Metrics

The gateway exposes Prometheus metrics when metrics.enabled is true.

Deep dive:

• Metrics registry wrapper: Registry
• Protocol metrics collectors: Protocol metrics

See also:

• Architecture: Observability
• Guide: Troubleshooting

Endpoint

Mounting is done by the server/runtime. The handler is built by:

• pkg/gateway/metrics.(*Registry).Handler

Exported metrics

All protocol metrics are labeled by:

• protocol: http, websocket, sse, grpc, or unknown
• product: derived from X-Router-Product or URL prefixes (e.g. trade, task, unknown)

gateway_protocol_requests_total

Counter of proxied requests labeled by:

• protocol
• product
• outcome (success or error)

gateway_protocol_inflight

Gauge of in-flight proxied requests labeled by:

• protocol
• product

gateway_protocol_request_duration_seconds

Histogram of upstream request duration labeled by:

• protocol
• product

gateway_protocol_active_connections

Gauge of active long-lived connections labeled by:

• protocol
• product

Notes:

• Websockets are tracked via hijack lifecycle hooks.
• SSE and gRPC are tracked as “connections” for concurrency visibility.