Add ContainerCustomizer

- deprecate containerConfigurer `Consumer<C>` to more easily facilitate
  Boot auto configuration.

* Add docs.

Author: garyrussell

spring-rabbit/src/main/java/org/springframework/amqp/rabbit/config/AbstractRabbitListenerContainerFactory.java

@@ -119,7 +119,7 @@ public abstract class AbstractRabbitListenerContainerFactory<C extends AbstractM
 
 	private RecoveryCallback<?> recoveryCallback;
 
-	private Consumer<C> containerConfigurer;
+	private ContainerCustomizer<C> containerCustomizer;
 
 	private boolean batchListener;
 
@@ -351,9 +351,21 @@ public void setReplyRecoveryCallback(RecoveryCallback<?> recoveryCallback) {
 	 * exposed  by this container factory.
 	 * @param configurer the configurer;
 	 * @since 2.1.1
+	 * @deprecated in favor of {@link #setContainerCustomizer(ContainerCustomizer)}.
 	 */
+	@Deprecated
 	public void setContainerConfigurer(Consumer<C> configurer) {
-		this.containerConfigurer = configurer;
+		this.containerCustomizer = container -> configurer.accept(container);
+	}
+
+	/**
+	 * Set a {@link ContainerCustomizer} that is invoked after a container is created and
+	 * configured to enable further customization of the container.
+	 * @param containerCustomizer the customizer.
+	 * @since 2.2.2
+	 */
+	public void setContainerCustomizer(ContainerCustomizer<C> containerCustomizer) {
+		this.containerCustomizer = containerCustomizer;
 	}
 
 	/**
@@ -447,8 +459,8 @@ public C createListenerContainer(RabbitListenerEndpoint endpoint) {
 		}
 		initializeContainer(instance, endpoint);
 
-		if (this.containerConfigurer != null) {
-			this.containerConfigurer.accept(instance);
+		if (this.containerCustomizer != null) {
+			this.containerCustomizer.configure(instance);
 		}
 
 		return instance;

spring-rabbit/src/main/java/org/springframework/amqp/rabbit/config/ContainerCustomizer.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2019 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.amqp.rabbit.config;
+
+import org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer;
+
+/**
+ * Called by the container factory after the container is created and configured.
+ *
+ * @param <C> the container type.
+ *
+ * @author Gary Russell
+ * @since 2.2.2
+ *
+ */
+@FunctionalInterface
+public interface ContainerCustomizer<C extends AbstractMessageListenerContainer> {
+
+	/**
+	 * Configure the container.
+	 * @param container the container.
+	 */
+	void configure(C container);
+
+}

spring-rabbit/src/test/java/org/springframework/amqp/rabbit/annotation/ConsumerBatchingTests.java

@@ -183,7 +183,7 @@ public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory() {
 			factory.setBatchListener(true);
 			factory.setConsumerBatchEnabled(true);
 			factory.setBatchSize(4);
-			factory.setContainerConfigurer(
+			factory.setContainerCustomizer(
 					container -> container.setMicrometerTags(Collections.singletonMap("extraTag", "foo")));
 			return factory;
 		}

spring-rabbit/src/test/java/org/springframework/amqp/rabbit/annotation/EnableRabbitIntegrationTests.java

@@ -1554,7 +1554,7 @@ public SimpleRabbitListenerContainerFactory simpleJsonListenerContainerFactory()
 			messageConverter.getJavaTypeMapper().addTrustedPackages("*");
 			factory.setMessageConverter(messageConverter);
 			factory.setReceiveTimeout(10L);
-			factory.setContainerConfigurer(
+			factory.setContainerCustomizer(
 					container -> container.setMicrometerTags(Collections.singletonMap("extraTag", "foo")));
 			return factory;
 		}
@@ -1915,7 +1915,7 @@ public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory() {
 			factory.setConnectionFactory(rabbitConnectionFactory());
 			factory.setMessageConverter(jsonConverter());
 			factory.setReceiveTimeout(10L);
-			factory.setContainerConfigurer(container -> container.setMicrometerEnabled(false));
+			factory.setContainerCustomizer(container -> container.setMicrometerEnabled(false));
 			return factory;
 		}
 
@@ -2004,7 +2004,7 @@ public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory() {
 			factory.setConnectionFactory(rabbitConnectionFactory());
 			factory.setMessageConverter(xmlConverter());
 			factory.setReceiveTimeout(10L);
-			factory.setContainerConfigurer(container -> container.setMicrometerEnabled(false));
+			factory.setContainerCustomizer(container -> container.setMicrometerEnabled(false));
 			return factory;
 		}
 

spring-rabbit/src/test/java/org/springframework/amqp/rabbit/config/RabbitListenerContainerFactoryTests.java

@@ -103,7 +103,7 @@ public void createContainerFullConfig() {
 		this.factory.setRecoveryBackOff(recoveryBackOff);
 		this.factory.setMissingQueuesFatal(true);
 		this.factory.setAfterReceivePostProcessors(afterReceivePostProcessor);
-		this.factory.setContainerConfigurer(c -> c.setShutdownTimeout(10_000));
+		this.factory.setContainerCustomizer(c -> c.setShutdownTimeout(10_000));
 
 		assertThat(this.factory.getAdviceChain()).isEqualTo(new Advice[]{advice});
 

src/reference/asciidoc/amqp.adoc

@@ -2189,6 +2189,7 @@ public class AppConfig {
         factory.setConnectionFactory(connectionFactory());
         factory.setConcurrentConsumers(3);
         factory.setMaxConcurrentConsumers(10);
+        factory.setContainerCustomizer(container -> /* customize the container */);
         return factory;
     }
 }
@@ -2200,6 +2201,9 @@ It creates `DirectMessageListenerContainer` instances.
 
 NOTE: For information to help you choose between `SimpleRabbitListenerContainerFactory` and `DirectRabbitListenerContainerFactory`, see <<choose-container>>.
 
+Starting wih version 2.2.2, you can provide a `ContainerCustomizer` implementation (as shown above).
+This can be used to further configure the container after it has been created and configured; you can use this, for example, to set properties that are not exposed by the container factory.
+
 By default, the infrastructure looks for a bean named `rabbitListenerContainerFactory` as the source for the factory to use to create message listener containers.
 In this case, and ignoring the RabbitMQ infrastructure setup, the `processOrder` method can be invoked with a core poll size of three threads and a maximum pool size of ten threads.