I need to send the variables client id, secret, username and password. This request will generate a access token.
My configuration from oauth2 Credentials:
Is it not just a case of adding a HTTP Request node to your work flow then setting the OAuth 2 API option for credentials and setting the request method to post? I have not played with Akeneo but this is probably the first thing I would try just to see what happens.
Not because I have akeneo installed in a virtual machine and I access it from the internal network.
All I need is to mount Akeneo inside a server and not locally.