Impact GateGuides
API usage observability with Prometheus or Datadog
How to match runtime request metrics to the endpoints in your OpenAPI contracts so you can see which routes are used and which are not.
On this page
Why static analysis alone leaves usage unknown#
Code analysis shows callers it can find. Runtime metrics show traffic that actually arrives. Together they give a fuller picture, and neither one proves an endpoint is unused.
What you need#
- A request counter with provider service, HTTP method, and a stable route template such as /orders/{id}. Full URLs with customer IDs cannot be matched.
- Prometheus gives estimated request counts from counter increases. Datadog gives counts of indexed APM spans.
- Caller identity is optional and present only if your source records it.
Impact Gate reads your existing Prometheus or Datadog data and matches it to endpoints discovered in your repositories. Datadog needs an API key and an application key with apm_read. See the runtime observability guide for the setup steps.