Postman is a valuable tool to work with APIs, especially when testing and making ad hoc requests outside of an automated production solution. In terms of where a Power BI developer may find Postman useful, it sits somewhere between the documentation’s “Try It” functionality and a more production-worthy solution incorporating tools like Azure DevOps, Logic Apps/Power Automate, a Power BI custom connector, etc.
The ideas in this post extend an original post from Carl de Souza. Carl shows how to obtain an OAuth2 access token but does so with hardcoded values. Additional API requests use the token from the original response, but he also manually provides this token to those subsequent API calls.
David has a clever technique for getting the bearer token, so check it out.