Polish "Add Kafka health indicator"

Closes gh-11515

spring-boot-project/spring-boot-actuator-autoconfigure/pom.xml

@@ -193,11 +193,6 @@
 			<artifactId>elasticsearch</artifactId>
 			<optional>true</optional>
 		</dependency>
-		<dependency>
-			<groupId>org.springframework.kafka</groupId>
-			<artifactId>spring-kafka</artifactId>
-			<optional>true</optional>
-		</dependency>
 		<dependency>
 			<groupId>org.flywaydb</groupId>
 			<artifactId>flyway-core</artifactId>
@@ -311,6 +306,11 @@
 			<artifactId>spring-integration-core</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>org.springframework.kafka</groupId>
+			<artifactId>spring-kafka</artifactId>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework.security</groupId>
 			<artifactId>spring-security-config</artifactId>

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/kafka/KafkaHealthIndicatorAutoConfiguration.java

@@ -28,6 +28,7 @@ import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.boot.autoconfigure.AutoConfigureBefore;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.kafka.KafkaAutoConfiguration;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
@@ -41,40 +42,35 @@ import org.springframework.kafka.core.KafkaAdmin;
  * @author Juan Rada
  */
 @Configuration
+@ConditionalOnClass(KafkaAdmin.class)
+@ConditionalOnBean(KafkaAdmin.class)
 @ConditionalOnEnabledHealthIndicator("kafka")
 @AutoConfigureBefore(HealthIndicatorAutoConfiguration.class)
 @AutoConfigureAfter(KafkaAutoConfiguration.class)
-public class KafkaHealthIndicatorAutoConfiguration {
+@EnableConfigurationProperties(KafkaHealthIndicatorProperties.class)
+public class KafkaHealthIndicatorAutoConfiguration extends
+		CompositeHealthIndicatorConfiguration<KafkaHealthIndicator, KafkaAdmin> {
 
-	@Configuration
-	@ConditionalOnBean(KafkaAdmin.class)
-	@EnableConfigurationProperties(KafkaHealthIndicatorProperties.class)
-	static class KafkaClientHealthIndicatorConfiguration extends
-			CompositeHealthIndicatorConfiguration<KafkaHealthIndicator, KafkaAdmin> {
+	private final Map<String, KafkaAdmin> admins;
 
-		private final Map<String, KafkaAdmin> admins;
+	private final KafkaHealthIndicatorProperties properties;
 
-		private final KafkaHealthIndicatorProperties properties;
-
-		KafkaClientHealthIndicatorConfiguration(Map<String, KafkaAdmin> admins,
-				KafkaHealthIndicatorProperties properties) {
-			this.admins = admins;
-			this.properties = properties;
-		}
-
-		@Bean
-		@ConditionalOnMissingBean(name = "kafkaHealthIndicator")
-		public HealthIndicator kafkaHealthIndicator() {
-			return createHealthIndicator(this.admins);
-		}
+	KafkaHealthIndicatorAutoConfiguration(Map<String, KafkaAdmin> admins,
+			KafkaHealthIndicatorProperties properties) {
+		this.admins = admins;
+		this.properties = properties;
+	}
 
-		@Override
-		protected KafkaHealthIndicator createHealthIndicator(KafkaAdmin source) {
-			Duration responseTimeout = this.properties.getResponseTimeout();
+	@Bean
+	@ConditionalOnMissingBean(name = "kafkaHealthIndicator")
+	public HealthIndicator kafkaHealthIndicator() {
+		return createHealthIndicator(this.admins);
+	}
 
-			return new KafkaHealthIndicator(source,
-					responseTimeout == null ? 100L : responseTimeout.toMillis());
-		}
+	@Override
+	protected KafkaHealthIndicator createHealthIndicator(KafkaAdmin source) {
+		Duration responseTimeout = this.properties.getResponseTimeout();
+		return new KafkaHealthIndicator(source, responseTimeout.toMillis());
 	}
 
 }

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/kafka/KafkaHealthIndicatorProperties.java

@@ -25,6 +25,7 @@ import org.springframework.boot.context.properties.ConfigurationProperties;
  * Configuration properties for {@link KafkaHealthIndicator}.
  *
  * @author Juan Rada
+ * @since 2.0.0
  */
 @ConfigurationProperties(prefix = "management.health.kafka", ignoreUnknownFields = false)
 public class KafkaHealthIndicatorProperties {
@@ -32,7 +33,7 @@ public class KafkaHealthIndicatorProperties {
 	/**
 	 * Time to wait for a response from the cluster description operation.
 	 */
-	private Duration responseTimeout = Duration.ofMillis(100);
+	private Duration responseTimeout = Duration.ofMillis(1000);
 
 	public Duration getResponseTimeout() {
 		return this.responseTimeout;

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/kafka/package-info.java

@@ -15,6 +15,6 @@
  */
 
 /**
- * Auto-configuration for actuator kafka support.
+ * Auto-configuration for actuator Apache Kafka support.
  */
 package org.springframework.boot.actuate.autoconfigure.kafka;

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -103,6 +103,12 @@
       "description": "Whether to enable JMS health check.",
       "defaultValue": true
     },
+    {
+      "name": "management.health.kafka.enabled",
+      "type": "java.lang.Boolean",
+      "description": "Whether to enable Kafka health check.",
+      "defaultValue": true
+    },
     {
       "name": "management.health.ldap.enabled",
       "type": "java.lang.Boolean",
@@ -145,12 +151,6 @@
       "description": "Whether to enable Neo4j health check.",
       "defaultValue": true
     },
-    {
-      "name": "management.health.kafka.enabled",
-      "type": "java.lang.Boolean",
-      "description": "Whether to enable kafka health check.",
-      "defaultValue": true
-    },
     {
       "name": "management.info.build.enabled",
       "type": "java.lang.Boolean",

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/resources/META-INF/spring.factories

@@ -11,7 +11,6 @@ org.springframework.boot.actuate.autoconfigure.context.properties.ConfigurationP
 org.springframework.boot.actuate.autoconfigure.context.ShutdownEndpointAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.couchbase.CouchbaseHealthIndicatorAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.elasticsearch.ElasticsearchHealthIndicatorAutoConfiguration,\
-org.springframework.boot.actuate.autoconfigure.kafka.KafkaHealthIndicatorAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.endpoint.EndpointAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.endpoint.jmx.JmxEndpointAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.endpoint.web.WebEndpointAutoConfiguration,\
@@ -25,6 +24,7 @@ org.springframework.boot.actuate.autoconfigure.info.InfoEndpointAutoConfiguratio
 org.springframework.boot.actuate.autoconfigure.jdbc.DataSourceHealthIndicatorAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.jms.JmsHealthIndicatorAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.jolokia.JolokiaEndpointAutoConfiguration,\
+org.springframework.boot.actuate.autoconfigure.kafka.KafkaHealthIndicatorAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.ldap.LdapHealthIndicatorAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.liquibase.LiquibaseEndpointAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.logging.LogFileWebEndpointAutoConfiguration,\

spring-boot-project/spring-boot-actuator/pom.xml

@@ -172,11 +172,6 @@
 			<artifactId>spring-rabbit</artifactId>
 			<optional>true</optional>
 		</dependency>
-		<dependency>
-			<groupId>org.springframework.kafka</groupId>
-			<artifactId>spring-kafka</artifactId>
-			<optional>true</optional>
-		</dependency>
 		<dependency>
 			<groupId>org.springframework.data</groupId>
 			<artifactId>spring-data-cassandra</artifactId>
@@ -230,6 +225,11 @@
 			<artifactId>spring-integration-core</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>org.springframework.kafka</groupId>
+			<artifactId>spring-kafka</artifactId>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework.security</groupId>
 			<artifactId>spring-security-core</artifactId>
@@ -263,13 +263,13 @@
 			<scope>test</scope>
 		</dependency>
 		<dependency>
-			<groupId>org.springframework.kafka</groupId>
-			<artifactId>spring-kafka-test</artifactId>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-autoconfigure</artifactId>
 			<scope>test</scope>
 		</dependency>
 		<dependency>
-			<groupId>org.springframework.boot</groupId>
-			<artifactId>spring-boot-autoconfigure</artifactId>
+			<groupId>org.springframework.kafka</groupId>
+			<artifactId>spring-kafka-test</artifactId>
 			<scope>test</scope>
 		</dependency>
 		<dependency>

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/kafka/KafkaHealthIndicator.java

@@ -30,6 +30,7 @@ import org.apache.kafka.common.config.ConfigResource.Type;
 import org.springframework.boot.actuate.health.AbstractHealthIndicator;
 import org.springframework.boot.actuate.health.Health.Builder;
 import org.springframework.boot.actuate.health.HealthIndicator;
+import org.springframework.boot.actuate.health.Status;
 import org.springframework.kafka.core.KafkaAdmin;
 import org.springframework.util.Assert;
 
@@ -43,37 +44,35 @@ public class KafkaHealthIndicator extends AbstractHealthIndicator {
 	static final String REPLICATION_PROPERTY = "transaction.state.log.replication.factor";
 
 	private final KafkaAdmin kafkaAdmin;
+
 	private final DescribeClusterOptions describeOptions;
 
 	/**
 	 * Create a new {@link KafkaHealthIndicator} instance.
 	 *
 	 * @param kafkaAdmin the kafka admin
-	 * @param responseTimeout the describe cluster request timeout in milliseconds
+	 * @param requestTimeout the request timeout in milliseconds
 	 */
-	public KafkaHealthIndicator(KafkaAdmin kafkaAdmin, long responseTimeout) {
+	public KafkaHealthIndicator(KafkaAdmin kafkaAdmin, long requestTimeout) {
 		Assert.notNull(kafkaAdmin, "KafkaAdmin must not be null");
 		this.kafkaAdmin = kafkaAdmin;
 		this.describeOptions = new DescribeClusterOptions()
-				.timeoutMs((int) responseTimeout);
+				.timeoutMs((int) requestTimeout);
 	}
 
 	@Override
 	protected void doHealthCheck(Builder builder) throws Exception {
 		try (AdminClient adminClient = AdminClient.create(this.kafkaAdmin.getConfig())) {
-			DescribeClusterResult result = adminClient.describeCluster(this.describeOptions);
+			DescribeClusterResult result = adminClient.describeCluster(
+					this.describeOptions);
 			String brokerId = result.controller().get().idString();
 			int replicationFactor = getReplicationFactor(brokerId, adminClient);
 			int nodes = result.nodes().get().size();
-			if (nodes >= replicationFactor) {
-				builder.up();
-			}
-			else {
-				builder.down();
-			}
-			builder.withDetail("clusterId", result.clusterId().get());
-			builder.withDetail("brokerId", brokerId);
-			builder.withDetail("nodes", nodes);
+			Status status = nodes >= replicationFactor ? Status.UP : Status.DOWN;
+			builder.status(status)
+					.withDetail("clusterId", result.clusterId().get())
+					.withDetail("brokerId", brokerId)
+					.withDetail("nodes", nodes);
 		}
 	}
 
@@ -85,5 +84,6 @@ public class KafkaHealthIndicator extends AbstractHealthIndicator {
 		Config brokerConfig = kafkaConfig.get(configResource);
 		return Integer.parseInt(brokerConfig.get(REPLICATION_PROPERTY).value());
 	}
+
 }
 

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/kafka/package-info.java

@@ -15,6 +15,6 @@
  */
 
 /**
- * Actuator support for Kafka.
+ * Actuator support for Apache Kafka.
  */
 package org.springframework.boot.actuate.kafka;

spring-boot-project/spring-boot-actuator/src/test/java/org/springframework/boot/actuate/kafka/KafkaHealthIndicatorTests.java

@@ -20,78 +20,82 @@ import java.util.Collections;
 import java.util.Map;
 
 import org.apache.kafka.clients.producer.ProducerConfig;
+import org.junit.After;
 import org.junit.Test;
 
 import org.springframework.boot.actuate.health.Health;
 import org.springframework.boot.actuate.health.Status;
 import org.springframework.kafka.core.KafkaAdmin;
 import org.springframework.kafka.test.rule.KafkaEmbedded;
+import org.springframework.util.SocketUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
 /**
- * Test for {@link KafkaHealthIndicator}
+ * Tests for {@link KafkaHealthIndicator}.
  *
  * @author Juan Rada
+ * @author Stephane Nicoll
  */
 public class KafkaHealthIndicatorTests {
 
-	private static final Long RESPONSE_TIME = 1000L;
-
 	private KafkaEmbedded kafkaEmbedded;
-	private KafkaAdmin kafkaAdmin;
 
-	private void startKafka(int replicationFactor) throws Exception {
-		this.kafkaEmbedded = new KafkaEmbedded(1, true);
-		this.kafkaEmbedded.brokerProperties(Collections.singletonMap(
-				KafkaHealthIndicator.REPLICATION_PROPERTY,
-				String.valueOf(replicationFactor)));
-		this.kafkaEmbedded.before();
-		this.kafkaAdmin = new KafkaAdmin(Collections.singletonMap(
-				ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,
-				this.kafkaEmbedded.getBrokersAsString()));
-	}
+	private KafkaAdmin kafkaAdmin;
 
-	private void shutdownKafka() throws Exception {
-		this.kafkaEmbedded.destroy();
+	@After
+	public void shutdownKafka() throws Exception {
+		if (this.kafkaEmbedded != null) {
+			this.kafkaEmbedded.destroy();
+		}
 	}
-
 	@Test
 	public void kafkaIsUp() throws Exception {
 		startKafka(1);
 		KafkaHealthIndicator healthIndicator =
-				new KafkaHealthIndicator(this.kafkaAdmin, RESPONSE_TIME);
+				new KafkaHealthIndicator(this.kafkaAdmin, 1000L);
 		Health health = healthIndicator.health();
 		assertThat(health.getStatus()).isEqualTo(Status.UP);
 		assertDetails(health.getDetails());
-		shutdownKafka();
 	}
 
-	private void assertDetails(Map<String, Object> details) {
-		assertThat(details).containsEntry("brokerId", "0");
-		assertThat(details).containsKey("clusterId");
-		assertThat(details).containsEntry("nodes", 1);
+	@Test
+	public void kafkaIsDown() {
+		int freePort = SocketUtils.findAvailableTcpPort();
+		this.kafkaAdmin = new KafkaAdmin(Collections.singletonMap(
+				ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "127.0.0.1:" + freePort));
+		KafkaHealthIndicator healthIndicator =
+				new KafkaHealthIndicator(this.kafkaAdmin, 1L);
+		Health health = healthIndicator.health();
+		assertThat(health.getStatus()).isEqualTo(Status.DOWN);
+		assertThat((String) health.getDetails().get("error")).isNotEmpty();
 	}
 
 	@Test
 	public void notEnoughNodesForReplicationFactor() throws Exception {
 		startKafka(2);
 		KafkaHealthIndicator healthIndicator =
-				new KafkaHealthIndicator(this.kafkaAdmin, RESPONSE_TIME);
+				new KafkaHealthIndicator(this.kafkaAdmin, 1000L);
 		Health health = healthIndicator.health();
 		assertThat(health.getStatus()).isEqualTo(Status.DOWN);
 		assertDetails(health.getDetails());
-		shutdownKafka();
 	}
 
-	@Test
-	public void kafkaIsDown() throws Exception {
+	private void assertDetails(Map<String, Object> details) {
+		assertThat(details).containsEntry("brokerId", "0");
+		assertThat(details).containsKey("clusterId");
+		assertThat(details).containsEntry("nodes", 1);
+	}
+
+	private void startKafka(int replicationFactor) throws Exception {
+		this.kafkaEmbedded = new KafkaEmbedded(1, true);
+		this.kafkaEmbedded.brokerProperties(Collections.singletonMap(
+				KafkaHealthIndicator.REPLICATION_PROPERTY,
+				String.valueOf(replicationFactor)));
+		this.kafkaEmbedded.before();
 		this.kafkaAdmin = new KafkaAdmin(Collections.singletonMap(
-				ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "127.0.0.1:34987"));
-		KafkaHealthIndicator healthIndicator =
-				new KafkaHealthIndicator(this.kafkaAdmin, RESPONSE_TIME);
-		Health health = healthIndicator.health();
-		assertThat(health.getStatus()).isEqualTo(Status.DOWN);
-		assertThat((String) health.getDetails().get("error")).isNotEmpty();
+				ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,
+				this.kafkaEmbedded.getBrokersAsString()));
 	}
+
 }

spring-boot-project/spring-boot-docs/src/main/asciidoc/appendix-application-properties.adoc

@@ -1271,6 +1271,8 @@ content into your application. Rather, pick only the properties that you need.
 	management.health.elasticsearch.response-timeout=100ms # The time to wait for a response from the cluster.
 	management.health.influxdb.enabled=true # Whether to enable InfluxDB health check.
 	management.health.jms.enabled=true # Whether to enable JMS health check.
+	management.health.kafka.enabled=true # Whether to enable Kafka health check.
+	management.health.kafka.response-timeout=1000ms # Time to wait for a response from the cluster description operation.
 	management.health.ldap.enabled=true # Whether to enable LDAP health check.
 	management.health.mail.enabled=true # Whether to enable Mail health check.
 	management.health.mongo.enabled=true # Whether to enable MongoDB health check.

spring-boot-project/spring-boot-docs/src/main/asciidoc/production-ready-features.adoc

@@ -572,6 +572,9 @@ The following `HealthIndicators` are auto-configured by Spring Boot when appropr
 |{sc-spring-boot-actuator}/jms/JmsHealthIndicator.{sc-ext}[`JmsHealthIndicator`]
 |Checks that a JMS broker is up.
 
+|{sc-spring-boot-actuator}/kafka/KafkaHealthIndicator.{sc-ext}[`KafkaHealthIndicator`]
+|Checks that a Kafka server is up.
+
 |{sc-spring-boot-actuator}/mail/MailHealthIndicator.{sc-ext}[`MailHealthIndicator`]
 |Checks that a mail server is up.