Co-locate PublicMetrics auto-configuration

Fixes gh-1900

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/EndpointAutoConfiguration.java

@@ -18,6 +18,7 @@ package org.springframework.boot.actuate.autoconfigure;
 
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
@@ -34,18 +35,14 @@ import org.springframework.boot.actuate.endpoint.Endpoint;
 import org.springframework.boot.actuate.endpoint.EnvironmentEndpoint;
 import org.springframework.boot.actuate.endpoint.HealthEndpoint;
 import org.springframework.boot.actuate.endpoint.InfoEndpoint;
-import org.springframework.boot.actuate.endpoint.MetricReaderPublicMetrics;
 import org.springframework.boot.actuate.endpoint.MetricsEndpoint;
 import org.springframework.boot.actuate.endpoint.PublicMetrics;
 import org.springframework.boot.actuate.endpoint.RequestMappingEndpoint;
 import org.springframework.boot.actuate.endpoint.ShutdownEndpoint;
-import org.springframework.boot.actuate.endpoint.SystemPublicMetrics;
 import org.springframework.boot.actuate.endpoint.TraceEndpoint;
 import org.springframework.boot.actuate.health.HealthAggregator;
 import org.springframework.boot.actuate.health.HealthIndicator;
 import org.springframework.boot.actuate.health.OrderedHealthAggregator;
-import org.springframework.boot.actuate.metrics.reader.MetricReader;
-import org.springframework.boot.actuate.metrics.repository.InMemoryMetricRepository;
 import org.springframework.boot.actuate.trace.InMemoryTraceRepository;
 import org.springframework.boot.actuate.trace.TraceRepository;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
@@ -58,6 +55,7 @@ import org.springframework.boot.bind.PropertiesConfigurationFactory;
 import org.springframework.boot.context.properties.ConfigurationBeanFactoryMetaData;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.core.annotation.AnnotationAwareOrderComparator;
 import org.springframework.core.env.ConfigurableEnvironment;
 import org.springframework.core.env.StandardEnvironment;
 import org.springframework.core.io.Resource;
@@ -86,9 +84,6 @@ public class EndpointAutoConfiguration {
 	@Autowired(required = false)
 	Map<String, HealthIndicator> healthIndicators = new HashMap<String, HealthIndicator>();
 
-	@Autowired(required = false)
-	private MetricReader metricReader = new InMemoryMetricRepository();
-
 	@Autowired(required = false)
 	private Collection<PublicMetrics> publicMetrics;
 
@@ -132,11 +127,10 @@ public class EndpointAutoConfiguration {
 	@ConditionalOnMissingBean
 	public MetricsEndpoint metricsEndpoint() {
 		List<PublicMetrics> publicMetrics = new ArrayList<PublicMetrics>();
-		publicMetrics.add(new SystemPublicMetrics());
-		publicMetrics.add(new MetricReaderPublicMetrics(this.metricReader));
 		if (this.publicMetrics != null) {
 			publicMetrics.addAll(this.publicMetrics);
 		}
+		Collections.sort(publicMetrics, AnnotationAwareOrderComparator.INSTANCE);
 		return new MetricsEndpoint(publicMetrics);
 	}
 

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/MetricRepositoryAutoConfiguration.java

@@ -23,14 +23,12 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.boot.actuate.endpoint.MetricReaderPublicMetrics;
 import org.springframework.boot.actuate.endpoint.PublicMetrics;
-import org.springframework.boot.actuate.endpoint.RichGaugeReaderPublicMetrics;
 import org.springframework.boot.actuate.metrics.CounterService;
 import org.springframework.boot.actuate.metrics.GaugeService;
 import org.springframework.boot.actuate.metrics.export.Exporter;
 import org.springframework.boot.actuate.metrics.reader.MetricRegistryMetricReader;
 import org.springframework.boot.actuate.metrics.repository.InMemoryMetricRepository;
 import org.springframework.boot.actuate.metrics.repository.MetricRepository;
-import org.springframework.boot.actuate.metrics.rich.RichGaugeReader;
 import org.springframework.boot.actuate.metrics.writer.CodahaleMetricWriter;
 import org.springframework.boot.actuate.metrics.writer.CompositeMetricWriter;
 import org.springframework.boot.actuate.metrics.writer.DefaultCounterService;
@@ -39,7 +37,6 @@ import org.springframework.boot.actuate.metrics.writer.MessageChannelMetricWrite
 import org.springframework.boot.actuate.metrics.writer.MetricWriter;
 import org.springframework.boot.actuate.metrics.writer.MetricWriterMessageHandler;
 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.condition.ConditionalOnMissingClass;
@@ -124,12 +121,6 @@ public class MetricRepositoryAutoConfiguration {
 
 	}
 
-	@Bean
-	@ConditionalOnBean(RichGaugeReader.class)
-	public PublicMetrics richGaugePublicMetrics(RichGaugeReader richGaugeReader) {
-		return new RichGaugeReaderPublicMetrics(richGaugeReader);
-	}
-
 	@Configuration
 	@ConditionalOnClass(MessageChannel.class)
 	static class MetricsChannelConfiguration {
@@ -186,10 +177,11 @@ public class MetricRepositoryAutoConfiguration {
 		public MetricWriter primaryMetricWriter(List<MetricWriter> writers) {
 			return new CompositeMetricWriter(writers);
 		}
-		
+
 		@Bean
 		public PublicMetrics codahalePublicMetrics(MetricRegistry metricRegistry) {
-			MetricRegistryMetricReader reader = new MetricRegistryMetricReader(metricRegistry);
+			MetricRegistryMetricReader reader = new MetricRegistryMetricReader(
+					metricRegistry);
 			return new MetricReaderPublicMetrics(reader);
 		}
 

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/DataSourceMetricsAutoConfiguration.java → spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/PublicMetricsAutoConfiguration.java

@@ -18,31 +18,71 @@ package org.springframework.boot.actuate.autoconfigure;
 
 import javax.sql.DataSource;
 
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.actuate.endpoint.DataSourcePublicMetrics;
+import org.springframework.boot.actuate.endpoint.MetricReaderPublicMetrics;
+import org.springframework.boot.actuate.endpoint.PublicMetrics;
+import org.springframework.boot.actuate.endpoint.RichGaugeReaderPublicMetrics;
+import org.springframework.boot.actuate.endpoint.SystemPublicMetrics;
+import org.springframework.boot.actuate.metrics.reader.MetricReader;
+import org.springframework.boot.actuate.metrics.repository.InMemoryMetricRepository;
+import org.springframework.boot.actuate.metrics.rich.RichGaugeReader;
 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.jdbc.DataSourceAutoConfiguration;
 import org.springframework.boot.autoconfigure.jdbc.metadata.DataSourcePoolMetadataProvider;
 import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
 
 /**
- * {@link EnableAutoConfiguration Auto-configuration} that provides metrics on dataSource
- * usage.
+ * {@link EnableAutoConfiguration Auto-configuration} for {@link PublicMetrics}.
  *
  * @author Stephane Nicoll
+ * @author Phillip Webb
  * @since 1.2.0
  */
-@ConditionalOnBean(DataSource.class)
-@AutoConfigureAfter(DataSourceAutoConfiguration.class)
-public class DataSourceMetricsAutoConfiguration {
+@Configuration
+@AutoConfigureAfter({ DataSourceAutoConfiguration.class,
+		MetricRepositoryAutoConfiguration.class })
+@AutoConfigureBefore(EndpointAutoConfiguration.class)
+public class PublicMetricsAutoConfiguration {
+
+	@Autowired(required = false)
+	private MetricReader metricReader = new InMemoryMetricRepository();
+
+	@Bean
+	public SystemPublicMetrics systemPublicMetrics() {
+		return new SystemPublicMetrics();
+	}
 
 	@Bean
-	@ConditionalOnBean(DataSourcePoolMetadataProvider.class)
-	@ConditionalOnMissingBean
-	public DataSourcePublicMetrics dataSourcePublicMetrics() {
-		return new DataSourcePublicMetrics();
+	public MetricReaderPublicMetrics metricReaderPublicMetrics() {
+		return new MetricReaderPublicMetrics(this.metricReader);
+	}
+
+	@Bean
+	@ConditionalOnBean(RichGaugeReader.class)
+	public RichGaugeReaderPublicMetrics richGaugePublicMetrics(
+			RichGaugeReader richGaugeReader) {
+		return new RichGaugeReaderPublicMetrics(richGaugeReader);
+	}
+
+	@Configuration
+	@ConditionalOnClass(DataSource.class)
+	@ConditionalOnBean(DataSource.class)
+	static class DataSourceMetricsConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean
+		@ConditionalOnBean(DataSourcePoolMetadataProvider.class)
+		public DataSourcePublicMetrics dataSourcePublicMetrics() {
+			return new DataSourcePublicMetrics();
+		}
+
 	}
 
 }

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/DataSourcePublicMetrics.java

@@ -121,4 +121,5 @@ public class DataSourcePublicMetrics implements PublicMetrics {
 			return null;
 		}
 	}
+
 }

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

 org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
 org.springframework.boot.actuate.autoconfigure.AuditAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.CrshAutoConfiguration,\
-org.springframework.boot.actuate.autoconfigure.DataSourceMetricsAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.EndpointAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.EndpointMBeanExportAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.EndpointWebMvcAutoConfiguration,\
@@ -11,5 +10,6 @@ org.springframework.boot.actuate.autoconfigure.ManagementSecurityAutoConfigurati
 org.springframework.boot.actuate.autoconfigure.ManagementServerPropertiesAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.MetricFilterAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.MetricRepositoryAutoConfiguration,\
+org.springframework.boot.actuate.autoconfigure.PublicMetricsAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.TraceRepositoryAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.TraceWebFilterAutoConfiguration

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/autoconfigure/EndpointAutoConfigurationTests.java

@@ -103,7 +103,7 @@ public class EndpointAutoConfigurationTests {
 
 	@Test
 	public void metricEndpointsHasSystemMetricsByDefault() {
-		load(EndpointAutoConfiguration.class);
+		load(PublicMetricsAutoConfiguration.class, EndpointAutoConfiguration.class);
 		MetricsEndpoint endpoint = this.context.getBean(MetricsEndpoint.class);
 		Map<String, Object> metrics = endpoint.invoke();
 		assertTrue(metrics.containsKey("mem"));
@@ -112,7 +112,8 @@ public class EndpointAutoConfigurationTests {
 
 	@Test
 	public void metricEndpointCustomPublicMetrics() {
-		load(CustomPublicMetricsConfig.class, EndpointAutoConfiguration.class);
+		load(CustomPublicMetricsConfig.class, PublicMetricsAutoConfiguration.class,
+				EndpointAutoConfiguration.class);
 		MetricsEndpoint endpoint = this.context.getBean(MetricsEndpoint.class);
 		Map<String, Object> metrics = endpoint.invoke();
 

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/autoconfigure/MetricRepositoryAutoConfigurationTests.java

@@ -16,18 +16,13 @@
 
 package org.springframework.boot.actuate.autoconfigure;
 
-import java.util.Collection;
-import java.util.Collections;
 import java.util.concurrent.Executor;
 
 import org.junit.Test;
-import org.springframework.boot.actuate.endpoint.RichGaugeReaderPublicMetrics;
 import org.springframework.boot.actuate.metrics.CounterService;
 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.rich.RichGauge;
-import org.springframework.boot.actuate.metrics.rich.RichGaugeReader;
 import org.springframework.boot.actuate.metrics.writer.DefaultCounterService;
 import org.springframework.boot.actuate.metrics.writer.DefaultGaugeService;
 import org.springframework.boot.actuate.metrics.writer.MetricWriter;
@@ -46,8 +41,6 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertThat;
 import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
-import static org.mockito.BDDMockito.given;
 import static org.mockito.Matchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.verify;
@@ -122,44 +115,6 @@ public class MetricRepositoryAutoConfigurationTests {
 		context.close();
 	}
 
-	@Test
-	public void richGaugePublicMetrics() {
-		AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(
-				RichGaugeReaderConfig.class, MetricRepositoryAutoConfiguration.class);
-
-		RichGaugeReader richGaugeReader = context.getBean(RichGaugeReader.class);
-		assertNotNull(richGaugeReader);
-		given(richGaugeReader.findAll()).willReturn(
-				Collections.singletonList(new RichGauge("bar", 3.7d)));
-
-		RichGaugeReaderPublicMetrics publicMetrics = context
-				.getBean(RichGaugeReaderPublicMetrics.class);
-		assertNotNull(publicMetrics);
-
-		Collection<Metric<?>> metrics = publicMetrics.metrics();
-		assertNotNull(metrics);
-		assertEquals(metrics.size(), 6);
-
-		assertHasMetric(metrics, new Metric<Double>("bar.val", 3.7d));
-		assertHasMetric(metrics, new Metric<Double>("bar.avg", 3.7d));
-		assertHasMetric(metrics, new Metric<Double>("bar.min", 3.7d));
-		assertHasMetric(metrics, new Metric<Double>("bar.max", 3.7d));
-		assertHasMetric(metrics, new Metric<Double>("bar.alpha", -1.d));
-		assertHasMetric(metrics, new Metric<Long>("bar.count", 1L));
-
-		context.close();
-	}
-
-	private void assertHasMetric(Collection<Metric<?>> metrics, Metric<?> metric) {
-		for (Metric<?> m : metrics) {
-			if (m.getValue().equals(metric.getValue())
-					&& m.getName().equals(metric.getName())) {
-				return;
-			}
-		}
-		fail("Metric " + metric.toString() + " not found in " + metrics.toString());
-	}
-
 	@Configuration
 	public static class SyncTaskExecutorConfiguration {
 
@@ -195,11 +150,4 @@ public class MetricRepositoryAutoConfigurationTests {
 
 	}
 
-	@Configuration
-	static class RichGaugeReaderConfig {
-		@Bean
-		public RichGaugeReader richGaugeReader() {
-			return mock(RichGaugeReader.class);
-		}
-	}
 }

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/autoconfigure/DataSourceMetricsAutoConfigurationTests.java → spring-boot-actuator/src/test/java/org/springframework/boot/actuate/autoconfigure/PublicMetricsAutoConfigurationTests.java

@@ -19,6 +19,7 @@ package org.springframework.boot.actuate.autoconfigure;
 import java.sql.Connection;
 import java.sql.SQLException;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -28,8 +29,13 @@ import org.apache.commons.dbcp.BasicDataSource;
 import org.junit.After;
 import org.junit.Test;
 import org.springframework.boot.actuate.endpoint.DataSourcePublicMetrics;
+import org.springframework.boot.actuate.endpoint.MetricReaderPublicMetrics;
 import org.springframework.boot.actuate.endpoint.PublicMetrics;
+import org.springframework.boot.actuate.endpoint.RichGaugeReaderPublicMetrics;
+import org.springframework.boot.actuate.endpoint.SystemPublicMetrics;
 import org.springframework.boot.actuate.metrics.Metric;
+import org.springframework.boot.actuate.metrics.rich.RichGauge;
+import org.springframework.boot.actuate.metrics.rich.RichGaugeReader;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
 import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
 import org.springframework.boot.autoconfigure.jdbc.metadata.DataSourcePoolMetadataProvidersConfiguration;
@@ -44,14 +50,20 @@ import org.springframework.jdbc.core.JdbcTemplate;
 import com.zaxxer.hikari.HikariDataSource;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.Mockito.mock;
 
 /**
- * Tests for {@link DataSourceMetricsAutoConfiguration}.
+ * Tests for {@link PublicMetricsAutoConfiguration}.
  *
  * @author Stephane Nicoll
+ * @author Dave Syer
+ * @author Phillip Webb
  */
-public class DataSourceMetricsAutoConfigurationTests {
+public class PublicMetricsAutoConfigurationTests {
 
 	private AnnotationConfigApplicationContext context;
 
@@ -62,16 +74,58 @@ public class DataSourceMetricsAutoConfigurationTests {
 		}
 	}
 
+	@Test
+	public void systemPublicMetrics() throws Exception {
+		load();
+		assertEquals(1, this.context.getBeansOfType(SystemPublicMetrics.class).size());
+	}
+
+	@Test
+	public void metricReaderPublicMetrics() throws Exception {
+		load();
+		assertEquals(1, this.context.getBeansOfType(MetricReaderPublicMetrics.class)
+				.size());
+	}
+
+	@Test
+	public void richGaugePublicMetrics() {
+		AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(
+				RichGaugeReaderConfig.class, MetricRepositoryAutoConfiguration.class,
+				PublicMetricsAutoConfiguration.class);
+
+		RichGaugeReader richGaugeReader = context.getBean(RichGaugeReader.class);
+		assertNotNull(richGaugeReader);
+		given(richGaugeReader.findAll()).willReturn(
+				Collections.singletonList(new RichGauge("bar", 3.7d)));
+
+		RichGaugeReaderPublicMetrics publicMetrics = context
+				.getBean(RichGaugeReaderPublicMetrics.class);
+		assertNotNull(publicMetrics);
+
+		Collection<Metric<?>> metrics = publicMetrics.metrics();
+		assertNotNull(metrics);
+		assertEquals(metrics.size(), 6);
+
+		assertHasMetric(metrics, new Metric<Double>("bar.val", 3.7d));
+		assertHasMetric(metrics, new Metric<Double>("bar.avg", 3.7d));
+		assertHasMetric(metrics, new Metric<Double>("bar.min", 3.7d));
+		assertHasMetric(metrics, new Metric<Double>("bar.max", 3.7d));
+		assertHasMetric(metrics, new Metric<Double>("bar.alpha", -1.d));
+		assertHasMetric(metrics, new Metric<Long>("bar.count", 1L));
+
+		context.close();
+	}
+
 	@Test
 	public void noDataSource() {
 		load();
-		assertEquals(0, this.context.getBeansOfType(PublicMetrics.class).size());
+		assertEquals(0, this.context.getBeansOfType(DataSourcePublicMetrics.class).size());
 	}
 
 	@Test
 	public void autoDataSource() {
 		load(DataSourceAutoConfiguration.class);
-		PublicMetrics bean = this.context.getBean(PublicMetrics.class);
+		PublicMetrics bean = this.context.getBean(DataSourcePublicMetrics.class);
 		Collection<Metric<?>> metrics = bean.metrics();
 		assertMetrics(metrics, "datasource.primary.active", "datasource.primary.usage");
 	}
@@ -79,7 +133,7 @@ public class DataSourceMetricsAutoConfigurationTests {
 	@Test
 	public void multipleDataSources() {
 		load(MultipleDataSourcesConfig.class);
-		PublicMetrics bean = this.context.getBean(PublicMetrics.class);
+		PublicMetrics bean = this.context.getBean(DataSourcePublicMetrics.class);
 		Collection<Metric<?>> metrics = bean.metrics();
 		assertMetrics(metrics, "datasource.tomcat.active", "datasource.tomcat.usage",
 				"datasource.commonsDbcp.active", "datasource.commonsDbcp.usage");
@@ -105,7 +159,7 @@ public class DataSourceMetricsAutoConfigurationTests {
 	@Test
 	public void multipleDataSourcesWithPrimary() {
 		load(MultipleDataSourcesWithPrimaryConfig.class);
-		PublicMetrics bean = this.context.getBean(PublicMetrics.class);
+		PublicMetrics bean = this.context.getBean(DataSourcePublicMetrics.class);
 		Collection<Metric<?>> metrics = bean.metrics();
 		assertMetrics(metrics, "datasource.primary.active", "datasource.primary.usage",
 				"datasource.commonsDbcp.active", "datasource.commonsDbcp.usage");
@@ -115,11 +169,20 @@ public class DataSourceMetricsAutoConfigurationTests {
 	public void customPrefix() {
 		load(MultipleDataSourcesWithPrimaryConfig.class,
 				CustomDataSourcePublicMetrics.class);
-		PublicMetrics bean = this.context.getBean(PublicMetrics.class);
+		PublicMetrics bean = this.context.getBean(DataSourcePublicMetrics.class);
 		Collection<Metric<?>> metrics = bean.metrics();
 		assertMetrics(metrics, "ds.first.active", "ds.first.usage", "ds.second.active",
 				"ds.second.usage");
+	}
 
+	private void assertHasMetric(Collection<Metric<?>> metrics, Metric<?> metric) {
+		for (Metric<?> m : metrics) {
+			if (m.getValue().equals(metric.getValue())
+					&& m.getName().equals(metric.getName())) {
+				return;
+			}
+		}
+		fail("Metric " + metric.toString() + " not found in " + metrics.toString());
 	}
 
 	private void assertMetrics(Collection<Metric<?>> metrics, String... keys) {
@@ -138,7 +201,7 @@ public class DataSourceMetricsAutoConfigurationTests {
 			this.context.register(config);
 		}
 		this.context.register(DataSourcePoolMetadataProvidersConfiguration.class,
-				DataSourceMetricsAutoConfiguration.class);
+				PublicMetricsAutoConfiguration.class);
 		this.context.refresh();
 	}
 
@@ -198,4 +261,14 @@ public class DataSourceMetricsAutoConfigurationTests {
 				.url("jdbc:hsqldb:mem:test").username("sa");
 	}
 
+	@Configuration
+	static class RichGaugeReaderConfig {
+
+		@Bean
+		public RichGaugeReader richGaugeReader() {
+			return mock(RichGaugeReader.class);
+		}
+
+	}
+
 }