feat($translateProvider): adds registerAvailableLanguagesKeys for neg…

…otiation makes it possible to define available languages keys and possible aliases to automatically determine locale.
angular-translate · Dec 18, 2013 · 6bef6bd · knalli · Dec 21, 2013 · 0x-r4bbit
1 parent 7cbfabe
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Showing 2 changed files with 109 additions and 15 deletions.
diff --git a/src/service/translate.js b/src/service/translate.js
@@ -11,6 +11,8 @@ angular.module('pascalprecht.translate').provider('$translate', ['$STORAGE_KEY',
 
   var $translationTable = {},
       $preferredLanguage,
+      $availableLanguageKeys = [],
+      $languageKeyAliases,
       $fallbackLanguage,
       $fallbackWasString,
       $uses,
@@ -44,6 +46,39 @@ angular.module('pascalprecht.translate').provider('$translate', ['$STORAGE_KEY',
     return lang;
   };
 
+  var negotiateLocale = function (preferred) {
+
+    var avail = [],
+        locale = angular.lowercase(preferred),
+        i = 0,
+        n = $availableLanguageKeys.length;
+
+    for (; i < n; i++) {
+      avail.push(angular.lowercase($availableLanguageKeys[i]));
+    }
+
+    if (avail.indexOf(locale) > -1) {
+      return locale;
+    }
+
+    if ($languageKeyAliases) {
+
+      if ($languageKeyAliases[preferred]) {
+        var alias = $languageKeyAliases[preferred];
+
+        if (avail.indexOf(angular.lowercase(alias)) > -1) {
+          return alias;
+        }
+      }
+    }
+
+    var parts = preferred.split('_');
+
+    if (parts.length > 1 && avail.indexOf(angular.lowercase(parts[0])) > 1) {
+      return parts[0];
+    }
+  };
+
   /**
    * @ngdoc function
    * @name pascalprecht.translate.$translateProvider#translations
@@ -528,8 +563,40 @@ angular.module('pascalprecht.translate').provider('$translate', ['$STORAGE_KEY',
    * @param {object=} fn Function to determine a browser's locale
    */
   this.determinePreferredLanguage = function (fn) {
-    $preferredLanguage = (fn && angular.isFunction(fn)) ? fn() : getLocale();
-    return this;
+
+    var locale = (fn && angular.isFunction(fn)) ? fn() : getLocale();
+
+    if (!$availableLanguageKeys.length) {
+      $preferredLanguage = locale;
+      return this;
+    } else {
+      $preferredLanguage = negotiateLocale(locale);
+    }
+  };
+
+  /**
+   * @ngdoc function
+   * @name pascalprecht.translate.$translateProvider#registerAvailableLanguageKeys
+   * @methodOf pascalprecht.translate.$translateProvider
+   *
+   * @description
+   * Registers a set of language keys the app will work with. Use this method in
+   * combination with
+   * {@link pascalprecht.translate.$translateProvider#determinePreferredLanguage determinePreferredLanguage}. When available languages keys are registered, angular-translate
+   * tries to find the best fitting language key depending on the browsers locale,
+   * considering your language key convention.
+   *
+   * @param {object} languageKeys Array of language keys the your app will use
+   */
+  this.registerAvailableLanguageKeys = function (languageKeys, aliases) {
+    if (languageKeys) {
+      $availableLanguageKeys = languageKeys;
+      if (aliases) {
+        $languageKeyAliases = aliases;
+      }
+      return this;
+    }
+    return $availableLanguageKeys;
   };
 
   /**

diff --git a/test/unit/service/translate.spec.js b/test/unit/service/translate.spec.js
@@ -1650,22 +1650,49 @@ describe('pascalprecht.translate', function () {
 
   describe('determineLanguage()', function () {
 
-    beforeEach(module('pascalprecht.translate', function ($translateProvider) {
-      $translateProvider.translations('en_US', {
-        FOO: 'bar'
-      });
+    describe('without locale negotiation', function () {
+      beforeEach(module('pascalprecht.translate', function ($translateProvider) {
+        $translateProvider.translations('en_US', {
+          FOO: 'bar'
+        });
 
-      $translateProvider.translations('de_DE', {
-        FOO: 'foo'
+        $translateProvider.translations('de_DE', {
+          FOO: 'foo'
+        });
+        $translateProvider.determinePreferredLanguage();
+        // mocking
+        window.navigator.lang = 'en_US';
+      }));
+
+      it('should determine browser language', function () {
+        inject(function ($translate) {
+          expect($translate('FOO')).toEqual('bar');
+        });
       });
-      $translateProvider.determinePreferredLanguage();
-      // mocking
-      window.navigator.lang = 'en_US';
-    }));
+    });
 
-    it('should determine browser language', function () {
-      inject(function ($translate) {
-        expect($translate('FOO')).toEqual('bar');
+    describe('with locale negotiation', function () {
+      beforeEach(module('pascalprecht.translate', function ($translateProvider) {
+        $translateProvider.translations('en', {
+          FOO: 'bar'
+        });
+
+        $translateProvider.translations('de', {
+          FOO: 'foo'
+        });
+        $translateProvider.registerAvailableLanguageKeys(['en', 'de'], {
+          'en_US': 'en',
+          'de_DE': 'de'
+        });
+        $translateProvider.determinePreferredLanguage();
+        // mocking
+        window.navigator.lang = 'en_US';
+      }));
+
+      it('should determine browser language', function () {
+        inject(function ($translate) {
+          expect($translate('FOO')).toEqual('bar');
+        });
       });
     });
   });