In the previous chapter, we discussed how to carry out functional testing of a microservice to ensure the quality of the intended requirement. We have written unit tests to ensure that individual units function as expected and integration tests to check external dependencies, such as databases or external service calls. However, in a microservice-based architecture, performance testing is needed to test all individual components, such as the microservices themselves, the REST API, or the database. Performance testing ensures the performance of the overall application, allowing it to send fast responses to clients.
When designing a performance test for a microservice-based application, it has to test the performance of the APIs as well as the performance of external dependencies. Load testing tools such as JMeter, the Ready API, or Gatling can...