perf($RabbitMQ): set concurrent RabbitMQ listener

concurrency: 2, maxConcurrency: 2

spring-cloud-starter/src/main/java/com/jmsoftware/maf/springcloudstarter/rabbitmq/RabbitmqConfiguration.java

@@ -1,19 +1,25 @@
 package com.jmsoftware.maf.springcloudstarter.rabbitmq;
 
-import com.jmsoftware.maf.springcloudstarter.property.MafProjectProperties;
 import lombok.extern.slf4j.Slf4j;
 import lombok.val;
 import org.springframework.amqp.core.TopicExchange;
+import org.springframework.amqp.rabbit.config.SimpleRabbitListenerContainerFactory;
+import org.springframework.amqp.rabbit.connection.ConnectionFactory;
 import org.springframework.amqp.support.converter.Jackson2JsonMessageConverter;
 import org.springframework.amqp.support.converter.MessageConverter;
+import org.springframework.boot.autoconfigure.amqp.RabbitAutoConfiguration;
+import org.springframework.boot.autoconfigure.amqp.RabbitProperties;
+import org.springframework.boot.autoconfigure.amqp.SimpleRabbitListenerContainerFactoryConfigurer;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Import;
+import org.springframework.context.annotation.Primary;
 
 /**
  * Description: RabbitmqConfiguration, change description here.
  *
  * @author Johnny Miller (锺俊), email: johnnysviva@outlook.com, date: 3/9/2021 11:31 AM
+ * @see RabbitAutoConfiguration
  * @see <a href='https://spring.io/guides/gs/messaging-rabbitmq/'>Messaging with RabbitMQ</a>
  * @see
  * <a href='https://thepracticaldeveloper.com/produce-and-consume-json-messages-with-spring-boot-amqp/'>Sending and receiving JSON messages with Spring Boot AMQP and RabbitMQ</a>
@@ -22,21 +28,39 @@
 @ConditionalOnClass({TopicExchange.class})
 @Import({DelayedMessageConfiguration.class})
 public class RabbitmqConfiguration {
-    public final String topicExchangeName;
-
-    public RabbitmqConfiguration(MafProjectProperties mafProjectProperties) {
-        this.topicExchangeName = String.format("%s-topic-exchange", mafProjectProperties.getProjectParentArtifactId());
-    }
-
-    @Bean
-    TopicExchange topicExchange() {
-        val exchange = new TopicExchange(this.topicExchangeName);
-        log.info("Created topic exchange: {}", exchange);
-        return exchange;
-    }
-
     @Bean
     public MessageConverter messageConverter() {
         return new Jackson2JsonMessageConverter();
     }
+
+    /**
+     * Rabbit listener container factory.
+     *
+     * @param rabbitProperties  the rabbit properties
+     * @param configurer        the configurer
+     * @param connectionFactory the connection factory
+     * @return the simple rabbit listener container factory
+     * @see RabbitAnnotationDrivenConfiguration#directRabbitListenerContainerFactory(org.springframework.boot.autoconfigure.amqp.DirectRabbitListenerContainerFactoryConfigurer, org.springframework.amqp.rabbit.connection.ConnectionFactory)
+     */
+    @Primary
+    @Bean(name = "rabbitListenerContainerFactory")
+    public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory(
+            RabbitProperties rabbitProperties,
+            SimpleRabbitListenerContainerFactoryConfigurer configurer,
+            ConnectionFactory connectionFactory
+    ) {
+        val simpleContainer = rabbitProperties.getListener().getSimple();
+        simpleContainer.setConcurrency(2);
+        simpleContainer.setMaxConcurrency(4);
+        log.warn(
+                "Overriding `rabbitListenerContainerFactory` with custom configuration, concurrency: {}, "
+                        + "maxConcurrency: {}", simpleContainer.getConcurrency(), simpleContainer.getMaxConcurrency()
+        );
+        val factory = new SimpleRabbitListenerContainerFactory();
+        factory.setConnectionFactory(connectionFactory);
+        factory.setConcurrentConsumers(2);
+        factory.setMaxConcurrentConsumers(4);
+        configurer.configure(factory, connectionFactory);
+        return factory;
+    }
 }