AccessTokenRequestDto

This is the type of authentication the client is presenting for its access-token.
If the client is looking for a client-token, then this should be set to 'client_credentials'.
If the client is looking to swap an authorization grant for an access token, this should be setto 'authorization_code'
If the client is looking to swap a refresh_token for a new access token, this should be setto 'refresh_token'

If the client is swapping an authorization code for an access token, then this argument is required.If you are just obtaining a client token directly, you do not need to provide a redirect_uri. This must be the same redirect_uri that was provided to the authorizationGrant endpoint, and must also match the redirect_uri which was registered with your client when you received your client credentials.

If the client is swapping a refresh_token for an access token, then this argument is required.Otherwise, this parameter should be omitted.This parameter is the refresh_token which you obtained when you last used the access_token endpoint.

If the client is swapping an authorization code for an access token, then this argument is required.If you are just obtaining a client token directly, you do not need to provide a code. This parameteris the authorization_code which you obtained when you used the authorizationGrant endpoint.