Module Overview

What You’ll Learn

• Explain why console.log isn’t sufficient logging for a production application
• Add structured logging to an Express app
• Distinguish operational errors from programmer errors, and log each appropriately

💡 Why this matters: Node.js & Express Foundations covered catching errors correctly. This module covers what happens after they’re caught, whether anyone actually finds out, and can tell a harmless 404 apart from a real, actionable failure.

What’s Covered

• Why console.log isn’t enough, no levels, no structure, nothing searchable in production.
• Structured logging, log levels, and consistent, parseable log output.
• Logging in middleware, tying logs to the request that caused them.
• Operational versus programmer errors, a distinction from Node.js & Express Foundations, revisited here for what it means for logging and monitoring specifically.

Hands-On

By the end of this module, you’ll have structured, leveled logging wired into an Express app’s error handler, distinguishing routine client errors from real, unexpected failures.

This is the final module before the course capstone, a complete, authenticated, validated, tested, and hardened API.