Site24x7 APM tester
Click a button to produce an error. Watch Site24x7 APM Insight → Errors / Web Transactions, and the URL monitors on /health and /ready.
APM agent loaded: unknown
Health toggles (URL-monitor signal)
Toggle /health broken
Flips /health between 200 and 500. Watch the URL monitor go DOWN within 1–5 min.
Toggle /ready broken
Marks fake upstream unhealthy → /ready returns 503. Verifies readiness probes.
Clear memory hog
Drops retained buffers so RSS drops back down (and GC runs if --expose-gc).
HTTP errors (APM Web Transactions + Errors)
500 (sync throw)
Handler throws synchronously. Classic 5xx trace in APM.
500 (async throw)
Awaited rejection. Tests APM's promise-aware stack capture.
Downstream 5xx
Outbound fetch → external 500. APM should show the external service + failure.
Caught + silent (200)
Response is 200 OK but error reported via apm.noticeError. Invisible to URL monitors.
Process-level (needs APM / supervisor)
Unhandled rejection
Floating promise, no .catch. APM should report it via process.on('unhandledRejection').
⚠ CRASH process (uncaught)
Throws from setImmediate. Process exits — watch the URL monitor go DOWN and recovery (if PM2/K8s restarts it).