tweak(entrypoint): introducing ResponseRecorder specialized for access logger for better throughput

internal/logging/accesslog/response_recorder.go

@@ -0,0 +1,67 @@
+package accesslog
+
+import (
+	"bufio"
+	"fmt"
+	"net"
+	"net/http"
+)
+
+type ResponseRecorder struct {
+	w http.ResponseWriter
+
+	resp http.Response
+}
+
+func NewResponseRecorder(w http.ResponseWriter) *ResponseRecorder {
+	return &ResponseRecorder{
+		w: w,
+		resp: http.Response{
+			StatusCode: http.StatusOK,
+			Header:     w.Header(),
+		},
+	}
+}
+
+func (w *ResponseRecorder) Unwrap() http.ResponseWriter {
+	return w.w
+}
+
+func (w *ResponseRecorder) Response() *http.Response {
+	return &w.resp
+}
+
+func (w *ResponseRecorder) Header() http.Header {
+	return w.w.Header()
+}
+
+func (w *ResponseRecorder) Write(b []byte) (int, error) {
+	n, err := w.w.Write(b)
+	w.resp.ContentLength += int64(n)
+	return n, err
+}
+
+func (w *ResponseRecorder) WriteHeader(code int) {
+	w.w.WriteHeader(code)
+
+	if code >= http.StatusContinue && code < http.StatusOK {
+		return
+	}
+	w.resp.StatusCode = code
+}
+
+// Hijack hijacks the connection.
+func (w *ResponseRecorder) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	if h, ok := w.w.(http.Hijacker); ok {
+		return h.Hijack()
+	}
+
+	return nil, nil, fmt.Errorf("not a hijacker: %T", w.w)
+}
+
+// Flush sends any buffered data to the client.
+func (w *ResponseRecorder) Flush() {
+	if flusher, ok := w.w.(http.Flusher); ok {
+		flusher.Flush()
+	}
+}