[Feature]: Add an annotation similar to `@org.testcontainers.junit.jupiter.Container` to the `org.testcontainers.containers.Network` class

[linghengqian]

Module

Core

Problem

• For the org.testcontainers.containers.Network mentioned in https://java.testcontainers.org/features/networking/ , it always needs to be closed manually by calling Network#close().
• Currently, using org.testcontainers.containers.Network in junit5 always requires adding an additional @AfterAll. Like the following,

import org.junit.jupiter.api.AfterAll;
import org.junit.jupiter.api.Test;
import org.testcontainers.containers.GenericContainer;
import org.testcontainers.containers.Network;
import org.testcontainers.junit.jupiter.Container;
import org.testcontainers.junit.jupiter.Testcontainers;
@Testcontainers
public class SimpleTest {
    private static final Network NETWORK = Network.newNetwork();
    @Container
    private static final GenericContainer<?> ZOOKEEPER_CONTAINER = new GenericContainer<>("zookeeper:3.9.3-jre-17")
            .withNetwork(NETWORK)
            .withNetworkAliases("foo")
            .withExposedPorts(2181);
    @Container
    public static final GenericContainer<?> OPEN_GAUSS_CONTAINER = new GenericContainer<>("opengauss/opengauss:5.0.0")
            .withNetwork(NETWORK)
            .withEnv("GS_PASSWORD", "openGauss@123")
            .withExposedPorts(5432);
    @AfterAll
    static void afterAll() {
        NETWORK.close();
    }
    @Test
    void test() {
        ZOOKEEPER_CONTAINER.getMappedPort(2181);
        OPEN_GAUSS_CONTAINER.getMappedPort(5432);
    }
}

Solution

• I would like to avoid using org.junit.jupiter.api.AfterAll as follows.

import org.junit.jupiter.api.Test;
import org.testcontainers.containers.GenericContainer;
import org.testcontainers.containers.Network;
import org.testcontainers.junit.jupiter.Container;
import org.testcontainers.junit.jupiter.Testcontainers;
@Testcontainers
public class SimpleTest {
    @org.testcontainers.junit.jupiter.Network
    private static final Network NETWORK = Network.newNetwork();
    @Container
    private static final GenericContainer<?> ZOOKEEPER_CONTAINER = new GenericContainer<>("zookeeper:3.9.3-jre-17")
            .withNetwork(NETWORK)
            .withNetworkAliases("foo")
            .withExposedPorts(2181);
    @Container
    public static final GenericContainer<?> OPEN_GAUSS_CONTAINER = new GenericContainer<>("opengauss/opengauss:5.0.0")
            .withNetwork(NETWORK)
            .withEnv("GS_PASSWORD", "openGauss@123")
            .withExposedPorts(5432);
    @Test
    void test() {
        ZOOKEEPER_CONTAINER.getMappedPort(2181);
        OPEN_GAUSS_CONTAINER.getMappedPort(5432);
    }
}

• It would be nice if an annotation like @org.testcontainers.junit.jupiter.Container could be added to the org.testcontainers.containers.Network class. Maybe the class name is @org.testcontainers.junit.jupiter.Network.

Benefit

• Simplifies use.

Alternatives

• Just to align the usage of Junit4 on Junit5. This is a derivative of Support connecting to HiveServer2 with ZooKeeper Service Discovery enabled in GraalVM Native Image apache/shardingsphere#33768 and Improve GraalVM Reachability Metadata and corresponding nativeTest related unit tests apache/shardingsphere#29052 .

Would you like to help contributing this feature?

No

[eddumelendez]

H @linghengqian, thanks for the suggestion. You can use JUnit 5 @AutoClose extension along with Network, Container classes must be annotated as well.

@AutoClose
private static final Network network = Network.newNetwork();

@Container
@AutoClose
private static final PostgreSQLContainer<?> postgres = new PostgreSQLContainer<>("postgres:15-alpine")
	.withNetwork(network)
	.withNetworkAliases("postgres");

@Container
@AutoClose
private static final ToxiproxyContainer toxiproxy = new ToxiproxyContainer("ghcr.io/shopify/toxiproxy:2.9.0")
	.withNetwork(network);

[linghengqian]

@eddumelendez Thanks for the clarification, I have verified this works at linghengqian/hive-server2-jdbc-driver#25 . Should I close the current issue?

[eddumelendez]

Glad to see it is working for you! I'm going to close this one for now.

[vlsi]

@eddumelendez , could you please clarify why would you recommend annotating containers with @AutoClose?
As far as I understand, TestcontainersExtension will anyway notify the container on the test finish, so @AutoClose looks excessive there.

At the same time, @AutoClose for Network is not documented. Do you think it is worth documenting?

Do you think it would be worth adding a Testcontainers-managed annotation like the following?

@Retention(RetentionPolicy.RUNTIME)
@AutoClose
@interface Network {
}

Then the users would have code like @Network Network =..., and Testcontainers could handle networks differently in the future without asking users to rewrite the tests.
For instance, if a special processing like "beforeAll" would be needed, @Network would enable Testcontainers to do so, however, if the users have just @AutoClose Network, then adding extra smarts in Testcontainers would be harder.

[vlsi]

@interface Network is a bad naming as there is no possibility to import two Network classes at the same time, so the code would be

    @org.testcontainers.junit.jupiter.Network
    public Network network = Network.newNetwork();

---

Well, @org.testcontainers.junit.jupiter.Container collides with import org.testcontainers.containers.Container;, and it would be great to resolve that conflict as well.