adding actuator health check support for Elasticsearch REST Clients

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

@@ -263,6 +263,11 @@
 			<artifactId>elasticsearch</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>org.elasticsearch.client</groupId>
+			<artifactId>elasticsearch-rest-high-level-client</artifactId>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 			<groupId>org.eclipse.jetty</groupId>
 			<artifactId>jetty-server</artifactId>

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/elasticsearch/ElasticSearchRestHealthIndicatorAutoConfiguration.java

@@ -0,0 +1,75 @@
+/*
+ * Copyright 2012-2018 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.actuate.autoconfigure.elasticsearch;
+
+import java.util.Map;
+
+import org.elasticsearch.client.RestHighLevelClient;
+
+import org.springframework.boot.actuate.autoconfigure.health.CompositeHealthIndicatorConfiguration;
+import org.springframework.boot.actuate.autoconfigure.health.ConditionalOnEnabledHealthIndicator;
+import org.springframework.boot.actuate.autoconfigure.health.HealthIndicatorAutoConfiguration;
+import org.springframework.boot.actuate.elasticsearch.ElasticsearchRestHealthIndicator;
+import org.springframework.boot.actuate.health.HealthIndicator;
+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.elasticsearch.rest.RestClientAutoConfiguration;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * {@link EnableAutoConfiguration Auto-configuration} for
+ * {@link ElasticsearchRestHealthIndicator} using the {@link RestHighLevelClient}.
+ *
+ * @author Artsiom Yudovin
+ * @since 2.1.0
+ */
+
+@Configuration
+@ConditionalOnClass(RestHighLevelClient.class)
+@ConditionalOnBean(RestHighLevelClient.class)
+@ConditionalOnEnabledHealthIndicator("elasticsearch")
+@AutoConfigureBefore(HealthIndicatorAutoConfiguration.class)
+@AutoConfigureAfter({ RestClientAutoConfiguration.class,
+		ElasticSearchClientHealthIndicatorAutoConfiguration.class })
+public class ElasticSearchRestHealthIndicatorAutoConfiguration extends
+		CompositeHealthIndicatorConfiguration<ElasticsearchRestHealthIndicator, RestHighLevelClient> {
+
+	private final Map<String, RestHighLevelClient> clients;
+
+	public ElasticSearchRestHealthIndicatorAutoConfiguration(
+			Map<String, RestHighLevelClient> clients) {
+		this.clients = clients;
+	}
+
+	@Bean
+	@ConditionalOnMissingBean(name = "elasticsearchRestHealthIndicator")
+	public HealthIndicator elasticsearchRestHealthIndicator() {
+		return createHealthIndicator(this.clients);
+	}
+
+	@Override
+	protected ElasticsearchRestHealthIndicator createHealthIndicator(
+			RestHighLevelClient client) {
+		return new ElasticsearchRestHealthIndicator(client);
+	}
+
+}

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

@@ -77,6 +77,11 @@
 			<artifactId>jest</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>org.elasticsearch.client</groupId>
+			<artifactId>elasticsearch-rest-high-level-client</artifactId>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 			<groupId>io.undertow</groupId>
 			<artifactId>undertow-servlet</artifactId>

spring-boot-project/spring-boot-actuator/src/main/java/org/springframework/boot/actuate/elasticsearch/ElasticsearchRestHealthIndicator.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2012-2018 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.actuate.elasticsearch;
+
+import org.elasticsearch.action.main.MainResponse;
+import org.elasticsearch.client.RequestOptions;
+import org.elasticsearch.client.RestHighLevelClient;
+
+import org.springframework.boot.actuate.health.AbstractHealthIndicator;
+import org.springframework.boot.actuate.health.Health;
+import org.springframework.boot.actuate.health.HealthIndicator;
+
+/**
+ * {@link HealthIndicator} for an Elasticsearch cluster by REST.
+ *
+ * @author Artsiom Yudovin
+ * @since 2.1.0
+ */
+public class ElasticsearchRestHealthIndicator extends AbstractHealthIndicator {
+
+	private final RestHighLevelClient client;
+
+	public ElasticsearchRestHealthIndicator(RestHighLevelClient client) {
+		super("Elasticsearch health check failed");
+		this.client = client;
+	}
+
+	@Override
+	protected void doHealthCheck(Health.Builder builder) throws Exception {
+		MainResponse info = this.client.info(RequestOptions.DEFAULT);
+
+		if (info.isAvailable()) {
+			builder.up();
+		}
+		else {
+			builder.down();
+		}
+
+		builder.withDetail("clusterName", info.getClusterName());
+		builder.withDetail("nodeName", info.getNodeName());
+		builder.withDetail("clusterUuid", info.getClusterUuid());
+		builder.withDetail("version", info.getVersion());
+	}
+
+}