How to write functional tests in a system with microservices?

Question

Functional testing

What is the best way to write functional tests if there are calls to microservices in the system? How can services be blocked? Are there other solutions for system testing?

Answer 1

How can services be blocked?

You won't believe it. Mokami! Services usually communicate over HTTP/gRPC. Here are the mock answers, intercepting the actual sending of the request.
But the best way to write integration tests is to normally raise an isolated instance of the entire infrastructure with fixtures and without mocks. True, it can be very expensive and time consuming.