從angular.js中的$ resource看不到數據

Question

我有一個非常奇怪的問題，我們正在構建一個角度應用程序。每當我從下面定義的資源（我可以構建的最簡單的例子）中加載一些數據時，我會返回一些數據以供我用於數據綁定（例如，ng-repeat ='message in message'或者{{message.id}} ）但是我永遠不能通過將它作爲一個數組或對象（取決於我使用get（{id：myId}）或query（））來從javascript讀取它。

對它進行迭代只會給我諸如$ get，$ query，$ save等的密鑰......但是沒有實際的數據。

app.factory('Message', ['$resource', function($resource) { 
    return $resource('MY_URL/messages/:id', {id: '@id'}); 
}]); 

app.service('messageService', ['$rootScope', 'Message', function($rootScope, Message) { 
    var messages = Message.query(); 
    var selectedMessage = null; 

    var service = {}; 

    service.get = function(id) { 
        // Problem A (see below for details) 
     if (arguments.length === 1) return Message.get({id: id}); 
     else return messages; 
    }; 

var MenuCtrl = function($scope, Project, messageService, otherService) { 
    $scope.projects = Project.query(); 
    $scope.messages = messageService.get(); 

    // Problem B (details below) 
}; 

在問題的我希望能夠返回一個單一的元素形成已經被取出的集合，但我需要一些方法來處理前的數據準備好所發生的呼叫。

在問題B我想處理一些提取的數據並將結果傳遞給「otherService」，但是我需要一種方法來延遲這種情況，直到數據準備就緒。

Answer 1

我只看到這個問題出現在單元測試中，解決它的方法是通過「沖洗」模擬$ httpBackend。

按照API docs：

The $httpBackend used in production, always responds to requests with responses asynchronously. If we preserved this behavior in unit testing, we'd have to create async unit tests, which are hard to write, follow and maintain. At the same time the testing mock, can't respond synchronously because that would change the execution of the code under test. For this reason the mock $httpBackend has a flush() method, which allows the test to explicitly flush pending requests and thus preserving the async api of the backend, while allowing the test to execute synchronously.

下面是一些上下文的示例：

// define a resource within a service 
angular.module('app.services', ['ngResource']) 
    .factory('Message', function ($resource) { 
    var url = ... 
     , params = ... 
     , actions = ...; 

    return $resource(url, params, actions); 
    } 

// Query the resource in a controller 
function MessagesCtrl ($scope, $routeParams, Message) { 
    $scope.messages = Message.query(); 
} 

// unit test with a mocked backend 
describe('MessagesCtrl', function() { 
    var scope, ctrl, $httpBackend, messages; 

    beforeEach(inject(function (_$httpBackend_, $rootScope, $controller) { 
    $httpBackend = _$httpBackend_; 
    scope = $rootScope.$new(); 

    messages = [ 
     { 
     id: '1', 
     text: 'foo', 
     }, { 
     id: '2', 
     text: 'foo', 
     } 
    ] 

    $httpBackend.expectGET('/api/messages').respond(messages); 
    ctrl = $controller('MessagesCtrl', {$scope: scope}); 
    })); 

    it('should get a list of messages', function() { 

    // THE NEXT LINE WILL SOLVE THE PROBLEM 
    $httpBackend.flush(); 

    expect(scope.message).toEqualData(message); 
    }); 
});