Add metrics from Eureka client discovery

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka/EurekaClientConfiguration.java

@@ -16,13 +16,16 @@
 package org.springframework.cloud.netflix.eureka;
 
 import javax.annotation.PreDestroy;
+import javax.management.MBeanServer;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnExpression;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.cloud.netflix.servo.ServoMetricReader;
 import org.springframework.context.ApplicationListener;
 import org.springframework.context.SmartLifecycle;
 import org.springframework.context.annotation.Bean;
@@ -34,6 +37,7 @@ import org.springframework.context.event.ContextRefreshedEvent;
 import org.springframework.core.Ordered;
 
 import com.netflix.appinfo.ApplicationInfoManager;
+import com.netflix.appinfo.EurekaInstanceConfig;
 import com.netflix.appinfo.InstanceInfo.InstanceStatus;
 import com.netflix.discovery.DiscoveryClient;
 import com.netflix.discovery.DiscoveryManager;
@@ -118,4 +122,10 @@ public class EurekaClientConfiguration implements
 		return DiscoveryManager.getInstance().getDiscoveryClient();
 	}
 	
+	@Bean
+	@ConditionalOnMissingBean
+	public EurekaHealthIndicator eurekaHealthIndicator(MBeanServer server, EurekaInstanceConfig config) {
+		return new EurekaHealthIndicator(discoveryClient(), new ServoMetricReader(server), config);
+	}
+	
 }

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka/EurekaHealthIndicator.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright 2013-2014 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.cloud.netflix.eureka;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.springframework.boot.actuate.health.Health;
+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.boot.actuate.metrics.Metric;
+import org.springframework.boot.actuate.metrics.reader.MetricReader;
+
+import com.netflix.appinfo.EurekaInstanceConfig;
+import com.netflix.discovery.DiscoveryClient;
+import com.netflix.discovery.shared.Application;
+import com.netflix.discovery.shared.Applications;
+
+/**
+ * @author Dave Syer
+ *
+ */
+public class EurekaHealthIndicator implements HealthIndicator {
+
+	private EurekaInstanceConfig instanceConfig;
+
+	private MetricReader metrics;
+
+	private int failCount = 0;
+
+	private DiscoveryClient discovery;
+
+	public EurekaHealthIndicator(DiscoveryClient discovery, MetricReader metrics,
+			EurekaInstanceConfig instanceConfig) {
+		super();
+		this.discovery = discovery;
+		this.metrics = metrics;
+		this.instanceConfig = instanceConfig;
+	}
+
+	@Override
+	public Health health() {
+		Builder builder = Health.unknown();
+		Status status = getStatus(builder);
+		return builder.status(status).withDetail("applications", getApplications())
+				.build();
+	}
+
+	private Status getStatus(Builder builder) {
+		Status status = new Status(discovery.getInstanceRemoteStatus().toString(),
+				"Remote status from Eureka server");
+		@SuppressWarnings("unchecked")
+		Metric<Number> value = (Metric<Number>) metrics
+				.findOne("counter.servo.DiscoveryClient_Failed");
+		if (value != null) {
+			int renewalPeriod = instanceConfig.getLeaseRenewalIntervalInSeconds();
+			int latest = value.getValue().intValue();
+			builder.withDetail("failCount", latest);
+			builder.withDetail("renewalPeriod", renewalPeriod);
+			if (failCount < latest) {
+				status = new Status("UP", "Eureka discovery client is reporting failures");
+				failCount = latest;
+			} else {
+				status = new Status("UP", "No new failures in Eureka discovery client");				
+			}
+		}
+		return status;
+	}
+
+	private Map<String, Object> getApplications() {
+		Applications applications = discovery.getApplications();
+		if (applications == null) {
+			return Collections.emptyMap();
+		}
+		Map<String, Object> result = new HashMap<String, Object>();
+		for (Application application : applications.getRegisteredApplications()) {
+			result.put(application.getName(), application.getInstances().size());
+		}
+		return result;
+	}
+
+}

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/servo/ServoMetricReader.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2013-2014 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.cloud.netflix.servo;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+
+import javax.management.MBeanServer;
+import javax.management.ObjectInstance;
+import javax.management.ObjectName;
+
+import org.springframework.boot.actuate.metrics.Metric;
+import org.springframework.boot.actuate.metrics.reader.MetricReader;
+
+/**
+ * @author Dave Syer
+ *
+ */
+public class ServoMetricReader implements MetricReader {
+
+	private final MBeanServer server;
+
+	public ServoMetricReader(MBeanServer server) {
+		this.server = server;
+	}
+
+	@Override
+	public Metric<?> findOne(String metricName) {
+		return getServoMetrics().get(metricName);
+	}
+
+	@Override
+	public Iterable<Metric<?>> findAll() {
+		return getServoMetrics().values();
+	}
+
+	@Override
+	public long count() {
+		return getServoMetrics().size();
+	}
+	
+	private Map<String,Metric<?>> getServoMetrics() {
+		Map<String, Metric<?>> metrics = getServoMetrics("COUNTER");
+		metrics.putAll(getServoMetrics("GAUGE"));
+		return metrics;
+	}
+	
+	private Map<String,Metric<?>> getServoMetrics(String type) {
+		Map<String,Metric<?>> metrics = new HashMap<String, Metric<?>>();
+		try {
+			ObjectName name = new ObjectName("com.netflix.servo:type="+type+",*");
+			Set<ObjectInstance> beans = server.queryMBeans(name, null);
+			for (ObjectInstance bean : beans) {
+				// example: com.netflix.servo:name=DiscoveryClient_Failed,class=DiscoveryClient,type=COUNTER
+				String key = type.toLowerCase() + ".servo."
+						+ bean.getObjectName().getKeyProperty("name");
+				Object attribute = server.getAttribute(bean.getObjectName(), "value");
+				if (attribute instanceof Number) {
+					Number value = (Number) attribute;
+					metrics.put(key, new Metric<Number>(key, value));
+				}
+			}
+		}
+		catch (Exception e) {
+			// Really?
+		}
+		return metrics;
+	}
+
+}

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/servo/ServoMetricsAutoConfiguration.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2013-2014 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.cloud.netflix.servo;
+
+import javax.management.MBeanServer;
+
+import org.springframework.boot.actuate.autoconfigure.EndpointAutoConfiguration;
+import org.springframework.boot.actuate.autoconfigure.MetricRepositoryAutoConfiguration;
+import org.springframework.boot.actuate.metrics.reader.MetricReader;
+import org.springframework.boot.autoconfigure.AutoConfigureAfter;
+import org.springframework.boot.autoconfigure.AutoConfigureBefore;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import com.netflix.servo.monitor.Monitors;
+
+/**
+ * @author Dave Syer
+ *
+ */
+@Configuration
+@ConditionalOnClass({Monitors.class,MetricReader.class})
+@ConditionalOnBean({MBeanServer.class,MetricReader.class})
+@AutoConfigureBefore(EndpointAutoConfiguration.class)
+@AutoConfigureAfter(MetricRepositoryAutoConfiguration.class)
+public class ServoMetricsAutoConfiguration {
+	
+	@Bean
+	@ConditionalOnMissingBean
+	public ServoPublicMetrics servoPublicMetrics(MetricReader reader, MBeanServer server) {
+		return new ServoPublicMetrics(reader, server);
+	}
+
+}

spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/servo/ServoPublicMetrics.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2013-2014 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.cloud.netflix.servo;
+
+import java.util.Collection;
+
+import javax.management.MBeanServer;
+
+import org.springframework.boot.actuate.endpoint.VanillaPublicMetrics;
+import org.springframework.boot.actuate.metrics.Metric;
+import org.springframework.boot.actuate.metrics.reader.MetricReader;
+
+/**
+ * @author Dave Syer
+ *
+ */
+public class ServoPublicMetrics extends VanillaPublicMetrics {
+
+	private final ServoMetricReader servo;
+
+	public ServoPublicMetrics(MetricReader reader, MBeanServer server) {
+		super(reader);
+		this.servo = new ServoMetricReader(server);
+	}
+
+	@Override
+	public Collection<Metric<?>> metrics() {
+		Collection<Metric<?>> metrics = super.metrics();
+		if (servo != null) {
+			for (Metric<?> metric : servo.findAll()) {
+				metrics.add(metric);
+			}
+		}
+		return metrics;
+	}
+
+}

spring-cloud-netflix-core/src/main/resources/META-INF/spring.factories

@@ -1,3 +1,4 @@
 org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
 org.springframework.cloud.netflix.archaius.ArchaiusAutoConfiguration,\
-org.springframework.cloud.netflix.feign.FeignAutoConfiguration
+org.springframework.cloud.netflix.feign.FeignAutoConfiguration,\
+org.springframework.cloud.netflix.servo.ServoMetricsAutoConfiguration