Cloud Native Java

Chapter 4. Testing

A cloud native application is optimized for fast feedback at every tier, from components all the way to entire systems. Testing is the primary way to drive that feedback loop. Microservices come in systems. Spring Boot provides robust integration testing support: support to help capture the integration between components in a system.

As applications become increasingly distributed, the strategies for how we effectively write tests change considerably. The practice of integration testing focuses on writing and executing tests against a group of software modules that depend on one another. Integration testing is a standard practice in software development where developers who are working on separate modules or components are able to automate a set of test cases which exist to ensure that the expected functionality of integration remains true—especially when changes are made to code that affects an integration. It can often be the case that integration testing requires executing tests in a shared integration environment. In this scenario, applications may be subject to concurrently sharing external resources, such as a database or an application server.

Cloud native applications are designed to take advantage of the ephemeral nature of a cloud environment; we should focus on designing integration tests so that they can be executed in an ephemeral environment that is decoupled from other applications. In many cases, cloud native applications depend on backing services. ...