Add finish_downstream_session to ProxyHttp

pingora-http/src/lib.rs

@@ -323,6 +323,17 @@ impl RequestHeader {
         self.base.version = version;
     }
 
+    /// Return the host from the request.
+    ///
+    /// Checks (in order): `:authority` pseudo-header (HTTP/2), `Host` header (HTTP/1), URI host.
+    pub fn host(&self) -> Option<&str> {
+        self.headers
+            .get(":authority")
+            .or_else(|| self.headers.get(http::header::HOST))
+            .and_then(|v| v.to_str().ok())
+            .or_else(|| self.uri.host())
+    }
+
     /// Clone `self` into [http::request::Parts].
     pub fn as_owned_parts(&self) -> ReqParts {
         clone_req_parts(&self.base)

pingora-proxy/src/lib.rs

@@ -656,12 +656,10 @@ where
                     self.inner.logging(&mut session, None, &mut ctx).await;
                     self.cleanup_sub_req(&mut session);
                     let persistent_settings = HttpPersistentSettings::for_session(&session);
-                    return session
-                        .downstream_session
-                        .finish()
+                    return self
+                        .inner
+                        .finish_downstream_session(session.downstream_session, &mut ctx)
                         .await
-                        .ok()
-                        .flatten()
                         .map(|s| ReusedHttpStream::new(s, Some(persistent_settings)));
                 }
                 /* else continue */

pingora-proxy/src/proxy_trait.rs

@@ -578,6 +578,17 @@ pub trait ProxyHttp {
     ) -> Result<()> {
         Ok(())
     }
+
+    /// Called when response_sent is true from request_filter, allowing custom handling of the downstream session.
+    ///
+    /// Returns an optional Stream if the connection can be reused.
+    async fn finish_downstream_session(
+        &self,
+        downstream_session: Box<HttpSession>,
+        _ctx: &mut Self::CTX,
+    ) -> Option<Stream> {
+        downstream_session.finish().await.ok().flatten()
+    }
 }
 
 /// Context struct returned by `fail_to_proxy`.