requests.exceptions.HTTPError with GoogleOAuth2

[egorov-aleksey]

I have Flask app. When I try authenticate with Google I've got error:

requests.exceptions.HTTPError: 401 Client Error: Unauthorized for url: https://accounts.google.com/o/oauth2/token
Traceback:

127.0.0.1 - - [04/Apr/2017 16:06:51] "GET /login/google-oauth2/?next=%2F HTTP/1.1" 302 -
127.0.0.1 - - [04/Apr/2017 16:07:04] "GET /complete/google-oauth2/?state=iUcmi1fyzXKoyhiQGMEVskFfSp1G9O3F&code=4/ZIS2te9WsomtVHYHak884Tz88eeZRahYMDj35NR6KTo&authuser=0&session_state=f9247b499ccf7eb774bb453c1a0348b4de917afb..6299&prompt=consent HTTP/1.1" 500 -
Traceback (most recent call last):
  File "/project/env/lib/python3.4/site-packages/flask/app.py", line 1997, in __call__
    return self.wsgi_app(environ, start_response)
  File "/project/env/lib/python3.4/site-packages/flask/app.py", line 1985, in wsgi_app
    response = self.handle_exception(e)
  File "/project/env/lib/python3.4/site-packages/flask/app.py", line 1540, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "/project/env/lib/python3.4/site-packages/flask/_compat.py", line 33, in reraise
    raise value
  File "/project/env/lib/python3.4/site-packages/flask/app.py", line 1982, in wsgi_app
    response = self.full_dispatch_request()
  File "/project/env/lib/python3.4/site-packages/flask/app.py", line 1614, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/project/env/lib/python3.4/site-packages/flask/app.py", line 1517, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/project/env/lib/python3.4/site-packages/flask/_compat.py", line 33, in reraise
    raise value
  File "/project/env/lib/python3.4/site-packages/flask/app.py", line 1612, in full_dispatch_request
    rv = self.dispatch_request()
  File "/project/env/lib/python3.4/site-packages/flask/app.py", line 1598, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/project/env/lib/python3.4/site-packages/social_flask/utils.py", line 43, in wrapper
    return func(backend, *args, **kwargs)
  File "/project/env/lib/python3.4/site-packages/social_flask/routes.py", line 23, in complete
    *args, **kwargs)
  File "/project/env/lib/python3.4/site-packages/social_core/actions.py", line 41, in do_complete
    user = backend.complete(user=user, *args, **kwargs)
  File "/project/env/lib/python3.4/site-packages/social_core/backends/base.py", line 39, in complete
    return self.auth_complete(*args, **kwargs)
  File "/project/env/lib/python3.4/site-packages/social_core/utils.py", line 253, in wrapper
    return func(*args, **kwargs)
  File "/project/env/lib/python3.4/site-packages/social_core/backends/oauth.py", line 394, in auth_complete
    method=self.ACCESS_TOKEN_METHOD
  File "/project/env/lib/python3.4/site-packages/social_core/backends/oauth.py", line 372, in request_access_token
    return self.get_json(*args, **kwargs)
  File "/project/env/lib/python3.4/site-packages/social_core/backends/base.py", line 227, in get_json
    return self.request(url, *args, **kwargs).json()
  File "/project/env/lib/python3.4/site-packages/social_core/backends/base.py", line 223, in request
    response.raise_for_status()
  File "/project/env/lib/python3.4/site-packages/requests/models.py", line 909, in raise_for_status
    raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 401 Client Error: Unauthorized for url: https://accounts.google.com/o/oauth2/token

pip freeze:

alembic==0.9.1
click==6.7
defusedxml==0.5.0
Flask==0.12.1
Flask-Cors==3.0.2
Flask-Fixtures==0.3.7
Flask-Login==0.4.0
Flask-Migrate==2.0.3
Flask-Script==2.0.5
Flask-SQLAlchemy==2.2
future==0.16.0
itsdangerous==0.24
Jinja2==2.9.6
Mako==1.0.6
MarkupSafe==1.0
oauthlib==2.0.2
psycopg2==2.7.1
pycryptodomex==3.4.5
pyjwkest==1.3.2
PyJWT==1.4.2
python-editor==1.0.3
python-social-auth==0.3.6
python3-openid==3.1.0
requests==2.13.0
requests-oauthlib==0.8.0
six==1.10.0
social-auth-app-flask==1.0.0
social-auth-app-flask-sqlalchemy==1.0.1
social-auth-core==1.2.0
social-auth-storage-sqlalchemy==1.0.1
SQLAlchemy==1.1.8
Werkzeug==0.12.1

What I'm doing wrong?

[goozmake]

I have same error!

[nh-99]

What worked for me was to enable the Google+ API on the Google Developer Console.

[randyyuan]

I had the same error with both Google+ API and Gmail API enabled on Google Developer Console

Update: I think my problem was due to expired tokens on the app's side.