Setting up pre-request scripts

Pre-request scripts work in much the same way that tests do in Postman. In this section, I will show you how to use them to set and get variables so that you can share data between tests. I will also show you how to build a request workflow where you can chain multiple tests together so that you can check more complex workflows. All these things are great on their own, but they do beg the question of how we can effectively run these tests, and so this section will also cover how to run your tests in the collection runner.

The first thing I want to cover, though, is how to get started with pre-request scripts. These scripts use JavaScript to send commands just like the response assertions but, as the name implies, they are run before the request is sent rather than after. Now, why would you want to do that?

I have used pre-request scripts in a couple of different ways. I have had times when I wanted to test something in an API that required sending...