utils/logger.py

"""
Logger Configuration Module

This module configures structured logging for the API Comparator service using structlog.
It provides customized log formatting with source file information and exception handling.
"""

import logging
import re
from typing import Dict, Any

import structlog


def custom_processor(_, __, event_dict: Dict[str, Any]) -> Dict[str, Any]:
    """Process log events to add source file information and handle exceptions.
    
    Args:
        _: Unused logger parameter
        __: Unused name parameter
        event_dict: The log event dictionary to process
        
    Returns:
        Dict[str, Any]: The processed log event dictionary with added source information
    """
    event_dict["source"] = f"{event_dict.pop('filename')}:{event_dict.pop('lineno')}"
    if event_dict.get("level") == "error" and "exception" in event_dict:
        exception_info = event_dict.pop("exception")
        match = re.search(r'File \".*?\", line (\d+)', exception_info)
        if match:
            event_dict["source"] = f"{event_dict['source'].split(':')[0]}:{match.group(1)}"
    return event_dict

# Configure structlog
structlog.configure(
    processors=[
        structlog.processors.TimeStamper(fmt="iso"),
        structlog.processors.add_log_level,
        structlog.processors.StackInfoRenderer(),
        structlog.processors.format_exc_info,
        structlog.processors.CallsiteParameterAdder(
            [structlog.processors.CallsiteParameter.FILENAME, 
             structlog.processors.CallsiteParameter.LINENO]
        ),
        custom_processor,
        structlog.processors.JSONRenderer(),
    ],
    wrapper_class=structlog.make_filtering_bound_logger(logging.INFO),
    context_class=dict,
    logger_factory=structlog.PrintLoggerFactory(),
    cache_logger_on_first_use=True,
)