KAFKA-8602: Backport bugfix for standby task creation

streams/src/main/java/org/apache/kafka/streams/processor/internals/StreamThread.java

@@ -466,16 +466,18 @@ StandbyTask createTask(final Consumer<byte[], byte[]> consumer,
 
             final ProcessorTopology topology = builder.build(taskId.topicGroupId);
 
-            if (!topology.stateStores().isEmpty()) {
-                return new StandbyTask(taskId,
-                                       applicationId,
-                                       partitions,
-                                       topology,
-                                       consumer,
-                                       storeChangelogReader,
-                                       config,
-                                       streamsMetrics,
-                                       stateDirectory);
+            if (!topology.stateStores().isEmpty() && !topology.storeToChangelogTopic().isEmpty()) {
+                return new StandbyTask(
+                    taskId,
+                    applicationId,
+                    partitions,
+                    topology,
+                    consumer,
+                    storeChangelogReader,
+                    config,
+                    streamsMetrics,
+                    stateDirectory
+                );
             } else {
                 log.trace("Skipped standby task {} with assigned partitions {} " +
                     "since it does not have any state stores to materialize", taskId, partitions);

streams/src/test/java/org/apache/kafka/streams/integration/StandbyTaskCreationIntegrationTest.java

@@ -0,0 +1,189 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.apache.kafka.streams.integration;
+
+import org.apache.kafka.common.serialization.Serdes;
+import org.apache.kafka.streams.Consumed;
+import org.apache.kafka.streams.KafkaStreams;
+import org.apache.kafka.streams.KafkaStreams.State;
+import org.apache.kafka.streams.KafkaStreams.StateListener;
+import org.apache.kafka.streams.KeyValue;
+import org.apache.kafka.streams.StreamsBuilder;
+import org.apache.kafka.streams.StreamsConfig;
+import org.apache.kafka.streams.Topology;
+import org.apache.kafka.streams.integration.utils.EmbeddedKafkaCluster;
+import org.apache.kafka.streams.kstream.Transformer;
+import org.apache.kafka.streams.kstream.TransformerSupplier;
+import org.apache.kafka.streams.processor.ProcessorContext;
+import org.apache.kafka.streams.processor.ThreadMetadata;
+import org.apache.kafka.streams.state.KeyValueStore;
+import org.apache.kafka.streams.state.StoreBuilder;
+import org.apache.kafka.streams.state.Stores;
+import org.apache.kafka.test.IntegrationTest;
+import org.apache.kafka.test.TestCondition;
+import org.apache.kafka.test.TestUtils;
+import org.junit.After;
+import org.junit.BeforeClass;
+import org.junit.ClassRule;
+import org.junit.Test;
+import org.junit.experimental.categories.Category;
+
+import java.util.Properties;
+import java.util.function.Predicate;
+
+@Category({IntegrationTest.class})
+public class StandbyTaskCreationIntegrationTest {
+
+    private static final int NUM_BROKERS = 1;
+
+    @ClassRule
+    public static final EmbeddedKafkaCluster CLUSTER = new EmbeddedKafkaCluster(NUM_BROKERS);
+
+    private static final String INPUT_TOPIC = "input-topic";
+
+    private KafkaStreams client1;
+    private KafkaStreams client2;
+    private volatile boolean client1IsOk = false;
+    private volatile boolean client2IsOk = false;
+
+    @BeforeClass
+    public static void createTopics() throws InterruptedException {
+        CLUSTER.createTopic(INPUT_TOPIC, 2, 1);
+    }
+
+    @After
+    public void after() {
+        client1.close();
+        client2.close();
+    }
+
+    private Properties streamsConfiguration() {
+        final String applicationId = "testApp";
+        final Properties streamsConfiguration = new Properties();
+        streamsConfiguration.put(StreamsConfig.APPLICATION_ID_CONFIG, applicationId);
+        streamsConfiguration.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, CLUSTER.bootstrapServers());
+        streamsConfiguration.put(StreamsConfig.STATE_DIR_CONFIG, TestUtils.tempDirectory(applicationId).getPath());
+        streamsConfiguration.put(StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG, Serdes.Integer().getClass());
+        streamsConfiguration.put(StreamsConfig.DEFAULT_VALUE_SERDE_CLASS_CONFIG, Serdes.Integer().getClass());
+        streamsConfiguration.put(StreamsConfig.NUM_STANDBY_REPLICAS_CONFIG, 1);
+        return streamsConfiguration;
+    }
+
+    @Test
+    public void shouldNotCreateAnyStandByTasksForStateStoreWithLoggingDisabled() throws Exception {
+        final StreamsBuilder builder = new StreamsBuilder();
+        final String stateStoreName = "myTransformState";
+        final StoreBuilder<KeyValueStore<Integer, Integer>> keyValueStoreBuilder =
+            Stores.keyValueStoreBuilder(Stores.persistentKeyValueStore(stateStoreName),
+                                        Serdes.Integer(),
+                                        Serdes.Integer()).withLoggingDisabled();
+        builder.addStateStore(keyValueStoreBuilder);
+        builder.stream(INPUT_TOPIC, Consumed.with(Serdes.Integer(), Serdes.Integer()))
+            .transform(new TransformerSupplier<Integer, Integer, KeyValue<Integer, Integer>>() {
+                @Override
+                public Transformer<Integer, Integer, KeyValue<Integer, Integer>> get() {
+                    return new Transformer<Integer, Integer, KeyValue<Integer, Integer>>() {
+                        @SuppressWarnings("unchecked")
+                        @Override
+                        public void init(final ProcessorContext context) {}
+
+
+                        @Override
+                        public KeyValue<Integer, Integer> transform(final Integer key, final Integer value) {
+                            return null;
+                        }
+
+                        @Override
+                        public KeyValue<Integer, Integer> punctuate(final long timestamp) {
+                            return null;
+                        }
+
+                        @Override
+                        public void close() {};
+                    };
+                }
+            }, stateStoreName);
+
+        final Topology topology = builder.build();
+        createClients(topology, streamsConfiguration(), topology, streamsConfiguration());
+
+        setStateListenersForVerification(new Predicate<ThreadMetadata>() {
+            @Override
+            public boolean test(final ThreadMetadata thread) {
+                return thread.standbyTasks().isEmpty() && !thread.activeTasks().isEmpty();
+            }
+        });
+
+        startClients();
+
+        waitUntilBothClientAreOK(
+            "At least one client did not reach state RUNNING with active tasks but no stand-by tasks"
+        );
+    }
+
+    private void createClients(final Topology topology1,
+                               final Properties streamsConfiguration1,
+                               final Topology topology2,
+                               final Properties streamsConfiguration2) {
+
+        client1 = new KafkaStreams(topology1, streamsConfiguration1);
+        client2 = new KafkaStreams(topology2, streamsConfiguration2);
+    }
+
+    private void setStateListenersForVerification(final Predicate<ThreadMetadata> taskCondition) {
+        client1.setStateListener(new StateListener() {
+            @Override
+            public void onChange(final State newState, final State oldState) {
+                if (newState == State.RUNNING &&
+                    client1.localThreadsMetadata().stream().allMatch(taskCondition)) {
+
+                    client1IsOk = true;
+                }
+            }
+        });
+        client2.setStateListener(new StateListener() {
+            @Override
+            public void onChange(final State newState, final State oldState) {
+                if (newState == State.RUNNING &&
+                    client2.localThreadsMetadata().stream().allMatch(taskCondition)) {
+
+                    client2IsOk = true;
+                }
+            }
+        });
+    }
+
+    private void startClients() {
+        client1.start();
+        client2.start();
+    }
+
+    private void waitUntilBothClientAreOK(final String message) throws Exception {
+        TestUtils.waitForCondition(
+            new TestCondition() {
+                @Override
+                    public boolean conditionMet() {
+                        return client1IsOk && client2IsOk;
+                    }
+            },
+            30 * 1000,
+            message + ": "
+                + "Client 1 is " + (!client1IsOk ? "NOT " : "") + "OK, "
+                + "client 2 is " + (!client2IsOk ? "NOT " : "") + "OK."
+        );
+    }
+}

streams/src/test/java/org/apache/kafka/streams/processor/internals/StreamThreadTest.java

@@ -21,12 +21,14 @@
 import org.apache.kafka.clients.consumer.ConsumerRecord;
 import org.apache.kafka.clients.consumer.MockConsumer;
 import org.apache.kafka.clients.consumer.internals.PartitionAssignor;
+import org.apache.kafka.clients.consumer.OffsetResetStrategy;
 import org.apache.kafka.clients.producer.MockProducer;
 import org.apache.kafka.clients.producer.Producer;
 import org.apache.kafka.common.Node;
 import org.apache.kafka.common.PartitionInfo;
 import org.apache.kafka.common.TopicPartition;
 import org.apache.kafka.common.metrics.Metrics;
+import org.apache.kafka.common.utils.LogContext;
 import org.apache.kafka.common.utils.MockTime;
 import org.apache.kafka.common.utils.Utils;
 import org.apache.kafka.streams.StreamsConfig;
@@ -39,6 +41,14 @@
 import org.apache.kafka.streams.processor.ThreadMetadata;
 import org.apache.kafka.streams.processor.internals.assignment.AssignmentInfo;
 import org.apache.kafka.streams.state.HostInfo;
+import org.apache.kafka.streams.kstream.internals.MaterializedInternal;
+import org.apache.kafka.streams.processor.Processor;
+import org.apache.kafka.streams.processor.ProcessorContext;
+import org.apache.kafka.streams.processor.ProcessorSupplier;
+import org.apache.kafka.streams.state.KeyValueStore;
+import org.apache.kafka.streams.state.internals.OffsetCheckpoint;
+import org.apache.kafka.streams.processor.internals.StreamThread.StreamsMetricsThreadImpl;
+import org.apache.kafka.streams.state.StoreBuilder;
 import org.apache.kafka.streams.state.Stores;
 import org.apache.kafka.test.MockClientSupplier;
 import org.apache.kafka.test.MockProcessorSupplier;
@@ -50,6 +60,7 @@
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
+import org.slf4j.Logger;
 
 import java.lang.reflect.Field;
 import java.util.ArrayList;
@@ -67,11 +78,13 @@
 
 import static java.util.Collections.EMPTY_SET;
 import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.not;
+import static org.hamcrest.CoreMatchers.nullValue;
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertSame;
-import static org.junit.Assert.assertThat;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
@@ -1078,6 +1091,94 @@ public void shouldAlwaysUpdateTasksMetadataAfterChangingState() throws Interrupt
         assertEquals(StreamThread.State.RUNNING.name(), metadata.threadState());
     }
 
+    private static class MockProcessor implements Processor {
+        @Override
+        public void init(final ProcessorContext context) {
+
+        }
+
+        @Override
+        public void process(final Object key, final Object value) {
+
+        }
+
+        @Override
+        public void punctuate(final long timestamp) {
+
+        }
+
+        @Override
+        public void close() {
+
+        }
+    }
+
+    @Test
+    public void shouldCreateStandbyTask() {
+        setupInternalTopologyWithoutState();
+        internalTopologyBuilder.addStateStore(
+            Stores.keyValueStoreBuilder(Stores.persistentKeyValueStore("myStore"), null, null),
+            "processor1"
+        );
+
+        final StandbyTask standbyTask = createStandbyTask();
+
+        assertThat(standbyTask, not(nullValue()));
+    }
+
+    @Test
+    public void shouldNotCreateStandbyTaskWithoutStateStores() {
+        setupInternalTopologyWithoutState();
+
+        final StandbyTask standbyTask = createStandbyTask();
+
+        assertThat(standbyTask, nullValue());
+    }
+
+
+    @Test
+    public void shouldNotCreateStandbyTaskIfStateStoresHaveLoggingDisabled() {
+        setupInternalTopologyWithoutState();
+        final StoreBuilder storeBuilder =
+            Stores.keyValueStoreBuilder(Stores.persistentKeyValueStore("myStore"), null, null);
+        storeBuilder.withLoggingDisabled();
+        internalTopologyBuilder.addStateStore(storeBuilder, "processor1");
+
+        final StandbyTask standbyTask = createStandbyTask();
+
+        assertThat(standbyTask, nullValue());
+    }
+
+    private void setupInternalTopologyWithoutState() {
+        internalTopologyBuilder.addSource(null, "source1", null, null, null, "topic1");
+        internalTopologyBuilder.addProcessor("processor1", new ProcessorSupplier() {
+            @Override
+            public Processor get() {
+                return new MockProcessor();
+            }
+        }, "source1");
+    }
+
+    private StandbyTask createStandbyTask() {
+        final LogContext logContext = new LogContext("test");
+        final Logger log = logContext.logger(StreamThreadTest.class);
+        final StreamsMetricsThreadImpl streamsMetrics =
+            new StreamsMetricsThreadImpl(metrics, "", "", Collections.emptyMap());
+        final StreamThread.StandbyTaskCreator standbyTaskCreator = new StreamThread.StandbyTaskCreator(
+            internalTopologyBuilder,
+            config,
+            streamsMetrics,
+            stateDirectory,
+            streamsMetrics.taskCreatedSensor,
+            new MockChangelogReader(),
+            mockTime,
+            log);
+        return standbyTaskCreator.createTask(
+            new MockConsumer<>(OffsetResetStrategy.EARLIEST),
+            new TaskId(1, 2),
+            Collections.emptySet());
+    }
+
     @Test
     public void shouldAlwaysReturnEmptyTasksMetadataWhileRebalancingStateAndTasksNotRunning() throws InterruptedException {
         internalStreamsBuilder.stream(Collections.singleton("t1"), consumed).groupByKey().count("count-one");