feat: creating CallbackManager class which does all the callback related stuff

This commit is contained in:
Mose Müller 2023-08-02 12:06:22 +02:00
parent 2e683df6ef
commit 4265929b4e
2 changed files with 190 additions and 177 deletions

View File

@ -37,7 +37,7 @@ def process_callable_attribute(attr: Any, args: dict[str, Any]) -> Any:
)
class DataService(rpyc.Service, TaskManager):
class CallbackManager:
_list_mapping: dict[int, DataServiceList] = {}
"""
A dictionary mapping the id of the original lists to the corresponding
@ -47,135 +47,10 @@ class DataService(rpyc.Service, TaskManager):
be tracked consistently. The keys of the dictionary are the ids of the original
lists, and the values are the DataServiceList instances that wrap these lists.
"""
_notification_callbacks: list[Callable[[str, str, Any], Any]] = []
"""
A list of callback functions that are executed when a change occurs in the
DataService instance. These functions are intended to handle or respond to these
changes in some way, such as emitting a socket.io message to the frontend.
Each function in this list should be a callable that accepts three parameters:
- parent_path (str): The path to the parent of the attribute that was changed.
- name (str): The name of the attribute that was changed.
- value (Any): The new value of the attribute.
A callback function can be added to this list using the add_notification_callback
method. Whenever a change in the DataService instance occurs (or in its nested
DataService or DataServiceList instances), the _emit_notification method is invoked,
which in turn calls all the callback functions in _notification_callbacks with the
appropriate arguments.
This implementation follows the observer pattern, with the DataService instance as
the "subject" and the callback functions as the "observers".
"""
def __init__(self, filename: Optional[str] = None) -> None:
TaskManager.__init__(self)
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."""
self._callbacks: set[Callable[[str, Any], None]] = set()
self._filename: Optional[str] = filename
self._register_callbacks()
self.__check_instance_classes()
self._initialised = True
self._load_values_from_json()
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.
"""
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"...'
)
def load_DataService_from_JSON(self, json_dict: dict[str, Any]) -> None:
# 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_by_path_and_key(json_dict, path=path)
value_type = get_nested_value_by_path_and_key(
json_dict, path=path, key="type"
)
class_value_type = get_nested_value_by_path_and_key(
serialized_class, path=path, key="type"
)
if class_value_type == value_type:
# Split the path into parts
parts = path.split(".")
attr_name = parts[-1]
self.update_DataService_attribute(parts[:-1], attr_name, value)
else:
logger.info(
f'Attribute type of "{path}" changed from "{value_type}" to '
f'"{class_value_type}". Ignoring value from JSON file...'
)
def __setattr__(self, __name: str, __value: Any) -> None:
current_value = getattr(self, __name, None)
# parse ints into floats if current value is a float
if isinstance(current_value, float) and isinstance(__value, int):
__value = float(__value)
super().__setattr__(__name, __value)
if self.__dict__.get("_initialised") and not __name == "_initialised":
for callback in self._callbacks:
callback(__name, __value)
elif __name.startswith(f"_{self.__class__.__name__}__"):
logger.warning(
f"Warning: You should not set private but rather protected attributes! "
f"Use {__name.replace(f'_{self.__class__.__name__}__', '_')} instead "
f"of {__name.replace(f'_{self.__class__.__name__}__', '__')}."
)
def _rpyc_getattr(self, name: str) -> Any:
if name.startswith("_"):
# disallow special and private attributes
raise AttributeError("cannot access private/special names")
# allow all other attributes
return getattr(self, name)
def _rpyc_setattr(self, name: str, value: Any) -> None:
if name.startswith("_"):
# disallow special and private attributes
raise AttributeError("cannot access private/special names")
# check if the attribute has a setter method
attr = getattr(self, name, None)
if isinstance(attr, property) and attr.fset is None:
raise AttributeError(f"{name} attribute does not have a setter method")
# allow all other attributes
setattr(self, name, value)
def _register_callbacks(self) -> None:
self._register_list_change_callbacks(self, f"{self.__class__.__name__}")
self._register_DataService_instance_callbacks(
self, f"{self.__class__.__name__}"
)
self._register_property_callbacks(self, f"{self.__class__.__name__}")
self._register_start_stop_task_callbacks(self, f"{self.__class__.__name__}")
def __init__(self, service: "DataService") -> None:
self.callbacks: set[Callable[[str, Any], None]] = set()
self.service = service
def _register_list_change_callbacks( # noqa: C901
self, obj: "DataService", parent_path: str
@ -221,12 +96,12 @@ class DataService(rpyc.Service, TaskManager):
# value at the time the lambda is defined, not when it is called. This
# prevents attr_name from being overwritten in the next loop iteration.
callback = (
lambda index, value, attr_name=attr_name: self._emit_notification(
lambda index, value, attr_name=attr_name: self.service._emit_notification(
parent_path=parent_path,
name=f"{attr_name}[{index}]",
value=value,
)
if self == self.__root__
if self.service == self.service.__root__
else None
)
@ -285,7 +160,7 @@ class DataService(rpyc.Service, TaskManager):
lambda name, value: obj._emit_notification(
parent_path=parent_path, name=name, value=value
)
if self == obj.__root__
if self.service == obj.__root__
and not name.startswith("_") # we are only interested in public attributes
and not isinstance(
getattr(type(obj), name, None), property
@ -293,7 +168,7 @@ class DataService(rpyc.Service, TaskManager):
else None
)
obj._callbacks.add(callback)
obj._callback_manager.callbacks.add(callback)
# Recursively register callbacks for all nested attributes of the object
attrs = get_class_and_instance_attributes(obj)
@ -325,7 +200,7 @@ class DataService(rpyc.Service, TaskManager):
# as the DataService is an attribute of self, change the root object
# use the dictionary to not trigger callbacks on initialised objects
nested_attr.__dict__["__root__"] = self.__root__
nested_attr.__dict__["__root__"] = self.service.__root__
new_path = f"{parent_path}.{attr_name}"
self._register_DataService_instance_callbacks(nested_attr, new_path)
@ -356,7 +231,7 @@ class DataService(rpyc.Service, TaskManager):
# changed, not reassigned)
for item in obj_list:
if isinstance(item, DataService):
item._callbacks.add(callback)
item._callback_manager.callbacks.add(callback)
for attr_name in set(dir(item)) - set(dir(object)) - {"__root__"}:
attr_value = getattr(item, attr_name)
if isinstance(attr_value, (DataService, DataServiceList)):
@ -421,7 +296,7 @@ class DataService(rpyc.Service, TaskManager):
name=dependent_attr,
value=getattr(obj, dependent_attr),
)
if self == obj.__root__
if self.service == obj.__root__
else None
)
@ -436,11 +311,188 @@ class DataService(rpyc.Service, TaskManager):
name=dependent_attr,
value=getattr(obj, dependent_attr),
)
if name == dep and self == obj.__root__
if name == dep and self.service == obj.__root__
else None
)
# Add to _callbacks
obj._callbacks.add(callback)
obj._callback_manager.callbacks.add(callback)
def _register_start_stop_task_callbacks(
self, obj: "DataService", parent_path: str
) -> None:
"""
This function registers callbacks for start and stop methods of async functions.
These callbacks are stored in the '_task_status_change_callbacks' attribute and
are called when the status of a task changes.
Parameters:
-----------
obj: DataService
The target object on which callbacks are to be registered.
parent_path: str
The access path for the parent object. This is used to construct the full
access path for the notifications.
"""
# Create and register a callback for the object
# only emit the notification when the call was registered by the root object
callback: Callable[[str, dict[str, Any] | None], None] = (
lambda name, status: obj._emit_notification(
parent_path=parent_path, name=name, value=status
)
if self.service == obj.__root__
and not name.startswith("_") # we are only interested in public attributes
else None
)
obj._task_status_change_callbacks.append(callback)
# Recursively register callbacks for all nested attributes of the object
attrs: dict[str, Any] = get_class_and_instance_attributes(obj)
for nested_attr_name, nested_attr in attrs.items():
if isinstance(nested_attr, DataService):
self._register_start_stop_task_callbacks(
nested_attr, parent_path=f"{parent_path}.{nested_attr_name}"
)
def register_callbacks(self) -> None:
self._register_list_change_callbacks(
self.service, f"{self.service.__class__.__name__}"
)
self._register_DataService_instance_callbacks(
self.service, f"{self.service.__class__.__name__}"
)
self._register_property_callbacks(
self.service, f"{self.service.__class__.__name__}"
)
self._register_start_stop_task_callbacks(
self.service, f"{self.service.__class__.__name__}"
)
class DataService(rpyc.Service, TaskManager):
_notification_callbacks: list[Callable[[str, str, Any], Any]] = []
"""
A list of callback functions that are executed when a change occurs in the
DataService instance. These functions are intended to handle or respond to these
changes in some way, such as emitting a socket.io message to the frontend.
Each function in this list should be a callable that accepts three parameters:
- parent_path (str): The path to the parent of the attribute that was changed.
- name (str): The name of the attribute that was changed.
- value (Any): The new value of the attribute.
A callback function can be added to this list using the add_notification_callback
method. Whenever a change in the DataService instance occurs (or in its nested
DataService or DataServiceList instances), the _emit_notification method is invoked,
which in turn calls all the callback functions in _notification_callbacks with the
appropriate arguments.
This implementation follows the observer pattern, with the DataService instance as
the "subject" and the callback functions as the "observers".
"""
def __init__(self, filename: Optional[str] = None) -> None:
TaskManager.__init__(self)
self._callback_manager = CallbackManager(self)
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."""
self._filename: Optional[str] = filename
self._callback_manager.register_callbacks()
self.__check_instance_classes()
self._initialised = True
self._load_values_from_json()
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.
"""
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"...'
)
def load_DataService_from_JSON(self, json_dict: dict[str, Any]) -> None:
# 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_by_path_and_key(json_dict, path=path)
value_type = get_nested_value_by_path_and_key(
json_dict, path=path, key="type"
)
class_value_type = get_nested_value_by_path_and_key(
serialized_class, path=path, key="type"
)
if class_value_type == value_type:
# Split the path into parts
parts = path.split(".")
attr_name = parts[-1]
self.update_DataService_attribute(parts[:-1], attr_name, value)
else:
logger.info(
f'Attribute type of "{path}" changed from "{value_type}" to '
f'"{class_value_type}". Ignoring value from JSON file...'
)
def __setattr__(self, __name: str, __value: Any) -> None:
current_value = getattr(self, __name, None)
# parse ints into floats if current value is a float
if isinstance(current_value, float) and isinstance(__value, int):
__value = float(__value)
super().__setattr__(__name, __value)
if self.__dict__.get("_initialised") and not __name == "_initialised":
for callback in self._callback_manager.callbacks:
callback(__name, __value)
elif __name.startswith(f"_{self.__class__.__name__}__"):
logger.warning(
f"Warning: You should not set private but rather protected attributes! "
f"Use {__name.replace(f'_{self.__class__.__name__}__', '_')} instead "
f"of {__name.replace(f'_{self.__class__.__name__}__', '__')}."
)
def _rpyc_getattr(self, name: str) -> Any:
if name.startswith("_"):
# disallow special and private attributes
raise AttributeError("cannot access private/special names")
# allow all other attributes
return getattr(self, name)
def _rpyc_setattr(self, name: str, value: Any) -> None:
if name.startswith("_"):
# disallow special and private attributes
raise AttributeError("cannot access private/special names")
# check if the attribute has a setter method
attr = getattr(self, name, None)
if isinstance(attr, property) and attr.fset is None:
raise AttributeError(f"{name} attribute does not have a setter method")
# allow all other attributes
setattr(self, name, value)
def __check_instance_classes(self) -> None:
for attr_name, attr_value in get_class_and_instance_attributes(self).items():

View File

@ -95,45 +95,6 @@ class TaskManager(ABC):
self._set_start_and_stop_for_async_methods()
def _register_start_stop_task_callbacks(
self, obj: "TaskManager", parent_path: str
) -> None:
"""
This function registers callbacks for start and stop methods of async functions.
These callbacks are stored in the '_task_status_change_callbacks' attribute and
are called when the status of a task changes.
Parameters:
-----------
obj: DataService
The target object on which callbacks are to be registered.
parent_path: str
The access path for the parent object. This is used to construct the full
access path for the notifications.
"""
# Create and register a callback for the object
# only emit the notification when the call was registered by the root object
callback: Callable[[str, dict[str, Any] | None], None] = (
lambda name, status: obj._emit_notification(
parent_path=parent_path, name=name, value=status
)
if self == obj.__root__
and not name.startswith("_") # we are only interested in public attributes
else None
)
obj._task_status_change_callbacks.append(callback)
# Recursively register callbacks for all nested attributes of the object
attrs: dict[str, Any] = get_class_and_instance_attributes(obj)
for nested_attr_name, nested_attr in attrs.items():
if isinstance(nested_attr, TaskManager):
self._register_start_stop_task_callbacks(
nested_attr, parent_path=f"{parent_path}.{nested_attr_name}"
)
def _set_start_and_stop_for_async_methods(self) -> None: # noqa: C901
# inspect the methods of the class
for name, method in inspect.getmembers(