new value..." in caplog.text
+
+
+def test_changed_type(tmp_path: Path, caplog: LogCaptureFixture):
+    # Create a StateManager instance with a temporary file
+    file = tmp_path / "test_state.json"
+
+    # Write a temporary JSON file to read back
+    with open(file, "w") as f:
+        json.dump(LOAD_STATE, f, indent=4)
+
+    service = Service()
+    manager = StateManager(service=service, filename=str(file))
+    manager.load_state()
+    assert (
+        "Attribute type of 'some_float' changed from 'int' to "
+        "'float'. Ignoring value from JSON file..."
+    ) in caplog.text
+
+
+def test_property_load_state(tmp_path: Path):
+    # Create a StateManager instance with a temporary file
+    file = tmp_path / "test_state.json"
+
+    LOAD_STATE = {
+        "name": {
+            "type": "str",
+            "value": "Some other name",
+            "readonly": False,
+            "doc": None,
+        },
+        "not_loadable_attr": {
+            "type": "str",
+            "value": "But I AM loadable!?",
+            "readonly": False,
+            "doc": None,
+        },
+    }
+
+    # Write a temporary JSON file to read back
+    with open(file, "w") as f:
+        json.dump(LOAD_STATE, f, indent=4)
+
+    class Service(pydase.DataService):
+        _name = "Service"
+        _not_loadable_attr = "Not loadable"
+
+        @property
+        def name(self) -> str:
+            return self._name
+
+        @name.setter
+        @load_state
+        def name(self, value: str) -> None:
+            self._name = value
+
+        @property
+        def not_loadable_attr(self) -> str:
+            return self._not_loadable_attr
+
+        @not_loadable_attr.setter
+        def not_loadable_attr(self, value: str) -> None:
+            self._not_loadable_attr = value
+
+        @property
+        def property_without_setter(self) -> None:
+            return
+
+    service_instance = Service()
+    StateManager(service_instance, filename=file).load_state()
+
+    assert service_instance.name == "Some other name"
+    assert service_instance.not_loadable_attr == "Not loadable"
+    assert not has_load_state_decorator(type(service_instance).property_without_setter)

tests/data_service/test_task_manager.py

@@ -0,0 +1,85 @@
+import logging
+
+from pytest import LogCaptureFixture
+
+import pydase
+
+logger = logging.getLogger()
+
+
+def test_autostart_task_callback(caplog: LogCaptureFixture) -> None:
+    class MyService(pydase.DataService):
+        def __init__(self) -> None:
+            self._autostart_tasks = {  # type: ignore
+                "my_task": (),
+                "my_other_task": (),
+            }
+            super().__init__()
+
+        async def my_task(self) -> None:
+            logger.info("Triggered task.")
+
+        async def my_other_task(self) -> None:
+            logger.info("Triggered other task.")
+
+    service = MyService()
+    service._task_manager.start_autostart_tasks()
+
+    assert "MyService.my_task changed to {}" in caplog.text
+    assert "MyService.my_other_task changed to {}" in caplog.text
+
+
+def test_DataService_subclass_autostart_task_callback(
+    caplog: LogCaptureFixture,
+) -> None:
+    class MySubService(pydase.DataService):
+        def __init__(self) -> None:
+            self._autostart_tasks = {  # type: ignore
+                "my_task": (),
+                "my_other_task": (),
+            }
+            super().__init__()
+
+        async def my_task(self) -> None:
+            logger.info("Triggered task.")
+
+        async def my_other_task(self) -> None:
+            logger.info("Triggered other task.")
+
+    class MyService(pydase.DataService):
+        sub_service = MySubService()
+
+    service = MyService()
+    service._task_manager.start_autostart_tasks()
+
+    assert "MyService.sub_service.my_task changed to {}" in caplog.text
+    assert "MyService.sub_service.my_other_task changed to {}" in caplog.text
+
+
+def test_DataServiceList_subclass_autostart_task_callback(
+    caplog: LogCaptureFixture,
+) -> None:
+    class MySubService(pydase.DataService):
+        def __init__(self) -> None:
+            self._autostart_tasks = {  # type: ignore
+                "my_task": (),
+                "my_other_task": (),
+            }
+            super().__init__()
+
+        async def my_task(self) -> None:
+            logger.info("Triggered task.")
+
+        async def my_other_task(self) -> None:
+            logger.info("Triggered other task.")
+
+    class MyService(pydase.DataService):
+        sub_services_list = [MySubService() for i in range(2)]
+
+    service = MyService()
+    service._task_manager.start_autostart_tasks()
+
+    assert "MyService.sub_services_list[0].my_task changed to {}" in caplog.text
+    assert "MyService.sub_services_list[0].my_other_task changed to {}" in caplog.text
+    assert "MyService.sub_services_list[1].my_task changed to {}" in caplog.text
+    assert "MyService.sub_services_list[1].my_other_task changed to {}" in caplog.text

tests/server/test_server.py

@@ -0,0 +1,35 @@
+import signal
+
+from pytest_mock import MockerFixture
+
+import pydase
+
+
+def test_signal_handling(mocker: MockerFixture):
+    # Mock os._exit and signal.signal
+    mock_exit = mocker.patch("os._exit")
+    mock_signal = mocker.patch("signal.signal")
+
+    class MyService(pydase.DataService):
+        pass
+
+    # Instantiate your server object
+    server = pydase.Server(MyService())
+
+    # Call the method to install signal handlers
+    server.install_signal_handlers()
+
+    # Check if the signal handlers were registered correctly
+    assert mock_signal.call_args_list == [
+        mocker.call(signal.SIGINT, server.handle_exit),
+        mocker.call(signal.SIGTERM, server.handle_exit),
+    ]
+
+    # Simulate receiving a SIGINT signal for the first time
+    server.handle_exit(signal.SIGINT, None)
+    assert server.should_exit  # assuming should_exit is public
+    mock_exit.assert_not_called()
+
+    # Simulate receiving a SIGINT signal for the second time
+    server.handle_exit(signal.SIGINT, None)
+    mock_exit.assert_called_once_with(1)

tests/test_DataServiceList.py

@@ -1,101 +0,0 @@
-from pytest import CaptureFixture
-
-from pydase import DataService
-
-
-def test_class_list_attribute(capsys: CaptureFixture) -> None:
-    class ServiceClass(DataService):
-        attr = [0, 1]
-
-    service_instance = ServiceClass()
-
-    service_instance.attr[0] = 1337
-    captured = capsys.readouterr()
-    assert captured.out == "ServiceClass.attr[0] = 1337\n"
-
-
-def test_instance_list_attribute(capsys: CaptureFixture) -> None:
-    class SubClass(DataService):
-        name = "SubClass"
-
-    class ServiceClass(DataService):
-        def __init__(self) -> None:
-            self.attr = [0, SubClass()]
-            super().__init__()
-
-    service_instance = ServiceClass()
-
-    _ = capsys.readouterr()
-
-    service_instance.attr[0] = "Hello"
-    captured = capsys.readouterr()
-    assert captured.out == "ServiceClass.attr[0] = Hello\n"
-
-    service_instance.attr[1] = SubClass()
-    captured = capsys.readouterr()
-    assert (
-        captured.out.strip()
-        == "ServiceClass.attr[1] = {'name': {'type': 'str', 'value': 'SubClass',"
-        " 'readonly': False, 'doc': None}}"
-    )
-
-
-def test_reused_instance_list_attribute(capsys: CaptureFixture) -> None:
-    some_list = [0, 1, 2]
-
-    class ServiceClass(DataService):
-        def __init__(self) -> None:
-            self.attr = some_list
-            self.attr_2 = some_list
-            self.attr_3 = [0, 1, 2]
-            super().__init__()
-
-    service_instance = ServiceClass()
-
-    service_instance.attr[0] = 20
-    captured = capsys.readouterr()
-
-    assert service_instance.attr == service_instance.attr_2
-    assert service_instance.attr != service_instance.attr_3
-    expected_output = sorted(
-        [
-            "ServiceClass.attr[0] = 20",
-            "ServiceClass.attr_2[0] = 20",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
-
-
-def test_nested_reused_instance_list_attribute(capsys: CaptureFixture) -> None:
-    some_list = [0, 1, 2]
-
-    class SubClass(DataService):
-        attr_list = some_list
-
-        def __init__(self) -> None:
-            self.attr_list_2 = some_list
-            super().__init__()
-
-    class ServiceClass(DataService):
-        def __init__(self) -> None:
-            self.attr = some_list
-            self.subclass = SubClass()
-            super().__init__()
-
-    service_instance = ServiceClass()
-
-    _ = capsys.readouterr()
-    service_instance.attr[0] = 20
-    captured = capsys.readouterr()
-
-    assert service_instance.attr == service_instance.subclass.attr_list
-    expected_output = sorted(
-        [
-            "ServiceClass.subclass.attr_list_2[0] = 20",
-            "ServiceClass.subclass.attr_list[0] = 20",
-            "ServiceClass.attr[0] = 20",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output

tests/test_DataService_attribute_callbacks.py

@@ -1,9 +1,9 @@
-from pytest import CaptureFixture
+from pytest import LogCaptureFixture
 
 from pydase import DataService
 
 
-def test_class_attributes(capsys: CaptureFixture) -> None:
+def test_class_attributes(caplog: LogCaptureFixture) -> None:
     class SubClass(DataService):
         name = "Hello"
 
@@ -11,14 +11,12 @@ def test_class_attributes(capsys: CaptureFixture) -> None:
         attr_1 = SubClass()
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
     service_instance.attr_1.name = "Hi"
 
-    captured = capsys.readouterr()
-    assert captured.out.strip() == "ServiceClass.attr_1.name = Hi"
+    assert "ServiceClass.attr_1.name changed to Hi" in caplog.text
 
 
-def test_instance_attributes(capsys: CaptureFixture) -> None:
+def test_instance_attributes(caplog: LogCaptureFixture) -> None:
     class SubClass(DataService):
         name = "Hello"
 
@@ -28,25 +26,22 @@ def test_instance_attributes(capsys: CaptureFixture) -> None:
             super().__init__()
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
     service_instance.attr_1.name = "Hi"
 
-    captured = capsys.readouterr()
-    assert captured.out.strip() == "ServiceClass.attr_1.name = Hi"
+    assert "ServiceClass.attr_1.name changed to Hi" in caplog.text
 
 
-def test_class_attribute(capsys: CaptureFixture) -> None:
+def test_class_attribute(caplog: LogCaptureFixture) -> None:
     class ServiceClass(DataService):
         attr = 0
 
     service_instance = ServiceClass()
 
     service_instance.attr = 1
-    captured = capsys.readouterr()
-    assert captured.out == "ServiceClass.attr = 1\n"
+    assert "ServiceClass.attr changed to 1" in caplog.text
 
 
-def test_instance_attribute(capsys: CaptureFixture) -> None:
+def test_instance_attribute(caplog: LogCaptureFixture) -> None:
     class ServiceClass(DataService):
         def __init__(self) -> None:
             self.attr = "Hello World"
@@ -55,11 +50,10 @@ def test_instance_attribute(capsys: CaptureFixture) -> None:
     service_instance = ServiceClass()
 
     service_instance.attr = "Hello"
-    captured = capsys.readouterr()
-    assert captured.out == "ServiceClass.attr = Hello\n"
+    assert "ServiceClass.attr changed to Hello" in caplog.text
 
 
-def test_reused_instance_attributes(capsys: CaptureFixture) -> None:
+def test_reused_instance_attributes(caplog: LogCaptureFixture) -> None:
     class SubClass(DataService):
         name = "Hello"
 
@@ -72,22 +66,14 @@ def test_reused_instance_attributes(capsys: CaptureFixture) -> None:
             super().__init__()
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
     service_instance.attr_1.name = "Hi"
 
-    captured = capsys.readouterr()
     assert service_instance.attr_1 == service_instance.attr_2
-    expected_output = sorted(
-        [
-            "ServiceClass.attr_1.name = Hi",
-            "ServiceClass.attr_2.name = Hi",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr_1.name changed to Hi" in caplog.text
+    assert "ServiceClass.attr_2.name changed to Hi" in caplog.text
 
 
-def test_reused_attributes_mixed(capsys: CaptureFixture) -> None:
+def test_reused_attributes_mixed(caplog: LogCaptureFixture) -> None:
     class SubClass(DataService):
         pass
 
@@ -101,22 +87,14 @@ def test_reused_attributes_mixed(capsys: CaptureFixture) -> None:
             super().__init__()
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
     service_instance.attr_1.name = "Hi"
 
-    captured = capsys.readouterr()
     assert service_instance.attr_1 == service_instance.attr_2
-    expected_output = sorted(
-        [
-            "ServiceClass.attr_1.name = Hi",
-            "ServiceClass.attr_2.name = Hi",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr_1.name changed to Hi" in caplog.text
+    assert "ServiceClass.attr_2.name changed to Hi" in caplog.text
 
 
-def test_nested_class_attributes(capsys: CaptureFixture) -> None:
+def test_nested_class_attributes(caplog: LogCaptureFixture) -> None:
     class SubSubSubClass(DataService):
         name = "Hello"
 
@@ -133,26 +111,18 @@ def test_nested_class_attributes(capsys: CaptureFixture) -> None:
         attr = SubClass()
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
     service_instance.attr.attr.attr.name = "Hi"
     service_instance.attr.attr.name = "Hou"
     service_instance.attr.name = "foo"
     service_instance.name = "bar"
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr.attr.attr.name = Hi",
-            "ServiceClass.attr.attr.name = Hou",
-            "ServiceClass.attr.name = foo",
-            "ServiceClass.name = bar",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr.attr.attr.name changed to Hi" in caplog.text
+    assert "ServiceClass.attr.attr.name changed to Hou" in caplog.text
+    assert "ServiceClass.attr.name changed to foo" in caplog.text
+    assert "ServiceClass.name changed to bar" in caplog.text
 
 
-def test_nested_instance_attributes(capsys: CaptureFixture) -> None:
+def test_nested_instance_attributes(caplog: LogCaptureFixture) -> None:
     class SubSubSubClass(DataService):
         name = "Hello"
 
@@ -175,26 +145,18 @@ def test_nested_instance_attributes(capsys: CaptureFixture) -> None:
             super().__init__()
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
     service_instance.attr.attr.attr.name = "Hi"
     service_instance.attr.attr.name = "Hou"
     service_instance.attr.name = "foo"
     service_instance.name = "bar"
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr.attr.attr.name = Hi",
-            "ServiceClass.attr.attr.name = Hou",
-            "ServiceClass.attr.name = foo",
-            "ServiceClass.name = bar",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr.attr.attr.name changed to Hi" in caplog.text
+    assert "ServiceClass.attr.attr.name changed to Hou" in caplog.text
+    assert "ServiceClass.attr.name changed to foo" in caplog.text
+    assert "ServiceClass.name changed to bar" in caplog.text
 
 
-def test_advanced_nested_class_attributes(capsys: CaptureFixture) -> None:
+def test_advanced_nested_class_attributes(caplog: LogCaptureFixture) -> None:
     class SubSubSubClass(DataService):
         name = "Hello"
 
@@ -209,32 +171,17 @@ def test_advanced_nested_class_attributes(capsys: CaptureFixture) -> None:
         subattr = SubSubClass()
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
     service_instance.attr.attr.attr.name = "Hi"
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr.attr.attr.name = Hi",
-            "ServiceClass.subattr.attr.name = Hi",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr.attr.attr.name changed to Hi" in caplog.text
+    assert "ServiceClass.subattr.attr.name changed to Hi" in caplog.text
     service_instance.subattr.attr.name = "Ho"
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr.attr.attr.name = Ho",
-            "ServiceClass.subattr.attr.name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr.attr.attr.name changed to Ho" in caplog.text
+    assert "ServiceClass.subattr.attr.name changed to Ho" in caplog.text
 
 
-def test_advanced_nested_instance_attributes(capsys: CaptureFixture) -> None:
+def test_advanced_nested_instance_attributes(caplog: LogCaptureFixture) -> None:
     class SubSubSubClass(DataService):
         name = "Hello"
 
@@ -257,32 +204,19 @@ def test_advanced_nested_instance_attributes(capsys: CaptureFixture) -> None:
             super().__init__()
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
+
     service_instance.attr.attr.attr.name = "Hi"
+    assert "ServiceClass.attr.attr.attr.name changed to Hi" in caplog.text
+    assert "ServiceClass.subattr.attr.name changed to Hi" in caplog.text
+    caplog.clear()
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr.attr.attr.name = Hi",
-            "ServiceClass.subattr.attr.name = Hi",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
     service_instance.subattr.attr.name = "Ho"
-
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr.attr.attr.name = Ho",
-            "ServiceClass.subattr.attr.name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr.attr.attr.name changed to Ho" in caplog.text
+    assert "ServiceClass.subattr.attr.name changed to Ho" in caplog.text
+    caplog.clear()
 
 
-def test_advanced_nested_attributes_mixed(capsys: CaptureFixture) -> None:
+def test_advanced_nested_attributes_mixed(caplog: LogCaptureFixture) -> None:
     class SubSubClass(DataService):
         name = "Hello"
 
@@ -310,44 +244,28 @@ def test_advanced_nested_attributes_mixed(capsys: CaptureFixture) -> None:
     # instances of SubSubClass are unequal
     assert service_instance.attr.attr_1 != service_instance.class_attr.class_attr
 
-    _ = capsys.readouterr()
-
     service_instance.class_attr.class_attr.name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.class_attr.class_attr.name = Ho",
-            "ServiceClass.attr.class_attr.name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.class_attr.class_attr.name changed to Ho" in caplog.text
+    assert "ServiceClass.attr.class_attr.name changed to Ho" in caplog.text
+    caplog.clear()
 
     service_instance.class_attr.attr_1.name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(["ServiceClass.class_attr.attr_1.name = Ho"])
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.class_attr.attr_1.name changed to Ho" in caplog.text
+    assert "ServiceClass.attr.attr_1.name changed to Ho" not in caplog.text
+    caplog.clear()
 
     service_instance.attr.class_attr.name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr.class_attr.name = Ho",
-            "ServiceClass.class_attr.class_attr.name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.class_attr.class_attr.name changed to Ho" in caplog.text
+    assert "ServiceClass.attr.class_attr.name changed to Ho" in caplog.text
+    caplog.clear()
 
     service_instance.attr.attr_1.name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(["ServiceClass.attr.attr_1.name = Ho"])
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr.attr_1.name changed to Ho" in caplog.text
+    assert "ServiceClass.class_attr.attr_1.name changed to Ho" not in caplog.text
+    caplog.clear()
 
 
-def test_class_list_attributes(capsys: CaptureFixture) -> None:
+def test_class_list_attributes(caplog: LogCaptureFixture) -> None:
     class SubClass(DataService):
         name = "Hello"
 
@@ -359,59 +277,36 @@ def test_class_list_attributes(capsys: CaptureFixture) -> None:
         attr = subclass_instance
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
 
     assert service_instance.attr_list[0] != service_instance.attr_list[1]
 
     service_instance.attr_list[0].name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr_list[0].name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr_list[0].name changed to Ho" in caplog.text
+    assert "ServiceClass.attr_list[1].name changed to Ho" not in caplog.text
+    caplog.clear()
 
     service_instance.attr_list[1].name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr_list[1].name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr_list[0].name changed to Ho" not in caplog.text
+    assert "ServiceClass.attr_list[1].name changed to Ho" in caplog.text
+    caplog.clear()
 
     assert service_instance.attr_list_2[0] == service_instance.attr
     assert service_instance.attr_list_2[0] == service_instance.attr_list_2[1]
 
     service_instance.attr_list_2[0].name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr_list_2[0].name = Ho",
-            "ServiceClass.attr_list_2[1].name = Ho",
-            "ServiceClass.attr.name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr_list_2[0].name changed to Ho" in caplog.text
+    assert "ServiceClass.attr_list_2[1].name changed to Ho" in caplog.text
+    assert "ServiceClass.attr.name changed to Ho" in caplog.text
+    caplog.clear()
 
     service_instance.attr_list_2[1].name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr_list_2[0].name = Ho",
-            "ServiceClass.attr_list_2[1].name = Ho",
-            "ServiceClass.attr.name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr_list_2[0].name changed to Ho" in caplog.text
+    assert "ServiceClass.attr_list_2[1].name changed to Ho" in caplog.text
+    assert "ServiceClass.attr.name changed to Ho" in caplog.text
+    caplog.clear()
 
 
-def test_nested_class_list_attributes(capsys: CaptureFixture) -> None:
+def test_nested_class_list_attributes(caplog: LogCaptureFixture) -> None:
     class SubSubClass(DataService):
         name = "Hello"
 
@@ -425,34 +320,21 @@ def test_nested_class_list_attributes(capsys: CaptureFixture) -> None:
         subattr = subsubclass_instance
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
 
     assert service_instance.attr[0].attr_list[0] == service_instance.subattr
 
     service_instance.attr[0].attr_list[0].name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr[0].attr_list[0].name = Ho",
-            "ServiceClass.subattr.name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr[0].attr_list[0].name changed to Ho" in caplog.text
+    assert "ServiceClass.subattr.name changed to Ho" in caplog.text
+    caplog.clear()
 
     service_instance.subattr.name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr[0].attr_list[0].name = Ho",
-            "ServiceClass.subattr.name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr[0].attr_list[0].name changed to Ho" in caplog.text
+    assert "ServiceClass.subattr.name changed to Ho" in caplog.text
+    caplog.clear()
 
 
-def test_instance_list_attributes(capsys: CaptureFixture) -> None:
+def test_instance_list_attributes(caplog: LogCaptureFixture) -> None:
     class SubClass(DataService):
         name = "Hello"
 
@@ -466,63 +348,42 @@ def test_instance_list_attributes(capsys: CaptureFixture) -> None:
             super().__init__()
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
 
     assert service_instance.attr_list[0] != service_instance.attr_list[1]
 
     service_instance.attr_list[0].name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(["ServiceClass.attr_list[0].name = Ho"])
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr_list[0].name changed to Ho" in caplog.text
+    assert "ServiceClass.attr_list[1].name changed to Ho" not in caplog.text
+    caplog.clear()
 
     service_instance.attr_list[1].name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(["ServiceClass.attr_list[1].name = Ho"])
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr_list[0].name changed to Ho" not in caplog.text
+    assert "ServiceClass.attr_list[1].name changed to Ho" in caplog.text
+    caplog.clear()
 
     assert service_instance.attr_list_2[0] == service_instance.attr
     assert service_instance.attr_list_2[0] == service_instance.attr_list_2[1]
 
     service_instance.attr_list_2[0].name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr.name = Ho",
-            "ServiceClass.attr_list_2[0].name = Ho",
-            "ServiceClass.attr_list_2[1].name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr.name changed to Ho" in caplog.text
+    assert "ServiceClass.attr_list_2[0].name changed to Ho" in caplog.text
+    assert "ServiceClass.attr_list_2[1].name changed to Ho" in caplog.text
+    caplog.clear()
 
     service_instance.attr_list_2[1].name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr.name = Ho",
-            "ServiceClass.attr_list_2[0].name = Ho",
-            "ServiceClass.attr_list_2[1].name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr.name changed to Ho" in caplog.text
+    assert "ServiceClass.attr_list_2[0].name changed to Ho" in caplog.text
+    assert "ServiceClass.attr_list_2[1].name changed to Ho" in caplog.text
+    caplog.clear()
 
     service_instance.attr.name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr.name = Ho",
-            "ServiceClass.attr_list_2[0].name = Ho",
-            "ServiceClass.attr_list_2[1].name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr.name changed to Ho" in caplog.text
+    assert "ServiceClass.attr_list_2[0].name changed to Ho" in caplog.text
+    assert "ServiceClass.attr_list_2[1].name changed to Ho" in caplog.text
+    caplog.clear()
 
 
-def test_nested_instance_list_attributes(capsys: CaptureFixture) -> None:
+def test_nested_instance_list_attributes(caplog: LogCaptureFixture) -> None:
     class SubSubClass(DataService):
         name = "Hello"
 
@@ -541,28 +402,15 @@ def test_nested_instance_list_attributes(capsys: CaptureFixture) -> None:
             super().__init__()
 
     service_instance = ServiceClass()
-    _ = capsys.readouterr()
 
     assert service_instance.attr[0].attr_list[0] == service_instance.class_attr
 
     service_instance.attr[0].attr_list[0].name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr[0].attr_list[0].name = Ho",
-            "ServiceClass.class_attr.name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr[0].attr_list[0].name changed to Ho" in caplog.text
+    assert "ServiceClass.class_attr.name changed to Ho" in caplog.text
+    caplog.clear()
 
     service_instance.class_attr.name = "Ho"
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.attr[0].attr_list[0].name = Ho",
-            "ServiceClass.class_attr.name = Ho",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.attr[0].attr_list[0].name changed to Ho" in caplog.text
+    assert "ServiceClass.class_attr.name changed to Ho" in caplog.text
+    caplog.clear()

tests/test_properties.py

@@ -1,9 +1,9 @@
-from pytest import CaptureFixture
+from pytest import LogCaptureFixture
 
 from pydase import DataService
 
 
-def test_properties(capsys: CaptureFixture) -> None:
+def test_properties(caplog: LogCaptureFixture) -> None:
     class ServiceClass(DataService):
         _voltage = 10.0
         _current = 1.0
@@ -31,30 +31,17 @@ def test_properties(capsys: CaptureFixture) -> None:
     test_service = ServiceClass()
     test_service.voltage = 1
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.power = 1.0",
-            "ServiceClass.voltage = 1.0",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.power changed to 1.0" in caplog.text
+    assert "ServiceClass.voltage changed to 1.0" in caplog.text
+    caplog.clear()
 
     test_service.current = 12.0
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.power = 12.0",
-            "ServiceClass.current = 12.0",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.power changed to 12.0" in caplog.text
+    assert "ServiceClass.current changed to 12.0" in caplog.text
 
 
-def test_nested_properties(capsys: CaptureFixture) -> None:
+def test_nested_properties(caplog: LogCaptureFixture) -> None:
     class SubSubClass(DataService):
         name = "Hello"
 
@@ -77,45 +64,31 @@ def test_nested_properties(capsys: CaptureFixture) -> None:
     test_service = ServiceClass()
     test_service.name = "Peepz"
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.name = Peepz",
-            "ServiceClass.sub_name = Hello Peepz",
-            "ServiceClass.subsub_name = Hello Peepz",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.name changed to Peepz" in caplog.text
+    assert "ServiceClass.sub_name changed to Hello Peepz" in caplog.text
+    assert "ServiceClass.subsub_name changed to Hello Peepz" in caplog.text
+    caplog.clear()
 
     test_service.class_attr.name = "Hi"
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.sub_name = Hi Peepz",
-            "ServiceClass.subsub_name = Hello Peepz",  # registers subclass changes
-            "ServiceClass.class_attr.name = Hi",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.sub_name changed to Hi Peepz" in caplog.text
+    assert (
+        "ServiceClass.subsub_name changed to Hello Peepz" in caplog.text
+    )  # registers subclass changes
+    assert "ServiceClass.class_attr.name changed to Hi" in caplog.text
+    caplog.clear()
 
     test_service.class_attr.class_attr.name = "Ciao"
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.sub_name = Hi Peepz",  # registers subclass changes
-            "ServiceClass.subsub_name = Ciao Peepz",
-            "ServiceClass.class_attr.class_attr.name = Ciao",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert (
+        "ServiceClass.sub_name changed to Hi Peepz" in caplog.text
+    )  # registers subclass changes
+    assert "ServiceClass.subsub_name changed to Ciao Peepz" in caplog.text
+    assert "ServiceClass.class_attr.class_attr.name changed to Ciao" in caplog.text
+    caplog.clear()
 
 
-def test_simple_list_properties(capsys: CaptureFixture) -> None:
+def test_simple_list_properties(caplog: LogCaptureFixture) -> None:
     class ServiceClass(DataService):
         list = ["Hello", "Ciao"]
         name = "World"
@@ -127,30 +100,17 @@ def test_simple_list_properties(capsys: CaptureFixture) -> None:
     test_service = ServiceClass()
     test_service.name = "Peepz"
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.name = Peepz",
-            "ServiceClass.total_name = Hello Peepz",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.name changed to Peepz" in caplog.text
+    assert "ServiceClass.total_name changed to Hello Peepz" in caplog.text
+    caplog.clear()
 
     test_service.list[0] = "Hi"
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.total_name = Hi Peepz",
-            "ServiceClass.list[0] = Hi",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.total_name changed to Hi Peepz" in caplog.text
+    assert "ServiceClass.list[0] changed to Hi" in caplog.text
 
 
-def test_class_list_properties(capsys: CaptureFixture) -> None:
+def test_class_list_properties(caplog: LogCaptureFixture) -> None:
     class SubClass(DataService):
         name = "Hello"
 
@@ -165,73 +125,17 @@ def test_class_list_properties(capsys: CaptureFixture) -> None:
     test_service = ServiceClass()
     test_service.name = "Peepz"
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.name = Peepz",
-            "ServiceClass.total_name = Hello Peepz",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.name changed to Peepz" in caplog.text
+    assert "ServiceClass.total_name changed to Hello Peepz" in caplog.text
+    caplog.clear()
 
     test_service.list[0].name = "Hi"
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.total_name = Hi Peepz",
-            "ServiceClass.list[0].name = Hi",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
+    assert "ServiceClass.total_name changed to Hi Peepz" in caplog.text
+    assert "ServiceClass.list[0].name changed to Hi" in caplog.text
 
 
-def test_subclass_properties(capsys: CaptureFixture) -> None:
-    class SubClass(DataService):
-        name = "Hello"
-        _voltage = 10.0
-        _current = 1.0
-
-        @property
-        def power(self) -> float:
-            return self._voltage * self.current
-
-        @property
-        def voltage(self) -> float:
-            return self._voltage
-
-        @voltage.setter
-        def voltage(self, value: float) -> None:
-            self._voltage = value
-
-        @property
-        def current(self) -> float:
-            return self._current
-
-        @current.setter
-        def current(self, value: float) -> None:
-            self._current = value
-
-    class ServiceClass(DataService):
-        class_attr = SubClass()
-
-    test_service = ServiceClass()
-    test_service.class_attr.voltage = 10.0
-
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        [
-            "ServiceClass.class_attr.voltage = 10.0",
-            "ServiceClass.class_attr.power = 10.0",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))
-    assert actual_output == expected_output
-
-
-def test_subclass_properties(capsys: CaptureFixture) -> None:
+def test_subclass_properties(caplog: LogCaptureFixture) -> None:
     class SubClass(DataService):
         name = "Hello"
         _voltage = 10.0
@@ -267,21 +171,15 @@ def test_subclass_properties(capsys: CaptureFixture) -> None:
     test_service = ServiceClass()
     test_service.class_attr.voltage = 10.0
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        {
-            "ServiceClass.class_attr.voltage = 10.0",
-            "ServiceClass.class_attr.power = 10.0",
-            "ServiceClass.voltage = 10.0",
-        }
-    )
     # using a set here as "ServiceClass.voltage = 10.0" is emitted twice. Once for
     # changing voltage, and once for changing power.
-    actual_output = sorted(set(captured.out.strip().split("\n")))
-    assert actual_output == expected_output
+    assert "ServiceClass.class_attr.voltage changed to 10.0" in caplog.text
+    assert "ServiceClass.class_attr.power changed to 10.0" in caplog.text
+    assert "ServiceClass.voltage changed to 10.0" in caplog.text
+    caplog.clear()
 
 
-def test_subclass_properties_2(capsys: CaptureFixture) -> None:
+def test_subclass_properties_2(caplog: LogCaptureFixture) -> None:
     class SubClass(DataService):
         name = "Hello"
         _voltage = 10.0
@@ -317,24 +215,17 @@ def test_subclass_properties_2(capsys: CaptureFixture) -> None:
     test_service = ServiceClass()
     test_service.class_attr[1].current = 10.0
 
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        {
-            "ServiceClass.class_attr[1].current = 10.0",
-            "ServiceClass.class_attr[1].power = 100.0",
-            "ServiceClass.voltage = 10.0",
-        }
-    )
     # using a set here as "ServiceClass.voltage = 10.0" is emitted twice. Once for
     # changing current, and once for changing power. Note that the voltage property is
     # only dependent on class_attr[0] but still emits an update notification. This is
     # because every time any item in the list `test_service.class_attr` is changed,
     # a notification will be emitted.
-    actual_output = sorted(set(captured.out.strip().split("\n")))
-    assert actual_output == expected_output
+    assert "ServiceClass.class_attr[1].current changed to 10.0" in caplog.text
+    assert "ServiceClass.class_attr[1].power changed to 100.0" in caplog.text
+    assert "ServiceClass.voltage changed to 10.0" in caplog.text
 
 
-def test_subsubclass_properties(capsys: CaptureFixture) -> None:
+def test_subsubclass_properties(caplog: LogCaptureFixture) -> None:
     class SubSubClass(DataService):
         _voltage = 10.0
 
@@ -364,21 +255,18 @@ def test_subsubclass_properties(capsys: CaptureFixture) -> None:
     test_service = ServiceClass()
 
     test_service.class_attr[1].class_attr.voltage = 100.0
-    captured = capsys.readouterr()
-    expected_output = sorted(
-        {
-            "ServiceClass.class_attr[0].class_attr.voltage = 100.0",
-            "ServiceClass.class_attr[1].class_attr.voltage = 100.0",
-            "ServiceClass.class_attr[0].power = 50.0",
-            "ServiceClass.class_attr[1].power = 50.0",
-            "ServiceClass.power = 50.0",
-        }
+    assert (
+        "ServiceClass.class_attr[0].class_attr.voltage changed to 100.0" in caplog.text
     )
-    actual_output = sorted(set(captured.out.strip().split("\n")))
-    assert actual_output == expected_output
+    assert (
+        "ServiceClass.class_attr[1].class_attr.voltage changed to 100.0" in caplog.text
+    )
+    assert "ServiceClass.class_attr[0].power changed to 50.0" in caplog.text
+    assert "ServiceClass.class_attr[1].power changed to 50.0" in caplog.text
+    assert "ServiceClass.power changed to 50.0" in caplog.text
 
 
-def test_subsubclass_instance_properties(capsys: CaptureFixture) -> None:
+def test_subsubclass_instance_properties(caplog: LogCaptureFixture) -> None:
     class SubSubClass(DataService):
         def __init__(self) -> None:
             self._voltage = 10.0
@@ -412,16 +300,9 @@ def test_subsubclass_instance_properties(capsys: CaptureFixture) -> None:
     test_service = ServiceClass()
 
     test_service.class_attr[1].attr[0].voltage = 100.0
-    captured = capsys.readouterr()
     # again, changing an item in a list will trigger the callbacks. This is why a
     # notification for `ServiceClass.power` is emitted although it did not change its
     # value
-    expected_output = sorted(
-        {
-            "ServiceClass.class_attr[1].attr[0].voltage = 100.0",
-            "ServiceClass.class_attr[1].power = 50.0",
-            "ServiceClass.power = 5.0",
-        }
-    )
-    actual_output = sorted(set(captured.out.strip().split("\n")))
-    assert actual_output == expected_output
+    assert "ServiceClass.class_attr[1].attr[0].voltage changed to 100.0" in caplog.text
+    assert "ServiceClass.class_attr[1].power changed to 50.0" in caplog.text
+    assert "ServiceClass.power changed to 5.0" in caplog.text

tests/test_units.py

@@ -1,12 +1,12 @@
 from typing import Any
 
-from pytest import CaptureFixture
+from pytest import LogCaptureFixture
 
 import pydase.units as u
 from pydase.data_service.data_service import DataService
 
 
-def test_DataService_setattr(capsys: CaptureFixture) -> None:
+def test_DataService_setattr(caplog: LogCaptureFixture) -> None:
     class ServiceClass(DataService):
         voltage = 1.0 * u.units.V
         _current: u.Quantity = 1.0 * u.units.mA
@@ -28,31 +28,17 @@ def test_DataService_setattr(capsys: CaptureFixture) -> None:
 
     assert service.voltage == 10.0 * u.units.V  # type: ignore
     assert service.current == 1.5 * u.units.mA
-    captured = capsys.readouterr()
 
-    expected_output = sorted(
-        [
-            "ServiceClass.voltage = 10.0 V",
-            "ServiceClass.current = 1.5 mA",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))  # type: ignore
-    assert actual_output == expected_output
+    assert "ServiceClass.voltage changed to 10.0 V" in caplog.text
+    assert "ServiceClass.current changed to 1.5 mA" in caplog.text
 
     service.voltage = 12.0 * u.units.V  # type: ignore
     service.current = 1.51 * u.units.A
     assert service.voltage == 12.0 * u.units.V  # type: ignore
     assert service.current == 1.51 * u.units.A
-    captured = capsys.readouterr()
 
-    expected_output = sorted(
-        [
-            "ServiceClass.voltage = 12.0 V",
-            "ServiceClass.current = 1.51 A",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))  # type: ignore
-    assert actual_output == expected_output
+    assert "ServiceClass.voltage changed to 12.0 V" in caplog.text
+    assert "ServiceClass.current changed to 1.51 A" in caplog.text
 
 
 def test_convert_to_quantity() -> None:
@@ -62,7 +48,7 @@ def test_convert_to_quantity() -> None:
     assert u.convert_to_quantity(1.0 * u.units.mV) == 1.0 * u.units.mV
 
 
-def test_update_DataService_attribute(capsys: CaptureFixture) -> None:
+def test_update_DataService_attribute(caplog: LogCaptureFixture) -> None:
     class ServiceClass(DataService):
         voltage = 1.0 * u.units.V
         _current: u.Quantity = 1.0 * u.units.mA
@@ -80,36 +66,59 @@ def test_update_DataService_attribute(capsys: CaptureFixture) -> None:
     service.update_DataService_attribute(
         path_list=[], attr_name="voltage", value=1.0 * u.units.mV
     )
-    captured = capsys.readouterr()
 
-    expected_output = sorted(
-        [
-            "ServiceClass.voltage = 1.0 mV",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))  # type: ignore
-    assert actual_output == expected_output
+    assert "ServiceClass.voltage changed to 1.0 mV" in caplog.text
 
     service.update_DataService_attribute(path_list=[], attr_name="voltage", value=2)
-    captured = capsys.readouterr()
 
-    expected_output = sorted(
-        [
-            "ServiceClass.voltage = 2.0 mV",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))  # type: ignore
-    assert actual_output == expected_output
+    assert "ServiceClass.voltage changed to 2.0 mV" in caplog.text
 
     service.update_DataService_attribute(
         path_list=[], attr_name="voltage", value={"magnitude": 123, "unit": "kV"}
     )
-    captured = capsys.readouterr()
 
-    expected_output = sorted(
-        [
-            "ServiceClass.voltage = 123.0 kV",
-        ]
-    )
-    actual_output = sorted(captured.out.strip().split("\n"))  # type: ignore
-    assert actual_output == expected_output
+    assert "ServiceClass.voltage changed to 123.0 kV" in caplog.text
+
+
+def test_autoconvert_offset_to_baseunit() -> None:
+    import pint
+
+    assert u.units.autoconvert_offset_to_baseunit is True
+
+    try:
+        quantity = 10 * u.units.degC
+    except pint.errors.OffsetUnitCalculusError as exc:
+        assert False, f"Offset unit raises exception {exc}"
+
+
+def test_loading_from_json(caplog: LogCaptureFixture) -> None:
+    """This function tests if the quantity read from the json description is actually
+    passed as a quantity to the property setter."""
+    JSON_DICT = {
+        "some_unit": {
+            "type": "Quantity",
+            "value": {"magnitude": 10.0, "unit": "A"},
+            "readonly": False,
+            "doc": None,
+        }
+    }
+
+    class ServiceClass(DataService):
+        def __init__(self):
+            self._unit: u.Quantity = 1 * u.units.A
+            super().__init__()
+
+        @property
+        def some_unit(self) -> u.Quantity:
+            return self._unit
+
+        @some_unit.setter
+        def some_unit(self, value: u.Quantity) -> None:
+            assert isinstance(value, u.Quantity)
+            self._unit = value
+
+    service = ServiceClass()
+
+    service.load_DataService_from_JSON(JSON_DICT)
+
+    assert "ServiceClass.some_unit changed to 10.0 A" in caplog.text

tests/utils/test_helpers.py

@@ -1,70 +1,6 @@
 import pytest
 
-from pydase.utils.helpers import (
-    extract_dict_or_list_entry,
-    get_nested_value_from_DataService_by_path_and_key,
-    is_property_attribute,
-)
-
-# Sample data for the tests
-data_sample = {
-    "attr1": {"type": "bool", "value": False, "readonly": False, "doc": None},
-    "class_attr": {
-        "type": "MyClass",
-        "value": {"sub_attr": {"type": "float", "value": 20.5}},
-    },
-    "list_attr": {
-        "type": "list",
-        "value": [
-            {"type": "int", "value": 0, "readonly": False, "doc": None},
-            {"type": "float", "value": 1.0, "readonly": False, "doc": None},
-        ],
-        "readonly": False,
-    },
-}
-
-
-# Tests for extract_dict_or_list_entry
-def test_extract_dict_with_valid_list_index() -> None:
-    result = extract_dict_or_list_entry(data_sample, "list_attr[1]")
-    assert result == {"type": "float", "value": 1.0, "readonly": False, "doc": None}
-
-
-def test_extract_dict_without_list_index() -> None:
-    result = extract_dict_or_list_entry(data_sample, "attr1")
-    assert result == {"type": "bool", "value": False, "readonly": False, "doc": None}
-
-
-def test_extract_dict_with_invalid_key() -> None:
-    result = extract_dict_or_list_entry(data_sample, "attr_not_exist")
-    assert result is None
-
-
-def test_extract_dict_with_invalid_list_index() -> None:
-    result = extract_dict_or_list_entry(data_sample, "list_attr[5]")
-    assert result is None
-
-
-# Tests for get_nested_value_from_DataService_by_path_and_key
-def test_get_nested_value_with_default_key() -> None:
-    result = get_nested_value_from_DataService_by_path_and_key(
-        data_sample, "list_attr[0]"
-    )
-    assert result == 0
-
-
-def test_get_nested_value_with_custom_key() -> None:
-    result = get_nested_value_from_DataService_by_path_and_key(
-        data_sample, "class_attr.sub_attr", "type"
-    )
-    assert result == "float"
-
-
-def test_get_nested_value_with_invalid_path() -> None:
-    result = get_nested_value_from_DataService_by_path_and_key(
-        data_sample, "class_attr.nonexistent_attr"
-    )
-    assert result is None
+from pydase.utils.helpers import is_property_attribute
 
 
 @pytest.mark.parametrize(

tests/utils/test_logging.py

@@ -0,0 +1,71 @@
+import logging
+
+from pytest import LogCaptureFixture
+
+from pydase.utils.logging import setup_logging
+
+
+def test_log_error(caplog: LogCaptureFixture):
+    setup_logging("ERROR")
+    logger = logging.getLogger()
+    logger.debug("This is a debug message")
+    logger.info("This is an info message")
+    logger.warning("This is a warning message")
+    logger.error("This is an error message")
+
+    # Check the log records as well as the level.
+    assert "This is a debug message" not in caplog.text
+    assert "This is an info message" not in caplog.text
+    assert "This is a warning message" not in caplog.text
+    assert "This is an error message" in caplog.text
+    assert any(record.levelname == "ERROR" for record in caplog.records)
+
+
+def test_log_warning(caplog: LogCaptureFixture):
+    setup_logging("WARNING")
+    logger = logging.getLogger()
+    logger.debug("This is a debug message")
+    logger.info("This is an info message")
+    logger.warning("This is a warning message")
+    logger.error("This is an error message")
+
+    # Check the log records as well as the level.
+    assert "This is a debug message" not in caplog.text
+    assert "This is an info message" not in caplog.text
+    assert "This is a warning message" in caplog.text
+    assert "This is an error message" in caplog.text
+    assert any(record.levelname == "ERROR" for record in caplog.records)
+
+
+def test_log_debug(caplog: LogCaptureFixture):
+    setup_logging("DEBUG")
+    logger = (
+        logging.getLogger()
+    )  # Get the root logger or replace with the appropriate logger.
+    logger.debug("This is a debug message")
+    logger.info("This is an info message")
+    logger.warning("This is a warning message")
+    logger.error("This is an error message")
+
+    # Now, check that the message is in the log records.
+    assert "This is a debug message" in caplog.text
+    assert "This is an info message" in caplog.text
+    assert "This is a warning message" in caplog.text
+    assert "This is an error message" in caplog.text
+
+
+def test_log_info(caplog: LogCaptureFixture):
+    setup_logging("INFO")
+    logger = (
+        logging.getLogger()
+    )  # Get the root logger or replace with the appropriate logger.
+    logger.debug("This is a debug message")
+    logger.info("This is an info message")
+    logger.warning("This is a warning message")
+    logger.error("This is an error message")
+
+    # Now, check that the message is in the log records.
+    assert "This is a debug message" not in caplog.text
+    assert "This is an info message" in caplog.text
+    assert "This is a warning message" in caplog.text
+    assert "This is an error message" in caplog.text

tests/utils/test_serializer.py

@@ -0,0 +1,417 @@
+import asyncio
+from enum import Enum
+
+import pytest
+
+import pydase
+import pydase.units as u
+from pydase.components.coloured_enum import ColouredEnum
+from pydase.utils.serializer import (
+    SerializationPathError,
+    dump,
+    get_nested_dict_by_path,
+    get_next_level_dict_by_key,
+    set_nested_value_by_path,
+)
+
+
+@pytest.mark.parametrize(
+    "test_input, expected",
+    [
+        (1, {"type": "int", "value": 1, "readonly": False, "doc": None}),
+        (1.0, {"type": "float", "value": 1.0, "readonly": False, "doc": None}),
+        (True, {"type": "bool", "value": True, "readonly": False, "doc": None}),
+        (
+            u.Quantity(10, "m"),
+            {
+                "type": "Quantity",
+                "value": {"magnitude": 10, "unit": "meter"},
+                "readonly": False,
+                "doc": None,
+            },
+        ),
+    ],
+)
+def test_dump(test_input, expected):
+    assert dump(test_input) == expected
+
+
+def test_enum_serialize() -> None:
+    class EnumClass(Enum):
+        FOO = "foo"
+        BAR = "bar"
+
+    class EnumAttribute(pydase.DataService):
+        def __init__(self) -> None:
+            self.some_enum = EnumClass.FOO
+            super().__init__()
+
+    class EnumPropertyWithoutSetter(pydase.DataService):
+        def __init__(self) -> None:
+            self._some_enum = EnumClass.FOO
+            super().__init__()
+
+        @property
+        def some_enum(self) -> EnumClass:
+            return self._some_enum
+
+    class EnumPropertyWithSetter(pydase.DataService):
+        def __init__(self) -> None:
+            self._some_enum = EnumClass.FOO
+            super().__init__()
+
+        @property
+        def some_enum(self) -> EnumClass:
+            return self._some_enum
+
+        @some_enum.setter
+        def some_enum(self, value: EnumClass) -> None:
+            self._some_enum = value
+
+    assert dump(EnumAttribute())["value"] == {
+        "some_enum": {
+            "type": "Enum",
+            "value": "FOO",
+            "enum": {"FOO": "foo", "BAR": "bar"},
+            "readonly": False,
+            "doc": None,
+        }
+    }
+    assert dump(EnumPropertyWithoutSetter())["value"] == {
+        "some_enum": {
+            "type": "Enum",
+            "value": "FOO",
+            "enum": {"FOO": "foo", "BAR": "bar"},
+            "readonly": True,
+            "doc": None,
+        }
+    }
+    assert dump(EnumPropertyWithSetter())["value"] == {
+        "some_enum": {
+            "type": "Enum",
+            "value": "FOO",
+            "enum": {"FOO": "foo", "BAR": "bar"},
+            "readonly": False,
+            "doc": None,
+        }
+    }
+
+
+def test_ColouredEnum_serialize() -> None:
+    class Status(ColouredEnum):
+        PENDING = "#FFA500"
+        RUNNING = "#0000FF80"
+        PAUSED = "rgb(169, 169, 169)"
+        RETRYING = "rgba(255, 255, 0, 0.3)"
+        COMPLETED = "hsl(120, 100%, 50%)"
+        FAILED = "hsla(0, 100%, 50%, 0.7)"
+        CANCELLED = "SlateGray"
+
+    assert dump(Status.FAILED) == {
+        "type": "ColouredEnum",
+        "value": "FAILED",
+        "enum": {
+            "CANCELLED": "SlateGray",
+            "COMPLETED": "hsl(120, 100%, 50%)",
+            "FAILED": "hsla(0, 100%, 50%, 0.7)",
+            "PAUSED": "rgb(169, 169, 169)",
+            "PENDING": "#FFA500",
+            "RETRYING": "rgba(255, 255, 0, 0.3)",
+            "RUNNING": "#0000FF80",
+        },
+        "readonly": False,
+        "doc": None,
+    }
+
+
+def test_method_serialization() -> None:
+    class ClassWithMethod(pydase.DataService):
+        def some_method(self) -> str:
+            return "some method"
+
+        async def some_task(self, sleep_time: int) -> None:
+            while True:
+                await asyncio.sleep(sleep_time)
+
+    instance = ClassWithMethod()
+    instance.start_some_task(10)  # type: ignore
+
+    assert dump(instance)["value"] == {
+        "some_method": {
+            "async": False,
+            "doc": None,
+            "parameters": {},
+            "readonly": True,
+            "type": "method",
+            "value": None,
+        },
+        "some_task": {
+            "async": True,
+            "doc": None,
+            "parameters": {"sleep_time": "int"},
+            "readonly": True,
+            "type": "method",
+            "value": {"sleep_time": 10},
+        },
+    }
+
+
+def test_methods_with_type_hints() -> None:
+    def method_without_type_hint(arg_without_type_hint) -> None:
+        pass
+
+    def method_with_type_hint(some_argument: int) -> None:
+        pass
+
+    def method_with_union_type_hint(some_argument: int | float) -> None:
+        pass
+
+    assert dump(method_without_type_hint) == {
+        "async": False,
+        "doc": None,
+        "parameters": {"arg_without_type_hint": None},
+        "readonly": True,
+        "type": "method",
+        "value": None,
+    }
+
+    assert dump(method_with_type_hint) == {
+        "async": False,
+        "doc": None,
+        "parameters": {"some_argument": "int"},
+        "readonly": True,
+        "type": "method",
+        "value": None,
+    }
+
+    assert dump(method_with_union_type_hint) == {
+        "async": False,
+        "doc": None,
+        "parameters": {"some_argument": "int | float"},
+        "readonly": True,
+        "type": "method",
+        "value": None,
+    }
+
+
+def test_list_serialization() -> None:
+    class MySubclass(pydase.DataService):
+        _name = "hi"
+        bool_attr = True
+        int_attr = 1
+
+        @property
+        def name(self) -> str:
+            return self._name
+
+    class ClassWithListAttribute(pydase.DataService):
+        list_attr = [1, MySubclass()]
+
+    instance = ClassWithListAttribute()
+
+    assert dump(instance)["value"] == {
+        "list_attr": {
+            "doc": None,
+            "readonly": False,
+            "type": "list",
+            "value": [
+                {"doc": None, "readonly": False, "type": "int", "value": 1},
+                {
+                    "doc": None,
+                    "readonly": False,
+                    "type": "DataService",
+                    "value": {
+                        "bool_attr": {
+                            "doc": None,
+                            "readonly": False,
+                            "type": "bool",
+                            "value": True,
+                        },
+                        "int_attr": {
+                            "doc": None,
+                            "readonly": False,
+                            "type": "int",
+                            "value": 1,
+                        },
+                        "name": {
+                            "doc": None,
+                            "readonly": True,
+                            "type": "str",
+                            "value": "hi",
+                        },
+                    },
+                },
+            ],
+        }
+    }
+
+
+def test_dict_serialization() -> None:
+    class MyClass(pydase.DataService):
+        name = "my class"
+
+    test_dict = {
+        "int_key": 1,
+        "float_key": 1.0,
+        "bool_key": True,
+        "Quantity_key": 1.0 * u.units.s,
+        "DataService_key": MyClass(),
+    }
+
+    assert dump(test_dict) == {
+        "doc": None,
+        "readonly": False,
+        "type": "dict",
+        "value": {
+            "DataService_key": {
+                "doc": None,
+                "readonly": False,
+                "type": "DataService",
+                "value": {
+                    "name": {
+                        "doc": None,
+                        "readonly": False,
+                        "type": "str",
+                        "value": "my class",
+                    }
+                },
+            },
+            "Quantity_key": {
+                "doc": None,
+                "readonly": False,
+                "type": "Quantity",
+                "value": {"magnitude": 1.0, "unit": "s"},
+            },
+            "bool_key": {"doc": None, "readonly": False, "type": "bool", "value": True},
+            "float_key": {
+                "doc": None,
+                "readonly": False,
+                "type": "float",
+                "value": 1.0,
+            },
+            "int_key": {"doc": None, "readonly": False, "type": "int", "value": 1},
+        },
+    }
+
+
+@pytest.fixture
+def setup_dict():
+    class MySubclass(pydase.DataService):
+        attr3 = 1.0
+        list_attr = [1.0, 1]
+
+    class ServiceClass(pydase.DataService):
+        attr1 = 1.0
+        attr2 = MySubclass()
+        attr_list = [0, 1, MySubclass()]
+
+    return ServiceClass().serialize()
+
+
+def test_update_attribute(setup_dict):
+    set_nested_value_by_path(setup_dict, "attr1", 15)
+    assert setup_dict["attr1"]["value"] == 15
+
+
+def test_update_nested_attribute(setup_dict):
+    set_nested_value_by_path(setup_dict, "attr2.attr3", 25.0)
+    assert setup_dict["attr2"]["value"]["attr3"]["value"] == 25.0
+
+
+def test_update_list_entry(setup_dict):
+    set_nested_value_by_path(setup_dict, "attr_list[1]", 20)
+    assert setup_dict["attr_list"]["value"][1]["value"] == 20
+
+
+def test_update_list_append(setup_dict):
+    set_nested_value_by_path(setup_dict, "attr_list[3]", 20)
+    assert setup_dict["attr_list"]["value"][3]["value"] == 20
+
+
+def test_update_invalid_list_index(setup_dict, caplog: pytest.LogCaptureFixture):
+    set_nested_value_by_path(setup_dict, "attr_list[10]", 30)
+    assert (
+        "Error occured trying to change 'attr_list[10]': list index "
+        "out of range" in caplog.text
+    )
+
+
+def test_update_invalid_path(setup_dict, caplog: pytest.LogCaptureFixture):
+    set_nested_value_by_path(setup_dict, "invalid_path", 30)
+    assert (
+        "Error occured trying to access the key 'invalid_path': it is either "
+        "not present in the current dictionary or its value does not contain "
+        "a 'value' key." in caplog.text
+    )
+
+
+def test_update_list_inside_class(setup_dict):
+    set_nested_value_by_path(setup_dict, "attr2.list_attr[1]", 40)
+    assert setup_dict["attr2"]["value"]["list_attr"]["value"][1]["value"] == 40
+
+
+def test_update_class_attribute_inside_list(setup_dict):
+    set_nested_value_by_path(setup_dict, "attr_list[2].attr3", 50)
+    assert setup_dict["attr_list"]["value"][2]["value"]["attr3"]["value"] == 50
+
+
+def test_get_next_level_attribute_nested_dict(setup_dict):
+    nested_dict = get_next_level_dict_by_key(setup_dict, "attr1")
+    assert nested_dict == setup_dict["attr1"]
+
+
+def test_get_next_level_list_entry_nested_dict(setup_dict):
+    nested_dict = get_next_level_dict_by_key(setup_dict, "attr_list[0]")
+    assert nested_dict == setup_dict["attr_list"]["value"][0]
+
+
+def test_get_next_level_invalid_path_nested_dict(setup_dict):
+    with pytest.raises(SerializationPathError):
+        get_next_level_dict_by_key(setup_dict, "invalid_path")
+
+
+def test_get_next_level_invalid_list_index(setup_dict):
+    with pytest.raises(SerializationPathError):
+        get_next_level_dict_by_key(setup_dict, "attr_list[10]")
+
+
+def test_get_attribute(setup_dict):
+    nested_dict = get_nested_dict_by_path(setup_dict, "attr1")
+    assert nested_dict["value"] == 1.0
+
+
+def test_get_nested_attribute(setup_dict):
+    nested_dict = get_nested_dict_by_path(setup_dict, "attr2.attr3")
+    assert nested_dict["value"] == 1.0
+
+
+def test_get_list_entry(setup_dict):
+    nested_dict = get_nested_dict_by_path(setup_dict, "attr_list[1]")
+    assert nested_dict["value"] == 1
+
+
+def test_get_list_inside_class(setup_dict):
+    nested_dict = get_nested_dict_by_path(setup_dict, "attr2.list_attr[1]")
+    assert nested_dict["value"] == 1.0
+
+
+def test_get_class_attribute_inside_list(setup_dict):
+    nested_dict = get_nested_dict_by_path(setup_dict, "attr_list[2].attr3")
+    assert nested_dict["value"] == 1.0
+
+
+def test_get_invalid_list_index(setup_dict, caplog: pytest.LogCaptureFixture):
+    get_nested_dict_by_path(setup_dict, "attr_list[10]")
+    assert (
+        "Error occured trying to change 'attr_list[10]': list index "
+        "out of range" in caplog.text
+    )
+
+
+def test_get_invalid_path(setup_dict, caplog: pytest.LogCaptureFixture):
+    get_nested_dict_by_path(setup_dict, "invalid_path")
+    assert (
+        "Error occured trying to access the key 'invalid_path': it is either "
+        "not present in the current dictionary or its value does not contain "
+        "a 'value' key." in caplog.text
+    )

tests/utils/test_warnings.py

@@ -2,8 +2,6 @@ from pytest import LogCaptureFixture
 
 from pydase import DataService
 
-from . import caplog  # noqa
-
 
 def test_setattr_warnings(caplog: LogCaptureFixture) -> None:  # noqa
     # def test_setattr_warnings(capsys: CaptureFixture) -> None:
@@ -32,3 +30,19 @@ def test_private_attribute_warning(caplog: LogCaptureFixture) -> None:  # noqa
         " Warning: You should not set private but rather protected attributes! Use "
         "_something instead of __something." in caplog.text
     )
+
+
+def test_protected_attribute_warning(caplog: LogCaptureFixture) -> None:  # noqa
+    class SubClass:
+        name = "Hello"
+
+    class ServiceClass(DataService):
+        def __init__(self) -> None:
+            self._subclass = SubClass
+            super().__init__()
+
+    ServiceClass()
+
+    assert (
+        "Warning: Class SubClass does not inherit from DataService." not in caplog.text
+    )