Move Tomcat metrics auto-configuration into spring-boot-tomcat

spring-boot-project/spring-boot-tomcat/src/test/java/org/springframework/boot/tomcat/actuate/metrics/autoconfigure/TomcatMetricsAutoConfigurationTests.java

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+/*
+ * Copyright 2012-2025 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.tomcat.actuate.metrics.autoconfigure;
+
+import java.util.Collections;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import io.micrometer.core.instrument.MeterRegistry;
+import io.micrometer.core.instrument.binder.tomcat.TomcatMetrics;
+import io.micrometer.core.instrument.simple.SimpleMeterRegistry;
+import org.apache.tomcat.util.modeler.Registry;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.context.event.ApplicationStartedEvent;
+import org.springframework.boot.test.context.runner.ReactiveWebApplicationContextRunner;
+import org.springframework.boot.test.context.runner.WebApplicationContextRunner;
+import org.springframework.boot.tomcat.TomcatWebServer;
+import org.springframework.boot.tomcat.actuate.metrics.TomcatMetricsBinder;
+import org.springframework.boot.tomcat.autoconfigure.reactive.TomcatReactiveWebServerAutoConfiguration;
+import org.springframework.boot.tomcat.autoconfigure.servlet.TomcatServletWebServerAutoConfiguration;
+import org.springframework.boot.tomcat.reactive.TomcatReactiveWebServerFactory;
+import org.springframework.boot.tomcat.servlet.TomcatServletWebServerFactory;
+import org.springframework.boot.web.server.reactive.context.AnnotationConfigReactiveWebServerApplicationContext;
+import org.springframework.boot.web.server.servlet.context.AnnotationConfigServletWebServerApplicationContext;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.server.reactive.HttpHandler;
+import org.springframework.test.util.ReflectionTestUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+
+/**
+ * Tests for {@link TomcatMetricsAutoConfiguration}.
+ *
+ * @author Andy Wilkinson
+ */
+class TomcatMetricsAutoConfigurationTests {
+
+	@Test
+	void autoConfiguresTomcatMetricsWithEmbeddedServletTomcat() {
+		resetTomcatState();
+		new WebApplicationContextRunner(AnnotationConfigServletWebServerApplicationContext::new)
+			.withConfiguration(AutoConfigurations.of(TomcatMetricsAutoConfiguration.class,
+					TomcatServletWebServerAutoConfiguration.class))
+			.withUserConfiguration(ServletWebServerConfiguration.class, MeterRegistryConfiguration.class)
+			.withPropertyValues("server.tomcat.mbeanregistry.enabled=true")
+			.run((context) -> {
+				context.publishEvent(createApplicationStartedEvent(context.getSourceApplicationContext()));
+				assertThat(context).hasSingleBean(TomcatMetricsBinder.class);
+				SimpleMeterRegistry registry = context.getBean(SimpleMeterRegistry.class);
+				assertThat(registry.find("tomcat.sessions.active.max").meter()).isNotNull();
+				assertThat(registry.find("tomcat.threads.current").meter()).isNotNull();
+			});
+	}
+
+	@Test
+	void autoConfiguresTomcatMetricsWithEmbeddedReactiveTomcat() {
+		resetTomcatState();
+		new ReactiveWebApplicationContextRunner(AnnotationConfigReactiveWebServerApplicationContext::new)
+			.withConfiguration(AutoConfigurations.of(TomcatMetricsAutoConfiguration.class,
+					TomcatReactiveWebServerAutoConfiguration.class))
+			.withUserConfiguration(ReactiveWebServerConfiguration.class, MeterRegistryConfiguration.class)
+			.withPropertyValues("server.tomcat.mbeanregistry.enabled=true")
+			.run((context) -> {
+				context.publishEvent(createApplicationStartedEvent(context.getSourceApplicationContext()));
+				SimpleMeterRegistry registry = context.getBean(SimpleMeterRegistry.class);
+				assertThat(registry.find("tomcat.sessions.active.max").meter()).isNotNull();
+				assertThat(registry.find("tomcat.threads.current").meter()).isNotNull();
+			});
+	}
+
+	@Test
+	void autoConfiguresTomcatMetricsWithStandaloneTomcat() {
+		new WebApplicationContextRunner().withConfiguration(AutoConfigurations.of(TomcatMetricsAutoConfiguration.class))
+			.withUserConfiguration(MeterRegistryConfiguration.class)
+			.run((context) -> assertThat(context).hasSingleBean(TomcatMetricsBinder.class));
+	}
+
+	@Test
+	void allowsCustomTomcatMetricsBinderToBeUsed() {
+		new WebApplicationContextRunner().withConfiguration(AutoConfigurations.of(TomcatMetricsAutoConfiguration.class))
+			.withUserConfiguration(MeterRegistryConfiguration.class, CustomTomcatMetricsBinder.class)
+			.run((context) -> assertThat(context).hasSingleBean(TomcatMetricsBinder.class)
+				.hasBean("customTomcatMetricsBinder"));
+	}
+
+	@Test
+	void allowsCustomTomcatMetricsToBeUsed() {
+		new WebApplicationContextRunner().withConfiguration(AutoConfigurations.of(TomcatMetricsAutoConfiguration.class))
+			.withUserConfiguration(MeterRegistryConfiguration.class, CustomTomcatMetrics.class)
+			.run((context) -> assertThat(context).doesNotHaveBean(TomcatMetricsBinder.class)
+				.hasBean("customTomcatMetrics"));
+	}
+
+	private ApplicationStartedEvent createApplicationStartedEvent(ConfigurableApplicationContext context) {
+		return new ApplicationStartedEvent(new SpringApplication(), null, context, null);
+	}
+
+	private void resetTomcatState() {
+		ReflectionTestUtils.setField(Registry.class, "registry", null);
+		AtomicInteger containerCounter = (AtomicInteger) ReflectionTestUtils.getField(TomcatWebServer.class,
+				"containerCounter");
+		containerCounter.set(-1);
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	static class MeterRegistryConfiguration {
+
+		@Bean
+		SimpleMeterRegistry meterRegistry() {
+			return new SimpleMeterRegistry();
+		}
+
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	static class ServletWebServerConfiguration {
+
+		@Bean
+		TomcatServletWebServerFactory tomcatFactory() {
+			return new TomcatServletWebServerFactory(0);
+		}
+
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	static class ReactiveWebServerConfiguration {
+
+		@Bean
+		TomcatReactiveWebServerFactory tomcatFactory() {
+			return new TomcatReactiveWebServerFactory(0);
+		}
+
+		@Bean
+		HttpHandler httpHandler() {
+			return mock(HttpHandler.class);
+		}
+
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	static class CustomTomcatMetrics {
+
+		@Bean
+		TomcatMetrics customTomcatMetrics() {
+			return new TomcatMetrics(null, Collections.emptyList());
+		}
+
+	}
+
+	@Configuration(proxyBeanMethods = false)
+	static class CustomTomcatMetricsBinder {
+
+		@Bean
+		TomcatMetricsBinder customTomcatMetricsBinder(MeterRegistry meterRegistry) {
+			return new TomcatMetricsBinder(meterRegistry);
+		}
+
+	}
+
+}