From fce0fef98fd766ef0f7acd821276189f8e7b1f41 Mon Sep 17 00:00:00 2001
From: Artem Bilan <abilan@vmware.com>
Date: Tue, 10 Nov 2020 12:25:30 -0500
Subject: [PATCH] GH-3425: Remove mngmt gauges from CtxClosedEvent

Fixes https://github.com/spring-projects/spring-integration/issues/3425

It turns out that `IntegrationManagementConfigurer.destroy()` is still too
late to remove `gauges` and Micrometer tries to gather them on application
context close, when many beans are already destroyed

* Catch `ContextClosedEvent` in the `IntegrationManagementConfigurer`
and removed `gauges` from there
* Remove `destroy()` impl since it is out of use already:
the `IntegrationManagementConfigurer` is not supposed to be in the
target application directly, so it looks safe to remove the `DisposableBean`
altogether

**Cherry-pick to `5.3.x` & `5.2.x`**
---
 .../config/IntegrationManagementConfigurer.java    | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/spring-integration-core/src/main/java/org/springframework/integration/config/IntegrationManagementConfigurer.java b/spring-integration-core/src/main/java/org/springframework/integration/config/IntegrationManagementConfigurer.java
index cc22e72bf4..7c1ee05e4b 100644
--- a/spring-integration-core/src/main/java/org/springframework/integration/config/IntegrationManagementConfigurer.java
+++ b/spring-integration-core/src/main/java/org/springframework/integration/config/IntegrationManagementConfigurer.java
@@ -23,11 +23,12 @@ import java.util.Set;
 
 import org.springframework.beans.BeansException;
 import org.springframework.beans.factory.BeanNameAware;
-import org.springframework.beans.factory.DisposableBean;
 import org.springframework.beans.factory.SmartInitializingSingleton;
 import org.springframework.beans.factory.config.BeanPostProcessor;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextAware;
+import org.springframework.context.ApplicationListener;
+import org.springframework.context.event.ContextClosedEvent;
 import org.springframework.integration.core.MessageSource;
 import org.springframework.integration.support.management.IntegrationManagement;
 import org.springframework.integration.support.management.IntegrationManagement.ManagementOverrides;
@@ -53,7 +54,7 @@ import org.springframework.util.Assert;
  */
 public class IntegrationManagementConfigurer
 		implements SmartInitializingSingleton, ApplicationContextAware, BeanNameAware, BeanPostProcessor,
-		DisposableBean {
+		ApplicationListener<ContextClosedEvent> {
 
 	/**
 	 * Bean name of the configurer.
@@ -169,10 +170,11 @@ public class IntegrationManagementConfigurer
 						.build());
 	}
 
-	@Override
-	public void destroy() {
-		this.gauges.forEach(MeterFacade::remove);
-		this.gauges.clear();
+	@Override public void onApplicationEvent(ContextClosedEvent event) {
+		if (event.getApplicationContext().equals(this.applicationContext)) {
+			this.gauges.forEach(MeterFacade::remove);
+			this.gauges.clear();
+		}
 	}
 
 	private static ManagementOverrides getOverrides(IntegrationManagement bean) {