OAuth2 Tokens in Postman

I like to use Postman when developing REST APIs. It allows me to save, group and share different requests, prepare different payloads to test different scenarios and it helps with manual (some people use it even for automatic) testing. Furthermore, securing APIs with OAuth2 is very common - it’s secure and practical. But when it comes to combining the two, it can be a bit tricky to get things running smoothly.

I don’t like to change my development environment for the sake of convenience, so I do not disable OAuth locally. This means that I have to pass a valid OAuth token with each request. This can get very annoying though, you have to request a token and then paste it into each request etc., so I started looking into automatic OAuth token request functionality in Postman. I had issues to get it working locally (and could not get it working), but it does not even completely solve the annoying part of making sure you have the correct token in a request.

I grew tired of copy-pasting tokens and automated the whole thing. Once I spent few minutes and looked into it I was banging my head against the wall asking myself why I hadn’t done this earlier.

Here is my setup:
I set up a simple test script in Postman which is automatically run after each Request Token request, which sets the retrieved token into a postman environment variable.

var jsonData = JSON.parse(responseBody);
postman.setEnvironmentVariable("accessToken", jsonData.access_token);

Next, I just use this variable in every saved request header like this:

Authorization: Bearer {{accessToken}}

And that’s it - no need for anything else, just request a token once and use it until it expires with all the requests you have!