google/oauth2/_client.py - platform/external/python/google-auth-library-python - Git at Google

 # Copyright 2016 Google Inc.
 #
 # 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 client.

 This is a client for interacting with an OAuth 2.0 authorization server's
 token endpoint.

 For more information about the token endpoint, see
 `Section 3.1 of rfc6749`_

 .. _Section 3.1 of rfc6749: https://tools.ietf.org/html/rfc6749#section-3.2
 """

 import datetime
 import json

 import six
 from six.moves import http_client
 from six.moves import urllib

 from google.auth import _helpers
 from google.auth import exceptions
 from google.auth import jwt

 _URLENCODED_CONTENT_TYPE = 'application/x-www-form-urlencoded'
 _JWT_GRANT_TYPE = 'urn:ietf:params:oauth:grant-type:jwt-bearer'
 _REFRESH_GRANT_TYPE = 'refresh_token'


 def _handle_error_response(response_body):
     """"Translates an error response into an exception.

     Args:
         response_body (str): The decoded response data.

     Raises:
         google.auth.exceptions.RefreshError
     """
     try:
         error_data = json.loads(response_body)
         error_details = '{}: {}'.format(
             error_data['error'],
             error_data.get('error_description'))
     # If no details could be extracted, use the response data.
     except (KeyError, ValueError):
         error_details = response_body

     raise exceptions.RefreshError(
         error_details, response_body)


 def _parse_expiry(response_data):
     """Parses the expiry field from a response into a datetime.

     Args:
         response_data (Mapping): The JSON-parsed response data.

     Returns:
         Optional[datetime]: The expiration or ``None`` if no expiration was
             specified.
     """
     expires_in = response_data.get('expires_in', None)

     if expires_in is not None:
         return _helpers.utcnow() + datetime.timedelta(
             seconds=expires_in)
     else:
         return None


 def _token_endpoint_request(request, token_uri, body):
     """Makes a request to the OAuth 2.0 authorization server's token endpoint.

     Args:
         request (google.auth.transport.Request): A callable used to make
             HTTP requests.
         token_uri (str): The OAuth 2.0 authorizations server's token endpoint
             URI.
         body (Mapping[str, str]): The parameters to send in the request body.

     Returns:
         Mapping[str, str]: The JSON-decoded response data.

     Raises:
         google.auth.exceptions.RefreshError: If the token endpoint returned
             an error.
     """
     body = urllib.parse.urlencode(body)
     headers = {
         'content-type': _URLENCODED_CONTENT_TYPE,
     }

     retry = 0
     # retry to fetch token for maximum of two times if any internal failure
     # occurs.
     while True:
         response = request(
             method='POST', url=token_uri, headers=headers, body=body)
         response_body = response.data.decode('utf-8')

         if response.status == http_client.OK:
             break
         else:
             error_desc = json.loads(
                 response_body).get('error_description') or ''
             if error_desc == 'internal_failure' and retry < 1:
                 retry += 1
                 continue
             _handle_error_response(response_body)

     response_data = json.loads(response_body)

     return response_data


 def jwt_grant(request, token_uri, assertion):
     """Implements the JWT Profile for OAuth 2.0 Authorization Grants.

     For more details, see `rfc7523 section 4`_.

     Args:
         request (google.auth.transport.Request): A callable used to make
             HTTP requests.
         token_uri (str): The OAuth 2.0 authorizations server's token endpoint
             URI.
         assertion (str): The OAuth 2.0 assertion.

     Returns:
         Tuple[str, Optional[datetime], Mapping[str, str]]: The access token,
             expiration, and additional data returned by the token endpoint.

     Raises:
         google.auth.exceptions.RefreshError: If the token endpoint returned
             an error.

     .. _rfc7523 section 4: https://tools.ietf.org/html/rfc7523#section-4
     """
     body = {
         'assertion': assertion,
         'grant_type': _JWT_GRANT_TYPE,
     }

     response_data = _token_endpoint_request(request, token_uri, body)

     try:
         access_token = response_data['access_token']
     except KeyError as caught_exc:
         new_exc = exceptions.RefreshError(
             'No access token in response.', response_data)
         six.raise_from(new_exc, caught_exc)

     expiry = _parse_expiry(response_data)

     return access_token, expiry, response_data


 def id_token_jwt_grant(request, token_uri, assertion):
     """Implements the JWT Profile for OAuth 2.0 Authorization Grants, but
     requests an OpenID Connect ID Token instead of an access token.

     This is a variant on the standard JWT Profile that is currently unique
     to Google. This was added for the benefit of authenticating to services
     that require ID Tokens instead of access tokens or JWT bearer tokens.

     Args:
         request (google.auth.transport.Request): A callable used to make
             HTTP requests.
         token_uri (str): The OAuth 2.0 authorization server's token endpoint
             URI.
         assertion (str): JWT token signed by a service account. The token's
             payload must include a ``target_audience`` claim.

     Returns:
         Tuple[str, Optional[datetime], Mapping[str, str]]:
             The (encoded) Open ID Connect ID Token, expiration, and additional
             data returned by the endpoint.

     Raises:
         google.auth.exceptions.RefreshError: If the token endpoint returned
             an error.
     """
     body = {
         'assertion': assertion,
         'grant_type': _JWT_GRANT_TYPE,
     }

     response_data = _token_endpoint_request(request, token_uri, body)

     try:
         id_token = response_data['id_token']
     except KeyError as caught_exc:
         new_exc = exceptions.RefreshError(
             'No ID token in response.', response_data)
         six.raise_from(new_exc, caught_exc)

     payload = jwt.decode(id_token, verify=False)
     expiry = datetime.datetime.utcfromtimestamp(payload['exp'])

     return id_token, expiry, response_data


 def refresh_grant(request, token_uri, refresh_token, client_id, client_secret,
                   scopes=None):
     """Implements the OAuth 2.0 refresh token grant.

     For more details, see `rfc678 section 6`_.

     Args:
         request (google.auth.transport.Request): A callable used to make
             HTTP requests.
         token_uri (str): The OAuth 2.0 authorizations server's token endpoint
             URI.
         refresh_token (str): The refresh token to use to get a new access
             token.
         client_id (str): The OAuth 2.0 application's client ID.
         client_secret (str): The Oauth 2.0 appliaction's client secret.
         scopes (Optional(Sequence[str])): Scopes to request. If present, all
             scopes must be authorized for the refresh token. Useful if refresh
             token has a wild card scope (e.g.
             'https://www.googleapis.com/auth/any-api').

     Returns:
         Tuple[str, Optional[str], Optional[datetime], Mapping[str, str]]: The
             access token, new refresh token, expiration, and additional data
             returned by the token endpoint.

     Raises:
         google.auth.exceptions.RefreshError: If the token endpoint returned
             an error.

     .. _rfc6748 section 6: https://tools.ietf.org/html/rfc6749#section-6
     """
     body = {
         'grant_type': _REFRESH_GRANT_TYPE,
         'client_id': client_id,
         'client_secret': client_secret,
         'refresh_token': refresh_token,
     }
     if scopes:
         body['scope'] = ' '.join(scopes)

     response_data = _token_endpoint_request(request, token_uri, body)

     try:
         access_token = response_data['access_token']
     except KeyError as caught_exc:
         new_exc = exceptions.RefreshError(
             'No access token in response.', response_data)
         six.raise_from(new_exc, caught_exc)

     refresh_token = response_data.get('refresh_token', refresh_token)
     expiry = _parse_expiry(response_data)

     return access_token, refresh_token, expiry, response_data
	# Copyright 2016 Google Inc.
	#
	# 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 client.

	This is a client for interacting with an OAuth 2.0 authorization server's
	token endpoint.

	For more information about the token endpoint, see
	`Section 3.1 of rfc6749`_

	.. _Section 3.1 of rfc6749: https://tools.ietf.org/html/rfc6749#section-3.2
	"""

	import datetime
	import json

	import six
	from six.moves import http_client
	from six.moves import urllib

	from google.auth import _helpers
	from google.auth import exceptions
	from google.auth import jwt

	_URLENCODED_CONTENT_TYPE = 'application/x-www-form-urlencoded'
	_JWT_GRANT_TYPE = 'urn:ietf:params:oauth:grant-type:jwt-bearer'
	_REFRESH_GRANT_TYPE = 'refresh_token'


	def _handle_error_response(response_body):
	""""Translates an error response into an exception.

	Args:
	response_body (str): The decoded response data.

	Raises:
	google.auth.exceptions.RefreshError
	"""
	try:
	error_data = json.loads(response_body)
	error_details = '{}: {}'.format(
	error_data['error'],
	error_data.get('error_description'))
	# If no details could be extracted, use the response data.
	except (KeyError, ValueError):
	error_details = response_body

	raise exceptions.RefreshError(
	error_details, response_body)


	def _parse_expiry(response_data):
	"""Parses the expiry field from a response into a datetime.

	Args:
	response_data (Mapping): The JSON-parsed response data.

	Returns:
	Optional[datetime]: The expiration or ``None`` if no expiration was
	specified.
	"""
	expires_in = response_data.get('expires_in', None)

	if expires_in is not None:
	return _helpers.utcnow() + datetime.timedelta(
	seconds=expires_in)
	else:
	return None


	def _token_endpoint_request(request, token_uri, body):
	"""Makes a request to the OAuth 2.0 authorization server's token endpoint.

	Args:
	request (google.auth.transport.Request): A callable used to make
	HTTP requests.
	token_uri (str): The OAuth 2.0 authorizations server's token endpoint
	URI.
	body (Mapping[str, str]): The parameters to send in the request body.

	Returns:
	Mapping[str, str]: The JSON-decoded response data.

	Raises:
	google.auth.exceptions.RefreshError: If the token endpoint returned
	an error.
	"""
	body = urllib.parse.urlencode(body)
	headers = {
	'content-type': _URLENCODED_CONTENT_TYPE,
	}

	retry = 0
	# retry to fetch token for maximum of two times if any internal failure
	# occurs.
	while True:
	response = request(
	method='POST', url=token_uri, headers=headers, body=body)
	response_body = response.data.decode('utf-8')

	if response.status == http_client.OK:
	break
	else:
	error_desc = json.loads(
	response_body).get('error_description') or ''
	if error_desc == 'internal_failure' and retry < 1:
	retry += 1
	continue
	_handle_error_response(response_body)

	response_data = json.loads(response_body)

	return response_data


	def jwt_grant(request, token_uri, assertion):
	"""Implements the JWT Profile for OAuth 2.0 Authorization Grants.

	For more details, see `rfc7523 section 4`_.

	Args:
	request (google.auth.transport.Request): A callable used to make
	HTTP requests.
	token_uri (str): The OAuth 2.0 authorizations server's token endpoint
	URI.
	assertion (str): The OAuth 2.0 assertion.

	Returns:
	Tuple[str, Optional[datetime], Mapping[str, str]]: The access token,
	expiration, and additional data returned by the token endpoint.

	Raises:
	google.auth.exceptions.RefreshError: If the token endpoint returned
	an error.

	.. _rfc7523 section 4: https://tools.ietf.org/html/rfc7523#section-4
	"""
	body = {
	'assertion': assertion,
	'grant_type': _JWT_GRANT_TYPE,
	}

	response_data = _token_endpoint_request(request, token_uri, body)

	try:
	access_token = response_data['access_token']
	except KeyError as caught_exc:
	new_exc = exceptions.RefreshError(
	'No access token in response.', response_data)
	six.raise_from(new_exc, caught_exc)

	expiry = _parse_expiry(response_data)

	return access_token, expiry, response_data


	def id_token_jwt_grant(request, token_uri, assertion):
	"""Implements the JWT Profile for OAuth 2.0 Authorization Grants, but
	requests an OpenID Connect ID Token instead of an access token.

	This is a variant on the standard JWT Profile that is currently unique
	to Google. This was added for the benefit of authenticating to services
	that require ID Tokens instead of access tokens or JWT bearer tokens.

	Args:
	request (google.auth.transport.Request): A callable used to make
	HTTP requests.
	token_uri (str): The OAuth 2.0 authorization server's token endpoint
	URI.
	assertion (str): JWT token signed by a service account. The token's
	payload must include a ``target_audience`` claim.

	Returns:
	Tuple[str, Optional[datetime], Mapping[str, str]]:
	The (encoded) Open ID Connect ID Token, expiration, and additional
	data returned by the endpoint.

	Raises:
	google.auth.exceptions.RefreshError: If the token endpoint returned
	an error.
	"""
	body = {
	'assertion': assertion,
	'grant_type': _JWT_GRANT_TYPE,
	}

	response_data = _token_endpoint_request(request, token_uri, body)

	try:
	id_token = response_data['id_token']
	except KeyError as caught_exc:
	new_exc = exceptions.RefreshError(
	'No ID token in response.', response_data)
	six.raise_from(new_exc, caught_exc)

	payload = jwt.decode(id_token, verify=False)
	expiry = datetime.datetime.utcfromtimestamp(payload['exp'])

	return id_token, expiry, response_data


	def refresh_grant(request, token_uri, refresh_token, client_id, client_secret,
	scopes=None):
	"""Implements the OAuth 2.0 refresh token grant.

	For more details, see `rfc678 section 6`_.

	Args:
	request (google.auth.transport.Request): A callable used to make
	HTTP requests.
	token_uri (str): The OAuth 2.0 authorizations server's token endpoint
	URI.
	refresh_token (str): The refresh token to use to get a new access
	token.
	client_id (str): The OAuth 2.0 application's client ID.
	client_secret (str): The Oauth 2.0 appliaction's client secret.
	scopes (Optional(Sequence[str])): Scopes to request. If present, all
	scopes must be authorized for the refresh token. Useful if refresh
	token has a wild card scope (e.g.
	'https://www.googleapis.com/auth/any-api').

	Returns:
	Tuple[str, Optional[str], Optional[datetime], Mapping[str, str]]: The
	access token, new refresh token, expiration, and additional data
	returned by the token endpoint.

	Raises:
	google.auth.exceptions.RefreshError: If the token endpoint returned
	an error.

	.. _rfc6748 section 6: https://tools.ietf.org/html/rfc6749#section-6
	"""
	body = {
	'grant_type': _REFRESH_GRANT_TYPE,
	'client_id': client_id,
	'client_secret': client_secret,
	'refresh_token': refresh_token,
	}
	if scopes:
	body['scope'] = ' '.join(scopes)

	response_data = _token_endpoint_request(request, token_uri, body)

	try:
	access_token = response_data['access_token']
	except KeyError as caught_exc:
	new_exc = exceptions.RefreshError(
	'No access token in response.', response_data)
	six.raise_from(new_exc, caught_exc)

	refresh_token = response_data.get('refresh_token', refresh_token)
	expiry = _parse_expiry(response_data)

	return access_token, refresh_token, expiry, response_data