src/logger.py

"""
logger.py — Structured logging using structlog.

Outputs pretty console logs in development, JSON in production.
"""

import logging
import sys

import structlog

from src.config import settings


def configure_logging() -> None:
    """Configure structlog based on app environment."""
    shared_processors = [
        structlog.contextvars.merge_contextvars,
        structlog.stdlib.add_logger_name,
        structlog.stdlib.add_log_level,
        structlog.processors.TimeStamper(fmt="iso"),
        structlog.processors.StackInfoRenderer(),
    ]

    if settings.log_format == "json" or settings.is_production:
        renderer = structlog.processors.JSONRenderer()
    else:
        renderer = structlog.dev.ConsoleRenderer(colors=True)  # type: ignore[assignment]

    structlog.configure(
        processors=[
            *shared_processors,
            structlog.stdlib.ProcessorFormatter.wrap_for_formatter,
        ],
        wrapper_class=structlog.stdlib.BoundLogger,
        context_class=dict,
        logger_factory=structlog.stdlib.LoggerFactory(),
        cache_logger_on_first_use=True,
    )

    formatter = structlog.stdlib.ProcessorFormatter(
        processor=renderer,
        foreign_pre_chain=shared_processors,
    )
    handler = logging.StreamHandler(sys.stdout)
    handler.setFormatter(formatter)

    root_logger = logging.getLogger()
    root_logger.handlers = [handler]
    root_logger.setLevel(settings.log_level)


def get_logger(name: str) -> structlog.stdlib.BoundLogger:
    configure_logging()
    return structlog.get_logger(name)