Demonstrate how to use docker-maven-plugin to fire up a MongoDB container to be used during integration tests.
Note: With Spring Boot 1.5 you could use @DataMongoTest with the embedded MongoDB, but this is not the point here.
First: Configure docker-maven-plugin with the containers you need, here: mongodb:
<plugin> <groupId>io.fabric8</groupId> <artifactId>docker-maven-plugin</artifactId> <version>0.20.1</version> <configuration> <!-- Those are the containers you want to run no need to configure ports yet --> <images> <image> <name>mongo:3.2.9</name> <alias>mongo-db</alias> <run> <!-- Tells the plugin to wait for a log entry for 60s max. --> <wait> <log>waiting for connections on port 27017</log> <time>60000</time> </wait> </run> </image> </images> </configuration> <!-- Configure the execution of the plugin itself --> <executions> <execution> <id>prepare-it-database</id> <!-- During this phase… --> <phase>pre-integration-test</phase> <!-- …run the start goal --> <goals> <goal>start</goal> </goals> <configuration> <images> <image> <alias>mongo-db</alias> <run> <!-- Here we need to configure the ports, the Mongo image offers 27018, we tell the plugin to map it onto a random local free port --> <ports> <!-- Maps the random port onto a Maven property --> <port>mongo-db-it.port:27017</port> </ports> </run> </image> </images> </configuration> </execution> <execution> <id>remove-it-database</id> <!-- Stop the containers after integration test --> <phase>post-integration-test</phase> <goals> <goal>stop</goal> </goals> </execution> </executions> </plugin>No tests are executed yet. I prefer the maven-failsafe-plugin for executing integration tests. maven-failsafe-plugin makes sure that a pre and post phase are executed. It also offers the possiblity to push any maven property into the vm environment which we do now with the generated property mongo-db-it.port from the docker-maven-plugin
<plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-failsafe-plugin</artifactId> <configuration> <environmentVariables> <!-- Push the Maven property into the environment under the given name (here: spring.data.mongodb.port) --> <spring.data.mongodb.port>${mongo-db-it.port}</spring.data.mongodb.port> </environmentVariables> </configuration> </plugin>You can push the whole connectstring into your enviroment.
As we are using Spring Boot here, the integration test SomeDocumentRepositoryIT is pretty simple:
@ExtendWith(SpringExtension.class) @DataMongoTest public class SomeDocumentRepositoryIT { private static final Logger LOG = LoggerFactory .getLogger(SomeDocumentRepositoryIT.class); @Autowired private SomeDocumentRepository someDocumentRepository; @Autowired private MongoTemplate mongoTemplate; @Test public void doSomething() { someDocumentRepository.deleteAll(); final SomeDocument d = someDocumentRepository.save(new SomeDocument("foobar")); LOG.info("Stored document with id {}", d.getId()); final SomeDocument d2 = mongoTemplate.findById(d.getId(), SomeDocument.class); assertThat(d2.getValue(), is("foobar")); } }The property spring.data.mongodb.port is automatically picked up from the enviroment with higher priority than configuration files so the test runs agains our container.