From 6771293336b214874a904f7d6d4bfcab35b3f165 Mon Sep 17 00:00:00 2001
From: yusing <yusing.wys@gmail.com>
Date: Mon, 8 Dec 2025 13:45:53 +0800
Subject: [PATCH] fix(middleware): enhance response modification handling in
 ServeHTTP

- Replaced ResponseModifier with new LazyResponseModifier.
- Added logic to skip modification for non-HTML content.
---
 goutils                                      |  2 +-
 internal/net/gphttp/middleware/middleware.go | 18 +++++++++++++++---
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/goutils b/goutils
index 22ec8782..316d9a68 160000
--- a/goutils
+++ b/goutils
@@ -1 +1 @@
-Subproject commit 22ec87826e64f18080a31a1d58345346a012e244
+Subproject commit 316d9a68f489545718910440a737bccc6d429a33
diff --git a/internal/net/gphttp/middleware/middleware.go b/internal/net/gphttp/middleware/middleware.go
index 731256e8..77fb38af 100644
--- a/internal/net/gphttp/middleware/middleware.go
+++ b/internal/net/gphttp/middleware/middleware.go
@@ -197,10 +197,16 @@ func (m *Middleware) ServeHTTP(next http.HandlerFunc, w http.ResponseWriter, r *
 	}
 
 	if exec, ok := m.impl.(ResponseModifier); ok {
-		rm := httputils.NewResponseModifier(w)
-		defer rm.FlushRelease()
-		next(rm, r)
+		lrm := httputils.NewLazyResponseModifier(w, needsBuffering)
+		defer lrm.FlushRelease()
+		next(lrm, r)
 
+		// Skip modification if response wasn't buffered (non-HTML content)
+		if !lrm.IsBuffered() {
+			return
+		}
+
+		rm := lrm.ResponseModifier()
 		currentBody := rm.BodyReader()
 		currentResp := &http.Response{
 			StatusCode:    rm.StatusCode(),
@@ -228,6 +234,12 @@ func (m *Middleware) ServeHTTP(next http.HandlerFunc, w http.ResponseWriter, r *
 	}
 }
 
+// needsBuffering determines if a response should be buffered for modification.
+// Only HTML responses need buffering; streaming content (video, audio, etc.) should pass through.
+func needsBuffering(header http.Header) bool {
+	return httputils.GetContentType(header).IsHTML()
+}
+
 func (m *Middleware) LogWarn(req *http.Request) *zerolog.Event {
 	return log.Warn().Str("middleware", m.name).
 		Str("host", req.Host).