refactoring code

pkg/proxy/proxy.go

@@ -37,13 +37,13 @@ func NewProxy(cache string) http.Handler {
 				version := strings.TrimSuffix(mod[1], suffix)
 				version, err = module.DecodeVersion(version)
 				if err != nil {
-					ReturnServerError(w, err)
+					ReturnInternalServerError(w, err)
 					return
 				}
 				modPath := strings.TrimPrefix(mod[0], "/")
 				modPath, err := module.DecodePath(modPath)
 				if err != nil {
-					ReturnServerError(w, err)
+					ReturnInternalServerError(w, err)
 					return
 				}
 				// ignore the error, incorrect tag may be given
@@ -59,13 +59,13 @@ func NewProxy(cache string) http.Handler {
 				modPath = strings.TrimPrefix(modPath, "/")
 				modPath, err := module.DecodePath(modPath)
 				if err != nil {
-					ReturnServerError(w, err)
+					ReturnInternalServerError(w, err)
 					return
 				}
 				repo, err := modfetch.Lookup(modPath)
 				if err != nil {
 					errLogger.Printf("lookup failed: %v", err)
-					ReturnServerError(w, err)
+					ReturnInternalServerError(w, err)
 					return
 				}
 				rev, err := repo.Stat("latest")

pkg/proxy/response.go

@@ -9,15 +9,15 @@ import (
 
 var errLogger = log.New(os.Stderr, "", log.LstdFlags)
 
-func ReturnServerError(w http.ResponseWriter, err error) {
-	w.WriteHeader(500)
+func ReturnInternalServerError(w http.ResponseWriter, err error) {
+	w.WriteHeader(http.StatusInternalServerError)
 	msg := fmt.Sprintf("%v", err)
 	errLogger.Printf("goproxy: %s\n", msg)
 	_, _ = w.Write([]byte(msg))
 }
 
 func ReturnBadRequest(w http.ResponseWriter, err error) {
-	w.WriteHeader(400)
+	w.WriteHeader(http.StatusBadRequest)
 	msg := fmt.Sprintf("%v", err)
 	errLogger.Printf("goproxy: %s\n", msg)
 	_, _ = w.Write([]byte(msg))