authlib/oauth2/rfc6749/grants/client_credentials.py
import logging
from .base import BaseGrant, TokenEndpointMixin
from ..errors import UnauthorizedClientError
log = logging.getLogger(__name__)
class ClientCredentialsGrant(BaseGrant, TokenEndpointMixin):
"""The client can request an access token using only its client
credentials (or other supported means of authentication) when the
client is requesting access to the protected resources under its
control, or those of another resource owner that have been previously
arranged with the authorization server.
The client credentials grant type MUST only be used by confidential
clients::
+---------+ +---------------+
| | | |
| |>--(A)- Client Authentication --->| Authorization |
| Client | | Server |
| |<--(B)---- Access Token ---------<| |
| | | |
+---------+ +---------------+
https://tools.ietf.org/html/rfc6749#section-4.4
"""
GRANT_TYPE = 'client_credentials'
def validate_token_request(self):
"""The client makes a request to the token endpoint by adding the
following parameters using the "application/x-www-form-urlencoded"
format per Appendix B with a character encoding of UTF-8 in the HTTP
request entity-body:
grant_type
REQUIRED. Value MUST be set to "client_credentials".
scope
OPTIONAL. The scope of the access request as described by
Section 3.3.
The client MUST authenticate with the authorization server as
described in Section 3.2.1.
For example, the client makes the following HTTP request using
transport-layer security (with extra line breaks for display purposes
only):
.. code-block:: http
POST /token HTTP/1.1
Host: server.example.com
Authorization: Basic czZCaGRSa3F0MzpnWDFmQmF0M2JW
Content-Type: application/x-www-form-urlencoded
grant_type=client_credentials
The authorization server MUST authenticate the client.
"""
# ignore validate for grant_type, since it is validated by
# check_token_endpoint
client = self.authenticate_token_endpoint_client()
log.debug('Validate token request of %r', client)
if not client.check_grant_type(self.GRANT_TYPE):
raise UnauthorizedClientError()
self.request.client = client
self.validate_requested_scope()
def create_token_response(self):
"""If the access token request is valid and authorized, the
authorization server issues an access token as described in
Section 5.1. A refresh token SHOULD NOT be included. If the request
failed client authentication or is invalid, the authorization server
returns an error response as described in Section 5.2.
An example successful response:
.. code-block:: http
HTTP/1.1 200 OK
Content-Type: application/json
Cache-Control: no-store
Pragma: no-cache
{
"access_token":"2YotnFZFEjr1zCsicMWpAA",
"token_type":"example",
"expires_in":3600,
"example_parameter":"example_value"
}
:returns: (status_code, body, headers)
"""
token = self.generate_token(scope=self.request.scope, include_refresh_token=False)
log.debug('Issue token %r to %r', token, self.client)
self.save_token(token)
self.execute_hook('process_token', self, token=token)
return 200, token, self.TOKEN_RESPONSE_HEADER