Add function for retrieving user permissions

.travis.yml

@@ -16,3 +16,4 @@ env:
     global:
         - FACEBOOK_APP_ID=198798870326423
         - FACEBOOK_SECRET=2db4d76fe8a336cf292470c20a5a5684
+        - FACEBOOK_USER_ID=12345

docs/api.rst

@@ -271,3 +271,22 @@ Deletes the object with the given ID from the graph.
 .. code-block:: python
 
     graph.delete_object(id='post_id')
+
+get_permissions
+^^^^^^^^^^^^^
+
+https://developers.facebook.com/docs/graph-api/reference/user/permissions/
+
+Returns the permissions granted to the app by the user with the given ID as a
+``dict``.
+
+**Parameters**
+
+* ``user_id`` - A ``string`` or an ``int`` that is a unique ID for a user.
+
+**Example**
+
+.. code-block:: python
+
+    permissions = graph.get_permissions(user_id=12345)
+    print(permissions["public_profile"])

facebook/__init__.py

@@ -102,6 +102,14 @@ def __init__(self, access_token=None, timeout=None, version=None,
         else:
             self.version = "v" + default_version
 
+    def get_permissions(self, user_id, **args):
+        """Fetches the permissions object from the graph."""
+        response = self.request(
+            self.version + "/" + str(user_id) + "/permissions")["data"]
+        result = dict((x["permission"], x["status"] == "granted")
+                      for x in response)
+        return result
+
     def get_object(self, id, **args):
         """Fetches the given object from the graph."""
         return self.request("{0}/{1}".format(self.version, id), args)
@@ -235,7 +243,7 @@ def request(
             # or it does not need `access_token`.
             if post_args and "access_token" not in post_args:
                 post_args["access_token"] = self.access_token
-            elif "access_token" not in args:
+            elif args and "access_token" not in args:
                 args["access_token"] = self.access_token
 
         try:

test/test_facebook.py

@@ -30,9 +30,11 @@ def setUp(self):
         try:
             self.app_id = os.environ["FACEBOOK_APP_ID"]
             self.secret = os.environ["FACEBOOK_SECRET"]
+            self.user_id = os.environ["FACEBOOK_USER_ID"]
         except KeyError:
-            raise Exception("FACEBOOK_APP_ID and FACEBOOK_SECRET "
-                            "must be set as environmental variables.")
+            raise Exception("FACEBOOK_APP_ID, FACEBOOK_SECRET, and "
+                            "FACEBOOK_USER_ID must be set as "
+                            "environmental variables.")
 
     def assert_raises_multi_regex(
             self, expected_exception, expected_regexp, callable_obj=None,
@@ -197,5 +199,29 @@ def test_parse_signed_request_when_correct(self):
         self.assertTrue('algorithm' in result)
 
 
+class TestGetUserPermissions(FacebookTestCase):
+    """
+    Test if user permissions are retrieved correctly.
+
+    Note that this only tests if the returned JSON object exists and is
+    structured as expected, not whether any specific scope is included
+    (other than the default `public_profile` scope).
+
+    """
+    @unittest.skip('test cannot be run without a valid user ID')
+    def test_get_user_permissions_node(self):
+        token = facebook.GraphAPI().get_app_access_token(
+            self.app_id, self.secret)
+        permissions = facebook.GraphAPI(token).get_permissions(self.user_id)
+        assert permissions is not None
+        assert permissions["public_profile"] is True
+
+    def test_get_user_permissions_nonexistant_user(self):
+        token = facebook.GraphAPI().get_app_access_token(
+            self.app_id, self.secret)
+        with self.assertRaises(facebook.GraphAPIError):
+            facebook.GraphAPI(token).get_permissions(1)
+
+
 if __name__ == '__main__':
     unittest.main()