feat: move junit4 integration to org.testcontainers:junit4 module

Previously, testcontainers declared an explicit dependency on JUnit4,
and this change decouples Testcontainers from JUnit4.

Note: JUnit4 is in maintenance mode, so it does not sound right to
force such a dependency.

The users who still need to use JUnit4 could use the following:

* Add org.testcontainers:junit4 dependency
* Add TestcontainersRule as follows:
  @rule TestcontainersRule<GenericContainer> = new TestcontainersRule(...)

Fixes #970

Author: vlsi

core/build.gradle

@@ -69,7 +69,6 @@ configurations.all {
 }
 
 dependencies {
-    api 'junit:junit:4.13.2'
     api 'org.slf4j:slf4j-api:1.7.36'
     compileOnly 'org.jetbrains:annotations:24.1.0'
     testCompileOnly 'org.jetbrains:annotations:24.1.0'
@@ -106,6 +105,8 @@ dependencies {
 
     shaded 'org.zeroturnaround:zt-exec:1.12'
 
+    testImplementation project(":junit4")
+    testImplementation 'junit:junit:4.13.2'
     testImplementation('com.google.cloud.tools:jib-core:0.23.0')  {
         exclude group: 'com.google.guava', module: 'guava'
     }

core/src/main/java/org/testcontainers/containers/ComposeContainer.java

@@ -5,8 +5,6 @@
 import lombok.NonNull;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.lang3.SystemUtils;
-import org.junit.runner.Description;
-import org.junit.runners.model.Statement;
 import org.testcontainers.containers.output.OutputFrame;
 import org.testcontainers.containers.wait.strategy.Wait;
 import org.testcontainers.containers.wait.strategy.WaitStrategy;
@@ -31,7 +29,7 @@
  * It uses either Compose V2 contained within the Docker binary, or a containerised version of Compose V2.
  */
 @Slf4j
-public class ComposeContainer extends FailureDetectingExternalResource implements Startable {
+public class ComposeContainer implements Startable {
 
     private final Map<String, Integer> scalingPreferences = new HashMap<>();
 
@@ -93,32 +91,6 @@ public ComposeContainer(String identifier, List<File> composeFiles) {
         this.project = this.composeDelegate.getProject();
     }
 
-    @Override
-    @Deprecated
-    public Statement apply(Statement base, Description description) {
-        return super.apply(base, description);
-    }
-
-    @Override
-    @Deprecated
-    public void starting(Description description) {
-        start();
-    }
-
-    @Override
-    @Deprecated
-    protected void succeeded(Description description) {}
-
-    @Override
-    @Deprecated
-    protected void failed(Throwable e, Description description) {}
-
-    @Override
-    @Deprecated
-    public void finished(Description description) {
-        stop();
-    }
-
     @Override
     public void start() {
         synchronized (MUTEX) {

core/src/main/java/org/testcontainers/containers/DockerComposeContainer.java

@@ -5,8 +5,6 @@
 import lombok.NonNull;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.lang3.SystemUtils;
-import org.junit.runner.Description;
-import org.junit.runners.model.Statement;
 import org.testcontainers.containers.output.OutputFrame;
 import org.testcontainers.containers.wait.strategy.Wait;
 import org.testcontainers.containers.wait.strategy.WaitStrategy;
@@ -30,9 +28,7 @@
  * Container which launches Docker Compose, for the purposes of launching a defined set of containers.
  */
 @Slf4j
-public class DockerComposeContainer<SELF extends DockerComposeContainer<SELF>>
-    extends FailureDetectingExternalResource
-    implements Startable {
+public class DockerComposeContainer<SELF extends DockerComposeContainer<SELF>> implements Startable {
 
     private final Map<String, Integer> scalingPreferences = new HashMap<>();
 
@@ -99,32 +95,6 @@ public DockerComposeContainer(String identifier, List<File> composeFiles) {
         this.project = this.composeDelegate.getProject();
     }
 
-    @Override
-    @Deprecated
-    public Statement apply(Statement base, Description description) {
-        return super.apply(base, description);
-    }
-
-    @Override
-    @Deprecated
-    public void starting(Description description) {
-        start();
-    }
-
-    @Override
-    @Deprecated
-    protected void succeeded(Description description) {}
-
-    @Override
-    @Deprecated
-    protected void failed(Throwable e, Description description) {}
-
-    @Override
-    @Deprecated
-    public void finished(Description description) {
-        stop();
-    }
-
     @Override
     public void start() {
         synchronized (MUTEX) {

core/src/main/java/org/testcontainers/containers/FailureDetectingExternalResource.java

@@ -32,8 +32,6 @@
 import org.apache.commons.lang3.SystemUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
-import org.junit.runner.Description;
-import org.junit.runners.model.Statement;
 import org.rnorth.ducttape.unreliables.Unreliables;
 import org.slf4j.Logger;
 import org.testcontainers.DockerClientFactory;
@@ -52,8 +50,6 @@
 import org.testcontainers.images.builder.Transferable;
 import org.testcontainers.lifecycle.Startable;
 import org.testcontainers.lifecycle.Startables;
-import org.testcontainers.lifecycle.TestDescription;
-import org.testcontainers.lifecycle.TestLifecycleAware;
 import org.testcontainers.utility.Base58;
 import org.testcontainers.utility.CommandLine;
 import org.testcontainers.utility.DockerImageName;
@@ -106,7 +102,6 @@
  */
 @Data
 public class GenericContainer<SELF extends GenericContainer<SELF>>
-    extends FailureDetectingExternalResource
     implements Container<SELF>, AutoCloseable, WaitStrategyTarget, Startable {
 
     public static final int CONTAINER_RUNNING_TIMEOUT_SEC = 30;
@@ -1053,57 +1048,6 @@ public void addExposedPorts(int... ports) {
         this.containerDef.addExposedTcpPorts(ports);
     }
 
-    private TestDescription toDescription(Description description) {
-        return new TestDescription() {
-            @Override
-            public String getTestId() {
-                return description.getDisplayName();
-            }
-
-            @Override
-            public String getFilesystemFriendlyName() {
-                return description.getClassName() + "-" + description.getMethodName();
-            }
-        };
-    }
-
-    @Override
-    @Deprecated
-    public Statement apply(Statement base, Description description) {
-        return super.apply(base, description);
-    }
-
-    @Override
-    @Deprecated
-    protected void starting(Description description) {
-        if (this instanceof TestLifecycleAware) {
-            ((TestLifecycleAware) this).beforeTest(toDescription(description));
-        }
-        this.start();
-    }
-
-    @Override
-    @Deprecated
-    protected void succeeded(Description description) {
-        if (this instanceof TestLifecycleAware) {
-            ((TestLifecycleAware) this).afterTest(toDescription(description), Optional.empty());
-        }
-    }
-
-    @Override
-    @Deprecated
-    protected void failed(Throwable e, Description description) {
-        if (this instanceof TestLifecycleAware) {
-            ((TestLifecycleAware) this).afterTest(toDescription(description), Optional.of(e));
-        }
-    }
-
-    @Override
-    @Deprecated
-    protected void finished(Description description) {
-        this.stop();
-    }
-
     /**
      * {@inheritDoc}
      */

core/src/main/java/org/testcontainers/containers/GenericContainer.java

@@ -4,8 +4,6 @@
 import lombok.Builder;
 import lombok.Getter;
 import lombok.Singular;
-import org.junit.rules.ExternalResource;
-import org.junit.rules.TestRule;
 import org.testcontainers.DockerClientFactory;
 import org.testcontainers.utility.ResourceReaper;
 
@@ -17,7 +15,7 @@
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.function.Consumer;
 
-public interface Network extends AutoCloseable, TestRule {
+public interface Network extends AutoCloseable {
     Network SHARED = new NetworkImpl(false, null, Collections.emptySet(), null) {
         @Override
         public void close() {
@@ -40,7 +38,7 @@ static NetworkImpl.NetworkImplBuilder builder() {
 
     @Builder
     @Getter
-    class NetworkImpl extends ExternalResource implements Network {
+    class NetworkImpl implements Network {
 
         private final String name = UUID.randomUUID().toString();
 
@@ -100,11 +98,6 @@ private String create() {
             return createNetworkCmd.exec().getId();
         }
 
-        @Override
-        protected void after() {
-            close();
-        }
-
         @Override
         public synchronized void close() {
             if (initialized.getAndSet(false)) {

core/src/main/java/org/testcontainers/containers/Network.java

@@ -7,8 +7,6 @@
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
-import org.junit.runner.Description;
-import org.junit.runners.model.Statement;
 import org.testcontainers.DockerClientFactory;
 import org.testcontainers.TestImages;
 import org.testcontainers.Testcontainers;
@@ -189,11 +187,6 @@ public String getId() {
 
             @Override
             public void close() {}
-
-            @Override
-            public Statement apply(Statement base, Description description) {
-                return null;
-            }
         };
 
         List<com.github.dockerjava.api.model.Network> networks = DockerClientFactory

core/src/test/java/org/testcontainers/containers/ExposedHostTest.java

@@ -6,6 +6,7 @@
 import org.junit.runner.RunWith;
 import org.testcontainers.DockerClientFactory;
 import org.testcontainers.TestImages;
+import org.testcontainers.junit4.TestcontainersRule;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -15,22 +16,24 @@ public class NetworkTest {
     public static class WithRules {
 
         @Rule
-        public Network network = Network.newNetwork();
+        public TestcontainersRule<Network> network = new TestcontainersRule<>(Network.newNetwork());
 
         @Rule
-        public GenericContainer<?> foo = new GenericContainer<>(TestImages.TINY_IMAGE)
-            .withNetwork(network)
-            .withNetworkAliases("foo")
-            .withCommand("/bin/sh", "-c", "while true ; do printf 'HTTP/1.1 200 OK\\n\\nyay' | nc -l -p 8080; done");
+        public TestcontainersRule<GenericContainer<?>> foo = new TestcontainersRule<>(
+            new GenericContainer<>(TestImages.TINY_IMAGE)
+                .withNetwork(network.get())
+                .withNetworkAliases("foo")
+                .withCommand("/bin/sh", "-c", "while true ; do printf 'HTTP/1.1 200 OK\\n\\nyay' | nc -l -p 8080; done")
+        );
 
         @Rule
-        public GenericContainer<?> bar = new GenericContainer<>(TestImages.TINY_IMAGE)
-            .withNetwork(network)
-            .withCommand("top");
+        public TestcontainersRule<GenericContainer<?>> bar = new TestcontainersRule<>(
+            new GenericContainer<>(TestImages.TINY_IMAGE).withNetwork(network.get()).withCommand("top")
+        );
 
         @Test
         public void testNetworkSupport() throws Exception {
-            String response = bar.execInContainer("wget", "-O", "-", "http://foo:8080").getStdout();
+            String response = bar.get().execInContainer("wget", "-O", "-", "http://foo:8080").getStdout();
             assertThat(response).as("received response").isEqualTo("yay");
         }
     }