Merge pull request #120 from justinwp/master

with MasterKey('key'):

README.mkd

@@ -558,4 +558,16 @@ with SessionToken(token):
 
 Assuming the CollectedItem 'Sword' is read-protected from the public by an ACL and is readable only by the user, SessionToken allows the user to bypass the ACL and get the 'Sword' item.
 
+Elevating Access to Master
+--------------------------
+Sometimes it is useful to only allow privileged use of the master key for specific uses. 
+
+~~~~~ {python}
+from parse_rest.connection import MasterKey
+
+with MasterKey('master key'):
+    # do privileged calls
+~~~~~
+
+
 That's it! This is a first try at a Python library for Parse, and is probably not bug-free. If you run into any issues, please get in touch -- dgrtwo@princeton.edu. Thanks!

parse_rest/connection.py

@@ -45,7 +45,19 @@ class SessionToken:
         ACCESS_KEYS.update({'session_token': self.token})
 
     def __exit__(self, type, value, traceback):
-        ACCESS_KEYS['session_token']
+        del ACCESS_KEYS['session_token']
+
+
+class MasterKey:
+    def __init__(self, master_key):
+        global ACCESS_KEYS
+        self.master_key = master_key
+
+    def __enter__(self):
+        return ACCESS_KEYS.update({'master_key': self.master_key})
+
+    def __exit__(self, type, value, traceback):
+        del ACCESS_KEYS['master_key']
 
 
 def master_key_required(func):

parse_rest/tests.py

@@ -15,7 +15,7 @@ import six
 from itertools import chain
 
 from parse_rest.core import ResourceRequestNotFound
-from parse_rest.connection import register, ParseBatcher
+from parse_rest.connection import register, ParseBatcher, SessionToken, MasterKey
 from parse_rest.datatypes import GeoPoint, Object, Function, Pointer
 from parse_rest.user import User
 from parse_rest import query
@@ -579,6 +579,34 @@ class TestPush(unittest.TestCase):
                    channels=["Mets"], where={"scores": True})
 
 
+class TestSessionToken(unittest.TestCase):
+    """
+    Test SessionToken class enter and exit.
+    """
+    def get_access_keys(self):
+        from parse_rest.connection import ACCESS_KEYS
+        return ACCESS_KEYS
+
+    def testWithSessionToken(self):
+        with SessionToken(token='asdf'):
+            self.assertIn('session_token', self.get_access_keys())
+        self.assertNotIn('session_token', self.get_access_keys())
+
+
+class TestMasterKey(unittest.TestCase):
+    """
+    Test MasterKey class enter and exit.
+    """
+    def get_access_keys(self):
+        from parse_rest.connection import ACCESS_KEYS
+        return ACCESS_KEYS
+
+    def testWithMasterKey(self):
+        with MasterKey(master_key='asdf'):
+            self.assertIn('master_key', self.get_access_keys() )
+        self.assertNotIn('master_key', self.get_access_keys() )
+
+
 def run_tests():
     """Run all tests in the parse_rest package"""
     tests = unittest.TestLoader().loadTestsFromNames(['parse_rest.tests'])