Fixes wrap around http.ResponseWriter

response_writer.go

@@ -0,0 +1,47 @@
+package gin
+
+import (
+	"net/http"
+)
+
+type (
+	ResponseWriter interface {
+		http.ResponseWriter
+		Status() int
+		Written() bool
+
+		// private
+		reset(http.ResponseWriter)
+		setStatus(int)
+	}
+
+	responseWriter struct {
+		http.ResponseWriter
+		status  int
+		written bool
+	}
+)
+
+func (w *responseWriter) reset(writer http.ResponseWriter) {
+	w.ResponseWriter = writer
+	w.status = 0
+	w.written = false
+}
+
+func (w *responseWriter) setStatus(code int) {
+	w.status = code
+}
+
+func (w *responseWriter) WriteHeader(code int) {
+	w.status = code
+	w.written = true
+	w.ResponseWriter.WriteHeader(code)
+}
+
+func (w *responseWriter) Status() int {
+	return w.status
+}
+
+func (w *responseWriter) Written() bool {
+	return w.written
+}