refactor(http): proper ResponseWriter and headers handling across files

internal/net/gphttp/middleware/modify_html.go

@@ -45,13 +45,25 @@ func (m *modifyHTML) modifyResponse(resp *http.Response) error {
 		return nil
 	}
 
+	// Skip modification for streaming/chunked responses to avoid blocking reads
+	// Unknown content length or any transfer encoding indicates streaming.
+	if resp.ContentLength < 0 || len(resp.TransferEncoding) > 0 {
+		return nil
+	}
+
 	// NOTE: do not put it in the defer, it will be used as resp.Body
 	content, release, err := httputils.ReadAllBody(resp)
 	resp.Body.Close()
 	if err != nil {
 		log.Err(err).Str("url", fullURL(resp.Request)).Msg("failed to read response body")
+		// Fail open: do not abort the response. Return an empty body safely.
+		resp.ContentLength = 0
+		resp.Header.Set("Content-Length", "0")
+		resp.Header.Del("Transfer-Encoding")
+		resp.Header.Del("Trailer")
+		resp.Header.Del("Content-Encoding")
 		resp.Body = eofReader{}
-		return err
+		return nil
 	}
 
 	doc, err := goquery.NewDocumentFromReader(bytes.NewReader(content))
@@ -92,6 +104,9 @@ func (m *modifyHTML) modifyResponse(resp *http.Response) error {
 	release(content)
 	resp.ContentLength = int64(buf.Len())
 	resp.Header.Set("Content-Length", strconv.Itoa(buf.Len()))
+	resp.Header.Del("Transfer-Encoding")
+	resp.Header.Del("Trailer")
+	resp.Header.Del("Content-Encoding")
 	resp.Header.Set("Content-Type", "text/html; charset=utf-8")
 	resp.Body = readerWithRelease(buf.Bytes(), func(_ []byte) {
 		pool.PutBuffer(buf)

internal/route/rules/response_modifier.go

@@ -158,6 +158,8 @@ func (rm *ResponseModifier) FlushRelease() (int, error) {
 		// }
 		contentLength := rm.ContentLength()
 		h.Set("Content-Length", strconv.Itoa(rm.ContentLength()))
+		h.Del("Transfer-Encoding")
+		h.Del("Trailer")
 		rm.w.WriteHeader(rm.StatusCode())
 
 		if contentLength > 0 {

internal/route/rules/rules.go

@@ -6,7 +6,7 @@ import (
 	"net/http"
 
 	"github.com/bytedance/sonic"
-	gperr "github.com/yusing/goutils/errs"
+	"github.com/rs/zerolog/log"
 )
 
 type (
@@ -89,6 +89,11 @@ func (rules Rules) BuildHandler(up http.HandlerFunc) http.HandlerFunc {
 		if defaultRule.IsResponseRule() {
 			return func(w http.ResponseWriter, r *http.Request) {
 				rm := NewResponseModifier(w)
+				defer func() {
+					if _, err := rm.FlushRelease(); err != nil {
+						logError(err, r)
+					}
+				}()
 				w = rm
 				up(w, r)
 				err := defaultRule.Do.exec.Handle(w, r)
@@ -99,6 +104,11 @@ func (rules Rules) BuildHandler(up http.HandlerFunc) http.HandlerFunc {
 		}
 		return func(w http.ResponseWriter, r *http.Request) {
 			rm := NewResponseModifier(w)
+			defer func() {
+				if _, err := rm.FlushRelease(); err != nil {
+					logError(err, r)
+				}
+			}()
 			w = rm
 			err := defaultRule.Do.exec.Handle(w, r)
 			if err == nil {
@@ -128,7 +138,7 @@ func (rules Rules) BuildHandler(up http.HandlerFunc) http.HandlerFunc {
 		rm := NewResponseModifier(w)
 		defer func() {
 			if _, err := rm.FlushRelease(); err != nil {
-				gperr.LogError("error executing rules", err)
+				logError(err, r)
 			}
 		}()
 
@@ -252,3 +262,7 @@ func (rule *Rule) Check(w http.ResponseWriter, r *http.Request) bool {
 func (rule *Rule) Handle(w http.ResponseWriter, r *http.Request) error {
 	return rule.Do.exec.Handle(w, r)
 }
+
+func logError(err error, r *http.Request) {
+	log.Err(err).Str("method", r.Method).Str("url", r.Host+r.URL.Path).Msg("error executing rules")
+}