Register task executor metrics when using lazy init

Fixes gh-37832

Author: wilkinsona

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2022 the original author or authors.
+ * Copyright 2012-2023 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.
@@ -25,6 +25,7 @@
 import io.micrometer.core.instrument.binder.jvm.ExecutorServiceMetrics;
 
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.LazyInitializationExcludeFilter;
 import org.springframework.boot.actuate.autoconfigure.metrics.MetricsAutoConfiguration;
 import org.springframework.boot.actuate.autoconfigure.metrics.export.simple.SimpleMetricsExportAutoConfiguration;
 import org.springframework.boot.autoconfigure.AutoConfiguration;
@@ -33,6 +34,7 @@
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.task.TaskExecutionAutoConfiguration;
 import org.springframework.boot.autoconfigure.task.TaskSchedulingAutoConfiguration;
+import org.springframework.context.annotation.Bean;
 import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
 import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
 
@@ -63,6 +65,11 @@ else if (executor instanceof ThreadPoolTaskScheduler) {
 		});
 	}
 
+	@Bean
+	static LazyInitializationExcludeFilter eagerTaskExecutorMetrics() {
+		return LazyInitializationExcludeFilter.forBeanTypes(TaskExecutorMetricsAutoConfiguration.class);
+	}
+
 	private void monitor(MeterRegistry registry, ThreadPoolExecutor threadPoolExecutor, String name) {
 		if (threadPoolExecutor != null) {
 			new ExecutorServiceMetrics(threadPoolExecutor, name, Collections.emptyList()).bindTo(registry);

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

@@ -24,6 +24,7 @@
 import io.micrometer.core.instrument.search.MeterNotFoundException;
 import org.junit.jupiter.api.Test;
 
+import org.springframework.boot.LazyInitializationBeanFactoryPostProcessor;
 import org.springframework.boot.actuate.autoconfigure.metrics.test.MetricsRun;
 import org.springframework.boot.autoconfigure.AutoConfigurations;
 import org.springframework.boot.autoconfigure.task.TaskExecutionAutoConfiguration;
@@ -64,6 +65,21 @@ void taskExecutorUsingAutoConfigurationIsInstrumented() {
 			});
 	}
 
+	@Test
+	void taskExecutorIsInstrumentedWhenUsingLazyInitialization() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(TaskExecutionAutoConfiguration.class))
+			.withBean(LazyInitializationBeanFactoryPostProcessor.class)
+			.run((context) -> {
+				MeterRegistry registry = context.getBean(MeterRegistry.class);
+				Collection<FunctionCounter> meters = registry.get("executor.completed").functionCounters();
+				assertThat(meters).singleElement()
+					.satisfies(
+							(meter) -> assertThat(meter.getId().getTag("name")).isEqualTo("applicationTaskExecutor"));
+				assertThatExceptionOfType(MeterNotFoundException.class)
+					.isThrownBy(() -> registry.get("executor").timer());
+			});
+	}
+
 	@Test
 	void taskExecutorsWithCustomNamesAreInstrumented() {
 		this.contextRunner.withBean("firstTaskExecutor", Executor.class, ThreadPoolTaskExecutor::new)