Updated DB_Helper by adding firebase methods.

venv/Lib/site-packages/oauth2client/contrib/gce.py

@@ -0,0 +1,162 @@
+# 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 logging
+import warnings
+
+import httplib2
+
+from oauth2client import client
+from oauth2client.contrib import _metadata
+
+
+__author__ = 'jcgregorio@google.com (Joe Gregorio)'
+
+logger = logging.getLogger(__name__)
+
+_SCOPES_WARNING = """\
+You have requested explicit scopes to be used with a GCE service account.
+Using this argument will have no effect on the actual scopes for tokens
+requested. These scopes are set at VM instance creation time and
+can't be overridden in the request.
+"""
+
+
+class AppAssertionCredentials(client.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.
+
+    Note that :attr:`service_account_email` and :attr:`scopes`
+    will both return None until the credentials have been refreshed.
+    To check whether credentials have previously been refreshed use
+    :attr:`invalid`.
+    """
+
+    def __init__(self, email=None, *args, **kwargs):
+        """Constructor for AppAssertionCredentials
+
+        Args:
+            email: an email that specifies the service account to use.
+                   Only necessary if using custom service accounts
+                   (see https://cloud.google.com/compute/docs/access/create-enable-service-accounts-for-instances#createdefaultserviceaccount).
+        """
+        if 'scopes' in kwargs:
+            warnings.warn(_SCOPES_WARNING)
+            kwargs['scopes'] = None
+
+        # Assertion type is no longer used, but still in the
+        # parent class signature.
+        super(AppAssertionCredentials, self).__init__(None, *args, **kwargs)
+
+        self.service_account_email = email
+        self.scopes = None
+        self.invalid = True
+
+    @classmethod
+    def from_json(cls, json_data):
+        raise NotImplementedError(
+            'Cannot serialize credentials for GCE service accounts.')
+
+    def to_json(self):
+        raise NotImplementedError(
+            'Cannot serialize credentials for GCE service accounts.')
+
+    def retrieve_scopes(self, http):
+        """Retrieves the canonical list of scopes for this access token.
+
+        Overrides client.Credentials.retrieve_scopes. Fetches scopes info
+        from the metadata server.
+
+        Args:
+            http: httplib2.Http, an http object to be used to make the refresh
+                  request.
+
+        Returns:
+            A set of strings containing the canonical list of scopes.
+        """
+        self._retrieve_info(http.request)
+        return self.scopes
+
+    def _retrieve_info(self, http_request):
+        """Validates invalid service accounts by retrieving service account info.
+
+        Args:
+            http_request: callable, a callable that matches the method
+                          signature of httplib2.Http.request, used to make the
+                          request to the metadata server
+        """
+        if self.invalid:
+            info = _metadata.get_service_account_info(
+                http_request,
+                service_account=self.service_account_email or 'default')
+            self.invalid = False
+            self.service_account_email = info['email']
+            self.scopes = info['scopes']
+
+    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.
+        """
+        try:
+            self._retrieve_info(http_request)
+            self.access_token, self.token_expiry = _metadata.get_token(
+                http_request, service_account=self.service_account_email)
+        except httplib2.HttpLib2Error as e:
+            raise client.HttpAccessTokenRefreshError(str(e))
+
+    @property
+    def serialization_data(self):
+        raise NotImplementedError(
+            'Cannot serialize credentials for GCE service accounts.')
+
+    def create_scoped_required(self):
+        return False
+
+    def sign_blob(self, blob):
+        """Cryptographically sign a blob (of bytes).
+
+        This method is provided to support a common interface, but
+        the actual key used for a Google Compute Engine service account
+        is not available, so it can't be used to sign content.
+
+        Args:
+            blob: bytes, Message to be signed.
+
+        Raises:
+            NotImplementedError, always.
+        """
+        raise NotImplementedError(
+            'Compute Engine service accounts cannot sign blobs')