Add support for gRPC-web module to bridge gRPC-web client requests to gRPC server requests

2 files changed, 27 insertions, 13 deletions

diff --git a/pingora-proxy/src/lib.rs b/pingora-proxy/src/lib.rs
index 890af98..5621170 100644
--- a/pingora-proxy/src/lib.rs
+++ b/pingora-proxy/src/lib.rs
@@ -405,7 +405,20 @@ impl Session {
                     self.downstream_modules_ctx
                         .response_body_filter(data, *end)?;
                 }
-                _ => { /* HttpModules doesn't handle trailer yet */ }
+                HttpTask::Trailer(trailers) => {
+                    if let Some(buf) = self
+                        .downstream_modules_ctx
+                        .response_trailer_filter(trailers)?
+                    {
+                        // Write the trailers into the body if the filter
+                        // returns a buffer.
+                        //
+                        // Note, this will not work if end of stream has already
+                        // been seen or we've written content-length bytes.
+                        *task = HttpTask::Body(Some(buf), true);
+                    }
+                }
+                _ => { /* Done or Failed */ }
             }
         }
         self.downstream_session.response_duplex_vec(tasks).await
diff --git a/pingora-proxy/src/proxy_h2.rs b/pingora-proxy/src/proxy_h2.rs
index 5216ee9..0750160 100644
--- a/pingora-proxy/src/proxy_h2.rs
+++ b/pingora-proxy/src/proxy_h2.rs
@@ -124,6 +124,9 @@ impl<SV> HttpProxy<SV> {
         session.upstream_compression.request_filter(&req);
         let body_empty = session.as_mut().is_body_empty();
 
+        // whether we support sending END_STREAM on HEADERS if body is empty
+        let send_end_stream = req.send_end_stream().expect("req must be h2");
+
         let mut req: http::request::Parts = req.into();
 
         // H2 requires authority to be set, so copy that from H1 host if that is set
@@ -133,27 +136,25 @@ impl<SV> HttpProxy<SV> {
             }
         }
 
-        debug!("Request to h2: {:?}", req);
+        debug!("Request to h2: {req:?}");
 
-        // don't send END_STREAM on HEADERS for no_header_eos
-        let send_header_eos = !peer.options.no_header_eos && body_empty;
+        // send END_STREAM on HEADERS
+        let send_header_eos = send_end_stream && body_empty;
+        debug!("send END_STREAM on HEADERS: {send_end_stream}");
 
         let req = Box::new(RequestHeader::from(req));
-        match client_session.write_request_header(req, send_header_eos) {
-            Ok(v) => v,
-            Err(e) => {
-                return (false, Some(e.into_up()));
-            }
-        };
+        if let Err(e) = client_session.write_request_header(req, send_header_eos) {
+            return (false, Some(e.into_up()));
+        }
 
-        // send END_STREAM on empty DATA frame for no_headers_eos
-        if peer.options.no_header_eos && body_empty {
+        if !send_end_stream && body_empty {
+            // send END_STREAM on empty DATA frame
             match client_session.write_request_body(Bytes::new(), true) {
                 Ok(()) => debug!("sent empty DATA frame to h2"),
                 Err(e) => {
                     return (false, Some(e.into_up()));
                 }
-            };
+            }
         }
 
         client_session.read_timeout = peer.options.read_timeout;