Check if creds are present and not None

Currently, KeystoneStrategy checks whether the required credentials are
present in the creds dict but it doesn't check whether they are valid or
not.

This patch checks whether the required creds are present and not None
otherwise a MissingCredentials exception will be raised.

Note: No need for checking parameters' values types since they'll be
instances of basestring once set otherwise they'll be None.

Fixes bug 1157765

Change-Id: I664a604c3cbf2fca60a88c4d887cd9a4b678c8a5
(cherry picked from commit 855162b)

glance/common/auth.py

@@ -85,14 +85,14 @@ def check_auth_params(self):
         # Ensure that supplied credential parameters are as required
         for required in ('username', 'password', 'auth_url',
                          'strategy'):
-            if required not in self.creds:
+            if self.creds.get(required) is None:
                 raise exception.MissingCredentialError(required=required)
         if self.creds['strategy'] != 'keystone':
             raise exception.BadAuthStrategy(expected='keystone',
                                             received=self.creds['strategy'])
         # For v2.0 also check tenant is present
         if self.creds['auth_url'].rstrip('/').endswith('v2.0'):
-            if 'tenant' not in self.creds:
+            if self.creds.get("tenant") is None:
                 raise exception.MissingCredentialError(required='tenant')
 
     def authenticate(self):

glance/tests/unit/test_auth.py

@@ -145,7 +145,18 @@ def test_required_creds(self):
                 'username': 'user1',
                 'password': 'pass',
                 'auth_url': 'http://localhost/v2.0/'
-            }  # v2.0: missing tenant
+            },  # v2.0: missing tenant
+            {
+                'username': None,
+                'password': 'pass',
+                'auth_url': 'http://localhost/v2.0/'
+            },  # None parameter
+            {
+                'username': 'user1',
+                'password': 'pass',
+                'auth_url': 'http://localhost/v2.0/',
+                'tenant': None
+            }  # None tenant
         ]
         for creds in bad_creds:
             try: