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ancso's avatar
ancso
Helpful | Level 6
4 years ago
Solved

Can't get PKCE access token uses javascript fetch request

I am trying to utilize the PKCE in a background script of chrome extension example shows the following:   curl https://api.dropbox.com/oauth2/token \ -d code=<AUTHORIZATION_CODE> \ -d grant_typ...
  • ancso's avatar
    ancso
    4 years ago

    yes!
    that was the problem
    my apologies I missed these arguments in the request URL

     

    however,
    i am now getting the error 

     

    {error: 'invalid_grant', error_description: 'invalid code verifier'}

     

     

    The URL includes both code_challenge and code_challenge_method
    and looks like:

     

    https://www.dropbox.com/oauth2/authorize?response_type=code&client_id=<client_id>&code_challenge=<code_challenge>&code_challenge_method=S256

     


    and the parameters sent to oauth2/token are:

     

    client_id=<client_id>&grant_type=authorization_code&code=<auth code from dropbox>&code_verifier=<128 char verifier>

     

     

    i also made sure that <code challenge> is a SHA256 hash of <128 char verifier> by testing it at https://emn178.github.io/online-tools/sha256.html

    what am i missing?

ancso's avatar
ancso
Helpful | Level 6
4 years ago

yes,
i experience the same behavior
if using an expired code i get the same error "code doesn't exist or has expired":

HTTP/1.1 400 Bad Request
Content-Security-Policy: sandbox allow-forms allow-scripts
Content-Type: application/json
Accept-Encoding: identity,gzip
Date: Wed, 12 Jan 2022 02:27:14 GMT
Server: envoy
Content-Length: 84
X-Dropbox-Response-Origin: far_remote
X-Dropbox-Request-Id: 7ff4794a94a846b0bfcbc750fbe48fd5

{"error": "invalid_grant", "error_description": "code doesn't exist or has expired"}


however
if using a working code i get:

HTTP/1.1 400 Bad Request
Content-Security-Policy: sandbox allow-forms allow-scripts
Content-Type: application/json
Accept-Encoding: identity,gzip
Date: Wed, 12 Jan 2022 02:25:18 GMT
Server: envoy
Content-Length: 97
X-Dropbox-Response-Origin: far_remote
X-Dropbox-Request-Id: 320762d3550c4d8a8e9e46a5ddc6b091

{"error": "invalid_request", "error_description": "No auth function available for given request"}

 

ancso's avatar
ancso
Helpful | Level 6
4 years ago

is there a way we can debug this online together?
maybe in an online meeting?

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