KEYCLOAK-4037 JS Adapter fails in Cordova mode for iOS apps

adapters/oidc/js/src/main/resources/keycloak.js

@@ -587,7 +587,7 @@
 
                 req.onreadystatechange = function () {
                     if (req.readyState == 4) {
-                        if (req.status == 200) {
+                        if (req.status == 200 || fileLoaded(req)) {
                             var config = JSON.parse(req.responseText);
 
                             kc.authServerUrl = config['auth-server-url'];
@@ -633,6 +633,10 @@
             return promise.promise;
         }
 
+        function fileLoaded(xhr) {
+            return xhr.status == 0 && xhr.responseText && xhr.responseURL.startsWith('file:');
+        }
+
         function setToken(token, refreshToken, idToken, timeLocal) {
             if (kc.tokenTimeoutHandle) {
                 clearTimeout(kc.tokenTimeoutHandle);