Fix corePoolSize so that maximum number of messages (`maxConcurrent…

…Messages` * number of queues) are processed simultaneously. (#833)

* Fix `corePoolSize` so that maximum number of messages (`maxConcurrentMessages` * number of queues) are processed simultaneously.

* add test for maxConcurrentMessages

* fix maxMessagesPerPoll

* remove unused import

* fix parameters for a common scenario

* fix test

* fix log level

spring-cloud-aws-sqs/src/main/java/io/awspring/cloud/sqs/listener/AbstractPipelineMessageListenerContainer.java

@@ -241,7 +241,7 @@ protected TaskExecutor createTaskExecutor() {
 		ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
 		int poolSize = getContainerOptions().getMaxConcurrentMessages() * this.messageSources.size();
 		executor.setMaxPoolSize(poolSize);
-		executor.setCorePoolSize(getContainerOptions().getMaxMessagesPerPoll());
+		executor.setCorePoolSize(poolSize);
 		// Necessary due to a small racing condition between releasing the permit and releasing the thread.
 		executor.setQueueCapacity(poolSize);
 		executor.setAllowCoreThreadTimeOut(true);

spring-cloud-aws-sqs/src/test/java/io/awspring/cloud/sqs/integration/SqsIntegrationTests.java

@@ -17,6 +17,7 @@
 
 import static java.util.Collections.singletonMap;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 import io.awspring.cloud.sqs.CompletableFutures;
@@ -53,8 +54,10 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.UUID;
+import java.util.concurrent.BrokenBarrierException;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.CyclicBarrier;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.stream.Collectors;
@@ -116,6 +119,8 @@ class SqsIntegrationTests extends BaseSqsIntegrationTest {
 
 	static final String MANUALLY_CREATE_FACTORY_QUEUE_NAME = "manually_create_factory_test_queue";
 
+	static final String MAX_CONCURRENT_MESSAGES_QUEUE_NAME = "max_concurrent_messages_test_queue";
+
 	static final String LOW_RESOURCE_FACTORY = "lowResourceFactory";
 
 	static final String MANUAL_ACK_FACTORY = "manualAcknowledgementFactory";
@@ -139,7 +144,8 @@ static void beforeTests() {
 				createQueue(client, RESOLVES_PARAMETER_TYPES_QUEUE_NAME,
 						singletonMap(QueueAttributeName.VISIBILITY_TIMEOUT, "20")),
 				createQueue(client, MANUALLY_CREATE_CONTAINER_QUEUE_NAME),
-				createQueue(client, MANUALLY_CREATE_FACTORY_QUEUE_NAME)).join();
+				createQueue(client, MANUALLY_CREATE_FACTORY_QUEUE_NAME),
+				createQueue(client, MAX_CONCURRENT_MESSAGES_QUEUE_NAME)).join();
 	}
 
 	@Autowired
@@ -275,6 +281,20 @@ void manuallyCreatesFactory() throws Exception {
 		assertThat(latchContainer.manuallyCreatedFactorySinkLatch.await(10, TimeUnit.SECONDS)).isTrue();
 	}
 
+	@Test
+	void maxConcurrentMessages() {
+		List<Message<String>> messages1 = IntStream.range(0, 10)
+			.mapToObj(index -> "maxConcurrentMessages-payload-" + index)
+			.map(payload -> MessageBuilder.withPayload(payload).build()).collect(Collectors.toList());
+		List<Message<String>> messages2 = IntStream.range(10, 20)
+			.mapToObj(index -> "maxConcurrentMessages-payload-" + index)
+			.map(payload -> MessageBuilder.withPayload(payload).build()).collect(Collectors.toList());
+		sqsTemplate.sendManyAsync(MAX_CONCURRENT_MESSAGES_QUEUE_NAME, messages1);
+		sqsTemplate.sendManyAsync(MAX_CONCURRENT_MESSAGES_QUEUE_NAME, messages2);
+		logger.debug("Sent messages to queue {} with messages {} and {}", MAX_CONCURRENT_MESSAGES_QUEUE_NAME, messages1, messages2);
+		assertDoesNotThrow(() -> latchContainer.maxConcurrentMessagesBarrier.await(10, TimeUnit.SECONDS));
+	}
+
 	static class ReceivesMessageListener {
 
 		@Autowired
@@ -399,6 +419,18 @@ void listen(Message<String> message, MessageHeaders headers, Acknowledgement ack
 		}
 	}
 
+	static class MaxConcurrentMessagesListener {
+
+		@Autowired
+		LatchContainer latchContainer;
+
+		@SqsListener(queueNames = MAX_CONCURRENT_MESSAGES_QUEUE_NAME, maxMessagesPerPoll = "10", maxConcurrentMessages = "20", id = "max-concurrent-messages")
+		void listen(String message) throws BrokenBarrierException, InterruptedException {
+			logger.debug("Received message in Listener Method: " + message);
+			latchContainer.maxConcurrentMessagesBarrier.await();
+		}
+	}
+
 	static class LatchContainer {
 
 		final CountDownLatch receivesMessageLatch = new CountDownLatch(1);
@@ -421,6 +453,7 @@ static class LatchContainer {
 		final CountDownLatch acknowledgementCallbackSuccessLatch = new CountDownLatch(1);
 		final CountDownLatch acknowledgementCallbackBatchLatch = new CountDownLatch(1);
 		final CountDownLatch acknowledgementCallbackErrorLatch = new CountDownLatch(1);
+		final CyclicBarrier maxConcurrentMessagesBarrier = new CyclicBarrier(21);
 
 	}
 
@@ -612,6 +645,11 @@ ResolvesParameterTypesListener resolvesParameterTypesListener() {
 			return new ResolvesParameterTypesListener();
 		}
 
+		@Bean
+		MaxConcurrentMessagesListener maxConcurrentMessagesListener() {
+			return new MaxConcurrentMessagesListener();
+		}
+
 		@Bean
 		SqsListenerConfigurer customizer() {
 			return registrar -> {