Add google-endpoints to third_party/.

third_party/google-endpoints/oauth2client/gce.py

+# Copyright 2014 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Utilities for Google Compute Engine
+
+Utilities for making it easier to use OAuth 2.0 on Google Compute Engine.
+"""
+
+import json
+import logging
+from six.moves import urllib
+
+from oauth2client._helpers import _from_bytes
+from oauth2client import util
+from oauth2client.client import HttpAccessTokenRefreshError
+from oauth2client.client import AssertionCredentials
+
+
+__author__ = 'jcgregorio@google.com (Joe Gregorio)'
+
+logger = logging.getLogger(__name__)
+
+# URI Template for the endpoint that returns access_tokens.
+META = ('http://metadata.google.internal/0.1/meta-data/service-accounts/'
+        'default/acquire{?scope}')
+
+
+class AppAssertionCredentials(AssertionCredentials):
+    """Credentials object for Compute Engine Assertion Grants
+
+    This object will allow a Compute Engine instance to identify itself to
+    Google and other OAuth 2.0 servers that can verify assertions. It can be
+    used for the purpose of accessing data stored under an account assigned to
+    the Compute Engine instance itself.
+
+    This credential does not require a flow to instantiate because it
+    represents a two legged flow, and therefore has all of the required
+    information to generate and refresh its own access tokens.
+    """
+
+    @util.positional(2)
+    def __init__(self, scope, **kwargs):
+        """Constructor for AppAssertionCredentials
+
+        Args:
+            scope: string or iterable of strings, scope(s) of the credentials
+                   being requested.
+        """
+        self.scope = util.scopes_to_string(scope)
+        self.kwargs = kwargs
+
+        # Assertion type is no longer used, but still in the
+        # parent class signature.
+        super(AppAssertionCredentials, self).__init__(None)
+
+    @classmethod
+    def from_json(cls, json_data):
+        data = json.loads(_from_bytes(json_data))
+        return AppAssertionCredentials(data['scope'])
+
+    def _refresh(self, http_request):
+        """Refreshes the access_token.
+
+        Skip all the storage hoops and just refresh using the API.
+
+        Args:
+            http_request: callable, a callable that matches the method
+                          signature of httplib2.Http.request, used to make
+                          the refresh request.
+
+        Raises:
+            HttpAccessTokenRefreshError: When the refresh fails.
+        """
+        query = '?scope=%s' % urllib.parse.quote(self.scope, '')
+        uri = META.replace('{?scope}', query)
+        response, content = http_request(uri)
+        content = _from_bytes(content)
+        if response.status == 200:
+            try:
+                d = json.loads(content)
+            except Exception as e:
+                raise HttpAccessTokenRefreshError(str(e),
+                                                  status=response.status)
+            self.access_token = d['accessToken']
+        else:
+            if response.status == 404:
+                content += (' This can occur if a VM was created'
+                            ' with no service account or scopes.')
+            raise HttpAccessTokenRefreshError(content, status=response.status)
+
+    @property
+    def serialization_data(self):
+        raise NotImplementedError(
+            'Cannot serialize credentials for GCE service accounts.')
+
+    def create_scoped_required(self):
+        return not self.scope
+
+    def create_scoped(self, scopes):
+        return AppAssertionCredentials(scopes, **self.kwargs)