app/core/logging.py

import json
import logging
from datetime import datetime
from typing import Any

from app.core.config import get_settings


class JsonFormatter(logging.Formatter):
    def format(self, record: logging.LogRecord) -> str:
        log_entry: dict[str, Any] = {
            "timestamp": datetime.fromtimestamp(record.created).isoformat() + "Z",
            "level": record.levelname,
            "module": record.module,
            "message": record.getMessage(),
        }

        # Add extra fields if they exist, ignoring some standard ones
        extra: dict[str, Any] = {}
        for key, value in record.__dict__.items():
            if key not in [
                "args",
                "asctime",
                "created",
                "exc_info",
                "exc_text",
                "filename",
                "funcName",
                "id",
                "levelname",
                "levelno",
                "lineno",
                "module",
                "msecs",
                "message",
                "msg",
                "name",
                "pathname",
                "process",
                "processName",
                "relativeCreated",
                "stack_info",
                "thread",
                "threadName",
            ]:
                extra[key] = value

        if extra:
            log_entry["extra"] = extra
        
        if record.exc_info:
            log_entry["exc_info"] = self.formatException(record.exc_info)

        return json.dumps(log_entry)


def get_logger(name: str) -> logging.Logger:
    settings = get_settings()
    logger = logging.getLogger(name)
    
    # Avoid adding duplicate handlers
    if not logger.handlers:
        logger.setLevel(settings.LOG_LEVEL.upper())
        handler = logging.StreamHandler()
        handler.setFormatter(JsonFormatter())
        logger.addHandler(handler)
        
        # Don't propagate to the root logger to avoid duplicate log lines
        logger.propagate = False
        
    return logger