fix(rustproxy-http,rustproxy-metrics): fix domain-scoped request host detection and harden connection metrics cleanup

rust/crates/rustproxy-http/src/h3_service.rs

@@ -11,8 +11,8 @@ use std::task::{Context, Poll};
 
 use bytes::{Buf, Bytes};
 use http_body::Frame;
-use http_body_util::BodyExt;
 use http_body_util::combinators::BoxBody;
+use http_body_util::BodyExt;
 use tracing::{debug, warn};
 
 use rustproxy_config::RouteConfig;
@@ -49,7 +49,8 @@ impl H3ProxyService {
         debug!("HTTP/3 connection from {} on port {}", remote_addr, port);
 
         // Track frontend H3 connection for the QUIC connection's lifetime.
-        let _frontend_h3_guard = ProtocolGuard::frontend(Arc::clone(self.http_proxy.metrics()), "h3");
+        let _frontend_h3_guard =
+            ProtocolGuard::frontend(Arc::clone(self.http_proxy.metrics()), "h3");
 
         let mut h3_conn: h3::server::Connection<h3_quinn::Connection, Bytes> =
             h3::server::builder()
@@ -92,8 +93,15 @@ impl H3ProxyService {
 
             tokio::spawn(async move {
                 if let Err(e) = handle_h3_request(
-                    request, stream, port, remote_addr, &http_proxy, request_cancel,
-                ).await {
+                    request,
+                    stream,
+                    port,
+                    remote_addr,
+                    &http_proxy,
+                    request_cancel,
+                )
+                .await
+                {
                     debug!("HTTP/3 request error from {}: {}", remote_addr, e);
                 }
             });
@@ -153,11 +161,14 @@ async fn handle_h3_request(
     // Delegate to HttpProxyService — same backend path as TCP/HTTP:
     // route matching, ALPN protocol detection, connection pool, H1/H2/H3 auto.
     let conn_activity = ConnActivity::new_standalone();
-    let response = http_proxy.handle_request(req, peer_addr, port, cancel, conn_activity).await
+    let response = http_proxy
+        .handle_request(req, peer_addr, port, cancel, conn_activity)
+        .await
         .map_err(|e| anyhow::anyhow!("Backend request failed: {}", e))?;
 
     // Await the body reader to get the H3 stream back
-    let mut stream = body_reader.await
+    let mut stream = body_reader
+        .await
         .map_err(|e| anyhow::anyhow!("Body reader task failed: {}", e))?;
 
     // Send response headers over H3 (skip hop-by-hop headers)
@@ -170,10 +181,13 @@ async fn handle_h3_request(
         }
         h3_response = h3_response.header(name, value);
     }
-    let h3_response = h3_response.body(())
+    let h3_response = h3_response
+        .body(())
         .map_err(|e| anyhow::anyhow!("Failed to build H3 response: {}", e))?;
 
-    stream.send_response(h3_response).await
+    stream
+        .send_response(h3_response)
+        .await
         .map_err(|e| anyhow::anyhow!("Failed to send H3 response: {}", e))?;
 
     // Stream response body back over H3
@@ -182,7 +196,9 @@ async fn handle_h3_request(
         match frame {
             Ok(frame) => {
                 if let Ok(data) = frame.into_data() {
-                    stream.send_data(data).await
+                    stream
+                        .send_data(data)
+                        .await
                         .map_err(|e| anyhow::anyhow!("Failed to send H3 data: {}", e))?;
                 }
             }
@@ -194,7 +210,9 @@ async fn handle_h3_request(
     }
 
     // Finish the H3 stream (send QUIC FIN)
-    stream.finish().await
+    stream
+        .finish()
+        .await
         .map_err(|e| anyhow::anyhow!("Failed to finish H3 stream: {}", e))?;
 
     Ok(())