Question

Suddenly, I am getting an error during the Oauth process, after my app has been given permission for access by the user and a authorization code is delivered to my redirect url. I’ve been using the same code for a couple weeks now, and it has been working fine. I’m pretty certain I haven’t made any changes.

Is there an issue with Google Drive API today?

The error occurs here in Python code here:

credentials = flow.step2_exchange(authorization_code)

Error message:

FlowExchangeError: Invalid response 400.

The entire exchange_code method as copied from Google example:

def exchange_code(authorization_code):
  """Exchange an authorization code for OAuth 2.0 credentials.

  Args:
    authorization_code: Authorization code to exchange for OAuth 2.0
                    credentials.
  Returns:
    oauth2client.client.OAuth2Credentials instance.
  Raises:
    CodeExchangeException: an error occurred.


  """

  logging.debug(authorization_code);

  flow = flow_from_clientsecrets(CLIENTSECRETS_LOCATION, ' '.join(SCOPES))

  flow.redirect_uri = REDIRECT_URI


  try:
    credentials = flow.step2_exchange(authorization_code)
    return credentials
  except FlowExchangeError, error:
    logging.error('An error occurred: %s', error)
    raise CodeExchangeException(None)

Using Oauth Playground, I get the following error response:

HTTP/1.1 400 Ok
Status: 400
Content-length: 37
X-xss-protection: 1; mode=block
X-content-type-options: nosniff
X-google-cache-control: remote-fetch
-content-encoding: gzip
Server: GSE
Via: HTTP/1.1 GWA
Pragma: no-cache
Cache-control: no-cache, no-store, max-age=0, must-revalidate
Date: Fri, 10 Aug 2012 03:23:54 GMT
X-frame-options: SAMEORIGIN
Content-type: application/json
 Expires: Fri, 01 Jan 1990 00:00:00 GMT
{
  "error" : "unauthorized_client"
}

Any ideas why this would start happening when the code was working for weeks as it is now?

Thanks,
Chris

Answer 1

I was finally able to get the code working again. I reverted the GAE app version to my prior version. Oauth exchange_code worked again. Then I took it back to the current version on GAE, with no changes to the code whatsoever, and it continues to work.

So the oauth process did stop working when I recently created new version in GAE with no changes to the code. For what it’s worth…..