Structured Logging Fundamentals
Convert a Node.js API's console.log calls to structured JSON logging with Pino, attach request-scoped context with child loggers, redact sensitive fields, and prepare your logs to correlate with distributed traces later in this roadmap.
Every Node.js project starts with console.log("got here"). It works fine on one laptop with one request at a time. It stops working the moment you have more than one service, more than one instance of that service, or more than one concurrent request — because plain-text lines carry no machine-readable structure, so you can't filter by user, by request, or by severity without writing fragile regex.
In this project you'll take a small Express API and convert its logging to structured JSON using Pino, currently the fastest widely-used Node.js logging library (its own benchmarks show it consistently outperforming Winston and Bunyan). By the end, every log line will be a JSON object with a level, a timestamp, and contextual fields you can query.
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