feat($http): add support for aborting via timeout promises

If the timeout argument is a promise, abort the request when it is resolved.
Implemented by adding support to $httpBackend service and $httpBackend mock
service.

This api can also be used to explicitly abort requests while keeping the
communication between the deffered and promise unidirectional.

Closes #1159

4 files changed, 42 insertions, 21 deletions

diff --git a/src/ng/http.js b/src/ng/http.js
index 708a0650..fbdc89a5 100644
--- a/src/ng/http.js
+++ b/src/ng/http.js
@@ -548,7 +548,8 @@ function $HttpProvider() {
      *      GET request, otherwise if a cache instance built with
      *      {@link ng.$cacheFactory $cacheFactory}, this cache will be used for
      *      caching.
-     *    - **timeout** – `{number}` – timeout in milliseconds.
+     *    - **timeout** – `{number|Promise}` – timeout in milliseconds, or {@link ng.$q promise}
+     *      that should abort the request when resolved.
      *    - **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.
@@ -927,7 +928,7 @@ function $HttpProvider() {
         }
 
         resolvePromise(response, status, headersString);
-        $rootScope.$apply();
+        if (!$rootScope.$$phase) $rootScope.$apply();
       }
 
 
diff --git a/src/ng/httpBackend.js b/src/ng/httpBackend.js
index 69ac5976..ed8404f9 100644
--- a/src/ng/httpBackend.js
+++ b/src/ng/httpBackend.js
@@ -107,20 +107,25 @@ function createHttpBackend($browser, XHR, $browserDefer, callbacks, rawDocument,
     }
 
     if (timeout > 0) {
-      var timeoutId = $browserDefer(function() {
-        status = -1;
-        jsonpDone && jsonpDone();
-        xhr && xhr.abort();
-      }, timeout);
+      var timeoutId = $browserDefer(timeoutRequest, timeout);
+    } else if (timeout && timeout.then) {
+      timeout.then(timeoutRequest);
     }
 
 
+    function timeoutRequest() {
+      status = -1;
+      jsonpDone && jsonpDone();
+      xhr && xhr.abort();
+    }
+
     function completeRequest(callback, status, response, headersString) {
       // URL_MATCH is defined in src/service/location.js
       var protocol = (url.match(SERVER_MATCH) || ['', locationProtocol])[1];
 
-      // cancel timeout
+      // cancel timeout and subsequent timeout promise resolution
       timeoutId && $browserDefer.cancel(timeoutId);
+      jsonpDone = xhr = null;
 
       // fix status code for file protocol (it's always 0)
       status = (protocol == 'file') ? (response ? 200 : 404) : status;
diff --git a/src/ngMock/angular-mocks.js b/src/ngMock/angular-mocks.js
index 07673802..be71e326 100644
--- a/src/ngMock/angular-mocks.js
+++ b/src/ngMock/angular-mocks.js
@@ -937,7 +937,7 @@ function createHttpBackendMock($rootScope, $delegate, $browser) {
   }
 
   // TODO(vojta): change params to: method, url, data, headers, callback
-  function $httpBackend(method, url, data, callback, headers) {
+  function $httpBackend(method, url, data, callback, headers, timeout) {
     var xhr = new MockXhr(),
         expectation = expectations[0],
         wasExpected = false;
@@ -948,6 +948,28 @@ function createHttpBackendMock($rootScope, $delegate, $browser) {
           : angular.toJson(data);
     }
 
+    function wrapResponse(wrapped) {
+      if (!$browser && timeout && timeout.then) timeout.then(handleTimeout);
+
+      return handleResponse;
+
+      function handleResponse() {
+        var response = wrapped.response(method, url, data, headers);
+        xhr.$$respHeaders = response[2];
+        callback(response[0], response[1], xhr.getAllResponseHeaders());
+      }
+
+      function handleTimeout() {
+        for (var i = 0, ii = responses.length; i < ii; i++) {
+          if (responses[i] === handleResponse) {
+            responses.splice(i, 1);
+            callback(-1, undefined, '');
+            break;
+          }
+        }
+      }
+    }
+
     if (expectation && expectation.match(method, url)) {
       if (!expectation.matchData(data))
         throw Error('Expected ' + expectation + ' with different data\n' +
@@ -961,11 +983,7 @@ function createHttpBackendMock($rootScope, $delegate, $browser) {
       expectations.shift();
 
       if (expectation.response) {
-        responses.push(function() {
-          var response = expectation.response(method, url, data, headers);
-          xhr.$$respHeaders = response[2];
-          callback(response[0], response[1], xhr.getAllResponseHeaders());
-        });
+        responses.push(wrapResponse(expectation));
         return;
       }
       wasExpected = true;
@@ -976,13 +994,9 @@ function createHttpBackendMock($rootScope, $delegate, $browser) {
       if (definition.match(method, url, data, headers || {})) {
         if (definition.response) {
           // if $browser specified, we do auto flush all requests
-          ($browser ? $browser.defer : responsesPush)(function() {
-            var response = definition.response(method, url, data, headers);
-            xhr.$$respHeaders = response[2];
-            callback(response[0], response[1], xhr.getAllResponseHeaders());
-          });
+          ($browser ? $browser.defer : responsesPush)(wrapResponse(definition));
         } else if (definition.passThrough) {
-          $delegate(method, url, data, callback, headers);
+          $delegate(method, url, data, callback, headers, timeout);
         } else throw Error('No response defined !');
         return;
       }
diff --git a/src/ngResource/resource.js b/src/ngResource/resource.js
index c165ffab..59ac3b3a 100644
--- a/src/ngResource/resource.js
+++ b/src/ngResource/resource.js
@@ -85,7 +85,8 @@
  *     GET request, otherwise if a cache instance built with
  *     {@link ng.$cacheFactory $cacheFactory}, this cache will be used for
  *     caching.
- *   - **`timeout`** – `{number}` – timeout in milliseconds.
+ *   - **`timeout`** – `{number|Promise}` – timeout in milliseconds, or {@link ng.$q promise} that
+ *     should abort the request when resolved.
  *   - **`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.