jasmine-ajax - Faking Ajax responses in your Jasmine suite.

jasmine-ajax is a library that lets you define a set of fake responses for Ajax requests made by your application, specify per spec which response should be used, and keep track of the Ajax requests you make so you can make assertions about the results.

Libraries Supported

jasmine-ajax is currently compatible with jQuery. Support for other libraries planned.

Installing

Download mock-ajax.js and add it to your project. If you are using the jasmine gem, be sure the location you put mock-ajax.js is included in your src_files path in jasmine.yml. If you are using Jasmine standalone, make sure you add it to your spec runner.

Setup

Using the library in your Jasmine specs consists of four parts:

1. Defining test responses
2. Installing the mock
3. Triggering the ajax request code
4. Defining the response for each request
5. Inspecting Ajax requests and setting expectations on them

Example

Let's use a simple Foursquare venue search app to show each of these steps.

1. Defining Test Responses

After signing up for an API key and playing around with curl a bit you should have an idea of what API resources you are interested in and what sample responses look like. Once you do, you can define simple JavaScripts objects that will be used to build XMLHttpRequest objects later.

For example, if you have a response that looks like this:

{
    "meta":{
        "code":200,
        "errorType":"deprecated",
        "errorDetail":"This endpoint will stop returning groups in the future. Please use a current version, see http://bit.ly/lZx3NU."
    },
    "response":{
        "groups":[{
                "type":"nearby",
                "name":"Nearby",
                "items":[{
                        "id":"4bb9fd9f3db7b7138dbd229a",
                        "name":"Pivotal Labs",
                        "contact":{
                            "twitter":"pivotalboulder"
                        },
                        "location":{
                            "address":"1701 Pearl St.",
                            "crossStreet":"at 17th St.",
                            "city":"Boulder",
                            "state":"CO",
                            "lat":40.019461,
                            "lng":-105.273296,
                            "distance":0
                        },
                        "categories":[{
                                "id":"4bf58dd8d48988d124941735",
                                "name":"Office",
                                "pluralName":"Offices",
                                "icon":"https://foursquare.com/img/categories/building/default.png",
                                "parents":["Homes, Work, Others"
                                ],
                                "primary":true
                            }
                        ],
                        "verified":false,
                        "stats":{
                            "checkinsCount":223,
                            "usersCount":62
                        },
                        "hereNow":{
                            "count":0
                        }
                    }
                ]
            }
        ]
    }
}

Then you'd define a mock response that looks something like this:

    var TestResponses = {
      search: {
        success: {
          status: 200,
          responseText: '{"response":{"groups":[{"type":"nearby","name":"Nearby","items":[{"id":"4bb9fd9f3db7b7138dbd229a","name":"Pivotal Labs","contact":{"twitter":"pivotalboulder"},"location":{"address":"1701 Pearl St.","crossStreet":"at 17th St.","city":"Boulder","state":"CO","lat":40.019461,"lng":-105.273296,"distance":0},"categories":[{"id":"4bf58dd8d48988d124941735","name":"Office","pluralName":"Offices","icon":"https://foursquare.com/img/categories/building/default.png","parents":["Homes, Work, Others"],"primary":true}],"verified":false,"stats":{"checkinsCount":223,"usersCount":62},"hereNow":{"count":0}},{"id":"4af2eccbf964a5203ae921e3","name":"Laughing Goat Café","contact":{},"location":{"address":"1709 Pearl St.","crossStreet":"btw 16th & 17th","city":"Boulder","state":"CO","postalCode":"80302","country":"USA","lat":40.019321,"lng":-105.27311982,"distance":21},"categories":[{"id":"4bf58dd8d48988d1e0931735","name":"Coffee Shop","pluralName":"Coffee Shops","icon":"https://foursquare.com/img/categories/food/coffeeshop.png","parents":["Food"],"primary":true},{"id":"4bf58dd8d48988d1a7941735","name":"College Library","pluralName":"College Libraries","icon":"https://foursquare.com/img/categories/education/default.png","parents":["Colleges & Universities"]}],"verified":false,"stats":{"checkinsCount":1314,"usersCount":517},"hereNow":{"count":0}},{"id":"4ca777a597c8a1cdf7bc7aa5","name":"Ted\'s Montana Grill","contact":{"phone":"3034495546","formattedPhone":"(303) 449-5546","twitter":"TedMontanaGrill"},"location":{"address":"1701 Pearl St.","crossStreet":"17th and Pearl","city":"Boulder","state":"CO","postalCode":"80302","country":"USA","lat":40.019376,"lng":-105.273311,"distance":9},"categories":[{"id":"4bf58dd8d48988d1cc941735","name":"Steakhouse","pluralName":"Steakhouses","icon":"https://foursquare.com/img/categories/food/steakhouse.png","parents":["Food"],"primary":true}],"verified":true,"stats":{"checkinsCount":197,"usersCount":150},"url":"http://www.tedsmontanagrill.com/","hereNow":{"count":0}},{"id":"4d3cac5a8edf3704e894b2a5","name":"Pizzeria Locale","contact":{},"location":{"address":"1730 Pearl St","city":"Boulder","state":"CO","postalCode":"80302","country":"USA","lat":40.0193746,"lng":-105.2726744,"distance":53},"categories":[{"id":"4bf58dd8d48988d1ca941735","name":"Pizza Place","pluralName":"Pizza Places","icon":"https://foursquare.com/img/categories/food/pizza.png","parents":["Food"],"primary":true}],"verified":false,"stats":{"checkinsCount":511,"usersCount":338},"hereNow":{"count":2}},{"id":"4d012cd17c56370462a6b4f0","name":"The Pinyon","contact":{},"location":{"address":"1710 Pearl St.","city":"Boulder","state":"CO","country":"USA","lat":40.019219,"lng":-105.2730563,"distance":33},"categories":[{"id":"4bf58dd8d48988d14e941735","name":"American Restaurant","pluralName":"American Restaurants","icon":"https://foursquare.com/img/categories/food/default.png","parents":["Food"],"primary":true}],"verified":true,"stats":{"checkinsCount":163,"usersCount":98},"hereNow":{"count":1}}]}]}}'
        }
      }
    };

A good place to define this is in spec/javascripts/helpers/test_responses. You can also define failure responses, for whatever status codes the API you are working with supports.

2. Installing the mock

Install the mock using jasmine.Ajax.useMock():

beforeEach(function() {
  jasmine.Ajax.useMock();
  ...

After this, all Ajax requests will be captured by jasmine-ajax. If you want to do things like load fixtures, do it before you install the mock (see below).

3. Trigger ajax request code

Before you can specify that a request uses your test response, you must have a handle to the request itself. This means that the request is made first by the code under test and then you will set your test response (see next step).

    foursquare.search('40.019461,-105.273296', {
      onSuccess: onSuccess,
      onFailure: onFailure
    });

    request = mostRecentAjaxRequest();

The onreadystatechange event isn't fired to complete the ajax request until you set the response in the next step.

4. Set responses

Now that you've defined some test responses and installed the mock, you need to tell jasmine-ajax which response to use for a given spec. If you want to use your success response for a set of related success specs, you might use:

describe("on success", function() {
  beforeEach(function() {
    request.response(TestResponses.search.success);
  });

Now for all the specs in this example group, whenever an Ajax response is sent, it will use the TestResponses.search.success object defined in your test responses to build the XMLHttpRequest object.

5. Inspect Ajax requests

Putting it all together, you can install the mock, pass some spies as callbacks to your search object, and make expectations about the expected behavior.

describe("FoursquareVenueSearch", function() {
  var foursquare, request;
  var onSuccess, onFailure;

  beforeEach(function() {
    jasmine.Ajax.useMock();

    onSuccess = jasmine.createSpy('onSuccess');
    onFailure = jasmine.createSpy('onFailure');

    foursquare = new FoursquareVenueSearch();

    foursquare.search('40.019461,-105.273296', {
      onSuccess: onSuccess,
      onFailure: onFailure
    });

    request = mostRecentAjaxRequest();
    expect(request.url).toBe('venues/search');
    expect(request.method).toBe('POST');
    expect(request.data()).toEqual({latLng: ['40.019461, -105.273296']});
  });

  describe("on success", function() {
    beforeEach(function() {
      request.response(TestResponses.search.success);
    });

    it("calls onSuccess with an array of Locations", function() {
      expect(onSuccess).toHaveBeenCalled();

      var successArgs = onSuccess.mostRecentCall.args[0];

      expect(successArgs.length).toEqual(1);
      expect(successArgs[0]).toEqual(jasmine.any(Venue));
    });
  });
});

Loading Fixtures

Most third-party Jasmine extensions use Ajax to load HTML fixtures into the DOM. Since jasmine-ajax intercepts all Ajax calls after it is installed, you need to load your fixtures before installing the mock. If you are using jasmine-jquery, that looks like this:

beforeEach(function){
  // first load your fixtures
  loadFixtures('fixture.html');

  // then install the mock
  jasmine.Ajax.useMock();
});

Jasmine

http://github.com/pivotal/jasmine

Copyright (c) 2011 Pivotal Labs. This software is licensed under the MIT License.