# Copyright 2016 Google LLC # # 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. """OAuth 2.0 Credentials. This module provides credentials based on OAuth 2.0 access and refresh tokens. These credentials usually access resources on behalf of a user (resource owner). Specifically, this is intended to use access tokens acquired using the `Authorization Code grant`_ and can refresh those tokens using a optional `refresh token`_. Obtaining the initial access and refresh token is outside of the scope of this module. Consult `rfc6749 section 4.1`_ for complete details on the Authorization Code grant flow. .. _Authorization Code grant: https://tools.ietf.org/html/rfc6749#section-1.3.1 .. _refresh token: https://tools.ietf.org/html/rfc6749#section-6 .. _rfc6749 section 4.1: https://tools.ietf.org/html/rfc6749#section-4.1 """ from datetime import datetime import io import json import six from google.auth import _cloud_sdk from google.auth import _helpers from google.auth import credentials from google.auth import exceptions from google.oauth2 import _client # The Google OAuth 2.0 token endpoint. Used for authorized user credentials. _GOOGLE_OAUTH2_TOKEN_ENDPOINT = "https://oauth2.googleapis.com/token" class Credentials(credentials.ReadOnlyScoped, credentials.CredentialsWithQuotaProject): """Credentials using OAuth 2.0 access and refresh tokens. The credentials are considered immutable. If you want to modify the quota project, use :meth:`with_quota_project` or :: credentials = credentials.with_quota_project('myproject-123) """ def __init__( self, token, refresh_token=None, id_token=None, token_uri=None, client_id=None, client_secret=None, scopes=None, quota_project_id=None, expiry=None, ): """ Args: token (Optional(str)): The OAuth 2.0 access token. Can be None if refresh information is provided. refresh_token (str): The OAuth 2.0 refresh token. If specified, credentials can be refreshed. id_token (str): The Open ID Connect ID Token. token_uri (str): The OAuth 2.0 authorization server's token endpoint URI. Must be specified for refresh, can be left as None if the token can not be refreshed. client_id (str): The OAuth 2.0 client ID. Must be specified for refresh, can be left as None if the token can not be refreshed. client_secret(str): The OAuth 2.0 client secret. Must be specified for refresh, can be left as None if the token can not be refreshed. scopes (Sequence[str]): The scopes used to obtain authorization. This parameter is used by :meth:`has_scopes`. OAuth 2.0 credentials can not request additional scopes after authorization. The scopes must be derivable from the refresh token if refresh information is provided (e.g. The refresh token scopes are a superset of this or contain a wild card scope like 'https://www.googleapis.com/auth/any-api'). quota_project_id (Optional[str]): The project ID used for quota and billing. This project may be different from the project used to create the credentials. """ super(Credentials, self).__init__() self.token = token self.expiry = expiry self._refresh_token = refresh_token self._id_token = id_token self._scopes = scopes self._token_uri = token_uri self._client_id = client_id self._client_secret = client_secret self._quota_project_id = quota_project_id def __getstate__(self): """A __getstate__ method must exist for the __setstate__ to be called This is identical to the default implementation. See https://docs.python.org/3.7/library/pickle.html#object.__setstate__ """ return self.__dict__ def __setstate__(self, d): """Credentials pickled with older versions of the class do not have all the attributes.""" self.token = d.get("token") self.expiry = d.get("expiry") self._refresh_token = d.get("_refresh_token") self._id_token = d.get("_id_token") self._scopes = d.get("_scopes") self._token_uri = d.get("_token_uri") self._client_id = d.get("_client_id") self._client_secret = d.get("_client_secret") self._quota_project_id = d.get("_quota_project_id") @property def refresh_token(self): """Optional[str]: The OAuth 2.0 refresh token.""" return self._refresh_token @property def scopes(self): """Optional[str]: The OAuth 2.0 permission scopes.""" return self._scopes @property def token_uri(self): """Optional[str]: The OAuth 2.0 authorization server's token endpoint URI.""" return self._token_uri @property def id_token(self): """Optional[str]: The Open ID Connect ID Token. Depending on the authorization server and the scopes requested, this may be populated when credentials are obtained and updated when :meth:`refresh` is called. This token is a JWT. It can be verified and decoded using :func:`google.oauth2.id_token.verify_oauth2_token`. """ return self._id_token @property def client_id(self): """Optional[str]: The OAuth 2.0 client ID.""" return self._client_id @property def client_secret(self): """Optional[str]: The OAuth 2.0 client secret.""" return self._client_secret @property def requires_scopes(self): """False: OAuth 2.0 credentials have their scopes set when the initial token is requested and can not be changed.""" return False @_helpers.copy_docstring(credentials.CredentialsWithQuotaProject) def with_quota_project(self, quota_project_id): return self.__class__( self.token, refresh_token=self.refresh_token, id_token=self.id_token, token_uri=self.token_uri, client_id=self.client_id, client_secret=self.client_secret, scopes=self.scopes, quota_project_id=quota_project_id, ) @_helpers.copy_docstring(credentials.Credentials) def refresh(self, request): if ( self._refresh_token is None or self._token_uri is None or self._client_id is None or self._client_secret is None ): raise exceptions.RefreshError( "The credentials do not contain the necessary fields need to " "refresh the access token. You must specify refresh_token, " "token_uri, client_id, and client_secret." ) access_token, refresh_token, expiry, grant_response = _client.refresh_grant( request, self._token_uri, self._refresh_token, self._client_id, self._client_secret, self._scopes, ) self.token = access_token self.expiry = expiry self._refresh_token = refresh_token self._id_token = grant_response.get("id_token") if self._scopes and "scopes" in grant_response: requested_scopes = frozenset(self._scopes) granted_scopes = frozenset(grant_response["scopes"].split()) scopes_requested_but_not_granted = requested_scopes - granted_scopes if scopes_requested_but_not_granted: raise exceptions.RefreshError( "Not all requested scopes were granted by the " "authorization server, missing scopes {}.".format( ", ".join(scopes_requested_but_not_granted) ) ) @classmethod def from_authorized_user_info(cls, info, scopes=None): """Creates a Credentials instance from parsed authorized user info. Args: info (Mapping[str, str]): The authorized user info in Google format. scopes (Sequence[str]): Optional list of scopes to include in the credentials. Returns: google.oauth2.credentials.Credentials: The constructed credentials. Raises: ValueError: If the info is not in the expected format. """ keys_needed = set(("refresh_token", "client_id", "client_secret")) missing = keys_needed.difference(six.iterkeys(info)) if missing: raise ValueError( "Authorized user info was not in the expected format, missing " "fields {}.".format(", ".join(missing)) ) # access token expiry (datetime obj); auto-expire if not saved expiry = info.get("expiry") if expiry: expiry = datetime.strptime( expiry.rstrip("Z").split(".")[0], "%Y-%m-%dT%H:%M:%S" ) else: expiry = _helpers.utcnow() - _helpers.CLOCK_SKEW # process scopes, which needs to be a seq if scopes is None and "scopes" in info: scopes = info.get("scopes") if isinstance(scopes, str): scopes = scopes.split(" ") return cls( token=info.get("token"), refresh_token=info.get("refresh_token"), token_uri=_GOOGLE_OAUTH2_TOKEN_ENDPOINT, # always overrides scopes=scopes, client_id=info.get("client_id"), client_secret=info.get("client_secret"), quota_project_id=info.get("quota_project_id"), # may not exist expiry=expiry, ) @classmethod def from_authorized_user_file(cls, filename, scopes=None): """Creates a Credentials instance from an authorized user json file. Args: filename (str): The path to the authorized user json file. scopes (Sequence[str]): Optional list of scopes to include in the credentials. Returns: google.oauth2.credentials.Credentials: The constructed credentials. Raises: ValueError: If the file is not in the expected format. """ with io.open(filename, "r", encoding="utf-8") as json_file: data = json.load(json_file) return cls.from_authorized_user_info(data, scopes) def to_json(self, strip=None): """Utility function that creates a JSON representation of a Credentials object. Args: strip (Sequence[str]): Optional list of members to exclude from the generated JSON. Returns: str: A JSON representation of this instance. When converted into a dictionary, it can be passed to from_authorized_user_info() to create a new credential instance. """ prep = { "token": self.token, "refresh_token": self.refresh_token, "token_uri": self.token_uri, "client_id": self.client_id, "client_secret": self.client_secret, "scopes": self.scopes, } if self.expiry: # flatten expiry timestamp prep["expiry"] = self.expiry.isoformat() + "Z" # Remove empty entries (those which are None) prep = {k: v for k, v in prep.items() if v is not None} # Remove entries that explicitely need to be removed if strip is not None: prep = {k: v for k, v in prep.items() if k not in strip} return json.dumps(prep) class UserAccessTokenCredentials(credentials.CredentialsWithQuotaProject): """Access token credentials for user account. Obtain the access token for a given user account or the current active user account with the ``gcloud auth print-access-token`` command. Args: account (Optional[str]): Account to get the access token for. If not specified, the current active account will be used. quota_project_id (Optional[str]): The project ID used for quota and billing. """ def __init__(self, account=None, quota_project_id=None): super(UserAccessTokenCredentials, self).__init__() self._account = account self._quota_project_id = quota_project_id def with_account(self, account): """Create a new instance with the given account. Args: account (str): Account to get the access token for. Returns: google.oauth2.credentials.UserAccessTokenCredentials: The created credentials with the given account. """ return self.__class__(account=account, quota_project_id=self._quota_project_id) @_helpers.copy_docstring(credentials.CredentialsWithQuotaProject) def with_quota_project(self, quota_project_id): return self.__class__(account=self._account, quota_project_id=quota_project_id) def refresh(self, request): """Refreshes the access token. Args: request (google.auth.transport.Request): This argument is required by the base class interface but not used in this implementation, so just set it to `None`. Raises: google.auth.exceptions.UserAccessTokenError: If the access token refresh failed. """ self.token = _cloud_sdk.get_auth_access_token(self._account) @_helpers.copy_docstring(credentials.Credentials) def before_request(self, request, method, url, headers): self.refresh(request) self.apply(headers)