Add structured logging with pino and request correlation

[mikewheeleer]

Implement structured logging with pino and request correlation

Description

The timing middleware in src/index.ts emits logs via a hand-rolled console.log(JSON.stringify(...)), gated on NODE_ENV !== "test". There is no log level, no error logging from the error handler, and no consistent field schema. This issue introduces a pino logger with the requestId as a correlation field and structured error logs.

Requirements and context

• Repository scope: StableRoute-Org/Stableroute-backend only.
• Add pino and create src/logger.ts (create file) exporting a configured logger with level from LOG_LEVEL.
• Replace the manual request log with a child logger bound to requestId, method, path, status, durationMs.
• Log errors from the final error handler at error level with the stack (but never the request body).
• Keep logs suppressed under NODE_ENV=test (or route to a silent transport) so test output stays clean.

Suggested execution

• Fork the repo and create a branch
• git checkout -b enhancement/observability-12-pino-logging
• Implement changes
  • Write code in: create src/logger.ts; update src/index.ts.
  • Write comprehensive tests in: src/__tests__/index.test.ts — assert the logger is invoked with the correlation id (spy/mock), and that test runs stay quiet.
  • Add documentation: document LOG_LEVEL in README.md.
  • Add TSDoc on the logger module.
  • Validate security: redact Authorization/X-Api-Key headers from logs.
• Test and commit

Test and commit

• Run npm run build, npm run lint, and npm test.
• Cover edge cases: error-path logging, redaction, level filtering.
• Paste full npm test output in the PR.

Example commit message

feat(observability): add pino structured logging with request correlation

Guidelines

• Minimum 95 percent test coverage for impacted code.
• Clear, reviewer-focused documentation.
• Timeframe: 96 hours.

Community & contribution rewards

• 💬 Join the StableRoute community on Discord for questions, reviews, and faster merges: https://discord.gg/37aCpusvx
• ⭐ This is a GrantFox OSS / Official Campaign task and may be rewarded. When your PR is merged you'll be prompted to rate the project — if this issue and the maintainers helped you ship, we'd be grateful for a 5-star rating. Clear questions in Discord and tidy, well-tested PRs are the fastest path to a merge and a reward.

[GBOYEE]

Hi maintainers! I can work on this — adding pino structured logging with request correlation.

Plan:

• Add pino and create src/logger.ts with level from LOG_LEVEL, suppressed under test
• Replace the manual console.log in the timing middleware with a child logger bound to requestId
• Add error-level logging from the handler with stack traces, redacting Authorization/X-Api-Key headers
• Keep test output clean via silent transport when NODE_ENV=test

PR incoming shortly. Let me know if you have a preferred log format!