Component tests

If you have provided the unit tests for all the key classes and interfaces in the application, you may proceed to the component tests. The main idea of component tests is to instantiate the full microservice in memory using in-memory test doubles and data stores. This allows us to skip the network connections. While for unit tests we were mocking all the database or HTTP clients, here we do not mock anything. We provide an in-memory data source for the database client and we simulate HTTP responses for the REST client.

Running tests with an in-memory database

One of the reasons I chose MongoDB is that it can be easily embedded with a Spring Boot application for testing purposes. To enable an embedded MongoDB for your project, include the following dependency in Maven pom.xml:

<dependency>
    <groupId>de.flapdoodle.embed</groupId>
    <artifactId>de.flapdoodle.embed.mongo</artifactId>
    <scope>test</scope>
</dependency>

Spring...