Introduction to MSW

MSW is a tool that allows us to create mocked APIs. It works as a service worker that intercepts any API request that has its mocked version defined. We can inspect the requests and responses in the Network tab of our browser the same way as if we were calling the real API.

To get a high-level overview of how it works, let’s take a look at the diagram provided on their website:

Figure 5.1 – MSW workflow diagram

One great thing about MSW is that our application will behave the same as if it were using a real API, and it’s pretty trivial to switch to using the real API by turning mocked endpoints off and not intercepting requests.

Another great thing is that since the interception happens at the network level, we will still be able to inspect our requests in the Network tab of the browser dev tools.

Configuration overview

We already have the MSW package installed as a dev dependency. The msw mocked API can...