TUN-7253: Adopt http.ResponseWriter for connection.ResponseWriter

proxy/proxy_test.go

@@ -700,8 +700,7 @@ func TestConnections(t *testing.T) {
 			cancel()
 			assert.Equal(t, test.want.err, err != nil)
 			assert.Equal(t, test.want.message, replayer.Bytes())
-			respPrinter := respWriter.(responsePrinter)
-			assert.Equal(t, test.want.headers, respPrinter.headers())
+			assert.Equal(t, test.want.headers, respWriter.Header())
 			replayer.rw.Reset()
 		})
 	}
@@ -794,10 +793,6 @@ func (p *pipedRequestBody) Close() error {
 	return nil
 }
 
-type responsePrinter interface {
-	headers() http.Header
-}
-
 type wsRespWriter struct {
 	w               io.Writer
 	responseHeaders http.Header
@@ -836,12 +831,16 @@ func (w *wsRespWriter) AddTrailer(trailerName, trailerValue string) {
 }
 
 // respHeaders is a test function to read respHeaders
-func (w *wsRespWriter) headers() http.Header {
+func (w *wsRespWriter) Header() http.Header {
 	// Removing indeterminstic header because it cannot be asserted.
 	w.responseHeaders.Del("Date")
 	return w.responseHeaders
 }
 
+func (w *wsRespWriter) WriteHeader(status int) {
+	// unused
+}
+
 type mockTCPRespWriter struct {
 	w               io.Writer
 	responseHeaders http.Header
@@ -862,7 +861,7 @@ func (m *mockTCPRespWriter) Write(p []byte) (n int, err error) {
 	return m.w.Write(p)
 }
 
-func (w *mockTCPRespWriter) AddTrailer(trailerName, trailerValue string) {
+func (m *mockTCPRespWriter) AddTrailer(trailerName, trailerValue string) {
 	// do nothing
 }
 
@@ -873,10 +872,14 @@ func (m *mockTCPRespWriter) WriteRespHeaders(status int, header http.Header) err
 }
 
 // respHeaders is a test function to read respHeaders
-func (m *mockTCPRespWriter) headers() http.Header {
+func (m *mockTCPRespWriter) Header() http.Header {
 	return m.responseHeaders
 }
 
+func (m *mockTCPRespWriter) WriteHeader(status int) {
+	// do nothing
+}
+
 func createSingleIngressConfig(t *testing.T, service string) ingress.Ingress {
 	ingressConfig := &config.Configuration{
 		Ingress: []config.UnvalidatedIngressRule{