angularjs:如何在路由更改之前进行身份验证

更新

随着angularFire的发展,现在大部分已经过时了.查看此模块以获取更新版本:https: //github.com/firebase/angularFire-seed/blob/master/app/js/module.simpleLoginTools.js

它装饰ng-cloak使用简单的登录,并提供一些优化的帮助方法以及使用最新版本.

老邮政

身份验证需要往返服务器.在SPA中,您通常不会在正常使用期间重新加载页面,因此在大多数情况下这实际上是多余的.

然而,通过对Angular的适度理解来解决并不困难.事实上,我教这个确切的场景作为在最近的研讨会上编写指令的一个例子.这是我使用的要点,这是一个使用要点的示例应用程序.

请注意,如果您尝试克隆GitHub存储库,则需要获取该特定标记(git checkout step3),因为课程是按步骤教授的.

为了符合SO格式,这里是要点的内容.首先是指令:

angular.module('waitForAuth', [])

/**
 * A service that returns a promise object, which is resolved once angularFireAuth
 * is initialized (i.e. it returns login, logout, or error)
 */
.service('waitForAuth', function($rootScope, $q, $timeout) {
    var def = $q.defer(), subs = [];
    subs.push($rootScope.$on('angularFireAuth:login', fn));
    subs.push($rootScope.$on('angularFireAuth:logout', fn));
    subs.push($rootScope.$on('angularFireAuth:error', fn));
    function fn() {
       for(var i=0; i < subs.length; i++) { subs[i](); }
       $timeout(function() {
           // force $scope.$apply to be re-run after login resolves
           def.resolve();
       });
    }
    return def.promise;
})

/**
 * A directive that hides the element from view until waitForAuth resolves
 */
.directive('ngCloakAuth', function(waitForAuth) {
   return {
       restrict: 'A',
       compile: function(el) {
           console.log('waiting');
           el.addClass('hide');
           waitForAuth.then(function() {
               el.removeClass('hide');
           })
       }
   }
})

/**
 * A directive that shows elements only when the given authentication state is in effect
 */
.directive('ngShowAuth', function($rootScope) {
    var loginState;
    return {
        restrict: 'A',
        compile: function(el, attr) {
            var expState = attr.ngShowAuth;
            function fn(newState) {
                loginState = newState;
                el.toggleClass('hide', loginState !== expState );
            }
            fn(null);
            $rootScope.$on("angularFireAuth:login",  function() { fn('login') });
            $rootScope.$on("angularFireAuth:logout", function() { fn('logout') });
            $rootScope.$on("angularFireAuth:error",  function() { fn('error') });
        }
    }
});

以及一些示例用法:

<style>
  .hide { display: none; }
</style>

<script>
  // include the waitForAuth module as a dependency
  angular.module('myApp', ['waitForAuth'])

  // you can use waitForAuth directly from your scripts
  .controller('myController', function(waitForAuth) {
     waitForAuth.then(function() {
         /* do something after auth completes */
     })
  })
</script>

<!-- and you can use the directives in your views -->
<div ng-cloak-auth>Authentication has resolved.</div>

<div ng-show-auth="login">{{user.id}} is logged in</div>

<div ng-show-auth="logout">Logged out</div>

<div ng-show-auth="error">An error occurred during authentication</div>