In Postman, I am able to successfully request a new token using the GUI. I'm wondering how to do this programatically. Or at least see the HTTP request that Postman is making. I've tried viewing it by monitoring the network traffic in Chrome, and with Wireshark, but without success. Thank you
well, OAuth2 is quite a big subject and you are not really providing a lot of details.
Postman is just a client, it creates requests based on the data you gave it so you don't need to monitor anything, you should know how you set it up and then simply mirror that in whatever language you want. Look at headers and post data specifically.
All I can do is point you to an extensive article I wrote on OAuth2, it shows a complete implementation, how to use Postman to create the correct requests and then how to write code which makes it all work.
If you don't use dot net, you can still understand all the concepts and it should be trivial to do the same thing using a different language.
https://eidand.com/2015/03/28/authorization-system-with-owin-web-api-json-web-tokens/
