Avoid duplicate customization of management web server factory

Previously, customization was performed in two places:

1. By customizers defined in the reactive and servlet web servlet
   factory auto-configuration
     - ServletWebServerFactoryAutoConfiguration
     - ReactiveWebServerFactoryAutoConfiguration
 2. By a ManagementWebServerFactoryCustomizer that delegates to
    customizers of certain types found in the application context
    hierarchy.

This led to some double customization as the customizers registered
by the auto-configuration classes were also found and called by the
ManagementWebServerFactoryCustomizer.

Additionally, the ManagementWebServerFactoryCustomizer would find
customizers from the parent context registered by
EmbeddedWebServerFactoryCustomizerAutoConfiguration.

This commit reworks the customization of the management web server
factory to remove the double customization.
ManagementWebServerFactoryCustomizer no longer delegates to
customizers that it finds in the context hierarchy. This
prevents the customizers defined in the reactive and servlet web
server factory auto-configuration classes from being called twice.
Additionally, EmbeddedWebServerFactoryCustomizerAutoConfiguration is
now registered in the child context so that its customizers continue
to be called when preparing the management context web server
factory.

Closes gh-44151

Author: wilkinsona

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/web/reactive/ReactiveManagementChildContextConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * 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.
@@ -26,15 +26,7 @@
 import org.springframework.boot.actuate.autoconfigure.web.server.ManagementWebServerFactoryCustomizer;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication.Type;
-import org.springframework.boot.autoconfigure.web.embedded.JettyVirtualThreadsWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.embedded.JettyWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.embedded.NettyWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.embedded.TomcatVirtualThreadsWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.embedded.TomcatWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.embedded.UndertowWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.reactive.ReactiveWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.reactive.TomcatReactiveWebServerFactoryCustomizer;
-import org.springframework.boot.web.reactive.server.ConfigurableReactiveWebServerFactory;
+import org.springframework.boot.web.server.ConfigurableWebServerFactory;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.http.server.reactive.ContextPathCompositeHandler;
@@ -58,9 +50,9 @@
 public class ReactiveManagementChildContextConfiguration {
 
 	@Bean
-	public ReactiveManagementWebServerFactoryCustomizer reactiveManagementWebServerFactoryCustomizer(
+	public ManagementWebServerFactoryCustomizer<ConfigurableWebServerFactory> reactiveManagementWebServerFactoryCustomizer(
 			ListableBeanFactory beanFactory) {
-		return new ReactiveManagementWebServerFactoryCustomizer(beanFactory);
+		return new ManagementWebServerFactoryCustomizer<>(beanFactory);
 	}
 
 	@Bean
@@ -73,17 +65,4 @@ public HttpHandler httpHandler(ApplicationContext applicationContext, Management
 		return httpHandler;
 	}
 
-	static class ReactiveManagementWebServerFactoryCustomizer
-			extends ManagementWebServerFactoryCustomizer<ConfigurableReactiveWebServerFactory> {
-
-		ReactiveManagementWebServerFactoryCustomizer(ListableBeanFactory beanFactory) {
-			super(beanFactory, ReactiveWebServerFactoryCustomizer.class, TomcatWebServerFactoryCustomizer.class,
-					TomcatReactiveWebServerFactoryCustomizer.class,
-					TomcatVirtualThreadsWebServerFactoryCustomizer.class, JettyWebServerFactoryCustomizer.class,
-					JettyVirtualThreadsWebServerFactoryCustomizer.class, UndertowWebServerFactoryCustomizer.class,
-					NettyWebServerFactoryCustomizer.class);
-		}
-
-	}
-
 }

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/web/reactive/ReactiveManagementContextAutoConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2022 the original author or authors.
+ * 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.
@@ -25,6 +25,7 @@
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication.Type;
+import org.springframework.boot.autoconfigure.web.embedded.EmbeddedWebServerFactoryCustomizerAutoConfiguration;
 import org.springframework.boot.autoconfigure.web.reactive.ReactiveWebServerFactoryAutoConfiguration;
 import org.springframework.boot.web.reactive.server.ReactiveWebServerFactory;
 import org.springframework.context.annotation.Bean;
@@ -44,7 +45,8 @@ public class ReactiveManagementContextAutoConfiguration {
 	@Bean
 	public static ManagementContextFactory reactiveWebChildContextFactory() {
 		return new ManagementContextFactory(WebApplicationType.REACTIVE, ReactiveWebServerFactory.class,
-				ReactiveWebServerFactoryAutoConfiguration.class);
+				ReactiveWebServerFactoryAutoConfiguration.class,
+				EmbeddedWebServerFactoryCustomizerAutoConfiguration.class);
 	}
 
 }

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2024 the original author or authors.
+ * 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.
@@ -39,7 +39,7 @@
  * @author Andy Wilkinson
  * @since 2.0.0
  */
-public abstract class ManagementWebServerFactoryCustomizer<T extends ConfigurableWebServerFactory>
+public class ManagementWebServerFactoryCustomizer<T extends ConfigurableWebServerFactory>
 		implements WebServerFactoryCustomizer<T>, Ordered {
 
 	private final ListableBeanFactory beanFactory;
@@ -48,12 +48,24 @@ public abstract class ManagementWebServerFactoryCustomizer<T extends Configurabl
 
 	@SafeVarargs
 	@SuppressWarnings("varargs")
+	@Deprecated(since = "3.5.0", forRemoval = true)
 	protected ManagementWebServerFactoryCustomizer(ListableBeanFactory beanFactory,
 			Class<? extends WebServerFactoryCustomizer<?>>... customizerClasses) {
 		this.beanFactory = beanFactory;
 		this.customizerClasses = customizerClasses;
 	}
 
+	/**
+	 * Creates a new customizer that will retrieve beans using the given
+	 * {@code beanFactory}.
+	 * @param beanFactory the bean factory to use
+	 * @since 3.5.0
+	 */
+	public ManagementWebServerFactoryCustomizer(ListableBeanFactory beanFactory) {
+		this.beanFactory = beanFactory;
+		this.customizerClasses = null;
+	}
+
 	@Override
 	public int getOrder() {
 		return 0;
@@ -65,7 +77,9 @@ public final void customize(T factory) {
 			.beanOfTypeIncludingAncestors(this.beanFactory, ManagementServerProperties.class);
 		// Customize as per the parent context first (so e.g. the access logs go to
 		// the same place)
-		customizeSameAsParentContext(factory);
+		if (this.customizerClasses != null) {
+			customizeSameAsParentContext(factory);
+		}
 		// Then reset the error pages
 		factory.setErrorPages(Collections.emptySet());
 		// and add the management-specific bits

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/web/servlet/ServletManagementChildContextConfiguration.java

@@ -39,14 +39,6 @@
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication.Type;
 import org.springframework.boot.autoconfigure.condition.SearchStrategy;
 import org.springframework.boot.autoconfigure.web.ServerProperties;
-import org.springframework.boot.autoconfigure.web.embedded.JettyVirtualThreadsWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.embedded.JettyWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.embedded.TomcatVirtualThreadsWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.embedded.TomcatWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.embedded.UndertowWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.servlet.ServletWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.servlet.TomcatServletWebServerFactoryCustomizer;
-import org.springframework.boot.autoconfigure.web.servlet.UndertowServletWebServerFactoryCustomizer;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
 import org.springframework.boot.web.embedded.jetty.JettyServletWebServerFactory;
 import org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory;
@@ -125,10 +117,7 @@ static class ServletManagementWebServerFactoryCustomizer
 			extends ManagementWebServerFactoryCustomizer<ConfigurableServletWebServerFactory> {
 
 		ServletManagementWebServerFactoryCustomizer(ListableBeanFactory beanFactory) {
-			super(beanFactory, ServletWebServerFactoryCustomizer.class, TomcatServletWebServerFactoryCustomizer.class,
-					TomcatWebServerFactoryCustomizer.class, TomcatVirtualThreadsWebServerFactoryCustomizer.class,
-					JettyWebServerFactoryCustomizer.class, JettyVirtualThreadsWebServerFactoryCustomizer.class,
-					UndertowServletWebServerFactoryCustomizer.class, UndertowWebServerFactoryCustomizer.class);
+			super(beanFactory);
 		}
 
 		@Override

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/web/servlet/ServletManagementContextAutoConfiguration.java

@@ -27,6 +27,7 @@
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication.Type;
+import org.springframework.boot.autoconfigure.web.embedded.EmbeddedWebServerFactoryCustomizerAutoConfiguration;
 import org.springframework.boot.autoconfigure.web.servlet.ServletWebServerFactoryAutoConfiguration;
 import org.springframework.boot.web.servlet.filter.ApplicationContextHeaderFilter;
 import org.springframework.boot.web.servlet.server.ServletWebServerFactory;
@@ -49,7 +50,8 @@ public class ServletManagementContextAutoConfiguration {
 	@Bean
 	public static ManagementContextFactory servletWebChildContextFactory() {
 		return new ManagementContextFactory(WebApplicationType.SERVLET, ServletWebServerFactory.class,
-				ServletWebServerFactoryAutoConfiguration.class);
+				ServletWebServerFactoryAutoConfiguration.class,
+				EmbeddedWebServerFactoryCustomizerAutoConfiguration.class);
 	}
 
 	@Bean