Only start management context when parent has a web server

Fixes spring-projectsgh-38554

Author: wilkinsona

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/web/server/ChildManagementContextInitializer.java

@@ -33,6 +33,7 @@
 import org.springframework.boot.autoconfigure.context.PropertyPlaceholderAutoConfiguration;
 import org.springframework.boot.context.event.ApplicationFailedEvent;
 import org.springframework.boot.web.context.ConfigurableWebServerApplicationContext;
+import org.springframework.boot.web.context.WebServerApplicationContext;
 import org.springframework.boot.web.context.WebServerGracefulShutdownLifecycle;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextInitializer;
@@ -82,6 +83,9 @@ private ChildManagementContextInitializer(ManagementContextFactory managementCon
 
 	@Override
 	public void start() {
+		if (!(this.parentContext instanceof WebServerApplicationContext)) {
+			return;
+		}
 		if (this.managementContext == null) {
 			ConfigurableApplicationContext managementContext = createManagementContext();
 			registerBeans(managementContext);

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/web/server/ManagementContextAutoConfigurationTests.java

@@ -55,6 +55,18 @@ void childManagementContextShouldStartForEmbeddedServer(CapturedOutput output) {
 			.run((context) -> assertThat(output).satisfies(numberOfOccurrences("Tomcat started on port", 2)));
 	}
 
+	@Test
+	void childManagementContextShouldNotStartWithoutEmbeddedServer(CapturedOutput output) {
+		WebApplicationContextRunner contextRunner = new WebApplicationContextRunner()
+			.withConfiguration(AutoConfigurations.of(ManagementContextAutoConfiguration.class,
+					ServletWebServerFactoryAutoConfiguration.class, ServletManagementContextAutoConfiguration.class,
+					WebEndpointAutoConfiguration.class, EndpointAutoConfiguration.class));
+		contextRunner.withPropertyValues("server.port=0", "management.server.port=0").run((context) -> {
+			assertThat(context).hasNotFailed();
+			assertThat(output).doesNotContain("Tomcat started");
+		});
+	}
+
 	@Test
 	void childManagementContextShouldRestartWhenParentIsStoppedThenStarted(CapturedOutput output) {
 		WebApplicationContextRunner contextRunner = new WebApplicationContextRunner(