TUN-5837: Log panic recovery in http2 logic with debug level log

connection/http2.go

@@ -100,7 +100,7 @@ func (c *HTTP2Connection) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	connType := determineHTTP2Type(r)
 	handleMissingRequestParts(connType, r)
 
-	respWriter, err := NewHTTP2RespWriter(r, w, connType)
+	respWriter, err := NewHTTP2RespWriter(r, w, connType, c.log)
 	if err != nil {
 		c.observer.log.Error().Msg(err.Error())
 		return
@@ -163,14 +163,16 @@ type http2RespWriter struct {
 	w           http.ResponseWriter
 	flusher     http.Flusher
 	shouldFlush bool
+	log         *zerolog.Logger
 }
 
-func NewHTTP2RespWriter(r *http.Request, w http.ResponseWriter, connType Type) (*http2RespWriter, error) {
+func NewHTTP2RespWriter(r *http.Request, w http.ResponseWriter, connType Type, log *zerolog.Logger) (*http2RespWriter, error) {
 	flusher, isFlusher := w.(http.Flusher)
 	if !isFlusher {
 		respWriter := &http2RespWriter{
-			r: r.Body,
-			w: w,
+			r:   r.Body,
+			w:   w,
+			log: log,
 		}
 		respWriter.WriteErrorResponse()
 		return nil, fmt.Errorf("%T doesn't implement http.Flusher", w)
@@ -181,6 +183,7 @@ func NewHTTP2RespWriter(r *http.Request, w http.ResponseWriter, connType Type) (
 		w:           w,
 		flusher:     flusher,
 		shouldFlush: connType.shouldFlush(),
+		log:         log,
 	}, nil
 }
 
@@ -239,7 +242,7 @@ func (rp *http2RespWriter) Write(p []byte) (n int, err error) {
 		// Implementer of OriginClient should make sure it doesn't write to the connection after Proxy returns
 		// Register a recover routine just in case.
 		if r := recover(); r != nil {
-			println(fmt.Sprintf("Recover from http2 response writer panic, error %s", debug.Stack()))
+			rp.log.Debug().Msgf("Recover from http2 response writer panic, error %s", debug.Stack())
 		}
 	}()
 	n, err = rp.w.Write(p)