Logging

How services write logs.

• Log through pino, never console. Take logger from @openperf/server/logging and make one child per component, named in kebab-case: logger.child({ module: "ingest-drainer" }). In api, use Nest’s Logger, but never its log() level.
• Pass fields first and a static message second, with errors as err: log.error({ table, err: error }, "Draining paused").
• A request writes one record when it ends. Add facts to it instead of logging again: PinoLogger.assign() in Nest apps, assignLogContext() in Bun apps. A failed request adds its error there as err.
• Only an app’s main.ts configures logging. Library code takes no logger and no callback that only logs.
• Wrap pg-boss handlers in handleJobs from @openperf/server/jobs, so failures are logged once with their queue and jobId.
• In tests, assert logs with recordLogs() from @openperf/server/logging/testing.