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/*
 * 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;

import org.apache.kafka.clients.CommonClientConfigs;
import org.apache.kafka.clients.admin.Admin;
import org.apache.kafka.clients.admin.ListOffsetsResult.ListOffsetsResultInfo;
import org.apache.kafka.clients.admin.MemberToRemove;
import org.apache.kafka.clients.admin.RemoveMembersFromConsumerGroupOptions;
import org.apache.kafka.clients.admin.RemoveMembersFromConsumerGroupResult;
import org.apache.kafka.clients.consumer.KafkaConsumer;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.common.KafkaFuture;
import org.apache.kafka.common.Metric;
import org.apache.kafka.common.MetricName;
import org.apache.kafka.common.TopicPartition;
import org.apache.kafka.common.Uuid;
import org.apache.kafka.common.annotation.InterfaceStability.Evolving;
import org.apache.kafka.common.errors.TimeoutException;
import org.apache.kafka.common.metrics.KafkaMetricsContext;
import org.apache.kafka.common.metrics.MetricConfig;
import org.apache.kafka.common.metrics.Metrics;
import org.apache.kafka.common.metrics.MetricsContext;
import org.apache.kafka.common.metrics.MetricsReporter;
import org.apache.kafka.common.metrics.Sensor;
import org.apache.kafka.common.metrics.Sensor.RecordingLevel;
import org.apache.kafka.common.serialization.Serializer;
import org.apache.kafka.common.utils.LogContext;
import org.apache.kafka.common.utils.Time;
import org.apache.kafka.common.utils.Timer;
import org.apache.kafka.streams.errors.InvalidStateStoreException;
import org.apache.kafka.streams.errors.InvalidStateStorePartitionException;
import org.apache.kafka.streams.errors.ProcessorStateException;
import org.apache.kafka.streams.errors.StreamsException;
import org.apache.kafka.streams.errors.StreamsNotStartedException;
import org.apache.kafka.streams.errors.StreamsStoppedException;
import org.apache.kafka.streams.errors.StreamsUncaughtExceptionHandler;
import org.apache.kafka.streams.errors.UnknownStateStoreException;
import org.apache.kafka.streams.internals.ClientInstanceIdsImpl;
import org.apache.kafka.streams.internals.metrics.ClientMetrics;
import org.apache.kafka.streams.processor.StandbyUpdateListener;
import org.apache.kafka.streams.processor.StateRestoreListener;
import org.apache.kafka.streams.processor.StateStore;
import org.apache.kafka.streams.processor.StreamPartitioner;
import org.apache.kafka.streams.processor.TaskId;
import org.apache.kafka.streams.processor.internals.ClientUtils;
import org.apache.kafka.streams.processor.internals.GlobalStreamThread;
import org.apache.kafka.streams.processor.internals.StateDirectory;
import org.apache.kafka.streams.processor.internals.StreamThread;
import org.apache.kafka.streams.processor.internals.StreamsMetadataState;
import org.apache.kafka.streams.processor.internals.Task;
import org.apache.kafka.streams.processor.internals.ThreadStateTransitionValidator;
import org.apache.kafka.streams.processor.internals.TopologyMetadata;
import org.apache.kafka.streams.processor.internals.assignment.AssignorError;
import org.apache.kafka.streams.processor.internals.metrics.StreamsMetricsImpl;
import org.apache.kafka.streams.processor.internals.namedtopology.NamedTopology;
import org.apache.kafka.streams.query.FailureReason;
import org.apache.kafka.streams.query.PositionBound;
import org.apache.kafka.streams.query.QueryConfig;
import org.apache.kafka.streams.query.QueryResult;
import org.apache.kafka.streams.query.StateQueryRequest;
import org.apache.kafka.streams.query.StateQueryResult;
import org.apache.kafka.streams.state.HostInfo;
import org.apache.kafka.streams.state.internals.GlobalStateStoreProvider;
import org.apache.kafka.streams.state.internals.QueryableStoreProvider;
import org.apache.kafka.streams.state.internals.StreamThreadStateStoreProvider;
import org.slf4j.Logger;

import java.time.Duration;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;
import java.util.Properties;
import java.util.Set;
import java.util.TreeMap;
import java.util.UUID;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.BiConsumer;
import java.util.function.Consumer;
import java.util.function.Supplier;
import java.util.stream.Collectors;

import static org.apache.kafka.streams.errors.StreamsUncaughtExceptionHandler.StreamThreadExceptionResponse.SHUTDOWN_CLIENT;
import static org.apache.kafka.streams.internals.ApiUtils.prepareMillisCheckFailMsgPrefix;
import static org.apache.kafka.streams.internals.ApiUtils.validateMillisecondDuration;
import static org.apache.kafka.streams.internals.StreamsConfigUtils.getTotalCacheSize;
import static org.apache.kafka.streams.processor.internals.ClientUtils.fetchEndOffsets;
import static org.apache.kafka.streams.processor.internals.TopologyMetadata.UNNAMED_TOPOLOGY;

/**
 * A Kafka client that allows for performing continuous computation on input coming from one or more input topics and
 * sends output to zero, one, or more output topics.
 * 

* The computational logic can be specified either by using the {@link Topology} to define a DAG topology of * {@link org.apache.kafka.streams.processor.api.Processor}s or by using the {@link StreamsBuilder} which provides the high-level DSL to define * transformations. *

* One {@code KafkaStreams} instance can contain one or more threads specified in the configs for the processing work. *

* A {@code KafkaStreams} instance can co-ordinate with any other instances with the same * {@link StreamsConfig#APPLICATION_ID_CONFIG application ID} (whether in the same process, on other processes on this * machine, or on remote machines) as a single (possibly distributed) stream processing application. * These instances will divide up the work based on the assignment of the input topic partitions so that all partitions * are being consumed. * If instances are added or fail, all (remaining) instances will rebalance the partition assignment among themselves * to balance processing load and ensure that all input topic partitions are processed. *

* Internally a {@code KafkaStreams} instance contains a normal {@link KafkaProducer} and {@link KafkaConsumer} instance * that is used for reading input and writing output. *

* A simple example might look like this: *

{@code
 * Properties props = new Properties();
 * props.put(StreamsConfig.APPLICATION_ID_CONFIG, "my-stream-processing-application");
 * props.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
 * props.put(StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG, Serdes.String().getClass());
 * props.put(StreamsConfig.DEFAULT_VALUE_SERDE_CLASS_CONFIG, Serdes.String().getClass());
 *
 * StreamsBuilder builder = new StreamsBuilder();
 * builder.stream("my-input-topic").mapValues(value -> String.valueOf(value.length())).to("my-output-topic");
 *
 * KafkaStreams streams = new KafkaStreams(builder.build(), props);
 * streams.start();
 * }
* * @see org.apache.kafka.streams.StreamsBuilder * @see org.apache.kafka.streams.Topology */ public class KafkaStreams implements AutoCloseable { private static final String JMX_PREFIX = "kafka.streams"; // processId is expected to be unique across JVMs and to be used // in userData of the subscription request to allow assignor be aware // of the co-location of stream thread's consumers. It is for internal // usage only and should not be exposed to users at all. private final Time time; private final Logger log; protected final String clientId; private final Metrics metrics; protected final StreamsConfig applicationConfigs; protected final List threads; protected final StateDirectory stateDirectory; protected final StreamsMetadataState streamsMetadataState; private final ScheduledExecutorService stateDirCleaner; private final ScheduledExecutorService rocksDBMetricsRecordingService; protected final Admin adminClient; private final StreamsMetricsImpl streamsMetrics; private final long totalCacheSize; private final StreamStateListener streamStateListener; private final DelegatingStateRestoreListener delegatingStateRestoreListener; private final Map threadState; private final UUID processId; private final KafkaClientSupplier clientSupplier; protected final TopologyMetadata topologyMetadata; private final QueryableStoreProvider queryableStoreProvider; private final DelegatingStandbyUpdateListener delegatingStandbyUpdateListener; GlobalStreamThread globalStreamThread; private KafkaStreams.StateListener stateListener; private boolean oldHandler; private BiConsumer streamsUncaughtExceptionHandler; private final Object changeThreadCount = new Object(); // container states /** * Kafka Streams states are the possible state that a Kafka Streams instance can be in. * An instance must only be in one state at a time. * The expected state transition with the following defined states is: * *
     *                 +--------------+
     *         +<----- | Created (0)  |
     *         |       +-----+--------+
     *         |             |
     *         |             v
     *         |       +----+--+------+
     *         |       | Re-          |
     *         +<----- | Balancing (1)| -------->+
     *         |       +-----+-+------+          |
     *         |             | ^                 |
     *         |             v |                 |
     *         |       +--------------+          v
     *         |       | Running (2)  | -------->+
     *         |       +------+-------+          |
     *         |              |                  |
     *         |              v                  |
     *         |       +------+-------+     +----+-------+
     *         +-----> | Pending      |     | Pending    |
     *                 | Shutdown (3) |     | Error (5)  |
     *                 +------+-------+     +-----+------+
     *                        |                   |
     *                        v                   v
     *                 +------+-------+     +-----+--------+
     *                 | Not          |     | Error (6)    |
     *                 | Running (4)  |     +--------------+
     *                 +--------------+
     *
     *
     * 
* Note the following: * - RUNNING state will transit to REBALANCING if any of its threads is in PARTITION_REVOKED or PARTITIONS_ASSIGNED state * - REBALANCING state will transit to RUNNING if all of its threads are in RUNNING state * - Any state except NOT_RUNNING, PENDING_ERROR or ERROR can go to PENDING_SHUTDOWN (whenever close is called) * - Of special importance: If the global stream thread dies, or all stream threads die (or both) then * the instance will be in the ERROR state. The user will not need to close it. */ public enum State { // Note: if you add a new state, check the below methods and how they are used within Streams to see if // any of them should be updated to include the new state. For example a new shutdown path or terminal // state would likely need to be included in methods like isShuttingDown(), hasCompletedShutdown(), etc. CREATED(1, 3), // 0 REBALANCING(2, 3, 5), // 1 RUNNING(1, 2, 3, 5), // 2 PENDING_SHUTDOWN(4), // 3 NOT_RUNNING, // 4 PENDING_ERROR(6), // 5 ERROR; // 6 private final Set validTransitions = new HashSet<>(); State(final Integer... validTransitions) { this.validTransitions.addAll(Arrays.asList(validTransitions)); } public boolean hasNotStarted() { return equals(CREATED); } public boolean isRunningOrRebalancing() { return equals(RUNNING) || equals(REBALANCING); } public boolean isShuttingDown() { return equals(PENDING_SHUTDOWN) || equals(PENDING_ERROR); } public boolean hasCompletedShutdown() { return equals(NOT_RUNNING) || equals(ERROR); } public boolean hasStartedOrFinishedShuttingDown() { return isShuttingDown() || hasCompletedShutdown(); } public boolean isValidTransition(final State newState) { return validTransitions.contains(newState.ordinal()); } } private final Object stateLock = new Object(); protected volatile State state = State.CREATED; private boolean waitOnState(final State targetState, final long waitMs) { final long begin = time.milliseconds(); synchronized (stateLock) { boolean interrupted = false; long elapsedMs = 0L; try { while (state != targetState) { if (waitMs > elapsedMs) { final long remainingMs = waitMs - elapsedMs; try { stateLock.wait(remainingMs); } catch (final InterruptedException e) { interrupted = true; } } else { log.debug("Cannot transit to {} within {}ms", targetState, waitMs); return false; } elapsedMs = time.milliseconds() - begin; } } finally { // Make sure to restore the interruption status before returning. // We do not always own the current thread that executes this method, i.e., we do not know the // interruption policy of the thread. The least we can do is restore the interruption status before // the current thread exits this method. if (interrupted) { Thread.currentThread().interrupt(); } } return true; } } /** * Sets the state * @param newState New state */ private boolean setState(final State newState) { final State oldState; synchronized (stateLock) { oldState = state; if (state == State.PENDING_SHUTDOWN && newState != State.NOT_RUNNING) { // when the state is already in PENDING_SHUTDOWN, all other transitions than NOT_RUNNING (due to thread dying) will be // refused but we do not throw exception here, to allow appropriate error handling return false; } else if (state == State.NOT_RUNNING && (newState == State.PENDING_SHUTDOWN || newState == State.NOT_RUNNING)) { // when the state is already in NOT_RUNNING, its transition to PENDING_SHUTDOWN or NOT_RUNNING (due to consecutive close calls) // will be refused but we do not throw exception here, to allow idempotent close calls return false; } else if (state == State.REBALANCING && newState == State.REBALANCING) { // when the state is already in REBALANCING, it should not transit to REBALANCING again return false; } else if (state == State.ERROR && (newState == State.PENDING_ERROR || newState == State.ERROR)) { // when the state is already in ERROR, its transition to PENDING_ERROR or ERROR (due to consecutive close calls) return false; } else if (state == State.PENDING_ERROR && newState != State.ERROR) { // when the state is already in PENDING_ERROR, all other transitions than ERROR (due to thread dying) will be // refused but we do not throw exception here, to allow appropriate error handling return false; } else if (!state.isValidTransition(newState)) { throw new IllegalStateException("Stream-client " + clientId + ": Unexpected state transition from " + oldState + " to " + newState); } else { log.info("State transition from {} to {}", oldState, newState); } state = newState; stateLock.notifyAll(); } // we need to call the user customized state listener outside the state lock to avoid potential deadlocks if (stateListener != null) { stateListener.onChange(newState, oldState); } return true; } /** * Return the current {@link State} of this {@code KafkaStreams} instance. * * @return the current state of this Kafka Streams instance */ public State state() { return state; } protected boolean isRunningOrRebalancing() { synchronized (stateLock) { return state.isRunningOrRebalancing(); } } protected boolean hasStartedOrFinishedShuttingDown() { synchronized (stateLock) { return state.hasStartedOrFinishedShuttingDown(); } } protected void validateIsRunningOrRebalancing() { synchronized (stateLock) { if (state.hasNotStarted()) { throw new StreamsNotStartedException("KafkaStreams has not been started, you can retry after calling start()"); } if (!state.isRunningOrRebalancing()) { throw new IllegalStateException("KafkaStreams is not running. State is " + state + "."); } } } /** * Listen to {@link State} change events. */ public interface StateListener { /** * Called when state changes. * * @param newState new state * @param oldState previous state */ void onChange(final State newState, final State oldState); } /** * An app can set a single {@link KafkaStreams.StateListener} so that the app is notified when state changes. * * @param listener a new state listener * @throws IllegalStateException if this {@code KafkaStreams} instance has already been started. */ public void setStateListener(final KafkaStreams.StateListener listener) { synchronized (stateLock) { if (state.hasNotStarted()) { stateListener = listener; } else { throw new IllegalStateException("Can only set StateListener before calling start(). Current state is: " + state); } } } /** * Set the handler invoked when an internal {@link StreamsConfig#NUM_STREAM_THREADS_CONFIG stream thread} abruptly * terminates due to an uncaught exception. * * @param uncaughtExceptionHandler the uncaught exception handler for all internal threads; {@code null} deletes the current handler * @throws IllegalStateException if this {@code KafkaStreams} instance has already been started. * * @deprecated Since 2.8.0. Use {@link KafkaStreams#setUncaughtExceptionHandler(StreamsUncaughtExceptionHandler)} instead. * */ @Deprecated public void setUncaughtExceptionHandler(final Thread.UncaughtExceptionHandler uncaughtExceptionHandler) { synchronized (stateLock) { if (state.hasNotStarted()) { oldHandler = true; processStreamThread(thread -> thread.setUncaughtExceptionHandler(uncaughtExceptionHandler)); if (globalStreamThread != null) { globalStreamThread.setUncaughtExceptionHandler(uncaughtExceptionHandler); } } else { throw new IllegalStateException("Can only set UncaughtExceptionHandler before calling start(). " + "Current state is: " + state); } } } /** * Set the handler invoked when an internal {@link StreamsConfig#NUM_STREAM_THREADS_CONFIG stream thread} * throws an unexpected exception. * These might be exceptions indicating rare bugs in Kafka Streams, or they * might be exceptions thrown by your code, for example a NullPointerException thrown from your processor logic. * The handler will execute on the thread that produced the exception. * In order to get the thread that threw the exception, use {@code Thread.currentThread()}. *

* Note, this handler must be threadsafe, since it will be shared among all threads, and invoked from any * thread that encounters such an exception. * * @param userStreamsUncaughtExceptionHandler the uncaught exception handler of type {@link StreamsUncaughtExceptionHandler} for all internal threads * @throws IllegalStateException if this {@code KafkaStreams} instance has already been started. * @throws NullPointerException if userStreamsUncaughtExceptionHandler is null. */ public void setUncaughtExceptionHandler(final StreamsUncaughtExceptionHandler userStreamsUncaughtExceptionHandler) { synchronized (stateLock) { if (state.hasNotStarted()) { Objects.requireNonNull(userStreamsUncaughtExceptionHandler); streamsUncaughtExceptionHandler = (exception, skipThreadReplacement) -> handleStreamsUncaughtException(exception, userStreamsUncaughtExceptionHandler, skipThreadReplacement); processStreamThread(thread -> thread.setStreamsUncaughtExceptionHandler(streamsUncaughtExceptionHandler)); if (globalStreamThread != null) { globalStreamThread.setUncaughtExceptionHandler( exception -> handleStreamsUncaughtException(exception, userStreamsUncaughtExceptionHandler, false) ); } processStreamThread(thread -> thread.setUncaughtExceptionHandler((t, e) -> { } )); if (globalStreamThread != null) { globalStreamThread.setUncaughtExceptionHandler((t, e) -> { } ); } } else { throw new IllegalStateException("Can only set UncaughtExceptionHandler before calling start(). " + "Current state is: " + state); } } } private void defaultStreamsUncaughtExceptionHandler(final Throwable throwable, final boolean skipThreadReplacement) { if (oldHandler) { threads.remove(Thread.currentThread()); if (throwable instanceof RuntimeException) { throw (RuntimeException) throwable; } else if (throwable instanceof Error) { throw (Error) throwable; } else { throw new RuntimeException("Unexpected checked exception caught in the uncaught exception handler", throwable); } } else { handleStreamsUncaughtException(throwable, t -> SHUTDOWN_CLIENT, skipThreadReplacement); } } private void replaceStreamThread(final Throwable throwable) { if (globalStreamThread != null && Thread.currentThread().getName().equals(globalStreamThread.getName())) { log.warn("The global thread cannot be replaced. Reverting to shutting down the client."); log.error("Encountered the following exception during processing " + " The streams client is going to shut down now. ", throwable); closeToError(); } final StreamThread deadThread = (StreamThread) Thread.currentThread(); deadThread.shutdown(); addStreamThread(); if (throwable instanceof RuntimeException) { throw (RuntimeException) throwable; } else if (throwable instanceof Error) { throw (Error) throwable; } else { throw new RuntimeException("Unexpected checked exception caught in the uncaught exception handler", throwable); } } private void handleStreamsUncaughtException(final Throwable throwable, final StreamsUncaughtExceptionHandler streamsUncaughtExceptionHandler, final boolean skipThreadReplacement) { final StreamsUncaughtExceptionHandler.StreamThreadExceptionResponse action = streamsUncaughtExceptionHandler.handle(throwable); if (oldHandler) { log.warn("Stream's new uncaught exception handler is set as well as the deprecated old handler." + "The old handler will be ignored as long as a new handler is set."); } switch (action) { case REPLACE_THREAD: if (!skipThreadReplacement) { log.error("Replacing thread in the streams uncaught exception handler", throwable); replaceStreamThread(throwable); } else { log.debug("Skipping thread replacement for recoverable error"); } break; case SHUTDOWN_CLIENT: log.error("Encountered the following exception during processing " + "and the registered exception handler opted to " + action + "." + " The streams client is going to shut down now. ", throwable); closeToError(); break; case SHUTDOWN_APPLICATION: if (getNumLiveStreamThreads() == 1) { log.warn("Attempt to shut down the application requires adding a thread to communicate the shutdown. No processing will be done on this thread"); addStreamThread(); } if (throwable instanceof Error) { log.error("This option requires running threads to shut down the application." + "but the uncaught exception was an Error, which means this runtime is no " + "longer in a well-defined state. Attempting to send the shutdown command anyway.", throwable); } if (Thread.currentThread().equals(globalStreamThread) && getNumLiveStreamThreads() == 0) { log.error("Exception in global thread caused the application to attempt to shutdown." + " This action will succeed only if there is at least one StreamThread running on this client." + " Currently there are no running threads so will now close the client."); closeToError(); break; } processStreamThread(thread -> thread.sendShutdownRequest(AssignorError.SHUTDOWN_REQUESTED)); log.error("Encountered the following exception during processing " + "and sent shutdown request for the entire application.", throwable); break; } } /** * Set the listener which is triggered whenever a {@link StateStore} is being restored in order to resume * processing. * * @param globalStateRestoreListener The listener triggered when {@link StateStore} is being restored. * @throws IllegalStateException if this {@code KafkaStreams} instance has already been started. */ public void setGlobalStateRestoreListener(final StateRestoreListener globalStateRestoreListener) { synchronized (stateLock) { if (state.hasNotStarted()) { delegatingStateRestoreListener.setUserStateRestoreListener(globalStateRestoreListener); } else { throw new IllegalStateException("Can only set GlobalStateRestoreListener before calling start(). " + "Current state is: " + state); } } } /** * Set the listener which is triggered whenever a standby task is updated * * @param standbyListener The listener triggered when a standby task is updated. * @throws IllegalStateException if this {@code KafkaStreams} instance has already been started. */ public void setStandbyUpdateListener(final StandbyUpdateListener standbyListener) { synchronized (stateLock) { if (state.hasNotStarted()) { this.delegatingStandbyUpdateListener.setUserStandbyListener(standbyListener); } else { throw new IllegalStateException("Can only set StandbyUpdateListener before calling start(). " + "Current state is: " + state); } } } /** * Get read-only handle on global metrics registry, including streams client's own metrics plus * its embedded producer, consumer and admin clients' metrics. * * @return Map of all metrics. */ public Map metrics() { final Map result = new LinkedHashMap<>(); // producer and consumer clients are per-thread processStreamThread(thread -> { result.putAll(thread.producerMetrics()); result.putAll(thread.consumerMetrics()); // admin client is shared, so we can actually move it // to result.putAll(adminClient.metrics()). // we did it intentionally just for flexibility. result.putAll(thread.adminClientMetrics()); }); // global thread's consumer client if (globalStreamThread != null) { result.putAll(globalStreamThread.consumerMetrics()); } // self streams metrics result.putAll(metrics.metrics()); return Collections.unmodifiableMap(result); } /** * Class that handles stream thread transitions */ final class StreamStateListener implements StreamThread.StateListener { private final Map threadState; private GlobalStreamThread.State globalThreadState; // this lock should always be held before the state lock private final Object threadStatesLock; StreamStateListener(final Map threadState, final GlobalStreamThread.State globalThreadState) { this.threadState = threadState; this.globalThreadState = globalThreadState; this.threadStatesLock = new Object(); } /** * If all threads are up, including the global thread, set to RUNNING */ private void maybeSetRunning() { // state can be transferred to RUNNING if // 1) all threads are either RUNNING or DEAD // 2) thread is pending-shutdown and there are still other threads running final boolean hasRunningThread = threadState.values().stream().anyMatch(s -> s == StreamThread.State.RUNNING); for (final StreamThread.State state : threadState.values()) { if (state == StreamThread.State.PENDING_SHUTDOWN && hasRunningThread) continue; if (state != StreamThread.State.RUNNING && state != StreamThread.State.DEAD) { return; } } // the global state thread is relevant only if it is started. There are cases // when we don't have a global state thread at all, e.g., when we don't have global KTables if (globalThreadState != null && globalThreadState != GlobalStreamThread.State.RUNNING) { return; } setState(State.RUNNING); } @Override public synchronized void onChange(final Thread thread, final ThreadStateTransitionValidator abstractNewState, final ThreadStateTransitionValidator abstractOldState) { synchronized (threadStatesLock) { // StreamThreads first if (thread instanceof StreamThread) { final StreamThread.State newState = (StreamThread.State) abstractNewState; threadState.put(thread.getId(), newState); if (newState == StreamThread.State.PARTITIONS_REVOKED || newState == StreamThread.State.PARTITIONS_ASSIGNED) { setState(State.REBALANCING); } else if (newState == StreamThread.State.RUNNING) { maybeSetRunning(); } } else if (thread instanceof GlobalStreamThread) { // global stream thread has different invariants final GlobalStreamThread.State newState = (GlobalStreamThread.State) abstractNewState; globalThreadState = newState; if (newState == GlobalStreamThread.State.RUNNING) { maybeSetRunning(); } else if (newState == GlobalStreamThread.State.DEAD) { if (state != State.PENDING_SHUTDOWN) { log.error("Global thread has died. The streams application or client will now close to ERROR."); closeToError(); } } } } } } static final class DelegatingStateRestoreListener implements StateRestoreListener { private StateRestoreListener userStateRestoreListener; private void throwOnFatalException(final Exception fatalUserException, final TopicPartition topicPartition, final String storeName) { throw new StreamsException( String.format("Fatal user code error in store restore listener for store %s, partition %s.", storeName, topicPartition), fatalUserException); } void setUserStateRestoreListener(final StateRestoreListener userStateRestoreListener) { this.userStateRestoreListener = userStateRestoreListener; } @Override public void onRestoreStart(final TopicPartition topicPartition, final String storeName, final long startingOffset, final long endingOffset) { if (userStateRestoreListener != null) { try { userStateRestoreListener.onRestoreStart(topicPartition, storeName, startingOffset, endingOffset); } catch (final Exception fatalUserException) { throwOnFatalException(fatalUserException, topicPartition, storeName); } } } @Override public void onBatchRestored(final TopicPartition topicPartition, final String storeName, final long batchEndOffset, final long numRestored) { if (userStateRestoreListener != null) { try { userStateRestoreListener.onBatchRestored(topicPartition, storeName, batchEndOffset, numRestored); } catch (final Exception fatalUserException) { throwOnFatalException(fatalUserException, topicPartition, storeName); } } } @Override public void onRestoreEnd(final TopicPartition topicPartition, final String storeName, final long totalRestored) { if (userStateRestoreListener != null) { try { userStateRestoreListener.onRestoreEnd(topicPartition, storeName, totalRestored); } catch (final Exception fatalUserException) { throwOnFatalException(fatalUserException, topicPartition, storeName); } } } @Override public void onRestoreSuspended(final TopicPartition topicPartition, final String storeName, final long totalRestored) { if (userStateRestoreListener != null) { try { userStateRestoreListener.onRestoreSuspended(topicPartition, storeName, totalRestored); } catch (final Exception fatalUserException) { throwOnFatalException(fatalUserException, topicPartition, storeName); } } } } final static class DelegatingStandbyUpdateListener implements StandbyUpdateListener { private StandbyUpdateListener userStandbyListener; private void throwOnFatalException(final Exception fatalUserException, final TopicPartition topicPartition, final String storeName) { throw new StreamsException( String.format("Fatal user code error in standby update listener for store %s, partition %s.", storeName, topicPartition), fatalUserException); } @Override public void onUpdateStart(final TopicPartition topicPartition, final String storeName, final long startingOffset) { if (userStandbyListener != null) { try { userStandbyListener.onUpdateStart(topicPartition, storeName, startingOffset); } catch (final Exception fatalUserException) { throwOnFatalException(fatalUserException, topicPartition, storeName); } } } @Override public void onBatchLoaded(final TopicPartition topicPartition, final String storeName, final TaskId taskId, final long batchEndOffset, final long batchSize, final long currentEndOffset) { if (userStandbyListener != null) { try { userStandbyListener.onBatchLoaded(topicPartition, storeName, taskId, batchEndOffset, batchSize, currentEndOffset); } catch (final Exception fatalUserException) { throwOnFatalException(fatalUserException, topicPartition, storeName); } } } @Override public void onUpdateSuspended(final TopicPartition topicPartition, final String storeName, final long storeOffset, final long currentEndOffset, final SuspendReason reason) { if (userStandbyListener != null) { try { userStandbyListener.onUpdateSuspended(topicPartition, storeName, storeOffset, currentEndOffset, reason); } catch (final Exception fatalUserException) { throwOnFatalException(fatalUserException, topicPartition, storeName); } } } void setUserStandbyListener(final StandbyUpdateListener userStandbyListener) { this.userStandbyListener = userStandbyListener; } } /** * Create a {@code KafkaStreams} instance. *

* Note: even if you never call {@link #start()} on a {@code KafkaStreams} instance, * you still must {@link #close()} it to avoid resource leaks. * * @param topology the topology specifying the computational logic * @param props properties for {@link StreamsConfig} * @throws StreamsException if any fatal error occurs */ public KafkaStreams(final Topology topology, final Properties props) { this(topology, new StreamsConfig(props)); } /** * Create a {@code KafkaStreams} instance. *

* Note: even if you never call {@link #start()} on a {@code KafkaStreams} instance, * you still must {@link #close()} it to avoid resource leaks. * * @param topology the topology specifying the computational logic * @param props properties for {@link StreamsConfig} * @param clientSupplier the Kafka clients supplier which provides underlying producer and consumer clients * for the new {@code KafkaStreams} instance * @throws StreamsException if any fatal error occurs */ public KafkaStreams(final Topology topology, final Properties props, final KafkaClientSupplier clientSupplier) { this(topology, new StreamsConfig(props), clientSupplier, Time.SYSTEM); } /** * Create a {@code KafkaStreams} instance. *

* Note: even if you never call {@link #start()} on a {@code KafkaStreams} instance, * you still must {@link #close()} it to avoid resource leaks. * * @param topology the topology specifying the computational logic * @param props properties for {@link StreamsConfig} * @param time {@code Time} implementation; cannot be null * @throws StreamsException if any fatal error occurs */ public KafkaStreams(final Topology topology, final Properties props, final Time time) { this(topology, new StreamsConfig(props), time); } /** * Create a {@code KafkaStreams} instance. *

* Note: even if you never call {@link #start()} on a {@code KafkaStreams} instance, * you still must {@link #close()} it to avoid resource leaks. * * @param topology the topology specifying the computational logic * @param props properties for {@link StreamsConfig} * @param clientSupplier the Kafka clients supplier which provides underlying producer and consumer clients * for the new {@code KafkaStreams} instance * @param time {@code Time} implementation; cannot be null * @throws StreamsException if any fatal error occurs */ public KafkaStreams(final Topology topology, final Properties props, final KafkaClientSupplier clientSupplier, final Time time) { this(topology, new StreamsConfig(props), clientSupplier, time); } /** * Create a {@code KafkaStreams} instance. *

* Note: even if you never call {@link #start()} on a {@code KafkaStreams} instance, * you still must {@link #close()} it to avoid resource leaks. * * @param topology the topology specifying the computational logic * @param applicationConfigs configs for Kafka Streams * @throws StreamsException if any fatal error occurs */ public KafkaStreams(final Topology topology, final StreamsConfig applicationConfigs) { this(topology, applicationConfigs, applicationConfigs.getKafkaClientSupplier()); } /** * Create a {@code KafkaStreams} instance. *

* Note: even if you never call {@link #start()} on a {@code KafkaStreams} instance, * you still must {@link #close()} it to avoid resource leaks. * * @param topology the topology specifying the computational logic * @param applicationConfigs configs for Kafka Streams * @param clientSupplier the Kafka clients supplier which provides underlying producer and consumer clients * for the new {@code KafkaStreams} instance * @throws StreamsException if any fatal error occurs */ public KafkaStreams(final Topology topology, final StreamsConfig applicationConfigs, final KafkaClientSupplier clientSupplier) { this(new TopologyMetadata(topology.internalTopologyBuilder, applicationConfigs), applicationConfigs, clientSupplier); } /** * Create a {@code KafkaStreams} instance. *

* Note: even if you never call {@link #start()} on a {@code KafkaStreams} instance, * you still must {@link #close()} it to avoid resource leaks. * * @param topology the topology specifying the computational logic * @param applicationConfigs configs for Kafka Streams * @param time {@code Time} implementation; cannot be null * @throws StreamsException if any fatal error occurs */ public KafkaStreams(final Topology topology, final StreamsConfig applicationConfigs, final Time time) { this(new TopologyMetadata(topology.internalTopologyBuilder, applicationConfigs), applicationConfigs, applicationConfigs.getKafkaClientSupplier(), time); } private KafkaStreams(final Topology topology, final StreamsConfig applicationConfigs, final KafkaClientSupplier clientSupplier, final Time time) throws StreamsException { this(new TopologyMetadata(topology.internalTopologyBuilder, applicationConfigs), applicationConfigs, clientSupplier, time); } protected KafkaStreams(final TopologyMetadata topologyMetadata, final StreamsConfig applicationConfigs, final KafkaClientSupplier clientSupplier) throws StreamsException { this(topologyMetadata, applicationConfigs, clientSupplier, Time.SYSTEM); } @SuppressWarnings("this-escape") private KafkaStreams(final TopologyMetadata topologyMetadata, final StreamsConfig applicationConfigs, final KafkaClientSupplier clientSupplier, final Time time) throws StreamsException { this.applicationConfigs = applicationConfigs; this.time = time; this.topologyMetadata = topologyMetadata; this.topologyMetadata.buildAndRewriteTopology(); final boolean hasGlobalTopology = topologyMetadata.hasGlobalTopology(); try { stateDirectory = new StateDirectory(applicationConfigs, time, topologyMetadata.hasPersistentStores(), topologyMetadata.hasNamedTopologies()); processId = stateDirectory.initializeProcessId(); } catch (final ProcessorStateException fatal) { throw new StreamsException(fatal); } // The application ID is a required config and hence should always have value final String userClientId = applicationConfigs.getString(StreamsConfig.CLIENT_ID_CONFIG); final String applicationId = applicationConfigs.getString(StreamsConfig.APPLICATION_ID_CONFIG); if (userClientId.length() <= 0) { clientId = applicationId + "-" + processId; } else { clientId = userClientId; } final LogContext logContext = new LogContext(String.format("stream-client [%s] ", clientId)); this.log = logContext.logger(getClass()); topologyMetadata.setLog(logContext); // use client id instead of thread client id since this admin client may be shared among threads this.clientSupplier = clientSupplier; adminClient = clientSupplier.getAdmin(applicationConfigs.getAdminConfigs(ClientUtils.getSharedAdminClientId(clientId))); log.info("Kafka Streams version: {}", ClientMetrics.version()); log.info("Kafka Streams commit ID: {}", ClientMetrics.commitId()); metrics = getMetrics(applicationConfigs, time, clientId); streamsMetrics = new StreamsMetricsImpl( metrics, clientId, applicationConfigs.getString(StreamsConfig.BUILT_IN_METRICS_VERSION_CONFIG), time ); ClientMetrics.addVersionMetric(streamsMetrics); ClientMetrics.addCommitIdMetric(streamsMetrics); ClientMetrics.addApplicationIdMetric(streamsMetrics, applicationConfigs.getString(StreamsConfig.APPLICATION_ID_CONFIG)); ClientMetrics.addTopologyDescriptionMetric(streamsMetrics, (metricsConfig, now) -> this.topologyMetadata.topologyDescriptionString()); ClientMetrics.addStateMetric(streamsMetrics, (metricsConfig, now) -> state); threads = Collections.synchronizedList(new LinkedList<>()); ClientMetrics.addNumAliveStreamThreadMetric(streamsMetrics, (metricsConfig, now) -> getNumLiveStreamThreads()); streamsMetadataState = new StreamsMetadataState( this.topologyMetadata, parseHostInfo(applicationConfigs.getString(StreamsConfig.APPLICATION_SERVER_CONFIG)), logContext ); oldHandler = false; streamsUncaughtExceptionHandler = this::defaultStreamsUncaughtExceptionHandler; delegatingStateRestoreListener = new DelegatingStateRestoreListener(); delegatingStandbyUpdateListener = new DelegatingStandbyUpdateListener(); totalCacheSize = getTotalCacheSize(applicationConfigs); final int numStreamThreads = topologyMetadata.getNumStreamThreads(applicationConfigs); final long cacheSizePerThread = getCacheSizePerThread(numStreamThreads); GlobalStreamThread.State globalThreadState = null; if (hasGlobalTopology) { final String globalThreadId = clientId + "-GlobalStreamThread"; globalStreamThread = new GlobalStreamThread( topologyMetadata.globalTaskTopology(), applicationConfigs, clientSupplier.getGlobalConsumer(applicationConfigs.getGlobalConsumerConfigs(clientId)), stateDirectory, cacheSizePerThread, streamsMetrics, time, globalThreadId, delegatingStateRestoreListener, exception -> defaultStreamsUncaughtExceptionHandler(exception, false) ); globalThreadState = globalStreamThread.state(); } threadState = new HashMap<>(numStreamThreads); streamStateListener = new StreamStateListener(threadState, globalThreadState); final GlobalStateStoreProvider globalStateStoreProvider = new GlobalStateStoreProvider(this.topologyMetadata.globalStateStores()); if (hasGlobalTopology) { globalStreamThread.setStateListener(streamStateListener); } queryableStoreProvider = new QueryableStoreProvider(globalStateStoreProvider); for (int i = 1; i <= numStreamThreads; i++) { createAndAddStreamThread(cacheSizePerThread, i); } stateDirCleaner = setupStateDirCleaner(); rocksDBMetricsRecordingService = maybeCreateRocksDBMetricsRecordingService(clientId, applicationConfigs); } private StreamThread createAndAddStreamThread(final long cacheSizePerThread, final int threadIdx) { final StreamThread streamThread = StreamThread.create( topologyMetadata, applicationConfigs, clientSupplier, adminClient, processId, clientId, streamsMetrics, time, streamsMetadataState, cacheSizePerThread, stateDirectory, delegatingStateRestoreListener, delegatingStandbyUpdateListener, threadIdx, KafkaStreams.this::closeToError, streamsUncaughtExceptionHandler ); streamThread.setStateListener(streamStateListener); threads.add(streamThread); threadState.put(streamThread.getId(), streamThread.state()); queryableStoreProvider.addStoreProviderForThread(streamThread.getName(), new StreamThreadStateStoreProvider(streamThread)); return streamThread; } static Metrics getMetrics(final StreamsConfig config, final Time time, final String clientId) { final MetricConfig metricConfig = new MetricConfig() .samples(config.getInt(StreamsConfig.METRICS_NUM_SAMPLES_CONFIG)) .recordLevel(Sensor.RecordingLevel.forName(config.getString(StreamsConfig.METRICS_RECORDING_LEVEL_CONFIG))) .timeWindow(config.getLong(StreamsConfig.METRICS_SAMPLE_WINDOW_MS_CONFIG), TimeUnit.MILLISECONDS); final List reporters = CommonClientConfigs.metricsReporters(clientId, config); final MetricsContext metricsContext = new KafkaMetricsContext(JMX_PREFIX, config.originalsWithPrefix(CommonClientConfigs.METRICS_CONTEXT_PREFIX)); return new Metrics(metricConfig, reporters, time, metricsContext); } /** * Adds and starts a stream thread in addition to the stream threads that are already running in this * Kafka Streams client. *

* Since the number of stream threads increases, the sizes of the caches in the new stream thread * and the existing stream threads are adapted so that the sum of the cache sizes over all stream * threads does not exceed the total cache size specified in configuration * {@link StreamsConfig#STATESTORE_CACHE_MAX_BYTES_CONFIG}. *

* Stream threads can only be added if this Kafka Streams client is in state RUNNING or REBALANCING. * * @return name of the added stream thread or empty if a new stream thread could not be added */ public Optional addStreamThread() { if (isRunningOrRebalancing()) { final StreamThread streamThread; synchronized (changeThreadCount) { final int threadIdx = getNextThreadIndex(); final int numLiveThreads = getNumLiveStreamThreads(); final long cacheSizePerThread = getCacheSizePerThread(numLiveThreads + 1); log.info("Adding StreamThread-{}, there will now be {} live threads and the new cache size per thread is {}", threadIdx, numLiveThreads + 1, cacheSizePerThread); resizeThreadCache(cacheSizePerThread); // Creating thread should hold the lock in order to avoid duplicate thread index. // If the duplicate index happen, the metadata of thread may be duplicate too. streamThread = createAndAddStreamThread(cacheSizePerThread, threadIdx); } synchronized (stateLock) { if (isRunningOrRebalancing()) { streamThread.start(); return Optional.of(streamThread.getName()); } else { log.warn("Terminating the new thread because the Kafka Streams client is in state {}", state); streamThread.shutdown(); threads.remove(streamThread); final long cacheSizePerThread = getCacheSizePerThread(getNumLiveStreamThreads()); log.info("Resizing thread cache due to terminating added thread, new cache size per thread is {}", cacheSizePerThread); resizeThreadCache(cacheSizePerThread); return Optional.empty(); } } } else { log.warn("Cannot add a stream thread when Kafka Streams client is in state {}", state); return Optional.empty(); } } /** * Removes one stream thread out of the running stream threads from this Kafka Streams client. *

* The removed stream thread is gracefully shut down. This method does not specify which stream * thread is shut down. *

* Since the number of stream threads decreases, the sizes of the caches in the remaining stream * threads are adapted so that the sum of the cache sizes over all stream threads equals the total * cache size specified in configuration {@link StreamsConfig#STATESTORE_CACHE_MAX_BYTES_CONFIG}. * * @return name of the removed stream thread or empty if a stream thread could not be removed because * no stream threads are alive */ public Optional removeStreamThread() { return removeStreamThread(Long.MAX_VALUE); } /** * Removes one stream thread out of the running stream threads from this Kafka Streams client. *

* The removed stream thread is gracefully shut down. This method does not specify which stream * thread is shut down. *

* Since the number of stream threads decreases, the sizes of the caches in the remaining stream * threads are adapted so that the sum of the cache sizes over all stream threads equals the total * cache size specified in configuration {@link StreamsConfig#STATESTORE_CACHE_MAX_BYTES_CONFIG}. * * @param timeout The length of time to wait for the thread to shut down * @throws org.apache.kafka.common.errors.TimeoutException if the thread does not stop in time * @return name of the removed stream thread or empty if a stream thread could not be removed because * no stream threads are alive */ public Optional removeStreamThread(final Duration timeout) { final String msgPrefix = prepareMillisCheckFailMsgPrefix(timeout, "timeout"); final long timeoutMs = validateMillisecondDuration(timeout, msgPrefix); return removeStreamThread(timeoutMs); } private Optional removeStreamThread(final long timeoutMs) throws TimeoutException { final long startMs = time.milliseconds(); if (isRunningOrRebalancing()) { synchronized (changeThreadCount) { // make a copy of threads to avoid holding lock for (final StreamThread streamThread : new ArrayList<>(threads)) { final boolean callingThreadIsNotCurrentStreamThread = !streamThread.getName().equals(Thread.currentThread().getName()); if (streamThread.isThreadAlive() && (callingThreadIsNotCurrentStreamThread || getNumLiveStreamThreads() == 1)) { log.info("Removing StreamThread " + streamThread.getName()); final Optional groupInstanceID = streamThread.getGroupInstanceID(); streamThread.requestLeaveGroupDuringShutdown(); streamThread.shutdown(); if (!streamThread.getName().equals(Thread.currentThread().getName())) { final long remainingTimeMs = timeoutMs - (time.milliseconds() - startMs); if (remainingTimeMs <= 0 || !streamThread.waitOnThreadState(StreamThread.State.DEAD, remainingTimeMs)) { log.warn("{} did not shutdown in the allotted time.", streamThread.getName()); // Don't remove from threads until shutdown is complete. We will trim it from the // list once it reaches DEAD, and if for some reason it's hanging indefinitely in the // shutdown then we should just consider this thread.id to be burned } else { log.info("Successfully removed {} in {}ms", streamThread.getName(), time.milliseconds() - startMs); threads.remove(streamThread); queryableStoreProvider.removeStoreProviderForThread(streamThread.getName()); } } else { log.info("{} is the last remaining thread and must remove itself, therefore we cannot wait " + "for it to complete shutdown as this will result in deadlock.", streamThread.getName()); } final long cacheSizePerThread = getCacheSizePerThread(getNumLiveStreamThreads()); log.info("Resizing thread cache due to thread removal, new cache size per thread is {}", cacheSizePerThread); resizeThreadCache(cacheSizePerThread); if (groupInstanceID.isPresent() && callingThreadIsNotCurrentStreamThread) { final MemberToRemove memberToRemove = new MemberToRemove(groupInstanceID.get()); final Collection membersToRemove = Collections.singletonList(memberToRemove); final RemoveMembersFromConsumerGroupResult removeMembersFromConsumerGroupResult = adminClient.removeMembersFromConsumerGroup( applicationConfigs.getString(StreamsConfig.APPLICATION_ID_CONFIG), new RemoveMembersFromConsumerGroupOptions(membersToRemove) ); try { final long remainingTimeMs = timeoutMs - (time.milliseconds() - startMs); removeMembersFromConsumerGroupResult.memberResult(memberToRemove).get(remainingTimeMs, TimeUnit.MILLISECONDS); } catch (final java.util.concurrent.TimeoutException exception) { log.error( String.format( "Could not remove static member %s from consumer group %s due to a timeout:", groupInstanceID.get(), applicationConfigs.getString(StreamsConfig.APPLICATION_ID_CONFIG) ), exception ); throw new TimeoutException(exception.getMessage(), exception); } catch (final InterruptedException e) { Thread.currentThread().interrupt(); } catch (final ExecutionException exception) { log.error( String.format( "Could not remove static member %s from consumer group %s due to:", groupInstanceID.get(), applicationConfigs.getString(StreamsConfig.APPLICATION_ID_CONFIG) ), exception ); throw new StreamsException( "Could not remove static member " + groupInstanceID.get() + " from consumer group " + applicationConfigs.getString(StreamsConfig.APPLICATION_ID_CONFIG) + " for the following reason: ", exception.getCause() ); } } final long remainingTimeMs = timeoutMs - (time.milliseconds() - startMs); if (remainingTimeMs <= 0) { throw new TimeoutException("Thread " + streamThread.getName() + " did not stop in the allotted time"); } return Optional.of(streamThread.getName()); } } } log.warn("There are no threads eligible for removal"); } else { log.warn("Cannot remove a stream thread when Kafka Streams client is in state " + state()); } return Optional.empty(); } /* * Takes a snapshot and counts the number of stream threads which are not in PENDING_SHUTDOWN or DEAD * * note: iteration over SynchronizedList is not thread safe so it must be manually synchronized. However, we may * require other locks when looping threads and it could cause deadlock. Hence, we create a copy to avoid holding * threads lock when looping threads. * @return number of alive stream threads */ private int getNumLiveStreamThreads() { final AtomicInteger numLiveThreads = new AtomicInteger(0); synchronized (threads) { processStreamThread(thread -> { if (thread.state() == StreamThread.State.DEAD) { log.debug("Trimming thread {} from the threads list since it's state is {}", thread.getName(), StreamThread.State.DEAD); threads.remove(thread); } else if (thread.state() == StreamThread.State.PENDING_SHUTDOWN) { log.debug("Skipping thread {} from num live threads computation since it's state is {}", thread.getName(), StreamThread.State.PENDING_SHUTDOWN); } else { numLiveThreads.incrementAndGet(); } }); return numLiveThreads.get(); } } private int getNextThreadIndex() { final HashSet allLiveThreadNames = new HashSet<>(); final AtomicInteger maxThreadId = new AtomicInteger(1); synchronized (threads) { processStreamThread(thread -> { // trim any DEAD threads from the list so we can reuse the thread.id // this is only safe to do once the thread has fully completed shutdown if (thread.state() == StreamThread.State.DEAD) { threads.remove(thread); } else { allLiveThreadNames.add(thread.getName()); // Assume threads are always named with the "-StreamThread-" suffix final int threadId = Integer.parseInt(thread.getName().substring(thread.getName().lastIndexOf("-") + 1)); if (threadId > maxThreadId.get()) { maxThreadId.set(threadId); } } }); final String baseName = clientId + "-StreamThread-"; for (int i = 1; i <= maxThreadId.get(); i++) { final String name = baseName + i; if (!allLiveThreadNames.contains(name)) { return i; } } // It's safe to use threads.size() rather than getNumLiveStreamThreads() to infer the number of threads // here since we trimmed any DEAD threads earlier in this method while holding the lock return threads.size() + 1; } } private long getCacheSizePerThread(final int numStreamThreads) { if (numStreamThreads == 0) { return totalCacheSize; } return totalCacheSize / (numStreamThreads + (topologyMetadata.hasGlobalTopology() ? 1 : 0)); } private void resizeThreadCache(final long cacheSizePerThread) { processStreamThread(thread -> thread.resizeCache(cacheSizePerThread)); if (globalStreamThread != null) { globalStreamThread.resize(cacheSizePerThread); } } private ScheduledExecutorService setupStateDirCleaner() { return Executors.newSingleThreadScheduledExecutor(r -> { final Thread thread = new Thread(r, clientId + "-CleanupThread"); thread.setDaemon(true); return thread; }); } private static ScheduledExecutorService maybeCreateRocksDBMetricsRecordingService(final String clientId, final StreamsConfig config) { if (RecordingLevel.forName(config.getString(StreamsConfig.METRICS_RECORDING_LEVEL_CONFIG)) == RecordingLevel.DEBUG) { return Executors.newSingleThreadScheduledExecutor(r -> { final Thread thread = new Thread(r, clientId + "-RocksDBMetricsRecordingTrigger"); thread.setDaemon(true); return thread; }); } return null; } private static HostInfo parseHostInfo(final String endPoint) { final HostInfo hostInfo = HostInfo.buildFromEndpoint(endPoint); if (hostInfo == null) { return StreamsMetadataState.UNKNOWN_HOST; } else { return hostInfo; } } /** * Start the {@code KafkaStreams} instance by starting all its threads. * This function is expected to be called only once during the life cycle of the client. *

* Because threads are started in the background, this method does not block. * However, if you have global stores in your topology, this method blocks until all global stores are restored. * As a consequence, any fatal exception that happens during processing is by default only logged. * If you want to be notified about dying threads, you can * {@link #setUncaughtExceptionHandler(Thread.UncaughtExceptionHandler) register an uncaught exception handler} * before starting the {@code KafkaStreams} instance. *

* Note, for brokers with version {@code 0.9.x} or lower, the broker version cannot be checked. * There will be no error and the client will hang and retry to verify the broker version until it * {@link StreamsConfig#REQUEST_TIMEOUT_MS_CONFIG times out}. * @throws IllegalStateException if process was already started * @throws StreamsException if the Kafka brokers have version 0.10.0.x or * if {@link StreamsConfig#PROCESSING_GUARANTEE_CONFIG exactly-once} is enabled for pre 0.11.0.x brokers */ public synchronized void start() throws IllegalStateException, StreamsException { if (setState(State.REBALANCING)) { log.debug("Starting Streams client"); if (globalStreamThread != null) { globalStreamThread.start(); } final int numThreads = processStreamThread(StreamThread::start); log.info("Started {} stream threads", numThreads); final Long cleanupDelay = applicationConfigs.getLong(StreamsConfig.STATE_CLEANUP_DELAY_MS_CONFIG); stateDirCleaner.scheduleAtFixedRate(() -> { // we do not use lock here since we only read on the value and act on it if (state == State.RUNNING) { stateDirectory.cleanRemovedTasks(cleanupDelay); } }, cleanupDelay, cleanupDelay, TimeUnit.MILLISECONDS); final long recordingDelay = 0; final long recordingInterval = 1; if (rocksDBMetricsRecordingService != null) { rocksDBMetricsRecordingService.scheduleAtFixedRate( streamsMetrics.rocksDBMetricsRecordingTrigger(), recordingDelay, recordingInterval, TimeUnit.MINUTES ); } } else { throw new IllegalStateException("The client is either already started or already stopped, cannot re-start"); } } /** * Class that handles options passed in case of {@code KafkaStreams} instance scale down */ public static class CloseOptions { private Duration timeout = Duration.ofMillis(Long.MAX_VALUE); private boolean leaveGroup = false; public CloseOptions timeout(final Duration timeout) { this.timeout = timeout; return this; } public CloseOptions leaveGroup(final boolean leaveGroup) { this.leaveGroup = leaveGroup; return this; } } /** * Shutdown this {@code KafkaStreams} instance by signaling all the threads to stop, and then wait for them to join. * This will block until all threads have stopped. */ public void close() { close(Long.MAX_VALUE, false); } private Thread shutdownHelper(final boolean error, final long timeoutMs, final boolean leaveGroup) { stateDirCleaner.shutdownNow(); if (rocksDBMetricsRecordingService != null) { rocksDBMetricsRecordingService.shutdownNow(); } // wait for all threads to join in a separate thread; // save the current thread so that if it is a stream thread // we don't attempt to join it and cause a deadlock return new Thread(() -> { // notify all the threads to stop; avoid deadlocks by stopping any // further state reports from the thread since we're shutting down int numStreamThreads = processStreamThread(StreamThread::shutdown); log.info("Shutting down {} stream threads", numStreamThreads); topologyMetadata.wakeupThreads(); numStreamThreads = processStreamThread(thread -> { try { if (!thread.isRunning()) { log.debug("Shutdown {} complete", thread.getName()); thread.join(); } } catch (final InterruptedException ex) { log.warn("Shutdown {} interrupted", thread.getName()); Thread.currentThread().interrupt(); } }); if (leaveGroup) { processStreamThread(streamThreadLeaveConsumerGroup(timeoutMs)); } log.info("Shutdown {} stream threads complete", numStreamThreads); if (globalStreamThread != null) { log.info("Shutting down the global stream threads"); globalStreamThread.shutdown(); } if (globalStreamThread != null && !globalStreamThread.stillRunning()) { try { globalStreamThread.join(); } catch (final InterruptedException e) { log.warn("Shutdown the global stream thread interrupted"); Thread.currentThread().interrupt(); } globalStreamThread = null; log.info("Shutdown global stream threads complete"); } stateDirectory.close(); adminClient.close(); streamsMetrics.removeAllClientLevelSensorsAndMetrics(); metrics.close(); if (!error) { setState(State.NOT_RUNNING); } else { setState(State.ERROR); } }, clientId + "-CloseThread"); } private boolean close(final long timeoutMs, final boolean leaveGroup) { if (state.hasCompletedShutdown()) { log.info("Streams client is already in the terminal {} state, all resources are closed and the client has stopped.", state); return true; } if (state.isShuttingDown()) { log.info("Streams client is in {}, all resources are being closed and the client will be stopped.", state); if (state == State.PENDING_ERROR && waitOnState(State.ERROR, timeoutMs)) { log.info("Streams client stopped to ERROR completely"); return true; } else if (state == State.PENDING_SHUTDOWN && waitOnState(State.NOT_RUNNING, timeoutMs)) { log.info("Streams client stopped to NOT_RUNNING completely"); return true; } else { log.warn("Streams client cannot transition to {}} completely within the timeout", state == State.PENDING_SHUTDOWN ? State.NOT_RUNNING : State.ERROR); return false; } } if (!setState(State.PENDING_SHUTDOWN)) { // if we can't transition to PENDING_SHUTDOWN but not because we're already shutting down, then it must be fatal log.error("Failed to transition to PENDING_SHUTDOWN, current state is {}", state); throw new StreamsException("Failed to shut down while in state " + state); } else { final Thread shutdownThread = shutdownHelper(false, timeoutMs, leaveGroup); shutdownThread.setDaemon(true); shutdownThread.start(); } if (waitOnState(State.NOT_RUNNING, timeoutMs)) { log.info("Streams client stopped completely"); return true; } else { log.info("Streams client cannot stop completely within the {}ms timeout", timeoutMs); return false; } } private void closeToError() { if (!setState(State.PENDING_ERROR)) { log.info("Skipping shutdown since we are already in " + state()); } else { final Thread shutdownThread = shutdownHelper(true, -1, false); shutdownThread.setDaemon(true); shutdownThread.start(); } } /** * Shutdown this {@code KafkaStreams} by signaling all the threads to stop, and then wait up to the timeout for the * threads to join. * A {@code timeout} of Duration.ZERO (or any other zero duration) makes the close operation asynchronous. * Negative-duration timeouts are rejected. * * @param timeout how long to wait for the threads to shutdown * @return {@code true} if all threads were successfully stopped—{@code false} if the timeout was reached * before all threads stopped * Note that this method must not be called in the {@link StateListener#onChange(KafkaStreams.State, KafkaStreams.State)} callback of {@link StateListener}. * @throws IllegalArgumentException if {@code timeout} can't be represented as {@code long milliseconds} */ public synchronized boolean close(final Duration timeout) throws IllegalArgumentException { final String msgPrefix = prepareMillisCheckFailMsgPrefix(timeout, "timeout"); final long timeoutMs = validateMillisecondDuration(timeout, msgPrefix); if (timeoutMs < 0) { throw new IllegalArgumentException("Timeout can't be negative."); } log.debug("Stopping Streams client with timeoutMillis = {} ms.", timeoutMs); return close(timeoutMs, false); } /** * Shutdown this {@code KafkaStreams} by signaling all the threads to stop, and then wait up to the timeout for the * threads to join. * @param options contains timeout to specify how long to wait for the threads to shutdown, and a flag leaveGroup to * trigger consumer leave call * @return {@code true} if all threads were successfully stopped—{@code false} if the timeout was reached * before all threads stopped * Note that this method must not be called in the {@link StateListener#onChange(KafkaStreams.State, KafkaStreams.State)} callback of {@link StateListener}. * @throws IllegalArgumentException if {@code timeout} can't be represented as {@code long milliseconds} */ public synchronized boolean close(final CloseOptions options) throws IllegalArgumentException { Objects.requireNonNull(options, "options cannot be null"); final String msgPrefix = prepareMillisCheckFailMsgPrefix(options.timeout, "timeout"); final long timeoutMs = validateMillisecondDuration(options.timeout, msgPrefix); if (timeoutMs < 0) { throw new IllegalArgumentException("Timeout can't be negative."); } log.debug("Stopping Streams client with timeoutMillis = {} ms.", timeoutMs); return close(timeoutMs, options.leaveGroup); } private Consumer streamThreadLeaveConsumerGroup(final long remainingTimeMs) { return thread -> { final Optional groupInstanceId = thread.getGroupInstanceID(); if (groupInstanceId.isPresent()) { log.debug("Sending leave group trigger to removing instance from consumer group: {}.", groupInstanceId.get()); final MemberToRemove memberToRemove = new MemberToRemove(groupInstanceId.get()); final Collection membersToRemove = Collections.singletonList(memberToRemove); final RemoveMembersFromConsumerGroupResult removeMembersFromConsumerGroupResult = adminClient .removeMembersFromConsumerGroup( applicationConfigs.getString(StreamsConfig.APPLICATION_ID_CONFIG), new RemoveMembersFromConsumerGroupOptions(membersToRemove) ); try { removeMembersFromConsumerGroupResult.memberResult(memberToRemove) .get(remainingTimeMs, TimeUnit.MILLISECONDS); } catch (final Exception e) { final String msg = String.format("Could not remove static member %s from consumer group %s.", groupInstanceId.get(), applicationConfigs.getString(StreamsConfig.APPLICATION_ID_CONFIG)); log.error(msg, e); } } }; } /** * Do a clean up of the local {@link StateStore} directory ({@link StreamsConfig#STATE_DIR_CONFIG}) by deleting all * data with regard to the {@link StreamsConfig#APPLICATION_ID_CONFIG application ID}. *

* May only be called either before this {@code KafkaStreams} instance is {@link #start() started} or after the * instance is {@link #close() closed}. *

* Calling this method triggers a restore of local {@link StateStore}s on the next {@link #start() application start}. * * @throws IllegalStateException if this {@code KafkaStreams} instance has been started and hasn't fully shut down * @throws StreamsException if cleanup failed */ public void cleanUp() { if (!(state.hasNotStarted() || state.hasCompletedShutdown())) { throw new IllegalStateException("Cannot clean up while running."); } stateDirectory.clean(); } /** * Find all currently running {@code KafkaStreams} instances (potentially remotely) that use the same * {@link StreamsConfig#APPLICATION_ID_CONFIG application ID} as this instance (i.e., all instances that belong to * the same Kafka Streams application) and return {@link StreamsMetadata} for each discovered instance. *

* Note: this is a point in time view and it may change due to partition reassignment. * * @return {@link StreamsMetadata} for each {@code KafkaStreams} instances of this application * @deprecated since 3.0.0 use {@link KafkaStreams#metadataForAllStreamsClients} */ @Deprecated public Collection allMetadata() { validateIsRunningOrRebalancing(); return streamsMetadataState.getAllMetadata().stream().map(streamsMetadata -> new org.apache.kafka.streams.state.StreamsMetadata(streamsMetadata.hostInfo(), streamsMetadata.stateStoreNames(), streamsMetadata.topicPartitions(), streamsMetadata.standbyStateStoreNames(), streamsMetadata.standbyTopicPartitions())) .collect(Collectors.toSet()); } /** * Find all currently running {@code KafkaStreams} instances (potentially remotely) that use the same * {@link StreamsConfig#APPLICATION_ID_CONFIG application ID} as this instance (i.e., all instances that belong to * the same Kafka Streams application) and return {@link StreamsMetadata} for each discovered instance. *

* Note: this is a point in time view and it may change due to partition reassignment. * * @return {@link StreamsMetadata} for each {@code KafkaStreams} instances of this application */ public Collection metadataForAllStreamsClients() { validateIsRunningOrRebalancing(); return streamsMetadataState.getAllMetadata(); } /** * Find all currently running {@code KafkaStreams} instances (potentially remotely) that *

    *
  • use the same {@link StreamsConfig#APPLICATION_ID_CONFIG application ID} as this instance (i.e., all * instances that belong to the same Kafka Streams application)
  • *
  • and that contain a {@link StateStore} with the given {@code storeName}
  • *
* and return {@link StreamsMetadata} for each discovered instance. *

* Note: this is a point in time view and it may change due to partition reassignment. * * @param storeName the {@code storeName} to find metadata for * @return {@link StreamsMetadata} for each {@code KafkaStreams} instances with the provide {@code storeName} of * this application * @deprecated since 3.0.0 use {@link KafkaStreams#streamsMetadataForStore} instead */ @Deprecated public Collection allMetadataForStore(final String storeName) { validateIsRunningOrRebalancing(); return streamsMetadataState.getAllMetadataForStore(storeName).stream().map(streamsMetadata -> new org.apache.kafka.streams.state.StreamsMetadata(streamsMetadata.hostInfo(), streamsMetadata.stateStoreNames(), streamsMetadata.topicPartitions(), streamsMetadata.standbyStateStoreNames(), streamsMetadata.standbyTopicPartitions())) .collect(Collectors.toSet()); } /** * Find all currently running {@code KafkaStreams} instances (potentially remotely) that *

    *
  • use the same {@link StreamsConfig#APPLICATION_ID_CONFIG application ID} as this instance (i.e., all * instances that belong to the same Kafka Streams application)
  • *
  • and that contain a {@link StateStore} with the given {@code storeName}
  • *
* and return {@link StreamsMetadata} for each discovered instance. *

* Note: this is a point in time view and it may change due to partition reassignment. * * @param storeName the {@code storeName} to find metadata for * @return {@link StreamsMetadata} for each {@code KafkaStreams} instances with the provide {@code storeName} of * this application */ public Collection streamsMetadataForStore(final String storeName) { validateIsRunningOrRebalancing(); return streamsMetadataState.getAllMetadataForStore(storeName); } /** * Finds the metadata containing the active hosts and standby hosts where the key being queried would reside. * * @param storeName the {@code storeName} to find metadata for * @param key the key to find metadata for * @param keySerializer serializer for the key * @param key type * Returns {@link KeyQueryMetadata} containing all metadata about hosting the given key for the given store, * or {@code null} if no matching metadata could be found. */ public KeyQueryMetadata queryMetadataForKey(final String storeName, final K key, final Serializer keySerializer) { validateIsRunningOrRebalancing(); return streamsMetadataState.getKeyQueryMetadataForKey(storeName, key, keySerializer); } /** * Finds the metadata containing the active hosts and standby hosts where the key being queried would reside. * * @param storeName the {@code storeName} to find metadata for * @param key the key to find metadata for * @param partitioner the partitioner to be use to locate the host for the key * @param key type * Returns {@link KeyQueryMetadata} containing all metadata about hosting the given key for the given store, using the * the supplied partitioner, or {@code null} if no matching metadata could be found. */ public KeyQueryMetadata queryMetadataForKey(final String storeName, final K key, final StreamPartitioner partitioner) { validateIsRunningOrRebalancing(); return streamsMetadataState.getKeyQueryMetadataForKey(storeName, key, partitioner); } /** * Get a facade wrapping the local {@link StateStore} instances with the provided {@link StoreQueryParameters}. * The returned object can be used to query the {@link StateStore} instances. * * @param storeQueryParameters the parameters used to fetch a queryable store * @return A facade wrapping the local {@link StateStore} instances * @throws StreamsNotStartedException If Streams has not yet been started. Just call {@link KafkaStreams#start()} * and then retry this call. * @throws UnknownStateStoreException If the specified store name does not exist in the topology. * @throws InvalidStateStorePartitionException If the specified partition does not exist. * @throws InvalidStateStoreException If the Streams instance isn't in a queryable state. * If the store's type does not match the QueryableStoreType, * the Streams instance is not in a queryable state with respect * to the parameters, or if the store is not available locally, then * an InvalidStateStoreException is thrown upon store access. */ public T store(final StoreQueryParameters storeQueryParameters) { validateIsRunningOrRebalancing(); final String storeName = storeQueryParameters.storeName(); if (!topologyMetadata.hasStore(storeName)) { throw new UnknownStateStoreException( "Cannot get state store " + storeName + " because no such store is registered in the topology." ); } return queryableStoreProvider.getStore(storeQueryParameters); } /** * This method pauses processing for the KafkaStreams instance. * *

Paused topologies will only skip over a) processing, b) punctuation, and c) standby tasks. * Notably, paused topologies will still poll Kafka consumers, and commit offsets. * This method sets transient state that is not maintained or managed among instances. * Note that pause() can be called before start() in order to start a KafkaStreams instance * in a manner where the processing is paused as described, but the consumers are started up. */ public void pause() { if (topologyMetadata.hasNamedTopologies()) { for (final NamedTopology namedTopology : topologyMetadata.getAllNamedTopologies()) { topologyMetadata.pauseTopology(namedTopology.name()); } } else { topologyMetadata.pauseTopology(UNNAMED_TOPOLOGY); } } /** * @return true when the KafkaStreams instance has its processing paused. */ public boolean isPaused() { if (topologyMetadata.hasNamedTopologies()) { return topologyMetadata.getAllNamedTopologies().stream() .map(NamedTopology::name) .allMatch(topologyMetadata::isPaused); } else { return topologyMetadata.isPaused(UNNAMED_TOPOLOGY); } } /** * This method resumes processing for the KafkaStreams instance. */ public void resume() { if (topologyMetadata.hasNamedTopologies()) { for (final NamedTopology namedTopology : topologyMetadata.getAllNamedTopologies()) { topologyMetadata.resumeTopology(namedTopology.name()); } } else { topologyMetadata.resumeTopology(UNNAMED_TOPOLOGY); } threads.forEach(StreamThread::signalResume); } /** * handle each stream thread in a snapshot of threads. * noted: iteration over SynchronizedList is not thread safe so it must be manually synchronized. However, we may * require other locks when looping threads and it could cause deadlock. Hence, we create a copy to avoid holding * threads lock when looping threads. * @param consumer handler */ protected int processStreamThread(final Consumer consumer) { final List copy = new ArrayList<>(threads); for (final StreamThread thread : copy) consumer.accept(thread); return copy.size(); } /** * Returns the internal clients' assigned {@code client instance ids}. *

* Note, if {@link StreamsConfig#PROCESSING_GUARANTEE_CONFIG} is set to {@link StreamsConfig#EXACTLY_ONCE}, * the producer client instance ids are not returned yet. This gap will be closed in the next release. * * @return The internal clients' assigned instance ids used for metrics collection. * * @throws IllegalArgumentException If {@code timeout} is negative. * @throws IllegalStateException If {@code KafkaStreams} is not running. * @throws TimeoutException Indicates that a request timed out. * @throws StreamsException For any other error that might occur. */ public synchronized ClientInstanceIds clientInstanceIds(final Duration timeout) { if (timeout.isNegative()) { throw new IllegalArgumentException("The timeout cannot be negative."); } if (state().hasNotStarted()) { throw new IllegalStateException("KafkaStreams has not been started, you can retry after calling start()."); } if (state().isShuttingDown() || state.hasCompletedShutdown()) { throw new IllegalStateException("KafkaStreams has been stopped (" + state + ")."); } final Timer remainingTime = time.timer(timeout.toMillis()); final ClientInstanceIdsImpl clientInstanceIds = new ClientInstanceIdsImpl(); // (1) fan-out calls to threads // StreamThread for main/restore consumers and producer(s) final Map> consumerFutures = new HashMap<>(); final Map>>> producerFutures = new HashMap<>(); synchronized (changeThreadCount) { for (final StreamThread streamThread : threads) { consumerFutures.putAll(streamThread.consumerClientInstanceIds(timeout)); producerFutures.put(streamThread.getName(), streamThread.producersClientInstanceIds(timeout)); } } // GlobalThread KafkaFuture globalThreadFuture = null; if (globalStreamThread != null) { globalThreadFuture = globalStreamThread.globalConsumerInstanceId(timeout); } // (2) get admin client instance id in a blocking fashion, while Stream/GlobalThreads work in parallel try { clientInstanceIds.setAdminInstanceId(adminClient.clientInstanceId(timeout)); remainingTime.update(time.milliseconds()); } catch (final IllegalStateException telemetryDisabledError) { // swallow log.debug("Telemetry is disabled on the admin client."); } catch (final TimeoutException timeoutException) { throw timeoutException; } catch (final Exception error) { throw new StreamsException("Could not retrieve admin client instance id.", error); } // (3) collect client instance ids from threads // (3a) collect consumers from StreamsThread for (final Map.Entry> consumerFuture : consumerFutures.entrySet()) { final Uuid instanceId = getOrThrowException( consumerFuture.getValue(), remainingTime.remainingMs(), () -> String.format( "Could not retrieve consumer instance id for %s.", consumerFuture.getKey() ) ); remainingTime.update(time.milliseconds()); // could be `null` if telemetry is disabled on the consumer itself if (instanceId != null) { clientInstanceIds.addConsumerInstanceId( consumerFuture.getKey(), instanceId ); } else { log.debug(String.format("Telemetry is disabled for %s.", consumerFuture.getKey())); } } // (3b) collect producers from StreamsThread for (final Map.Entry>>> threadProducerFuture : producerFutures.entrySet()) { final Map> streamThreadProducerFutures = getOrThrowException( threadProducerFuture.getValue(), remainingTime.remainingMs(), () -> String.format( "Could not retrieve producer instance id for %s.", threadProducerFuture.getKey() ) ); remainingTime.update(time.milliseconds()); for (final Map.Entry> producerFuture : streamThreadProducerFutures.entrySet()) { final Uuid instanceId = getOrThrowException( producerFuture.getValue(), remainingTime.remainingMs(), () -> String.format( "Could not retrieve producer instance id for %s.", producerFuture.getKey() ) ); remainingTime.update(time.milliseconds()); // could be `null` if telemetry is disabled on the producer itself if (instanceId != null) { clientInstanceIds.addProducerInstanceId( producerFuture.getKey(), instanceId ); } else { log.debug(String.format("Telemetry is disabled for %s.", producerFuture.getKey())); } } } // (3c) collect from GlobalThread if (globalThreadFuture != null) { final Uuid instanceId = getOrThrowException( globalThreadFuture, remainingTime.remainingMs(), () -> "Could not retrieve global consumer client instance id." ); remainingTime.update(time.milliseconds()); // could be `null` if telemetry is disabled on the client itself if (instanceId != null) { clientInstanceIds.addConsumerInstanceId( globalStreamThread.getName(), instanceId ); } else { log.debug("Telemetry is disabled for the global consumer."); } } return clientInstanceIds; } private T getOrThrowException( final KafkaFuture future, final long timeoutMs, final Supplier errorMessage) { final Throwable cause; try { return future.get(timeoutMs, TimeUnit.MILLISECONDS); } catch (final java.util.concurrent.TimeoutException timeout) { throw new TimeoutException(errorMessage.get(), timeout); } catch (final ExecutionException exception) { cause = exception.getCause(); if (cause instanceof TimeoutException) { throw (TimeoutException) cause; } } catch (final InterruptedException error) { cause = error; } throw new StreamsException(errorMessage.get(), cause); } /** * Returns runtime information about the local threads of this {@link KafkaStreams} instance. * * @return the set of {@link org.apache.kafka.streams.processor.ThreadMetadata}. * @deprecated since 3.0 use {@link #metadataForLocalThreads()} */ @Deprecated public Set localThreadsMetadata() { return metadataForLocalThreads().stream().map(threadMetadata -> new org.apache.kafka.streams.processor.ThreadMetadata( threadMetadata.threadName(), threadMetadata.threadState(), threadMetadata.consumerClientId(), threadMetadata.restoreConsumerClientId(), threadMetadata.producerClientIds(), threadMetadata.adminClientId(), threadMetadata.activeTasks().stream().map(taskMetadata -> new org.apache.kafka.streams.processor.TaskMetadata( taskMetadata.taskId().toString(), taskMetadata.topicPartitions(), taskMetadata.committedOffsets(), taskMetadata.endOffsets(), taskMetadata.timeCurrentIdlingStarted()) ).collect(Collectors.toSet()), threadMetadata.standbyTasks().stream().map(taskMetadata -> new org.apache.kafka.streams.processor.TaskMetadata( taskMetadata.taskId().toString(), taskMetadata.topicPartitions(), taskMetadata.committedOffsets(), taskMetadata.endOffsets(), taskMetadata.timeCurrentIdlingStarted()) ).collect(Collectors.toSet()))) .collect(Collectors.toSet()); } /** * Returns runtime information about the local threads of this {@link KafkaStreams} instance. * * @return the set of {@link ThreadMetadata}. */ public Set metadataForLocalThreads() { final Set threadMetadata = new HashSet<>(); processStreamThread(thread -> { synchronized (thread.getStateLock()) { if (thread.state() != StreamThread.State.DEAD) { threadMetadata.add(thread.threadMetadata()); } } }); return threadMetadata; } /** * Returns {@link LagInfo}, for all store partitions (active or standby) local to this Streams instance. Note that the * values returned are just estimates and meant to be used for making soft decisions on whether the data in the store * partition is fresh enough for querying. * *

Note: Each invocation of this method issues a call to the Kafka brokers. Thus, it's advisable to limit the frequency * of invocation to once every few seconds. * * @return map of store names to another map of partition to {@link LagInfo}s * @throws StreamsException if the admin client request throws exception */ public Map> allLocalStorePartitionLags() { final List allTasks = new ArrayList<>(); processStreamThread(thread -> allTasks.addAll(thread.readyOnlyAllTasks())); return allLocalStorePartitionLags(allTasks); } protected Map> allLocalStorePartitionLags(final List tasksToCollectLagFor) { final Map> localStorePartitionLags = new TreeMap<>(); final Collection allPartitions = new LinkedList<>(); final Map allChangelogPositions = new HashMap<>(); // Obtain the current positions, of all the active-restoring and standby tasks for (final Task task : tasksToCollectLagFor) { allPartitions.addAll(task.changelogPartitions()); // Note that not all changelog partitions, will have positions; since some may not have started allChangelogPositions.putAll(task.changelogOffsets()); } log.debug("Current changelog positions: {}", allChangelogPositions); final Map allEndOffsets; allEndOffsets = fetchEndOffsets(allPartitions, adminClient); log.debug("Current end offsets :{}", allEndOffsets); for (final Map.Entry entry : allEndOffsets.entrySet()) { // Avoiding an extra admin API lookup by computing lags for not-yet-started restorations // from zero instead of the real "earliest offset" for the changelog. // This will yield the correct relative order of lagginess for the tasks in the cluster, // but it is an over-estimate of how much work remains to restore the task from scratch. final long earliestOffset = 0L; final long changelogPosition = allChangelogPositions.getOrDefault(entry.getKey(), earliestOffset); final long latestOffset = entry.getValue().offset(); final LagInfo lagInfo = new LagInfo(changelogPosition == Task.LATEST_OFFSET ? latestOffset : changelogPosition, latestOffset); final String storeName = streamsMetadataState.getStoreForChangelogTopic(entry.getKey().topic()); localStorePartitionLags.computeIfAbsent(storeName, ignored -> new TreeMap<>()) .put(entry.getKey().partition(), lagInfo); } return Collections.unmodifiableMap(localStorePartitionLags); } /** * Run an interactive query against a state store. *

* This method allows callers outside of the Streams runtime to access the internal state of * stateful processors. See IQ docs * for more information. *

* NOTICE: This functionality is {@link Evolving} and subject to change in minor versions. * Once it is stabilized, this notice and the evolving annotation will be removed. * * @param The result type specified by the query. * @throws StreamsNotStartedException If Streams has not yet been started. Just call {@link * KafkaStreams#start()} and then retry this call. * @throws StreamsStoppedException If Streams is in a terminal state like PENDING_SHUTDOWN, * NOT_RUNNING, PENDING_ERROR, or ERROR. The caller should * discover a new instance to query. * @throws UnknownStateStoreException If the specified store name does not exist in the * topology. */ @Evolving public StateQueryResult query(final StateQueryRequest request) { final String storeName = request.getStoreName(); if (!topologyMetadata.hasStore(storeName)) { throw new UnknownStateStoreException( "Cannot get state store " + storeName + " because no such store is registered in the topology." ); } if (state().hasNotStarted()) { throw new StreamsNotStartedException( "KafkaStreams has not been started, you can retry after calling start()." ); } if (state().isShuttingDown() || state.hasCompletedShutdown()) { throw new StreamsStoppedException( "KafkaStreams has been stopped (" + state + ")." + " This instance can no longer serve queries." ); } final StateQueryResult result = new StateQueryResult<>(); final Map globalStateStores = topologyMetadata.globalStateStores(); if (globalStateStores.containsKey(storeName)) { // See KAFKA-13523 result.setGlobalResult( QueryResult.forFailure( FailureReason.UNKNOWN_QUERY_TYPE, "Global stores do not yet support the KafkaStreams#query API. Use KafkaStreams#store instead." ) ); } else { for (final StreamThread thread : threads) { final Set tasks = thread.readyOnlyAllTasks(); for (final Task task : tasks) { final TaskId taskId = task.id(); final int partition = taskId.partition(); if (request.isAllPartitions() || request.getPartitions().contains(partition)) { final StateStore store = task.getStore(storeName); if (store != null) { final StreamThread.State state = thread.state(); final boolean active = task.isActive(); if (request.isRequireActive() && (state != StreamThread.State.RUNNING || !active)) { result.addResult( partition, QueryResult.forFailure( FailureReason.NOT_ACTIVE, "Query requires a running active task," + " but partition was in state " + state + " and was " + (active ? "active" : "not active") + "." ) ); } else { final QueryResult r = store.query( request.getQuery(), request.isRequireActive() ? PositionBound.unbounded() : request.getPositionBound(), new QueryConfig(request.executionInfoEnabled()) ); result.addResult(partition, r); } // optimization: if we have handled all the requested partitions, // we can return right away. if (!request.isAllPartitions() && result.getPartitionResults().keySet().containsAll(request.getPartitions())) { return result; } } } } } } if (!request.isAllPartitions()) { for (final Integer partition : request.getPartitions()) { if (!result.getPartitionResults().containsKey(partition)) { result.addResult(partition, QueryResult.forFailure( FailureReason.NOT_PRESENT, "The requested partition was not present at the time of the query." )); } } } return result; } }





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