Retrieve access token for Yahoo API using OAuth 2.0 and Python requests

Question

I am trying to retrieve the access token for the Yahoo API, using the explicit grant flow as described in this document: https://developer.yahoo.com/oauth2/guide/flows_authcode

Everything is fine until Step 4: Exchange authorization code for Access Token

I wrote the following python script to retrieve the code:

import urllib2
import requests
import json



url = 'https://api.login.yahoo.com/oauth2/get_token'
body = "grant_type=authorization_code&redirect_uri=oob&code=************"
headers = {
'Authorization': 'Basic **************', 
'Content-Type': 'application/json'
}

r = requests.post(url, data=body, headers=headers)
print r

Note: I replaced sensitive data with "****"

Now, when I execute the script, I only get the "401" error message.

I am 100% sure that the login credentials are fine, so it seems to be related to the way I make the request. It's also the first time that I am using "requests" in python.

Would be great, if you could give me some feedback on the code, and if I am passing the header and body information correctly. I am especially unsure about the passing of the body. The documentation only states the following:

Sample Request Body: grant_type=authorization_code&redirect_uri=https%3A%2F%2Fwww.example.com&code=abcdef

Answer 1

Change your body variable to a dict, i.e.,

body = {
    'grant_type': 'authorization_code',
    'redirect_uri': 'oob',
    'code': '************',
}

No other changes are needed. Hope it helps.

Answer 2

Tough the problem already solved. But may be other user can still get the same 401 error even if they use correct dict as me. The problem is that the code generated in step 2 in the link can be only use ONCE. And this will get the same 401 error. This took me some time to figure it out. Hope this helps others.