feat: adds logging setup

- logging can now be configured using the setup_logging function and
  using the ENVIRONMENT env variable.
- using InterceptHandler to intercept standard logging towards the
  loguru sink
- forcing uvicorn to use the same handler

src/pydase/__init__.py

@@ -1,5 +1,8 @@
 from pydase.data_service import DataService
 from pydase.server import Server
+from pydase.utils.logging import setup_logging
+
+setup_logging()
 
 __all__ = [
     "DataService",

src/pydase/utils/logging.py

@@ -0,0 +1,78 @@
+import logging
+import sys
+from types import FrameType
+from typing import Optional
+
+import loguru
+from uvicorn.config import LOGGING_CONFIG
+
+import pydase.config
+
+ALLOWED_LOG_LEVELS = ["DEBUG", "INFO", "ERROR"]
+
+
+# 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
+
+        # Get corresponding Loguru level if it exists.
+        level: int | str
+        try:
+            level = loguru.logger.level(record.levelname).name
+        except ValueError:
+            level = record.levelno
+
+        # 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
+
+        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
+
+        loguru.logger.opt(depth=depth, exception=record.exc_info).log(level, msg)
+
+
+def setup_logging(level: Optional[str] = None) -> None:
+    loguru.logger.debug("Configuring service logging.")
+
+    if pydase.config.OperationMode().environment == "development":
+        log_level = "DEBUG"
+    else:
+        log_level = "INFO"
+
+    if level is not None and level in ALLOWED_LOG_LEVELS:
+        log_level = level
+
+    loguru.logger.remove()
+    loguru.logger.add(sys.stderr, level=log_level)
+
+    logging.basicConfig(handlers=[InterceptHandler()], level=0, force=True)
+    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",
+        },
+    }