Add test containers

pom.xml

@@ -17,6 +17,7 @@
         <additionalOptions>-Xdoclint:none</additionalOptions>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <protobuf.version>3.11.1</protobuf.version>
+        <testcontainers.version>1.14.3</testcontainers.version>
     </properties>
 
     <scm>
@@ -177,6 +178,34 @@
             <version>4.12</version>
             <scope>test</scope>
         </dependency>
+
+        <!-- Spring test -->
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.junit.vintage</groupId>
+                    <artifactId>junit-vintage-engine</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+
+        <!-- Testcontainers -->
+        <dependency>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>testcontainers</artifactId>
+            <version>${testcontainers.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>kafka</artifactId>
+            <version>${testcontainers.version}</version>
+            <scope>test</scope>
+        </dependency>
+
     </dependencies>
 
     <build>

src/main/java/kafdrop/Kafdrop.java

@@ -46,13 +46,17 @@ public class Kafdrop {
   private final static Logger LOG = LoggerFactory.getLogger(Kafdrop.class);
 
   public static void main(String[] args) {
-    new SpringApplicationBuilder(Kafdrop.class)
-        .bannerMode(Mode.OFF)
-        .listeners(new EnvironmentSetupListener(),
-                   new LoggingConfigurationListener())
-        .run(args);
+    createApplicationBuilder()
+      .run(args);
   }
-
+
+  public static SpringApplicationBuilder createApplicationBuilder() {
+    return new SpringApplicationBuilder(Kafdrop.class)
+      .bannerMode(Mode.OFF)
+      .listeners(new EnvironmentSetupListener(),
+              new LoggingConfigurationListener());
+  }
+
   @Bean
   public WebServerFactoryCustomizer<UndertowServletWebServerFactory> deploymentCustomizer() {
     return factory -> {

src/test/java/kafdrop/AbstractIntegrationTest.java

@@ -0,0 +1,37 @@
+package kafdrop;
+
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.core.env.MapPropertySource;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.testcontainers.containers.KafkaContainer;
+import org.testcontainers.lifecycle.Startables;
+
+import java.util.List;
+import java.util.Map;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
+@ContextConfiguration(initializers = AbstractIntegrationTest.Initializer.class)
+abstract class AbstractIntegrationTest {
+    static class Initializer implements ApplicationContextInitializer<ConfigurableApplicationContext> {
+        static KafkaContainer kafka = new KafkaContainer();
+
+        public static Map<String, String> getProperties() {
+            Startables.deepStart(List.of(kafka)).join();
+            return Map.of("kafka.brokerConnect", kafka.getBootstrapServers());
+        }
+
+        @Override
+        @SuppressWarnings("unchecked, rawtypes")
+        public void initialize(ConfigurableApplicationContext context) {
+            var env = context.getEnvironment();
+            env.getPropertySources().addFirst(new MapPropertySource(
+                    "testcontainers", (Map) getProperties()
+            ));
+        }
+    }
+}

src/test/java/kafdrop/KafdropTest.java

@@ -0,0 +1,8 @@
+package kafdrop;
+
+import org.junit.Test;
+
+public class KafdropTest extends AbstractIntegrationTest {
+    @Test
+    public void contextTest(){}
+}

src/test/java/kafdrop/LocalRunner.java

@@ -0,0 +1,13 @@
+package kafdrop;
+
+/**
+ * Use this class for local development.
+ * It will run local kafka in docker with test containers.
+ */
+public class LocalRunner {
+    public static void main(String[] args) {
+        Kafdrop.createApplicationBuilder()
+                .initializers(new AbstractIntegrationTest.Initializer())
+                .run(args);
+    }
+}