shutdown h2 connection gracefully with GOAWAYs

Co-authored-by: Matthew Gumport <[email protected]>
Includes-commit: 15e5c64ce46da5e061f2c84ce45cdddedf2f6058
Replicated-from: https://github.com/cloudflare/pingora/pull/415

2 files changed, 12 insertions, 3 deletions

diff --git a/.bleep b/.bleep
index 26298b0..0c316c3 100644
--- a/.bleep
+++ b/.bleep
@@ -1 +1 @@
-78684dca2f7fe5d952d3b01faec526a1b1cbad8c
\ No newline at end of file
+a4032182c556d6fee5f22d0b56b99b03c8fc6868
\ No newline at end of file
diff --git a/pingora-core/src/apps/mod.rs b/pingora-core/src/apps/mod.rs
index 0786d08..2a77a3d 100644
--- a/pingora-core/src/apps/mod.rs
+++ b/pingora-core/src/apps/mod.rs
@@ -20,6 +20,7 @@ pub mod prometheus_http_app;
 use crate::server::ShutdownWatch;
 use async_trait::async_trait;
 use log::{debug, error};
+use std::future::poll_fn;
 use std::sync::Arc;
 
 use crate::protocols::http::v2::server;
@@ -148,11 +149,19 @@ where
                 Ok(c) => c,
             };
 
+            let mut shutdown = shutdown.clone();
             loop {
                 // this loop ends when the client decides to close the h2 conn
                 // TODO: add a timeout?
-                let h2_stream =
-                    server::HttpSession::from_h2_conn(&mut h2_conn, digest.clone()).await;
+                let h2_stream = tokio::select! {
+                    _ = shutdown.changed() => {
+                        h2_conn.graceful_shutdown();
+                        let _ = poll_fn(|cx| h2_conn.poll_closed(cx))
+                            .await.map_err(|e| error!("H2 error waiting for shutdown {e}"));
+                        return None;
+                    }
+                    h2_stream = server::HttpSession::from_h2_conn(&mut h2_conn, digest.clone()) => h2_stream
+                };
                 let h2_stream = match h2_stream {
                     Err(e) => {
                         // It is common for the client to just disconnect TCP without properly