thrillwiki_django_no_react/backend/config/settings/logging.py

"""
Logging configuration for thrillwiki project.

This module provides a base logging configuration that can be extended
by environment-specific settings. It supports both console and file
logging with optional JSON formatting for production.

Why python-decouple?
- Already used in base.py for consistency
- Simpler API than django-environ
- Sufficient for our configuration needs
- Better separation of config from code

Log Levels (in order of severity):
- DEBUG: Detailed diagnostic information
- INFO: Confirmation that things are working as expected
- WARNING: Indication of potential problems
- ERROR: Serious problems that prevented function execution
- CRITICAL: Critical errors that may cause application failure
"""

from pathlib import Path
from decouple import config

# =============================================================================
# Log File Configuration
# =============================================================================
# Base directory for log files - defaults to logs/ in the backend directory

LOG_DIR = Path(config("LOG_DIR", default="logs"))

# Ensure log directory exists (will be created if not)
LOG_DIR.mkdir(parents=True, exist_ok=True)

# =============================================================================
# Log Formatters
# =============================================================================

LOGGING_FORMATTERS = {
    # Verbose format for development - human readable with full context
    "verbose": {
        "format": "{levelname} {asctime} {module} {process:d} {thread:d} {message}",
        "style": "{",
    },
    # JSON format for production - machine parseable for log aggregation
    "json": {
        "()": "pythonjsonlogger.jsonlogger.JsonFormatter",
        "format": (
            "%(levelname)s %(asctime)s %(module)s %(process)d "
            "%(thread)d %(message)s"
        ),
    },
    # Simple format for console output
    "simple": {
        "format": "{levelname} {message}",
        "style": "{",
    },
    # Request logging format
    "request": {
        "format": "{levelname} {asctime} [{request_id}] {message}",
        "style": "{",
    },
}

# =============================================================================
# Log Handlers
# =============================================================================

LOGGING_HANDLERS = {
    # Console handler - for development and container environments
    "console": {
        "class": "logging.StreamHandler",
        "formatter": "verbose",
        "level": config("CONSOLE_LOG_LEVEL", default="INFO"),
    },
    # Main application log file
    "file": {
        "class": "logging.handlers.RotatingFileHandler",
        "filename": str(LOG_DIR / "thrillwiki.log"),
        "maxBytes": 1024 * 1024 * 10,  # 10MB
        "backupCount": 5,
        "formatter": config("FILE_LOG_FORMATTER", default="json"),
        "level": config("FILE_LOG_LEVEL", default="INFO"),
    },
    # Error-only log file for quick error identification
    "error_file": {
        "class": "logging.handlers.RotatingFileHandler",
        "filename": str(LOG_DIR / "errors.log"),
        "maxBytes": 1024 * 1024 * 15,  # 15MB
        "backupCount": 10,
        "formatter": "json",
        "level": "ERROR",
    },
    # Performance log file for slow queries and performance issues
    "performance": {
        "class": "logging.handlers.RotatingFileHandler",
        "filename": str(LOG_DIR / "performance.log"),
        "maxBytes": 1024 * 1024 * 10,  # 10MB
        "backupCount": 5,
        "formatter": "json",
        "level": "INFO",
    },
    # Security event log file
    "security": {
        "class": "logging.handlers.RotatingFileHandler",
        "filename": str(LOG_DIR / "security.log"),
        "maxBytes": 1024 * 1024 * 10,  # 10MB
        "backupCount": 10,
        "formatter": "json",
        "level": "INFO",
    },
}

# =============================================================================
# Logger Configuration
# =============================================================================

LOGGING_LOGGERS = {
    # Django framework logging
    "django": {
        "handlers": ["console", "file"],
        "level": config("DJANGO_LOG_LEVEL", default="WARNING"),
        "propagate": False,
    },
    # Django database queries - useful for debugging N+1 issues
    "django.db.backends": {
        "handlers": ["console"],
        "level": config("DB_LOG_LEVEL", default="WARNING"),
        "propagate": False,
    },
    # Django request handling
    "django.request": {
        "handlers": ["console", "error_file"],
        "level": "ERROR",
        "propagate": False,
    },
    # Django security events
    "django.security": {
        "handlers": ["console", "security"],
        "level": "WARNING",
        "propagate": False,
    },
    # Application logging
    "thrillwiki": {
        "handlers": ["console", "file"],
        "level": config("APP_LOG_LEVEL", default="INFO"),
        "propagate": False,
    },
    # Performance monitoring
    "performance": {
        "handlers": ["performance"],
        "level": config("PERFORMANCE_LOG_LEVEL", default="INFO"),
        "propagate": False,
    },
    # Query optimization warnings
    "query_optimization": {
        "handlers": ["console", "file"],
        "level": config("QUERY_LOG_LEVEL", default="WARNING"),
        "propagate": False,
    },
    # N+1 query detection
    "nplusone": {
        "handlers": ["console"],
        "level": config("NPLUSONE_LOG_LEVEL", default="WARNING"),
        "propagate": False,
    },
    # Request logging
    "request_logging": {
        "handlers": ["console"],
        "level": config("REQUEST_LOG_LEVEL", default="INFO"),
        "propagate": False,
    },
    # Security events
    "security": {
        "handlers": ["console", "security"],
        "level": "INFO",
        "propagate": False,
    },
    # Celery task logging
    "celery": {
        "handlers": ["console", "file"],
        "level": config("CELERY_LOG_LEVEL", default="INFO"),
        "propagate": False,
    },
}

# =============================================================================
# Complete Logging Configuration
# =============================================================================

LOGGING = {
    "version": 1,
    "disable_existing_loggers": False,
    "formatters": LOGGING_FORMATTERS,
    "handlers": LOGGING_HANDLERS,
    "root": {
        "level": config("ROOT_LOG_LEVEL", default="INFO"),
        "handlers": ["console"],
    },
    "loggers": LOGGING_LOGGERS,
}