From 23cde30063329beb76395a121d41800d0decaccc Mon Sep 17 00:00:00 2001
From: Dave Syer <dsyer@pivotal.io>
Date: Tue, 2 Jun 2015 15:27:39 +0100
Subject: [PATCH] Align metrics with Spring Boot 1.3

Should be no change for users of Boot 1.2 right now, but with this
patch it is possible to use 1.3 with the new conventions for metrics
(e.g. in particular exporting by declaring beans of type
MetricWriter)
---
 .../EurekaDiscoveryClientConfiguration.java   | 11 ++++--
 .../servo/ServoMetricsAutoConfiguration.java  | 36 ++++++++++++++++---
 2 files changed, 41 insertions(+), 6 deletions(-)

diff --git a/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka/EurekaDiscoveryClientConfiguration.java b/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka/EurekaDiscoveryClientConfiguration.java
index 1a58bb5b..05732cf1 100644
--- a/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka/EurekaDiscoveryClientConfiguration.java
+++ b/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka/EurekaDiscoveryClientConfiguration.java
@@ -17,6 +17,8 @@
 package org.springframework.cloud.netflix.eureka;
 
 import java.lang.reflect.Field;
+import java.util.Collections;
+import java.util.List;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 
@@ -26,6 +28,7 @@ import lombok.extern.apachecommons.CommonsLog;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.actuate.endpoint.Endpoint;
+import org.springframework.boot.actuate.metrics.reader.CompositeMetricReader;
 import org.springframework.boot.actuate.metrics.reader.MetricReader;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
@@ -220,11 +223,15 @@ public class EurekaDiscoveryClientConfiguration implements SmartLifecycle, Order
 	@ConditionalOnClass(Endpoint.class)
 	@ConditionalOnBean(MetricReader.class)
 	protected static class EurekaHealthIndicatorConfiguration {
+		
+		@Autowired
+		private List<MetricReader> metricReaders = Collections.emptyList();
+		
 		@Bean
 		@ConditionalOnMissingBean
 		public EurekaHealthIndicator eurekaHealthIndicator(
-				com.netflix.discovery.DiscoveryClient eurekaDiscoveryClient,
-				MetricReader metrics, EurekaInstanceConfig config) {
+				com.netflix.discovery.DiscoveryClient eurekaDiscoveryClient, EurekaInstanceConfig config) {
+			CompositeMetricReader metrics = new CompositeMetricReader(metricReaders.toArray(new MetricReader[0]));
 			return new EurekaHealthIndicator(eurekaDiscoveryClient, metrics, config);
 		}
 	}
diff --git a/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/servo/ServoMetricsAutoConfiguration.java b/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/servo/ServoMetricsAutoConfiguration.java
index 52eac58d..e60ac1af 100644
--- a/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/servo/ServoMetricsAutoConfiguration.java
+++ b/spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/servo/ServoMetricsAutoConfiguration.java
@@ -18,7 +18,10 @@ package org.springframework.cloud.netflix.servo;
 
 import org.springframework.boot.actuate.autoconfigure.EndpointAutoConfiguration;
 import org.springframework.boot.actuate.autoconfigure.MetricRepositoryAutoConfiguration;
+import org.springframework.boot.actuate.metrics.GaugeService;
+import org.springframework.boot.actuate.metrics.Metric;
 import org.springframework.boot.actuate.metrics.reader.MetricReader;
+import org.springframework.boot.actuate.metrics.writer.Delta;
 import org.springframework.boot.actuate.metrics.writer.MetricWriter;
 import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.boot.autoconfigure.AutoConfigureBefore;
@@ -38,7 +41,7 @@ import com.netflix.servo.monitor.Monitors;
  */
 @Configuration
 @ConditionalOnClass({ Monitors.class, MetricReader.class })
-@ConditionalOnBean(MetricReader.class)
+@ConditionalOnBean(GaugeService.class)
 @AutoConfigureBefore(EndpointAutoConfiguration.class)
 @AutoConfigureAfter({ MetricRepositoryAutoConfiguration.class })
 public class ServoMetricsAutoConfiguration {
@@ -51,9 +54,34 @@ public class ServoMetricsAutoConfiguration {
 
 	@Bean
 	@ConditionalOnMissingBean
-	public ServoMetricCollector servoMetricCollector(MetricWriter metrics,
-													 ServoMetricNaming naming) {
-		return new ServoMetricCollector(metrics, naming);
+	public ServoMetricCollector servoMetricCollector(GaugeService gauges,
+			ServoMetricNaming naming) {
+		return new ServoMetricCollector(new ActuatorMetricWriter(gauges), naming);
+	}
+
+	// TODO: refactor this when Spring Boot 1.3 is mandatory
+	private static class ActuatorMetricWriter implements MetricWriter {
+
+		private GaugeService gauges;
+
+		public ActuatorMetricWriter(GaugeService gauges) {
+			this.gauges = gauges;
+		}
+
+		@Override
+		public void increment(Delta<?> delta) {
+		}
+
+		@Override
+		public void set(Metric<?> value) {
+			gauges.submit(value.getName(), value.getValue().doubleValue());
+		}
+
+		@Override
+		public void reset(String metricName) {
+			gauges.submit(metricName, 0.);
+		}
+
 	}
 
 }