How to conditionally set the response for an intercepted server-side request per test?

[Addison-Dalton]

Hello!

I have a remix app that I'm using playwright to write e2e tests for. I have a server-side request that gets a config object. I was able to setup MSW to intercept this, and return my defined handler's response. Unfortunately, this alone is not very useful for me. The /config endpoint returns an object with many different settings, and I need a way to define the response per test and have the MSW intercept return that.

I've seen a few examples of how to do this, but none of them seem to be for server-side requests, only client-side. So I'm curious if that's even possible, and, if so, how? Thanks!

[kettanaito]

Hi, @Addison-Dalton. That's a great question. What you are describing is currently not supported in any test runner or framework. The idea of affecting the network of a different process is rather new.

We have a work-in-progress API to allow you to do precisely what you described called setupRemoteServer(). See #1617. It establishes a WebSocket bridge between any two given processes, allowing one process to affect the network of the other.

I've designed that API exactly for your use case: to allow per-test server-side network changes during e2e testing.

That feature still needs development and you are unlikely to use it in its current state. If this is something you depend on at work, please consider becoming a sponsor. I would be happy to prioritize that feature or even finish it, given enough budget. Otherwise, I will get to it when I have the time.

[Addison-Dalton]

Thanks for the reply! I certainly understand the limitation. Ultimately what I did was skip the server-side rendering step, and just do client-side rendering. The request can now be picked up by playwright, and intercepted through its API.