Update getAccessToken to allow custom data

- Previously, we were only allowing `username` and `password`.

Author: ruipenso

src/providers/oauth-provider.js

@@ -107,23 +107,16 @@ function OAuthProvider() {
        * Retrieves the `access_token` and stores the `response.data` on cookies
        * using the `OAuthToken`.
        *
-       * @param {object} user - Object with `username` and `password` properties.
-       * @param {object} config - Optional configuration object sent to `POST`.
+       * @param {object} data - Request content, e.g., `username` and `password`.
+       * @param {object} options - Optional configuration.
        * @return {promise} A response promise.
        */
 
-      getAccessToken(user, options) {
-        // Check if `user` has required properties.
-        if (!user || !user.username || !user.password) {
-          throw new Error('`user` must be an object with `username` and `password` properties.');
-        }
-
-        var data = {
+      getAccessToken(data, options) {
+        data = angular.extend({
           client_id: config.clientId,
-          grant_type: 'password',
-          username: user.username,
-          password: user.password
-        };
+          grant_type: 'password'
+        }, data);
 
         if (null !== config.clientSecret) {
           data.client_secret = config.clientSecret;
@@ -132,7 +125,10 @@ function OAuthProvider() {
         data = queryString.stringify(data);
 
         options = angular.extend({
-          headers: { 'Content-Type': 'application/x-www-form-urlencoded' }
+          headers: {
+            'Authorization': undefined,
+            'Content-Type': 'application/x-www-form-urlencoded'
+          }
         }, options);
 
         return $http.post(`${config.baseUrl}${config.grantPath}`, data, options).then((response) => {

test/unit/providers/oauth-provider.spec.js

@@ -158,54 +158,6 @@ describe('OAuthProvider', function() {
         client_secret: defaults.clientSecret
       });
 
-      it('should throw an error if `user` is missing', inject(function(OAuth) {
-        try {
-          OAuth.getAccessToken();
-
-          should.fail();
-        } catch(e) {
-          e.should.be.an.instanceOf(Error);
-          e.message.should.match(/user/);
-        }
-      }));
-
-      it('should throw an error if `user` is empty', inject(function(OAuth) {
-        try {
-          OAuth.getAccessToken({});
-
-          should.fail();
-        } catch(e) {
-          e.should.be.an.instanceOf(Error);
-          e.message.should.match(/user/);
-        }
-      }));
-
-      it('should throw an error if `username` is not provided', inject(function(OAuth) {
-        try {
-          OAuth.getAccessToken({
-            password: 'foo'
-          });
-
-          should.fail();
-        } catch(e) {
-          e.should.be.an.instanceOf(Error);
-          e.message.should.match(/user/);
-        }
-      }));
-
-      it('should throw an error if `password` is not provided', inject(function(OAuth) {
-        try {
-          OAuth.getAccessToken({
-            username: 'foo'
-          });
-
-          should.fail();
-        } catch(e) {
-          e.should.be.an.instanceOf(Error);
-          e.message.should.match(/user/);
-        }
-      }));
-
       it('should call `queryString.stringify`', inject(function(OAuth) {
         sinon.spy(queryString, 'stringify');