fix: set Content-Type to application/json when responding with json (#64

)

* fix: set Content-Type to application/json when responding with json

* test: check for response Content-Type to be application/json

httperr.go

@@ -70,7 +70,11 @@ func DefaultErrorHandler(w http.ResponseWriter, err error, status int) {
 	bts, _ := json.Marshal(errorResponse{
 		Error: msg,
 	})
-	http.Error(w, string(bts), status)
+
+	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	w.Header().Set("X-Content-Type-Options", "nosniff")
+	w.WriteHeader(status)
+	fmt.Fprintln(w, string(bts))
 }
 
 // NewWithHandler() wraps a given http.Handler and returns a http.Handler.

httperr_test.go

@@ -41,6 +41,11 @@ func TestServeHTTPError(t *testing.T) {
 		t.Fatalf("expected http status %d, got %d", status, resp.StatusCode)
 	}
 
+	contentType := "application/json; charset=utf-8"
+	if resp.Header.Get("Content-Type") != contentType {
+		t.Fatalf("expected Content-Type '%s', got '%s'", contentType, resp.Header.Get("Content-Type"))
+	}
+
 	bts, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
 		t.Fatalf("got error: %v", err)
@@ -64,6 +69,11 @@ func TestServeError(t *testing.T) {
 		t.Fatalf("expected http status %d, got %d", status, resp.StatusCode)
 	}
 
+	contentType := "application/json; charset=utf-8"
+	if resp.Header.Get("Content-Type") != contentType {
+		t.Fatalf("expected Content-Type '%s', got '%s'", contentType, resp.Header.Get("Content-Type"))
+	}
+
 	bts, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
 		t.Fatalf("got error: %v", err)