I am currently working on a PayPal integration using the REST API methods PayPal provides.

To be able to use the API Methods I first need to generate an OAuth token with a REST API Post.

I can do it without any problem on Postman, however I am unable to do this on OutSystems.

The REST API call I make: 

A Post with the following structure:

  • header: content-type: application/x-www-form-urlencoded;
  • body: grant_type:client_credentials;
  • Basic authentication filled in (user and password).

I get the following error:

HTTP/1.1 400 BadRequestContent-Type: application/json{  "error": "unsupported_grant_type",  "error_description": "Grant Type is NULL"}

Has anyone had this problem before?

PayPal example using Postman: https://developer.paypal.com/docs/api/overview/#make-your-first-call

Hi Reinaldo,

Did you check what the Platform sends to PayPal? If not, increase the logging level of the REST API, and check the logging. This might give you a starting point for debugging.