Merge pull request #12022 from Tommy Ludwig

* gh-12022:
  Polish “Auto-configure FileDescriptorMetrics”
  Auto-configure FileDescriptorMetrics
  Auto-configure ClassLoaderMetrics

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/metrics/MetricsAutoConfiguration.java

@@ -18,10 +18,12 @@ package org.springframework.boot.actuate.autoconfigure.metrics;
 
 import io.micrometer.core.annotation.Timed;
 import io.micrometer.core.instrument.Clock;
+import io.micrometer.core.instrument.binder.jvm.ClassLoaderMetrics;
 import io.micrometer.core.instrument.binder.jvm.JvmGcMetrics;
 import io.micrometer.core.instrument.binder.jvm.JvmMemoryMetrics;
 import io.micrometer.core.instrument.binder.jvm.JvmThreadMetrics;
 import io.micrometer.core.instrument.binder.logging.LogbackMetrics;
+import io.micrometer.core.instrument.binder.system.FileDescriptorMetrics;
 import io.micrometer.core.instrument.binder.system.ProcessorMetrics;
 import io.micrometer.core.instrument.binder.system.UptimeMetrics;
 
@@ -92,6 +94,12 @@ public class MetricsAutoConfiguration {
 			return new JvmThreadMetrics();
 		}
 
+		@Bean
+		@ConditionalOnMissingBean
+		public ClassLoaderMetrics classLoaderMetrics() {
+			return new ClassLoaderMetrics();
+		}
+
 	}
 
 	@Configuration
@@ -119,6 +127,13 @@ public class MetricsAutoConfiguration {
 			return new ProcessorMetrics();
 		}
 
+		@Bean
+		@ConditionalOnProperty(name = "management.metrics.binders.files.enabled", matchIfMissing = true)
+		@ConditionalOnMissingBean
+		public FileDescriptorMetrics fileDescriptorMetrics() {
+			return new FileDescriptorMetrics();
+		}
+
 	}
 
 }

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

@@ -179,7 +179,13 @@
       "name": "management.info.git.mode",
       "defaultValue": "simple"
     },
-        {
+    {
+      "name": "management.metrics.binders.files.enabled",
+      "type": "java.lang.Boolean",
+      "description": "Whether to enable files metrics.",
+      "defaultValue": true
+    },
+    {
       "name": "management.metrics.binders.integration.enabled",
       "type": "java.lang.Boolean",
       "description": "Whether to enable Spring Integration metrics.",

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/metrics/MetricsAutoConfigurationTests.java

@@ -21,10 +21,12 @@ import java.util.List;
 import io.micrometer.core.instrument.Clock;
 import io.micrometer.core.instrument.MeterRegistry;
 import io.micrometer.core.instrument.binder.MeterBinder;
+import io.micrometer.core.instrument.binder.jvm.ClassLoaderMetrics;
 import io.micrometer.core.instrument.binder.jvm.JvmGcMetrics;
 import io.micrometer.core.instrument.binder.jvm.JvmMemoryMetrics;
 import io.micrometer.core.instrument.binder.jvm.JvmThreadMetrics;
 import io.micrometer.core.instrument.binder.logging.LogbackMetrics;
+import io.micrometer.core.instrument.binder.system.FileDescriptorMetrics;
 import io.micrometer.core.instrument.binder.system.ProcessorMetrics;
 import io.micrometer.core.instrument.binder.system.UptimeMetrics;
 import io.micrometer.core.instrument.composite.CompositeMeterRegistry;
@@ -94,7 +96,8 @@ public class MetricsAutoConfigurationTests {
 	public void autoConfiguresJvmMetrics() {
 		this.runner.run((context) -> assertThat(context).hasSingleBean(JvmGcMetrics.class)
 				.hasSingleBean(JvmMemoryMetrics.class)
-				.hasSingleBean(JvmThreadMetrics.class));
+				.hasSingleBean(JvmThreadMetrics.class)
+				.hasSingleBean(ClassLoaderMetrics.class));
 	}
 
 	@Test
@@ -102,7 +105,8 @@ public class MetricsAutoConfigurationTests {
 		this.runner.withPropertyValues("management.metrics.binders.jvm.enabled=false")
 				.run((context) -> assertThat(context).doesNotHaveBean(JvmGcMetrics.class)
 						.doesNotHaveBean(JvmMemoryMetrics.class)
-						.doesNotHaveBean(JvmThreadMetrics.class));
+						.doesNotHaveBean(JvmThreadMetrics.class)
+						.doesNotHaveBean(ClassLoaderMetrics.class));
 	}
 
 	@Test
@@ -111,7 +115,8 @@ public class MetricsAutoConfigurationTests {
 				.run((context) -> assertThat(context).hasSingleBean(JvmGcMetrics.class)
 						.hasBean("customJvmGcMetrics")
 						.hasSingleBean(JvmMemoryMetrics.class)
-						.hasSingleBean(JvmThreadMetrics.class));
+						.hasSingleBean(JvmThreadMetrics.class)
+						.hasSingleBean(ClassLoaderMetrics.class));
 	}
 
 	@Test
@@ -120,7 +125,8 @@ public class MetricsAutoConfigurationTests {
 				.run((context) -> assertThat(context).hasSingleBean(JvmGcMetrics.class)
 						.hasSingleBean(JvmMemoryMetrics.class)
 						.hasBean("customJvmMemoryMetrics")
-						.hasSingleBean(JvmThreadMetrics.class));
+						.hasSingleBean(JvmThreadMetrics.class)
+						.hasSingleBean(ClassLoaderMetrics.class));
 	}
 
 	@Test
@@ -129,9 +135,20 @@ public class MetricsAutoConfigurationTests {
 				.run((context) -> assertThat(context).hasSingleBean(JvmGcMetrics.class)
 						.hasSingleBean(JvmMemoryMetrics.class)
 						.hasSingleBean(JvmThreadMetrics.class)
+						.hasSingleBean(ClassLoaderMetrics.class)
 						.hasBean("customJvmThreadMetrics"));
 	}
 
+	@Test
+	public void allowsCustomClassLoaderMetricsToBeUsed() {
+		this.runner.withUserConfiguration(CustomClassLoaderMetricsConfiguration.class)
+				.run((context) -> assertThat(context).hasSingleBean(JvmGcMetrics.class)
+						.hasSingleBean(JvmMemoryMetrics.class)
+						.hasSingleBean(JvmThreadMetrics.class)
+						.hasSingleBean(ClassLoaderMetrics.class)
+						.hasBean("customClassLoaderMetrics"));
+	}
+
 	@Test
 	public void autoConfiguresLogbackMetrics() {
 		this.runner.run(
@@ -194,6 +211,27 @@ public class MetricsAutoConfigurationTests {
 						.hasBean("customProcessorMetrics"));
 	}
 
+	@Test
+	public void autoConfiguresFileDescriptorMetrics() {
+		this.runner.run((context) -> assertThat(context)
+				.hasSingleBean(FileDescriptorMetrics.class));
+	}
+
+	@Test
+	public void allowsFileDescriptorMetricsToBeDisabled() {
+		this.runner.withPropertyValues("management.metrics.binders.files.enabled=false")
+				.run((context) -> assertThat(context)
+						.doesNotHaveBean(FileDescriptorMetrics.class));
+	}
+
+	@Test
+	public void allowsCustomFileDescriptorMetricsToBeUsed() {
+		this.runner.withUserConfiguration(CustomFileDescriptorMetricsConfiguration.class)
+				.run((context) -> assertThat(context)
+						.hasSingleBean(FileDescriptorMetrics.class)
+						.hasBean("customFileDescriptorMetrics"));
+	}
+
 	@Configuration
 	static class CustomClockConfiguration {
 
@@ -256,6 +294,16 @@ public class MetricsAutoConfigurationTests {
 
 	}
 
+	@Configuration
+	static class CustomClassLoaderMetricsConfiguration {
+
+		@Bean
+		ClassLoaderMetrics customClassLoaderMetrics() {
+			return new ClassLoaderMetrics();
+		}
+
+	}
+
 	@Configuration
 	static class CustomLogbackMetricsConfiguration {
 
@@ -286,4 +334,14 @@ public class MetricsAutoConfigurationTests {
 
 	}
 
+	@Configuration
+	static class CustomFileDescriptorMetricsConfiguration {
+
+		@Bean
+		FileDescriptorMetrics customFileDescriptorMetrics() {
+			return new FileDescriptorMetrics();
+		}
+
+	}
+
 }

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

@@ -1295,6 +1295,7 @@ content into your application. Rather, pick only the properties that you need.
 	management.info.git.mode=simple # Mode to use to expose git information.
 
 	# METRICS
+	management.metrics.binders.files.enabled=true # Whether to enable files metrics.
 	management.metrics.binders.integration.enabled=true # Whether to enable Spring Integration metrics.
 	management.metrics.binders.jvm.enabled=true # Whether to enable JVM metrics.
 	management.metrics.binders.logback.enabled=true # Whether to enable Logback metrics.