feat($http): support reponseType

Closes angular#1013

Author: vojtajina

src/ng/http.js

@@ -381,6 +381,8 @@ function $HttpProvider() {
      *    - **withCredentials** - `{boolean}` - whether to to set the `withCredentials` flag on the
      *      XHR object. See {@link https://developer.mozilla.org/en/http_access_control#section_5
      *      requests with credentials} for more information.
+     *    - **responseType** - `{string}` - see {@link
+     *      https://developer.mozilla.org/en-US/docs/DOM/XMLHttpRequest#responseType requestType}.
      *
      * @returns {HttpPromise} Returns a {@link ng.$q promise} object with the
      *   standard `then` method and two http specific methods: `success` and `error`. The `then`
@@ -697,7 +699,7 @@ function $HttpProvider() {
       // if we won't have the response in cache, send the request to the backend
       if (!cachedResp) {
         $httpBackend(config.method, url, reqData, done, reqHeaders, config.timeout,
-            config.withCredentials);
+            config.withCredentials, config.responseType);
       }
 
       return promise;

src/ng/httpBackend.js

@@ -32,7 +32,7 @@ function $HttpBackendProvider() {
 
 function createHttpBackend($browser, XHR, $browserDefer, callbacks, rawDocument, locationProtocol) {
   // TODO(vojta): fix the signature
-  return function(method, url, post, callback, headers, timeout, withCredentials) {
+  return function(method, url, post, callback, headers, timeout, withCredentials, responseType) {
     $browser.$$incOutstandingRequestCount();
     url = url || $browser.url();
 
@@ -65,15 +65,19 @@ function createHttpBackend($browser, XHR, $browserDefer, callbacks, rawDocument,
       // always async
       xhr.onreadystatechange = function() {
         if (xhr.readyState == 4) {
-          completeRequest(
-              callback, status || xhr.status, xhr.responseText, xhr.getAllResponseHeaders());
+          completeRequest(callback, status || xhr.status, xhr.response || xhr.responseText,
+                          xhr.getAllResponseHeaders());
         }
       };
 
       if (withCredentials) {
         xhr.withCredentials = true;
       }
 
+      if (responseType) {
+        xhr.responseType = responseType;
+      }
+
       xhr.send(post || '');
 
       if (timeout > 0) {

test/ng/httpBackendSpec.js

@@ -135,6 +135,24 @@ describe('$httpBackend', function() {
   });
 
 
+  it('should set responseType and return xhr.response', function() {
+    $backend('GET', '/whatever', null, callback, {}, null, null, 'blob');
+
+    var xhrInstance = MockXhr.$$lastInstance;
+    expect(xhrInstance.responseType).toBe('blob');
+
+    callback.andCallFake(function(status, response) {
+      expect(response).toBe(xhrInstance.response);
+    });
+
+    xhrInstance.response = {some: 'object'};
+    xhrInstance.readyState = 4;
+    xhrInstance.onreadystatechange();
+
+    expect(callback).toHaveBeenCalledOnce();
+  });
+
+
   describe('JSONP', function() {
 
     var SCRIPT_URL = /([^\?]*)\?cb=angular\.callbacks\.(.*)/;

test/ng/httpSpec.js

@@ -959,20 +959,23 @@ describe('$http', function() {
   });
 
 
-  it('should pass timeout and withCredentials', function() {
+  it('should pass timeout, withCredentials and responseType', function() {
     var $httpBackend = jasmine.createSpy('$httpBackend');
 
-    $httpBackend.andCallFake(function(m, u, d, c, h, timeout, withCredentials) {
+    $httpBackend.andCallFake(function(m, u, d, c, h, timeout, withCredentials, responseType) {
       expect(timeout).toBe(12345);
       expect(withCredentials).toBe(true);
+      expect(responseType).toBe('json');
     });
 
     module(function($provide) {
       $provide.value('$httpBackend', $httpBackend);
     });
 
     inject(function($http) {
-      $http({method: 'GET', url: 'some.html', timeout: 12345, withCredentials: true});
+      $http({
+        method: 'GET', url: 'some.html', timeout: 12345, withCredentials: true, responseType: 'json'
+      });
       expect($httpBackend).toHaveBeenCalledOnce();
     });