Simplify logging. Allow to passing handlers to entrypoint

[mosquito]

Summary

This PR introduces significant improvements to the logging system while also applying several style reformatting changes (referred to as “reformat with gray”) across the codebase.

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Major Changes: Logging System Enhancements

• New ThreadedHandler:

  • Introduces a dedicated logging handler that processes log records on a separate thread using an internal queue.
  • Improves asynchronous logging by offloading log processing from the event loop.

• Deprecation of Legacy MemoryHandler Approach:

  • The previous mechanism (using logging.handlers.MemoryHandler and a background flusher) is replaced.
  • wrap_logging_handler now issues a deprecation warning and returns an instance of the new ThreadedHandler.

• Updated Logging Configuration in basic_config:

  • User-provided handlers are now wrapped with ThreadedHandler, ensuring:
    • Proper asynchronous handling.
    • Integration with the unhandled exception hook.
    • Graceful shutdown via dedicated thread termination.

• Additional Logging Adjustments:

  • Refined exception logging in UnhandledLoopHook for better trace formatting.
  • Exported the new ThreadedHandler in the public API to allow custom usage if needed.

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Other Changes: Reformat with Gray

• Function Signatures and Imports:

  • Added trailing commas to multi-line parameter lists for consistency.
  • Consolidated and reformatted import statements in several modules (e.g., aggregate.py, backoff.py, entrypoint.py, uvicorn.py, and timeout.py).

• Minor Code Cleanups:

  • Updated syntax and formatting details to improve overall readability.
  • These changes are purely cosmetic and do not impact functionality.

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Motivation

• Enhanced Asynchronous Logging:
  By offloading logging to a separate thread, the new system minimizes the risk of blocking the asyncio event loop, especially under high load.

• Improved Code Consistency:
  The reformatting changes (reformat with gray) make the codebase cleaner and more maintainable without altering any business logic.

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Impact

• The logging improvements are transparent for most users, aside from receiving a deprecation warning if using the old wrap_logging_handler.
• The reformatting changes have no functional impact and only serve to standardize the code style.

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Migration

• For Users:

  • No immediate changes are required. However, users with custom logging configurations should be aware of the deprecation of the old memory handler mechanism.
  • It is recommended to transition to the new logging system to benefit from the improved performance and reliability.

• Documentation:

  • Update any custom documentation or configuration guides to reflect the changes in logging setup and usage of ThreadedHandler.

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Feedback and suggestions are welcome. This refactor sets a robust foundation for asynchronous logging while ensuring the code remains clean and consistent through the reformatting updates.