Application Logging: Best Practices for Debugging and Monitoring

Good logging is essential for debugging and monitoring applications in production.

Key principles: Use structured logging with JSON format. Include timestamp, level, message, and context. Use appropriate log levels: DEBUG, INFO, WARN, ERROR, FATAL.

Never log sensitive data like passwords, tokens, or personal information. Use correlation IDs to trace requests across services.

Centralized logging with ELK stack or cloud solutions like AWS CloudWatch. Set up alerts on error rate spikes.

Best practice: Write logs to stdout in containers. Let the orchestration platform handle log collection and routing.