Cognos Analytics

We're struggling to get connected to a Salesforce API for JSON data. They do use Oauth2.0 but it doesn't seem to fit with the examples for the AutoRest driver. The only authentication that seems to work for us in Postman is password grant but to the token URI not an authorization URI. We have to pass the grant_type parameter too. When I try the example for password grant I get invalid grant type even if I try adding grant_type to the JDBC string, which is not mentioned as an option. Thus I don't think it's being passed. Does anyone have experience with connecting to Salesforce for JSON data and does this sound like it would have to be custom authentication instead?

P.S. I have a ticket with support but so far I've only been given references to the documentation.

We were successful in getting this working. It is indeed the Oath2 password grant flow. IBM support suggested enabling debug logging using the jdbc parameter ;DebugRecord=C:\Some\Folder which helped me to identify that the apostrophes around the user and password, which appear in the Progress DataDirect documentation, were being passed thus making the credentials invalid. Once I removed those it started working. The debug log also showed that the driver was properly translatting the supplied parameters and sending the grant_type=password automatically.