I'm trying to get an unauthenticated token from Vimeo's current API v3, in order to use it to get a simple list of my own videos on my own website. I'm using a WordPress HTTP API function 'wp_remote_post' to generate a proper http request.
According to Vimeo, this is the correct way to do this and it's done with a POST request. Here are the arguments:
HTTP Method: POST
HTTP URL: api.vimeo.com/oauth/authorize/client
HTTP Headers: Authorization: basic, base64_encode( "$client_id: $client_secret" )
Request Body: grant_type=client_credentials&scope=public%20private
and getting
[body] => {"error":"You must provide a valid authenticated access token."}
[raw] => HTTP/1.1 401 Authorization Required
Why is Vimeo asking for a valid authenticated access token on an explicitly UNauthenticated call? I have provided the actual client id and client secret from my Vimeo app, using Vimeo's instructions to receive an unauthenticated access token. I'm sending the request from my local environment.
I have checked the similar question How to generate Vimeo unauthenticated access token? and have followed everything outlined there. No dice, and i've been trying to do this for hours.