service_account.py 文件源码

def from_json_keyfile_name(cls, filename, scopes='',
                               token_uri=None, revoke_uri=None):

        """Factory constructor from JSON keyfile by name.

        Args:
            filename: string, The location of the keyfile.
            scopes: List or string, (Optional) Scopes to use when acquiring an
                    access token.
            token_uri: string, URI for OAuth 2.0 provider token endpoint.
                       If unset and not present in the key file, defaults
                       to Google's endpoints.
            revoke_uri: string, URI for OAuth 2.0 provider revoke endpoint.
                       If unset and not present in the key file, defaults
                       to Google's endpoints.

        Returns:
            ServiceAccountCredentials, a credentials object created from
            the keyfile.

        Raises:
            ValueError, if the credential type is not :data:`SERVICE_ACCOUNT`.
            KeyError, if one of the expected keys is not present in
                the keyfile.
        """
        with open(filename, 'r') as file_obj:
            client_credentials = json.load(file_obj)
        return cls._from_parsed_json_keyfile(client_credentials, scopes,
                                             token_uri=token_uri,
                                             revoke_uri=revoke_uri)