Add NATS example (#6230)

Demostrate how to use NATS along with GenericContainer.

Co-authored-by: Krzysztof Kocel <[email protected]>

Author: eddumelendez

docs/examples.md

@@ -16,3 +16,4 @@ Examples of different use cases provided by Testcontainers can be found below:
 - [TestNG](https://github.com/testcontainers/testcontainers-java/tree/main/examples/redis-backed-cache-testng)
 - [ImmuDb](https://github.com/testcontainers/testcontainers-java/tree/main/examples/immudb)
 - [Zookeeper](https://github.com/testcontainers/testcontainers-java/tree/main/examples/zookeeper)
+- [NATS](https://github.com/testcontainers/testcontainers-java/tree/main/examples/nats)

examples/nats/build.gradle

@@ -0,0 +1,15 @@
+plugins {
+    id 'java'
+}
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    testImplementation 'org.assertj:assertj-core:3.23.1'
+    testImplementation 'org.testcontainers:testcontainers'
+    testImplementation 'io.nats:jnats:2.16.4'
+    testImplementation 'ch.qos.logback:logback-classic:1.3.4'
+    testImplementation 'org.apache.httpcomponents:httpclient:4.5.13'
+}

examples/nats/src/test/java/com/example/NatsContainerTest.java

@@ -0,0 +1,56 @@
+package com.example;
+
+import io.nats.client.Connection;
+import io.nats.client.Nats;
+import io.nats.client.Options;
+import org.apache.http.HttpResponse;
+import org.apache.http.HttpStatus;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.client.methods.HttpUriRequest;
+import org.apache.http.impl.client.HttpClientBuilder;
+import org.junit.Test;
+import org.testcontainers.containers.GenericContainer;
+
+import java.io.IOException;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class NatsContainerTest {
+
+    public static final Integer NATS_PORT = 4222;
+
+    public static final Integer NATS_MGMT_PORT = 8222;
+
+    @Test
+    public void test() throws IOException, InterruptedException {
+        try (
+            GenericContainer<?> nats = new GenericContainer<>("nats:2.9.8-alpine3.16")
+                .withExposedPorts(NATS_PORT, NATS_MGMT_PORT)
+        ) {
+            nats.start();
+
+            Connection connection = Nats.connect(
+                new Options.Builder().server("nats://" + nats.getHost() + ":" + nats.getMappedPort(NATS_PORT)).build()
+            );
+
+            assertThat(connection.getStatus()).isEqualTo(Connection.Status.CONNECTED);
+        }
+    }
+
+    @Test
+    public void testServerStatus() throws IOException {
+        try (
+            GenericContainer<?> nats = new GenericContainer<>("nats:2.9.8-alpine3.16")
+                .withExposedPorts(NATS_PORT, NATS_MGMT_PORT)
+        ) {
+            nats.start();
+
+            HttpUriRequest request = new HttpGet(
+                String.format("http://%s:%d/varz", nats.getHost(), nats.getMappedPort(NATS_MGMT_PORT))
+            );
+            HttpResponse httpResponse = HttpClientBuilder.create().build().execute(request);
+
+            assertThat(httpResponse.getStatusLine().getStatusCode()).isEqualTo(HttpStatus.SC_OK);
+        }
+    }
+}

examples/nats/src/test/resources/logback-test.xml

@@ -0,0 +1,16 @@
+<configuration>
+
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <!-- encoders are assigned the type
+             ch.qos.logback.classic.encoder.PatternLayoutEncoder by default -->
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} %-5level %logger - %msg%n</pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT"/>
+    </root>
+
+    <logger name="org.testcontainers" level="INFO"/>
+</configuration>

examples/settings.gradle

@@ -33,6 +33,7 @@ include 'spring-boot-kotlin-redis'
 include 'immudb'
 include 'zookeeper'
 include 'hazelcast'
+include 'nats'
 
 ext.isCI = System.getenv("CI") != null