From 115ea87b14e77d5251411b1b23cf549de5543956 Mon Sep 17 00:00:00 2001
From: Andy Wilkinson <awilkinson@pivotal.io>
Date: Mon, 7 Sep 2020 10:41:10 +0100
Subject: [PATCH] Restore ordering of ErrorPageFilter lost in 49f8943

See gh-19471
---
 .../web/servlet/support/ErrorPageFilter.java  |  9 +++++---
 .../support/ErrorPageFilterConfiguration.java |  1 +
 .../SpringBootServletInitializerTests.java    | 22 +++++++++++++++++++
 3 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/support/ErrorPageFilter.java b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/support/ErrorPageFilter.java
index decd47dc3e..556959ebde 100644
--- a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/support/ErrorPageFilter.java
+++ b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/support/ErrorPageFilter.java
@@ -43,7 +43,6 @@ import org.springframework.boot.web.server.ErrorPage;
 import org.springframework.boot.web.server.ErrorPageRegistrar;
 import org.springframework.boot.web.server.ErrorPageRegistry;
 import org.springframework.core.Ordered;
-import org.springframework.core.annotation.Order;
 import org.springframework.util.ClassUtils;
 import org.springframework.web.filter.OncePerRequestFilter;
 import org.springframework.web.util.NestedServletException;
@@ -62,8 +61,7 @@ import org.springframework.web.util.NestedServletException;
  * @author Andy Wilkinson
  * @since 2.0.0
  */
-@Order(Ordered.HIGHEST_PRECEDENCE + 1)
-public class ErrorPageFilter implements Filter, ErrorPageRegistry {
+public class ErrorPageFilter implements Filter, ErrorPageRegistry, Ordered {
 
 	private static final Log logger = LogFactory.getLog(ErrorPageFilter.class);
 
@@ -298,6 +296,11 @@ public class ErrorPageFilter implements Filter, ErrorPageRegistry {
 	public void destroy() {
 	}
 
+	@Override
+	public int getOrder() {
+		return Ordered.HIGHEST_PRECEDENCE + 1;
+	}
+
 	private static void addClassIfPresent(Collection<Class<?>> collection, String className) {
 		try {
 			collection.add(ClassUtils.forName(className, null));
diff --git a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/support/ErrorPageFilterConfiguration.java b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/support/ErrorPageFilterConfiguration.java
index d019d4c295..68dd15974d 100644
--- a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/support/ErrorPageFilterConfiguration.java
+++ b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/web/servlet/support/ErrorPageFilterConfiguration.java
@@ -38,6 +38,7 @@ class ErrorPageFilterConfiguration {
 	@Bean
 	FilterRegistrationBean<ErrorPageFilter> errorPageFilterRegistration(ErrorPageFilter filter) {
 		FilterRegistrationBean<ErrorPageFilter> registration = new FilterRegistrationBean<>(filter);
+		registration.setOrder(filter.getOrder());
 		registration.setDispatcherTypes(DispatcherType.REQUEST, DispatcherType.ASYNC);
 		return registration;
 	}
diff --git a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/support/SpringBootServletInitializerTests.java b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/support/SpringBootServletInitializerTests.java
index b1bb09badc..6bada7451d 100644
--- a/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/support/SpringBootServletInitializerTests.java
+++ b/spring-boot-project/spring-boot/src/test/java/org/springframework/boot/web/servlet/support/SpringBootServletInitializerTests.java
@@ -41,6 +41,7 @@ import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.support.AbstractApplicationContext;
+import org.springframework.core.Ordered;
 import org.springframework.core.env.PropertySource;
 import org.springframework.mock.web.MockServletContext;
 import org.springframework.web.context.WebApplicationContext;
@@ -120,6 +121,27 @@ class SpringBootServletInitializerTests {
 		}
 	}
 
+	@Test
+	@SuppressWarnings("rawtypes")
+	void errorPageFilterIsRegisteredWithNearHighestPrecedence() {
+		WebServer webServer = new UndertowServletWebServerFactory(0).getWebServer((servletContext) -> {
+			try (AbstractApplicationContext context = (AbstractApplicationContext) new WithErrorPageFilter()
+					.createRootApplicationContext(servletContext)) {
+				Map<String, FilterRegistrationBean> registrations = context
+						.getBeansOfType(FilterRegistrationBean.class);
+				assertThat(registrations).hasSize(1);
+				FilterRegistrationBean errorPageFilterRegistration = registrations.get("errorPageFilterRegistration");
+				assertThat(errorPageFilterRegistration.getOrder()).isEqualTo(Ordered.HIGHEST_PRECEDENCE + 1);
+			}
+		});
+		try {
+			webServer.start();
+		}
+		finally {
+			webServer.stop();
+		}
+	}
+
 	@Test
 	@SuppressWarnings("rawtypes")
 	void errorPageFilterIsRegisteredForRequestAndAsyncDispatch() {