Merge pull request #23990 from bono007

* gh-23990:
  Polish "Auto-configure Mongo metrics"
  Auto-configure Mongo metrics

Closes gh-23990

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

@@ -0,0 +1,110 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.metrics.mongo;
+
+import com.mongodb.MongoClientSettings;
+import io.micrometer.core.instrument.MeterRegistry;
+import io.micrometer.core.instrument.binder.mongodb.DefaultMongoMetricsCommandTagsProvider;
+import io.micrometer.core.instrument.binder.mongodb.DefaultMongoMetricsConnectionPoolTagsProvider;
+import io.micrometer.core.instrument.binder.mongodb.MongoMetricsCommandListener;
+import io.micrometer.core.instrument.binder.mongodb.MongoMetricsCommandTagsProvider;
+import io.micrometer.core.instrument.binder.mongodb.MongoMetricsConnectionPoolListener;
+import io.micrometer.core.instrument.binder.mongodb.MongoMetricsConnectionPoolTagsProvider;
+
+import org.springframework.boot.actuate.autoconfigure.metrics.CompositeMeterRegistryAutoConfiguration;
+import org.springframework.boot.actuate.autoconfigure.metrics.MetricsAutoConfiguration;
+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.condition.ConditionalOnProperty;
+import org.springframework.boot.autoconfigure.mongo.MongoAutoConfiguration;
+import org.springframework.boot.autoconfigure.mongo.MongoClientSettingsBuilderCustomizer;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+/**
+ * {@link EnableAutoConfiguration Auto-configuration} for Mongo metrics.
+ *
+ * @author Chris Bono
+ * @author Jonatan Ivanov
+ * @since 2.5.0
+ */
+@Configuration(proxyBeanMethods = false)
+@AutoConfigureBefore(MongoAutoConfiguration.class)
+@AutoConfigureAfter({ MetricsAutoConfiguration.class, CompositeMeterRegistryAutoConfiguration.class })
+@ConditionalOnClass(MongoClientSettings.class)
+@ConditionalOnBean(MeterRegistry.class)
+public class MongoMetricsAutoConfiguration {
+
+	@ConditionalOnClass(MongoMetricsCommandListener.class)
+	@ConditionalOnProperty(name = "management.metrics.mongo.command.enabled", havingValue = "true",
+			matchIfMissing = true)
+	static class MongoCommandMetricsConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean
+		MongoMetricsCommandListener mongoMetricsCommandListener(MeterRegistry meterRegistry,
+				MongoMetricsCommandTagsProvider mongoMetricsCommandTagsProvider) {
+			return new MongoMetricsCommandListener(meterRegistry, mongoMetricsCommandTagsProvider);
+		}
+
+		@Bean
+		@ConditionalOnMissingBean
+		MongoMetricsCommandTagsProvider mongoMetricsCommandTagsProvider() {
+			return new DefaultMongoMetricsCommandTagsProvider();
+		}
+
+		@Bean
+		MongoClientSettingsBuilderCustomizer mongoMetricsCommandListenerClientSettingsBuilderCustomizer(
+				MongoMetricsCommandListener mongoMetricsCommandListener) {
+			return (clientSettingsBuilder) -> clientSettingsBuilder.addCommandListener(mongoMetricsCommandListener);
+		}
+
+	}
+
+	@ConditionalOnClass(MongoMetricsConnectionPoolListener.class)
+	@ConditionalOnProperty(name = "management.metrics.mongo.connectionpool.enabled", havingValue = "true",
+			matchIfMissing = true)
+	static class MongoConnectionPoolMetricsConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean
+		MongoMetricsConnectionPoolListener mongoMetricsConnectionPoolListener(MeterRegistry meterRegistry,
+				MongoMetricsConnectionPoolTagsProvider mongoMetricsConnectionPoolTagsProvider) {
+			return new MongoMetricsConnectionPoolListener(meterRegistry, mongoMetricsConnectionPoolTagsProvider);
+		}
+
+		@Bean
+		@ConditionalOnMissingBean
+		MongoMetricsConnectionPoolTagsProvider mongoMetricsConnectionPoolTagsProvider() {
+			return new DefaultMongoMetricsConnectionPoolTagsProvider();
+		}
+
+		@Bean
+		MongoClientSettingsBuilderCustomizer mongoMetricsConnectionPoolListenerClientSettingsBuilderCustomizer(
+				MongoMetricsConnectionPoolListener mongoMetricsConnectionPoolListener) {
+			return (clientSettingsBuilder) -> clientSettingsBuilder
+					.applyToConnectionPoolSettings((connectionPoolSettingsBuilder) -> connectionPoolSettingsBuilder
+							.addConnectionPoolListener(mongoMetricsConnectionPoolListener));
+		}
+
+	}
+
+}

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/metrics/mongo/package-info.java

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.
+ */
+
+/**
+ * Auto-configuration for Mongo metrics.
+ */
+package org.springframework.boot.actuate.autoconfigure.metrics.mongo;

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

@@ -521,6 +521,16 @@
         "level": "error"
       }
     },
+    {
+      "name": "management.metrics.mongo.command.enabled",
+      "description": "Whether to enable Mongo client command metrics.",
+      "defaultValue": true
+    },
+    {
+      "name": "management.metrics.mongo.connectionpool.enabled",
+      "description": "Whether to enable Mongo connection pool metrics.",
+      "defaultValue": true
+    },
     {
       "name": "management.metrics.web.client.request.autotime.enabled",
       "description": "Whether to automatically time web client requests.",

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

@@ -70,6 +70,7 @@ org.springframework.boot.actuate.autoconfigure.metrics.export.wavefront.Wavefron
 org.springframework.boot.actuate.autoconfigure.metrics.integration.IntegrationMetricsAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.metrics.jdbc.DataSourcePoolMetricsAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.metrics.jersey.JerseyServerMetricsAutoConfiguration,\
+org.springframework.boot.actuate.autoconfigure.metrics.mongo.MongoMetricsAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.metrics.orm.jpa.HibernateMetricsAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.metrics.r2dbc.ConnectionPoolMetricsAutoConfiguration,\
 org.springframework.boot.actuate.autoconfigure.metrics.web.client.HttpClientMetricsAutoConfiguration,\

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

@@ -0,0 +1,200 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.metrics.mongo;
+
+import java.util.List;
+
+import com.mongodb.MongoClientSettings;
+import com.mongodb.client.MongoClient;
+import com.mongodb.connection.ConnectionPoolSettings;
+import com.mongodb.event.ConnectionPoolListener;
+import io.micrometer.core.instrument.binder.mongodb.DefaultMongoMetricsCommandTagsProvider;
+import io.micrometer.core.instrument.binder.mongodb.DefaultMongoMetricsConnectionPoolTagsProvider;
+import io.micrometer.core.instrument.binder.mongodb.MongoMetricsCommandListener;
+import io.micrometer.core.instrument.binder.mongodb.MongoMetricsCommandTagsProvider;
+import io.micrometer.core.instrument.binder.mongodb.MongoMetricsConnectionPoolListener;
+import io.micrometer.core.instrument.binder.mongodb.MongoMetricsConnectionPoolTagsProvider;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.boot.actuate.autoconfigure.metrics.test.MetricsRun;
+import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.autoconfigure.mongo.MongoAutoConfiguration;
+import org.springframework.boot.test.context.FilteredClassLoader;
+import org.springframework.boot.test.context.assertj.AssertableApplicationContext;
+import org.springframework.boot.test.context.runner.ApplicationContextRunner;
+import org.springframework.boot.test.context.runner.ContextConsumer;
+import org.springframework.test.util.ReflectionTestUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+
+/**
+ * Tests for {@link MongoMetricsAutoConfiguration}.
+ *
+ * @author Chris Bono
+ */
+class MongoMetricsAutoConfigurationTests {
+
+	private final ApplicationContextRunner contextRunner = new ApplicationContextRunner()
+			.withConfiguration(AutoConfigurations.of(MongoMetricsAutoConfiguration.class));
+
+	@Test
+	void whenThereIsAMeterRegistryThenMetricsCommandListenerIsAdded() {
+		this.contextRunner.with(MetricsRun.simple())
+				.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class)).run((context) -> {
+					assertThat(context).hasSingleBean(MongoMetricsCommandListener.class);
+					assertThat(getActualMongoClientSettingsUsedToConstructClient(context)).isNotNull()
+							.extracting(MongoClientSettings::getCommandListeners).asList()
+							.containsExactly(context.getBean(MongoMetricsCommandListener.class));
+					assertThat(getMongoMetricsCommandTagsProviderUsedToConstructListener(context))
+							.isInstanceOf(DefaultMongoMetricsCommandTagsProvider.class);
+				});
+	}
+
+	@Test
+	void whenThereIsAMeterRegistryThenMetricsConnectionPoolListenerIsAdded() {
+		this.contextRunner.with(MetricsRun.simple())
+				.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class)).run((context) -> {
+					assertThat(context).hasSingleBean(MongoMetricsConnectionPoolListener.class);
+					assertThat(getConnectionPoolListenersFromClient(context))
+							.containsExactly(context.getBean(MongoMetricsConnectionPoolListener.class));
+					assertThat(getMongoMetricsConnectionPoolTagsProviderUsedToConstructListener(context))
+							.isInstanceOf(DefaultMongoMetricsConnectionPoolTagsProvider.class);
+				});
+	}
+
+	@Test
+	void whenThereIsNoMeterRegistryThenNoMetricsCommandListenerIsAdded() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class))
+				.run((context) -> assertThatMetricsCommandListenerNotAdded());
+	}
+
+	@Test
+	void whenThereIsNoMeterRegistryThenNoMetricsConnectionPoolListenerIsAdded() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class))
+				.run((context) -> assertThatMetricsConnectionPoolListenerNotAdded());
+	}
+
+	@Test
+	void whenThereIsACustomMetricsCommandTagsProviderItIsUsed() {
+		final MongoMetricsCommandTagsProvider customTagsProvider = mock(MongoMetricsCommandTagsProvider.class);
+		this.contextRunner.with(MetricsRun.simple())
+				.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class))
+				.withBean("customMongoMetricsCommandTagsProvider", MongoMetricsCommandTagsProvider.class,
+						() -> customTagsProvider)
+				.run((context) -> assertThat(getMongoMetricsCommandTagsProviderUsedToConstructListener(context))
+						.isSameAs(customTagsProvider));
+	}
+
+	@Test
+	void whenThereIsACustomMetricsConnectionPoolTagsProviderItIsUsed() {
+		final MongoMetricsConnectionPoolTagsProvider customTagsProvider = mock(
+				MongoMetricsConnectionPoolTagsProvider.class);
+		this.contextRunner.with(MetricsRun.simple())
+				.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class))
+				.withBean("customMongoMetricsConnectionPoolTagsProvider", MongoMetricsConnectionPoolTagsProvider.class,
+						() -> customTagsProvider)
+				.run((context) -> assertThat(getMongoMetricsConnectionPoolTagsProviderUsedToConstructListener(context))
+						.isSameAs(customTagsProvider));
+	}
+
+	@Test
+	void whenThereIsNoMongoClientSettingsOnClasspathThenNoMetricsCommandListenerIsAdded() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class))
+				.withClassLoader(new FilteredClassLoader(MongoClientSettings.class))
+				.run((context) -> assertThatMetricsCommandListenerNotAdded());
+	}
+
+	@Test
+	void whenThereIsNoMongoClientSettingsOnClasspathThenNoMetricsConnectionPoolListenerIsAdded() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class))
+				.withClassLoader(new FilteredClassLoader(MongoClientSettings.class))
+				.run((context) -> assertThatMetricsConnectionPoolListenerNotAdded());
+	}
+
+	@Test
+	void whenThereIsNoMongoMetricsCommandListenerOnClasspathThenNoMetricsCommandListenerIsAdded() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class))
+				.withClassLoader(new FilteredClassLoader(MongoMetricsCommandListener.class))
+				.run((context) -> assertThatMetricsCommandListenerNotAdded());
+	}
+
+	@Test
+	void whenThereIsNoMongoMetricsConnectionPoolListenerOnClasspathThenNoMetricsConnectionPoolListenerIsAdded() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class))
+				.withClassLoader(new FilteredClassLoader(MongoMetricsConnectionPoolListener.class))
+				.run((context) -> assertThatMetricsConnectionPoolListenerNotAdded());
+	}
+
+	@Test
+	void whenMetricsCommandListenerEnabledPropertyFalseThenNoMetricsCommandListenerIsAdded() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class))
+				.withPropertyValues("management.metrics.mongo.command.enabled:false")
+				.run((context) -> assertThatMetricsCommandListenerNotAdded());
+	}
+
+	@Test
+	void whenMetricsConnectionPoolListenerEnabledPropertyFalseThenNoMetricsConnectionPoolListenerIsAdded() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(MongoAutoConfiguration.class))
+				.withPropertyValues("management.metrics.mongo.connectionpool.enabled:false")
+				.run((context) -> assertThatMetricsConnectionPoolListenerNotAdded());
+	}
+
+	private ContextConsumer<AssertableApplicationContext> assertThatMetricsCommandListenerNotAdded() {
+		return (context) -> {
+			assertThat(context).doesNotHaveBean(MongoMetricsCommandListener.class);
+			assertThat(getActualMongoClientSettingsUsedToConstructClient(context)).isNotNull()
+					.extracting(MongoClientSettings::getCommandListeners).asList().isEmpty();
+		};
+	}
+
+	private ContextConsumer<AssertableApplicationContext> assertThatMetricsConnectionPoolListenerNotAdded() {
+		return (context) -> {
+			assertThat(context).doesNotHaveBean(MongoMetricsConnectionPoolListener.class);
+			assertThat(getConnectionPoolListenersFromClient(context)).isEmpty();
+		};
+	}
+
+	private MongoClientSettings getActualMongoClientSettingsUsedToConstructClient(
+			final AssertableApplicationContext context) {
+		final MongoClient mongoClient = context.getBean(MongoClient.class);
+		return (MongoClientSettings) ReflectionTestUtils.getField(mongoClient, "settings");
+	}
+
+	private List<ConnectionPoolListener> getConnectionPoolListenersFromClient(
+			final AssertableApplicationContext context) {
+		MongoClientSettings mongoClientSettings = getActualMongoClientSettingsUsedToConstructClient(context);
+		ConnectionPoolSettings connectionPoolSettings = mongoClientSettings.getConnectionPoolSettings();
+		@SuppressWarnings("unchecked")
+		List<ConnectionPoolListener> listeners = (List<ConnectionPoolListener>) ReflectionTestUtils
+				.getField(connectionPoolSettings, "connectionPoolListeners");
+		return listeners;
+	}
+
+	private MongoMetricsCommandTagsProvider getMongoMetricsCommandTagsProviderUsedToConstructListener(
+			final AssertableApplicationContext context) {
+		MongoMetricsCommandListener listener = context.getBean(MongoMetricsCommandListener.class);
+		return (MongoMetricsCommandTagsProvider) ReflectionTestUtils.getField(listener, "tagsProvider");
+	}
+
+	private MongoMetricsConnectionPoolTagsProvider getMongoMetricsConnectionPoolTagsProviderUsedToConstructListener(
+			final AssertableApplicationContext context) {
+		MongoMetricsConnectionPoolListener listener = context.getBean(MongoMetricsConnectionPoolListener.class);
+		return (MongoMetricsConnectionPoolTagsProvider) ReflectionTestUtils.getField(listener, "tagsProvider");
+	}
+
+}

spring-boot-project/spring-boot-docs/build.gradle

@@ -80,6 +80,7 @@ dependencies {
 	implementation("org.glassfish.jersey.core:jersey-server")
 	implementation("org.hibernate:hibernate-jcache")
 	implementation("org.jooq:jooq")
+	implementation("org.mongodb:mongodb-driver-sync")
 	implementation("org.slf4j:jul-to-slf4j")
 	implementation("org.springframework:spring-jdbc")
 	implementation("org.springframework:spring-test")

spring-boot-project/spring-boot-docs/src/docs/asciidoc/production-ready-features.adoc

@@ -2135,6 +2135,7 @@ Spring Boot registers the following core metrics when applicable:
 * Kafka consumer, producer, and streams metrics
 * Log4j2 metrics: record the number of events logged to Log4j2 at each level
 * Logback metrics: record the number of events logged to Logback at each level
+* MongoDB metrics for all commands issued from the client and for client connection pool information
 * Uptime metrics: report a gauge for uptime and a fixed gauge representing the application's absolute start time
 * Tomcat metrics (`server.tomcat.mbeanregistry.enabled` must be set to `true` for all Tomcat metrics to be registered)
 * {spring-integration-docs}system-management.html#micrometer-integration[Spring Integration] metrics
@@ -2396,6 +2397,90 @@ For more details refer to {spring-kafka-docs}#micrometer-native[Micrometer Nativ
 
 
 
+[[production-ready-metrics-mongodb]]
+==== MongoDB Metrics
+
+
+
+[[production-ready-metrics-mongodb-command]]
+===== Command Metrics
+Auto-configuration will register a `MongoMetricsCommandListener` with the auto-configured `MongoClient`.
+
+A timer metric with the name `mongodb.driver.commands` is created for each command issued to the underlying MongoDB driver.
+Each metric is tagged with the following information by default:
+|===
+| Tag | Description
+
+| `command`
+| Name of the command issued
+
+| `cluster.id`
+| Identifier of the cluster the command was sent to
+
+| `server.address`
+| Address of the server the command was sent to
+
+| `status`
+| Outcome of the command - one of (`SUCCESS`, `FAILED`)
+|===
+
+To replace the default metric tags, define a `MongoMetricsCommandTagsProvider` bean, as shown in the following example:
+
+[source,java,indent=0]
+----
+include::{include-productionreadyfeatures}/metrics/mongo/SampleCommandTagsProviderConfiguration.java[tag=*]
+----
+
+To disable the auto-configured command metrics, set the following property:
+
+[source,yaml,indent=0,configprops,configblocks]
+----
+	management:
+	  metrics:
+	    mongo:
+	      command:
+	        enabled: false
+----
+
+===== Connection Pool Metrics
+Auto-configuration will register a `MongoMetricsConnectionPoolListener` with the auto-configured `MongoClient`.
+
+The following gauge metrics are created for the connection pool:
+
+* `mongodb.driver.pool.size` that reports the current size of the connection pool, including idle and and in-use members
+* `mongodb.driver.pool.checkedout` that reports the count of connections that are currently in use
+* `mongodb.driver.pool.waitqueuesize` that reports the current size of the wait queue for a connection from the pool
+
+Each metric is tagged with the following information by default:
+|===
+| Tag | Description
+
+| `cluster.id`
+| Identifier of the cluster the connection pool corresponds to
+
+| `server.address`
+| Address of the server the connection pool corresponds to
+|===
+
+To replace the default metric tags, define a `MongoMetricsConnectionPoolTagsProvider` bean, as shown in the following example:
+
+[source,java,indent=0]
+----
+include::{include-productionreadyfeatures}/metrics/mongo/SampleConnectionPoolTagsProviderConfiguration.java[tag=*]
+----
+
+To disable the auto-configured connection pool metrics, set the following property:
+
+[source,yaml,indent=0,configprops,configblocks]
+----
+	management:
+	  metrics:
+	    mongo:
+	      connectionpool:
+	        enabled: false
+----
+
+
 [[production-ready-metrics-custom]]
 === Registering custom metrics
 To register custom metrics, inject `MeterRegistry` into your component, as shown in the following example:

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/productionreadyfeatures/metrics/mongo/SampleCommandTagsProviderConfiguration.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.productionreadyfeatures.metrics.mongo;
+
+// tag::code[]
+import com.mongodb.event.CommandEvent;
+import io.micrometer.core.instrument.Tag;
+import io.micrometer.core.instrument.binder.mongodb.MongoMetricsCommandTagsProvider;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration(proxyBeanMethods = false)
+public class SampleCommandTagsProviderConfiguration {
+
+	@Bean
+	MongoMetricsCommandTagsProvider customCommandTagsProvider() {
+		return new CustomCommandTagsProvider();
+	}
+
+}
+// end::code[]
+
+class CustomCommandTagsProvider implements MongoMetricsCommandTagsProvider {
+
+	@Override
+	public Iterable<Tag> commandTags(CommandEvent commandEvent) {
+		return java.util.Collections.emptyList();
+	}
+
+}

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/productionreadyfeatures/metrics/mongo/SampleConnectionPoolTagsProviderConfiguration.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.docs.productionreadyfeatures.metrics.mongo;
+
+// tag::code[]
+import com.mongodb.event.ConnectionPoolCreatedEvent;
+import io.micrometer.core.instrument.Tag;
+import io.micrometer.core.instrument.binder.mongodb.MongoMetricsConnectionPoolTagsProvider;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration(proxyBeanMethods = false)
+public class SampleConnectionPoolTagsProviderConfiguration {
+
+	@Bean
+	MongoMetricsConnectionPoolTagsProvider customConnectionPoolTagsProvider() {
+		return new CustomConnectionPoolTagsProvider();
+	}
+
+}
+// end::code[]
+
+class CustomConnectionPoolTagsProvider implements MongoMetricsConnectionPoolTagsProvider {
+
+	@Override
+	public Iterable<Tag> connectionPoolTags(ConnectionPoolCreatedEvent event) {
+		return java.util.Collections.emptyList();
+	}
+
+}

spring-boot-project/spring-boot-docs/src/main/java/org/springframework/boot/docs/productionreadyfeatures/metrics/mongo/package-info.java

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2012-2021 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
+ *
+ *      https://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.
+ */
+
+/**
+ * Examples for the "Production Ready Features - Metrics - MongoDB" section.
+ */
+package org.springframework.boot.docs.productionreadyfeatures.metrics.mongo;