Prometheus FastAPI Instrumentator

Allows regex-based route ignoring, environment variable control for instrumentation, and custom label configuration, as detailed in the 'Advanced Usage' section with options like should_ignore_untemplated and excluded_handlers.

Supports selecting from pre-built metrics (e.g., latency, request_size) or creating custom ones via closures, enabling tailored monitoring without boilerplate code, as shown in the 'Adding metrics' and 'Creating new metrics' examples.

Includes sensible defaults like grouped status codes and low-cardinality histograms to balance detail with performance, and offers gzip compression for the metrics endpoint to reduce network bandwidth, mentioned in the 'Features' and 'Exposing endpoint' sections.

Provides a fast track with minimal code (Instrumentator().instrument(app).expose(app)) to get started with default HTTP metrics like request counts and latencies, making it accessible for basic use cases.