GUAC-1345: Do not attempt to retrieve translation files for languages which are not explicitly listed as available by the REST API.

guacamole/src/main/webapp/app/locale/services/translationLoader.js

@@ -32,6 +32,7 @@ angular.module('locale').factory('translationLoader', ['$injector', function tra
     var $http           = $injector.get('$http');
     var $q              = $injector.get('$q');
     var cacheService    = $injector.get('cacheService');
+    var languageService = $injector.get('languageService');
 
     /**
      * Satisfies a translation request for the given key by searching for the
@@ -62,6 +63,28 @@ angular.module('locale').factory('translationLoader', ['$injector', function tra
             return;
         }
 
+        /**
+         * Continues trying possible translation files until no possibilities
+         * exist.
+         *
+         * @private
+         */
+        var tryNextTranslation = function tryNextTranslation() {
+            satisfyTranslation(deferred, requestedKey, remainingKeys);
+        };
+
+        // Retrieve list of supported languages
+        languageService.getLanguages()
+
+        // Attempt to retrieve translation if language is supported
+        .success(function retrievedLanguages(languages) {
+
+            // Skip retrieval if language is not supported
+            if (!(currentKey in languages)) {
+                tryNextTranslation();
+                return;
+            }
+
             // Attempt to retrieve language
             $http({
                 cache   : cacheService.languages,
@@ -74,10 +97,14 @@ angular.module('locale').factory('translationLoader', ['$injector', function tra
                 deferred.resolve(translation);
             })
 
-        // Retry with remaining languages if translation file could not be retrieved
+            // Retry with remaining languages if translation file could not be
-        .error(function translationFileUnretrievable() {
+            // retrieved
-            satisfyTranslation(deferred, requestedKey, remainingKeys);
+            .error(tryNextTranslation);
-        });
+
+        })
+
+        // Retry with remaining languages if translation does not exist
+        .error(tryNextTranslation);
 
     };