spring boot - embedded mongodb connection refused

Question

In this example spring boot project I want to test the MongoRepository persistent layer as well as the Service class that uses the repository using an embedded mongodb. However, I get a Connection refused: connect error ( java.net.ConnectException ), see below for a more detailed stacktrace.

This is my test class

@RunWith(SpringRunner.class)
@SpringBootTest(classes=MongoConfig.class)
@TestPropertySource(locations = "classpath:application-test.properties")
public class Test_TimezoneDao {

    private static final Logger LOG = LoggerFactory.getLogger(Test_TimezoneDao.class);

    @Autowired private TimezoneDao dao;
    @Autowired private CounterService counterService;


    @Test
    public void test() 
    { /*...*/ }
}

using this config class

@Profile("test")
@SpringBootConfiguration
@ComponentScan(basePackages= {"com.example.demomongodb"})
@EnableMongoRepositories(basePackages= {"com.example.demomongodb"})
@EnableAutoConfiguration
@AutoConfigureDataMongo
public class MongoConfig 
{ }

For spring to use the embedded mongodb I imported

       <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-data-mongodb</artifactId>
       </dependency>

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

        <dependency>
            <groupId>cz.jirutka.spring</groupId>
            <artifactId>embedmongo-spring</artifactId>
            <version>1.3.1</version>
            <scope>test</scope>
        </dependency>

and configured in application-test.properties

spring.profiles.active=test
# tried both random port (port=0) and deterministic port
spring.data.mongodb.port=27019
spring.data.mongodb.host=localhost
spring.data.mongodb.database=mongo-example

The full error is this:

com.mongodb.MongoSocketOpenException: Exception opening socket
    at com.mongodb.connection.SocketStream.open(SocketStream.java:62) ~[mongodb-driver-core-3.6.3.jar:na]
    at com.mongodb.connection.InternalStreamConnection.open(InternalStreamConnection.java:126) ~[mongodb-driver-core-3.6.3.jar:na]
    at com.mongodb.connection.DefaultServerMonitor$ServerMonitorRunnable.run(DefaultServerMonitor.java:114) ~[mongodb-driver-core-3.6.3.jar:na]
    at java.lang.Thread.run(Thread.java:745) [na:1.8.0_92]
Caused by: java.net.ConnectException: Connection refused: connect
    at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method) ~[na:1.8.0_92]
    at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:85) ~[na:1.8.0_92]
    at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) ~[na:1.8.0_92]
    at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) ~[na:1.8.0_92]
    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) ~[na:1.8.0_92]
    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172) ~[na:1.8.0_92]
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[na:1.8.0_92]
    at java.net.Socket.connect(Socket.java:589) ~[na:1.8.0_92]
    at com.mongodb.connection.SocketStreamHelper.initialize(SocketStreamHelper.java:59) ~[mongodb-driver-core-3.6.3.jar:na]
    at com.mongodb.connection.SocketStream.open(SocketStream.java:57) ~[mongodb-driver-core-3.6.3.jar:na]
    ... 3 common frames omitted

Thanks for the help!

EDIT

Also tried with deleting mongo host and port from all application properties, same issue

EDIT 2

When I change the mongodb port to 0 as recommended in the spring boot docs I get java.net.ConnectException: connect: Address is invalid on local machine, or port is not valid on remote machine . So it really tries port 0 and doesnt use a random port as described on the spring boot docs. This seems to not work at all..

Answer 1

I think you need to create this bean as well in mongo config.

@Bean(destroyMethod="close")
public Mongo mongo() throws IOException {
    return new EmbeddedMongoBuilder()
        .version("2.4.5")
        .bindIp("127.0.0.1")
        .port(12345)
        .build();
}

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