Checking an out request with a correlation id

I am looking for a performance tester tool with I can check that for a certain request an another request from the app has been made with a same correlation id (aka user id).
Sample code would look like this:
post to myapp.com/user/{__VU}
check that externalservice.com/user/{__VU} have been called.
The external service url is configurable from outside the app.
In order to achieve this a mocked external service and a cross checker is needed, do you have this functionality?

Hi @lbodi, sorry for the late reply,

As far as I understand you want for k6 to be able to serve http and then you to make another service call k6 in order to check that it actually does it ?
There is no such functionality, and I am somewhat skeptic of adding it as this doesn’t seem like a load testing functionality but just as general testing one … You should probably write an issue and we can discuss whether it is something that we want to have in k6 in the future.

Arguably you can have another service that does this job. I have used mmock in the past and it has a way to verify that a given call was made. There are other tools which “mock” http responses and probably some of them have a way to verify that an api was called.