Send Subsonic formatted response on marshalling errors

server/subsonic/api.go

@@ -233,7 +233,7 @@ func h501(r chi.Router, paths ...string) {
 	for _, path := range paths {
 		handle := func(w http.ResponseWriter, r *http.Request) {
 			w.Header().Add("Cache-Control", "no-cache")
-			w.WriteHeader(501)
+			w.WriteHeader(http.StatusNotImplemented)
 			_, _ = w.Write([]byte("This endpoint is not implemented, but may be in future releases"))
 		}
 		addHandler(r, path, handle)
@@ -244,7 +244,7 @@ func h501(r chi.Router, paths ...string) {
 func h410(r chi.Router, paths ...string) {
 	for _, path := range paths {
 		handle := func(w http.ResponseWriter, r *http.Request) {
-			w.WriteHeader(410)
+			w.WriteHeader(http.StatusGone)
 			_, _ = w.Write([]byte("This endpoint will not be implemented"))
 		}
 		addHandler(r, path, handle)
@@ -276,7 +276,7 @@ func mapToSubsonicError(err error) subError {
 func sendError(w http.ResponseWriter, r *http.Request, err error) {
 	subErr := mapToSubsonicError(err)
 	response := newResponse()
-	response.Status = "failed"
+	response.Status = responses.StatusFailed
 	response.Error = &responses.Error{Code: int32(subErr.code), Message: subErr.Error()}
 
 	sendResponse(w, r, response)
@@ -305,11 +305,10 @@ func sendResponse(w http.ResponseWriter, r *http.Request, payload *responses.Sub
 	// This should never happen, but if it does, we need to know
 	if err != nil {
 		log.Error(r.Context(), "Error marshalling response", "format", f, err)
-		w.WriteHeader(http.StatusInternalServerError)
-		_, _ = w.Write([]byte("Internal Server Error: " + err.Error()))
+		sendError(w, r, err)
 		return
 	}
-	if payload.Status == "ok" {
+	if payload.Status == responses.StatusOK {
 		if log.IsGreaterOrEqualTo(log.LevelTrace) {
 			log.Debug(r.Context(), "API: Successful response", "endpoint", r.URL.Path, "status", "OK", "body", string(response))
 		} else {