AngularJS：将服务注入 HTTP 拦截器（循环依赖）

我正在尝试为我的 AngularJS 应用程序编写一个 HTTP 拦截器来处理身份验证。

这段代码可以工作，但我担心手动注入服务，因为我认为 Angular 应该自动处理这个问题：

    app.config(['$httpProvider', function ($httpProvider) {
    $httpProvider.interceptors.push(function ($location, $injector) {
        return {
            'request': function (config) {
                //injected manually to get around circular dependency problem.
                var AuthService = $injector.get('AuthService');
                console.log(AuthService);
                console.log('in request interceptor');
                if (!AuthService.isAuthenticated() && $location.path != '/login') {
                    console.log('user is not logged in.');
                    $location.path('/login');
                }
                return config;
            }
        };
    })
}]);

我开始做的事情，但遇到了循环依赖问题：

    app.config(function ($provide, $httpProvider) {
    $provide.factory('HttpInterceptor', function ($q, $location, AuthService) {
        return {
            'request': function (config) {
                console.log('in request interceptor.');
                if (!AuthService.isAuthenticated() && $location.path != '/login') {
                    console.log('user is not logged in.');
                    $location.path('/login');
                }
                return config;
            }
        };
    });

    $httpProvider.interceptors.push('HttpInterceptor');
});

我担心的另一个原因是$http 部分Angular 文档中似乎展示了一种将依赖项以“常规方式”注入 Http 拦截器的方法。请参阅“拦截器”下的代码片段：

// register the interceptor as a service
$provide.factory('myHttpInterceptor', function($q, dependency1, dependency2) {
  return {
    // optional method
    'request': function(config) {
      // do something on success
      return config || $q.when(config);
    },

    // optional method
   'requestError': function(rejection) {
      // do something on error
      if (canRecover(rejection)) {
        return responseOrNewPromise
      }
      return $q.reject(rejection);
    },



    // optional method
    'response': function(response) {
      // do something on success
      return response || $q.when(response);
    },

    // optional method
   'responseError': function(rejection) {
      // do something on error
      if (canRecover(rejection)) {
        return responseOrNewPromise
      }
      return $q.reject(rejection);
    };
  }
});

$httpProvider.interceptors.push('myHttpInterceptor');

上面的代码应该放在哪里？

我想我的问题是这样做的正确方法是什么？

谢谢，我希望我的问题足够清楚。

这就是我最终所做的

  .config(['$httpProvider', function ($httpProvider) {
        //enable cors
        $httpProvider.defaults.useXDomain = true;

        $httpProvider.interceptors.push(['$location', '$injector', '$q', function ($location, $injector, $q) {
            return {
                'request': function (config) {

                    //injected manually to get around circular dependency problem.
                    var AuthService = $injector.get('Auth');

                    if (!AuthService.isAuthenticated()) {
                        $location.path('/login');
                    } else {
                        //add session_id as a bearer token in header of all outgoing HTTP requests.
                        var currentUser = AuthService.getCurrentUser();
                        if (currentUser !== null) {
                            var sessionId = AuthService.getCurrentUser().sessionId;
                            if (sessionId) {
                                config.headers.Authorization = 'Bearer ' + sessionId;
                            }
                        }
                    }

                    //add headers
                    return config;
                },
                'responseError': function (rejection) {
                    if (rejection.status === 401) {

                        //injected manually to get around circular dependency problem.
                        var AuthService = $injector.get('Auth');

                        //if server returns 401 despite user being authenticated on app side, it means session timed out on server
                        if (AuthService.isAuthenticated()) {
                            AuthService.appLogOut();
                        }
                        $location.path('/login');
                        return $q.reject(rejection);
                    }
                }
            };
        }]);
    }]);

注：$injector.get调用应该在拦截器的方法内，如果您尝试在其他地方使用它们，您将继续在 JS 中遇到循环依赖错误。