axum-otel-metrics

axum OpenTelemetry metrics middleware with prometheus exporter

axum is an ergonomic and modular web framework built with Tokio, Tower, and Hyper

be default, the metrics will be exported at /metrics endpoint. and below metrics will be exported:

requestdurationseconds histogram request_duration_seconds_bucket request_duration_seconds_sum request_duration_seconds_count

requests_total counter

requests_total

labels for request_duration_seconds and requests_total:

method path status

Usage

```rust use axumotelmetrics::HttpMetricsLayerBuilder;

let metrics = HttpMetricsLayerBuilder::new() .build();

let app = Router::new() // export metrics at /metrics endpoint .merge(metrics.routes()) .route("/", get(handler)) .route("/hello", get(handler)) .route("/world", get(handler)) // add the metrics middleware .layer(metrics); ```

Usage with State

```rust use axumotelmetrics::HttpMetricsLayerBuilder;

[derive(Clone)]

pub struct SharedState { }

let state = SharedState { };

let metrics = HttpMetricsLayerBuilder::new() .build();

let app = Router::new() // export metrics at /metrics endpoint .merge(metrics.routes::()) .route("/", get(handler)) .route("/hello", get(handler)) .route("/world", get(handler)) // add the metrics middleware .layer(metrics) .with_state(state.clone()); ```

OpenTelemetry Rust Instrumentation Status and Releases

https://opentelemetry.io/docs/instrumentation/rust/#status-and-releases

| Traces | Metrics | Logs | |--------------------------------------------------------------------------------------------------|---------|---------------------| | Stable | Alpha | Not yet implemented |

OpenTelemetry Metrics Exporter

Push Metric Exporter https://opentelemetry.io/docs/reference/specification/metrics/sdk/#push-metric-exporter

Pull Metric Exporter https://opentelemetry.io/docs/reference/specification/metrics/sdk/#pull-metric-exporter

exporters

https://opentelemetry.io/docs/reference/specification/metrics/sdk_exporters/

In-memory https://opentelemetry.io/docs/reference/specification/metrics/sdk_exporters/in-memory/

Prometheus https://opentelemetry.io/docs/reference/specification/metrics/sdk_exporters/prometheus/

OTLP https://opentelemetry.io/docs/reference/specification/metrics/sdk_exporters/otlp/

Standard output https://opentelemetry.io/docs/reference/specification/metrics/sdk_exporters/stdout/

Metrics Data Model

https://opentelemetry.io/docs/reference/specification/metrics/data-model/