feat(telemetry): add axum_middleware

src/axum_middleware.rs

@@ -0,0 +1,72 @@
+#[cfg(all(feature = "response", feature = "telemetry"))]
+use axum::{
+    extract::{ConnectInfo, MatchedPath, Request},
+    middleware::Next,
+    response::Response,
+};
+
+#[cfg(all(feature = "response", feature = "telemetry"))]
+use std::net::SocketAddr;
+
+#[cfg(all(feature = "response", feature = "telemetry"))]
+use tracing::field;
+
+#[cfg(all(feature = "response", feature = "telemetry"))]
+fn first_forwarded_for(req: &Request) -> Option<String> {
+    let raw = req.headers().get("x-forwarded-for")?.to_str().ok()?;
+    raw.split(',')
+        .next()
+        .map(|s| s.trim())
+        .filter(|s| !s.is_empty())
+        .map(|s| s.to_string())
+}
+
+#[cfg(all(feature = "response", feature = "telemetry"))]
+fn connect_info_ip(req: &Request) -> Option<String> {
+    req.extensions()
+        .get::<ConnectInfo<SocketAddr>>()
+        .map(|ci| ci.0.ip().to_string())
+}
+
+#[cfg(all(feature = "response", feature = "telemetry"))]
+fn matched_route(req: &Request) -> Option<String> {
+    req.extensions()
+        .get::<MatchedPath>()
+        .map(|m| m.as_str().to_string())
+}
+
+#[cfg(all(feature = "response", feature = "telemetry"))]
+fn request_id(req: &Request) -> Option<String> {
+    req.headers()
+        .get("x-request-id")
+        .and_then(|v| v.to_str().ok())
+        .map(|s| s.to_string())
+}
+
+#[cfg(all(feature = "response", feature = "telemetry"))]
+pub async fn trace_http_request(req: Request, next: Next) -> Response {
+    let method = req.method().to_string();
+    let path = req.uri().path().to_string();
+    let route = matched_route(&req).unwrap_or_else(|| path.clone());
+    let client_ip = first_forwarded_for(&req).or_else(|| connect_info_ip(&req));
+    let req_id = request_id(&req);
+
+    let span = tracing::info_span!(
+        "http.request",
+        http.method = %method,
+        http.path = %path,
+        http.route = %route,
+        client.ip = %client_ip.clone().unwrap_or_else(|| "unknown".into()),
+        request_id = %req_id.clone().unwrap_or_else(|| "unknown".into()),
+        tenant_id = field::Empty,
+        user_id = field::Empty,
+        status = field::Empty,
+    );
+
+    let _guard = span.enter();
+    let resp = next.run(req).await;
+    let status = resp.status().as_u16();
+    tracing::Span::current().record("status", status);
+    resp
+}
+