Adding cancellation support

lib/adapters/http.js

@@ -185,6 +185,15 @@ module.exports = function httpAdapter(config) {
       }, config.timeout);
     }
 
+    if (config.cancelToken) {
+      // Handle cancellation
+      config.cancelToken.promise.then(function onCanceled(cancel) {
+        req.abort();
+        reject(cancel);
+        aborted = true;
+      });
+    }
+
     // Send the request
     if (utils.isStream(data)) {
       data.pipe(req);

lib/adapters/xhr.js

@@ -153,6 +153,15 @@ module.exports = function xhrAdapter(config) {
       request.upload.addEventListener('progress', config.onUploadProgress);
     }
 
+    if (config.cancelToken) {
+      // Handle cancellation
+      config.cancelToken.promise.then(function onCanceled(cancel) {
+        request.abort();
+        reject(cancel);
+        // Clean up request
+        request = null;
+      });
+    }
 
     if (requestData === undefined) {
       requestData = null;

lib/axios.js

@@ -34,6 +34,10 @@ axios.create = function create(defaultConfig) {
   return createInstance(defaultConfig);
 };
 
+// Expose Cancel & CancelToken
+axios.Cancel = require('./cancel/Cancel');
+axios.CancelToken = require('./cancel/CancelToken');
+
 // Expose all/spread
 axios.all = function all(promises) {
   return Promise.all(promises);

lib/core/dispatchRequest.js

@@ -2,6 +2,16 @@
 
 var utils = require('./../utils');
 var transformData = require('./transformData');
+var Cancel = require('../cancel/Cancel');
+
+/**
+ * Throws a `Cancel` if cancellation has been requested.
+ */
+function throwIfCancellationRequested(config) {
+  if (config.cancelToken) {
+    config.cancelToken.throwIfRequested();
+  }
+}
 
 /**
  * Dispatch a request to the server using whichever adapter
@@ -11,6 +21,8 @@ var transformData = require('./transformData');
  * @returns {Promise} The Promise to be fulfilled
  */
 module.exports = function dispatchRequest(config) {
+  throwIfCancellationRequested(config);
+
   // Ensure headers exist
   config.headers = config.headers || {};
 
@@ -52,6 +64,8 @@ module.exports = function dispatchRequest(config) {
     // Wrap synchronous adapter errors and pass configuration
     .then(adapter)
     .then(function onFulfilled(response) {
+      throwIfCancellationRequested(config);
+
       // Transform response data
       response.data = transformData(
         response.data,
@@ -60,16 +74,20 @@ module.exports = function dispatchRequest(config) {
       );
 
       return response;
-    }, function onRejected(error) {
-      // Transform response data
-      if (error && error.response) {
-        error.response.data = transformData(
-          error.response.data,
-          error.response.headers,
-          config.transformResponse
-        );
+    }, function onRejected(reason) {
+      if (!(reason instanceof Cancel)) {
+        throwIfCancellationRequested(config);
+
+        // Transform response data
+        if (reason && reason.response) {
+          reason.response.data = transformData(
+            reason.response.data,
+            reason.response.headers,
+            config.transformResponse
+          );
+        }
       }
 
-      return Promise.reject(error);
+      return Promise.reject(reason);
     });
 };

test/specs/cancel.spec.js

@@ -0,0 +1,66 @@
+var Cancel = axios.Cancel;
+var CancelToken = axios.CancelToken;
+
+describe('cancel', function() {
+  beforeEach(function() {
+    jasmine.Ajax.install();
+  });
+
+  afterEach(function() {
+    jasmine.Ajax.uninstall();
+  });
+
+  describe('when called before sending request', function() {
+    it('rejects Promise with a Cancel object', function (done) {
+      var source = CancelToken.source();
+      source.cancel('Operation has been canceled.');
+      axios.get('/foo', {
+        cancelToken: source.token
+      }).catch(function (thrown) {
+        expect(thrown).toEqual(jasmine.any(Cancel));
+        expect(thrown.message).toBe('Operation has been canceled.');
+        done();
+      });
+    });
+  });
+
+  describe('when called after request has been sent', function() {
+    it('rejects Promise with a Cancel object', function (done) {
+      var source = CancelToken.source();
+      axios.get('/foo/bar', {
+        cancelToken: source.token
+      }).catch(function (thrown) {
+        expect(thrown).toEqual(jasmine.any(Cancel));
+        expect(thrown.message).toBe('Operation has been canceled.');
+        done();
+      });
+
+      getAjaxRequest().then(function (request) {
+        // call cancel() when the request has been sent, but a response has not been received
+        source.cancel('Operation has been canceled.');
+        request.respondWith({
+          status: 200,
+          responseText: 'OK'
+        });
+      });
+    });
+
+    it('calls abort on request object', function (done) {
+      var source = CancelToken.source();
+      var request;
+      axios.get('/foo/bar', {
+        cancelToken: source.token
+      }).catch(function() {
+        // jasmine-ajax sets statusText to 'abort' when request.abort() is called
+        expect(request.statusText).toBe('abort');
+        done();
+      });
+
+      getAjaxRequest().then(function (req) {
+        // call cancel() when the request has been sent, but a response has not been received
+        source.cancel();
+        request = req;
+      });
+    });
+  });
+});

test/specs/instance.spec.js

@@ -11,7 +11,14 @@ describe('instance', function () {
     var instance = axios.create();
 
     for (var prop in axios) {
-      if (['Axios', 'create', 'all', 'spread', 'default'].indexOf(prop) > -1) {
+      if ([
+        'Axios',
+        'create',
+        'Cancel',
+        'CancelToken',
+        'all',
+        'spread',
+        'default'].indexOf(prop) > -1) {
         continue;
       }
       expect(typeof instance[prop]).toBe(typeof axios[prop]);

test/unit/adapters/http.js

@@ -320,5 +320,21 @@ module.exports = {
         });
       });
     });
+  },
+
+  testCancel: function(test) {
+    var source = axios.CancelToken.source();
+    server = http.createServer(function (req, res) {
+      // call cancel() when the request has been sent, but a response has not been received
+      source.cancel('Operation has been canceled.');
+    }).listen(4444, function() {
+      axios.get('http://localhost:4444/', {
+        cancelToken: source.token
+      }).catch(function (thrown) {
+        test.ok(thrown instanceof axios.Cancel, 'Promise must be rejected with a Cancel obejct');
+        test.equal(thrown.message, 'Operation has been canceled.');
+        test.done();
+      });
+    });
   }
 };