diff --git a/common/queue/src/main/java/org/thingsboard/server/queue/common/AbstractTbQueueConsumerTemplate.java b/common/queue/src/main/java/org/thingsboard/server/queue/common/AbstractTbQueueConsumerTemplate.java index 07726f0254..7f12f6aab5 100644 --- a/common/queue/src/main/java/org/thingsboard/server/queue/common/AbstractTbQueueConsumerTemplate.java +++ b/common/queue/src/main/java/org/thingsboard/server/queue/common/AbstractTbQueueConsumerTemplate.java @@ -98,7 +98,10 @@ public abstract class AbstractTbQueueConsumerTemplate i doSubscribe(partitions); subscribed = true; } - records = partitions.isEmpty() ? emptyList() : doPoll(durationInMillis); + if (partitions.isEmpty()) { + return sleepAndReturnEmpty(startNanos, durationInMillis); + } + records = doPoll(durationInMillis); } finally { consumerLock.unlock(); } diff --git a/common/queue/src/test/java/org/thingsboard/server/queue/common/AbstractTbQueueConsumerTemplateTest.java b/common/queue/src/test/java/org/thingsboard/server/queue/common/AbstractTbQueueConsumerTemplateTest.java new file mode 100644 index 0000000000..a016408ad4 --- /dev/null +++ b/common/queue/src/test/java/org/thingsboard/server/queue/common/AbstractTbQueueConsumerTemplateTest.java @@ -0,0 +1,146 @@ +/** + * Copyright © 2016-2026 The Thingsboard 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 + * + * http://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.thingsboard.server.queue.common; + +import lombok.extern.slf4j.Slf4j; +import org.junit.jupiter.api.Test; +import org.junit.jupiter.api.extension.ExtendWith; +import org.mockito.junit.jupiter.MockitoExtension; +import org.thingsboard.server.common.msg.queue.TopicPartitionInfo; +import org.thingsboard.server.queue.TbQueueMsg; + +import java.util.Collections; +import java.util.List; +import java.util.Set; +import java.util.concurrent.TimeUnit; + +import static org.hamcrest.MatcherAssert.assertThat; +import static org.hamcrest.Matchers.empty; +import static org.hamcrest.Matchers.greaterThanOrEqualTo; +import static org.hamcrest.Matchers.is; +import static org.mockito.ArgumentMatchers.anyLong; +import static org.mockito.BDDMockito.never; +import static org.mockito.BDDMockito.spy; +import static org.mockito.BDDMockito.times; +import static org.mockito.BDDMockito.verify; + +@Slf4j +@ExtendWith(MockitoExtension.class) +public class AbstractTbQueueConsumerTemplateTest { + + private static final long POLL_DURATION_MS = 100L; + private static final long SLEEP_TOLERANCE_MS = 20L; + + @Test + public void givenEmptyPartitionsAndLongPollingSupported_whenPoll_thenSleepsAndDoesNotCallDoPoll() { + // Regression: with empty partitions AND isLongPollingSupported()==true (e.g. Kafka), + // poll() previously returned instantly with no sleep, causing the consumer loop to busy-spin. + TestConsumer consumer = spy(new TestConsumer("test-topic", true)); + consumer.subscribe(Collections.emptySet()); + + long startNs = System.nanoTime(); + List result = consumer.poll(POLL_DURATION_MS); + long elapsedMs = TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - startNs); + + assertThat(result, is(empty())); + verify(consumer, never()).doPoll(anyLong()); + assertThat("poll() must sleep ~durationInMillis when partitions are empty (no busy-wait)", + elapsedMs, greaterThanOrEqualTo(POLL_DURATION_MS - SLEEP_TOLERANCE_MS)); + } + + @Test + public void givenEmptyPartitionsAndNoLongPolling_whenPoll_thenSleepsAndDoesNotCallDoPoll() { + TestConsumer consumer = spy(new TestConsumer("test-topic", false)); + consumer.subscribe(Collections.emptySet()); + + long startNs = System.nanoTime(); + List result = consumer.poll(POLL_DURATION_MS); + long elapsedMs = TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - startNs); + + assertThat(result, is(empty())); + verify(consumer, never()).doPoll(anyLong()); + assertThat(elapsedMs, greaterThanOrEqualTo(POLL_DURATION_MS - SLEEP_TOLERANCE_MS)); + } + + @Test + public void givenNonEmptyPartitions_whenPoll_thenCallsDoPoll() { + TestConsumer consumer = spy(new TestConsumer("test-topic", true)); + consumer.subscribe(Collections.singleton(new TopicPartitionInfo("test-topic", null, 0, true))); + + List result = consumer.poll(POLL_DURATION_MS); + + assertThat(result, is(empty())); + verify(consumer, times(1)).doPoll(POLL_DURATION_MS); + } + + @Test + public void givenPartitionsBecomeEmptyAfterRebalance_whenPollAgain_thenStopsCallingDoPoll() { + // Reproduces the observed trigger: a rebalance leaves the consumer with an empty + // partition assignment. Subsequent poll() calls must not busy-spin or call doPoll(). + TestConsumer consumer = spy(new TestConsumer("test-topic", true)); + consumer.subscribe(Collections.singleton(new TopicPartitionInfo("test-topic", null, 0, true))); + consumer.poll(POLL_DURATION_MS); + verify(consumer, times(1)).doPoll(POLL_DURATION_MS); + + consumer.subscribe(Collections.emptySet()); + + long startNs = System.nanoTime(); + List result = consumer.poll(POLL_DURATION_MS); + long elapsedMs = TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - startNs); + + assertThat(result, is(empty())); + verify(consumer, times(1)).doPoll(anyLong()); + assertThat(elapsedMs, greaterThanOrEqualTo(POLL_DURATION_MS - SLEEP_TOLERANCE_MS)); + } + + static class TestConsumer extends AbstractTbQueueConsumerTemplate { + + private final boolean longPollingSupported; + + TestConsumer(String topic, boolean longPollingSupported) { + super(topic); + this.longPollingSupported = longPollingSupported; + } + + @Override + protected List doPoll(long durationInMillis) { + return Collections.emptyList(); + } + + @Override + protected TbQueueMsg decode(Object record) { + return null; + } + + @Override + protected void doSubscribe(Set partitions) { + } + + @Override + protected void doCommit() { + } + + @Override + protected void doUnsubscribe() { + } + + @Override + protected boolean isLongPollingSupported() { + return longPollingSupported; + } + } + +}