Client(None, session) raises AttributeError: 'NoneType' object has no attribute '__module__' (using with Authlib)

[ftnext]

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---

Describe the bug
It seems that we can't pass None to gspread.Client, even though the documentation says you can.

gc = Client(None, session)

To Reproduce

1. pip install gspread authlib (See Environment info)
2. create main.py (See Code examples)
3. python main.py

Expected behavior
returns Client (not raise Exception)
expected in https://blog.authlib.org/2018/authlib-for-gspread or https://gspread.readthedocs.io/en/latest/advanced.html#using-authlib

Code example*
ref: https://blog.authlib.org/2018/authlib-for-gspread

import json

from authlib.integrations.requests_client import AssertionSession
from gspread import Client


def create_assertion_session(conf_file, scopes, subject=None):
    with open(conf_file, 'r') as f:
        conf = json.load(f)

    token_url = conf['token_uri']
    issuer = conf['client_email']
    key = conf['private_key']
    key_id = conf.get('private_key_id')

    header = {'alg': 'RS256'}
    if key_id:
        header['kid'] = key_id

    # Google puts scope in payload
    claims = {'scope': ' '.join(scopes)}
    return AssertionSession(
        grant_type=AssertionSession.JWT_BEARER_GRANT_TYPE,
        token_endpoint=token_url,
        issuer=issuer,
        audience=token_url,
        claims=claims,
        subject=subject,
        key=key,
        header=header,
    )


credential_file = "my-credential.json"
scopes = [
    'https://www.googleapis.com/auth/spreadsheets',
    'https://www.googleapis.com/auth/drive',
]
session = create_assertion_session(credential_file, scopes)

gc = Client(None, session)

Environment info:

• Operating System: macOS (10.14.6)
• Python version: 3.8.1
• gspread version: 3.6.0

Authlib 0.14.2

Stack trace

Traceback (most recent call last):
  File "main.py", line 41, in <module>
    gc = Client(None, session)
  File "/Users/.../test_env/lib/python3.8/site-packages/gspread/client.py", line 39, in __init__
    self.auth = convert_credentials(auth)
  File "/Users/.../test_env/lib/python3.8/site-packages/gspread/utils.py", line 50, in convert_credentials
    module = credentials.__module__
AttributeError: 'NoneType' object has no attribute '__module__'

Additional context
temporally workaround: Use gspread.service_account (Not use Authlib)
gc = service_account(credential_file, scopes)
ref: #768

[lepture]

It was caused by #711

[burnash]

Thank you for reporting this. I'm going to release it on PyPI with the version 3.7.0

[mustafa89]

@burnash The code on 3.6.0 is quite old now. Would love to get a new release so I can directly pip install rather than using the git commit for this feature.

Thanks :)