feat: add X-Request-ID middleware for request tracking

- Generate UUID v4 per request or accept upstream ID - Store in request extensions for handler access - Add to response headers for client correlation - Include in tracing spans for log correlation
2026-04-12 09:10:32 +00:00 · 2026-01-26 00:02:27 +00:00
parent 697d59811a
commit ffc584351c
1 changed files with 92 additions and 0 deletions
--- a/nora-registry/src/request_id.rs
+++ b/nora-registry/src/request_id.rs
@@ -0,0 +1,92 @@
+//! Request ID middleware for request tracking and correlation
+//!
+//! Generates a unique ID for each request that can be used for:
+//! - Log correlation across services
+//! - Debugging production issues
+//! - Client error reporting
+
+use axum::{
+    body::Body,
+    http::{header::HeaderName, HeaderValue, Request},
+    middleware::Next,
+    response::Response,
+};
+use tracing::{info_span, Instrument};
+use uuid::Uuid;
+
+/// Header name for request ID
+pub static REQUEST_ID_HEADER: HeaderName = HeaderName::from_static("x-request-id");
+
+/// Request ID wrapper type for extraction from request extensions
+#[derive(Clone, Debug)]
+pub struct RequestId(pub String);
+
+impl std::ops::Deref for RequestId {
+    type Target = String;
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+/// Middleware that adds a unique request ID to each request.
+///
+/// The request ID is:
+/// 1. Taken from incoming `X-Request-ID` header if present (for upstream tracing)
+/// 2. Generated as a new UUID v4 if not present
+///
+/// The ID is:
+/// - Stored in request extensions for handlers to access
+/// - Added to the response `X-Request-ID` header
+/// - Included in the tracing span for log correlation
+pub async fn request_id_middleware(mut request: Request<Body>, next: Next) -> Response {
+    // Check if request already has an ID (from upstream proxy/gateway)
+    let request_id = request
+        .headers()
+        .get(&REQUEST_ID_HEADER)
+        .and_then(|v| v.to_str().ok())
+        .map(String::from)
+        .unwrap_or_else(|| Uuid::new_v4().to_string());
+
+    // Store in request extensions for handlers to access
+    request
+        .extensions_mut()
+        .insert(RequestId(request_id.clone()));
+
+    // Create tracing span with request metadata
+    let span = info_span!(
+        "request",
+        request_id = %request_id,
+        method = %request.method(),
+        uri = %request.uri().path(),
+    );
+
+    // Run the request handler within the span
+    let mut response = next.run(request).instrument(span).await;
+
+    // Add request ID to response headers
+    if let Ok(header_value) = HeaderValue::from_str(&request_id) {
+        response
+            .headers_mut()
+            .insert(&REQUEST_ID_HEADER, header_value);
+    }
+
+    response
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_request_id_deref() {
+        let id = RequestId("test-123".to_string());
+        assert_eq!(&*id, "test-123");
+    }
+
+    #[test]
+    fn test_request_id_clone() {
+        let id = RequestId("test-123".to_string());
+        let cloned = id.clone();
+        assert_eq!(id.0, cloned.0);
+    }
+}