rkhachatryan commented on a change in pull request #11403: [FLINK-16316][operators] Implement new StreamOperatorBase as a replacement for AbstractStreamOperator URL: https://github.com/apache/flink/pull/11403#discussion_r396365770
########## File path: flink-streaming-java/src/main/java/org/apache/flink/streaming/api/operators/StreamOperatorStateHandler.java ########## @@ -0,0 +1,434 @@ +/* + * 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.flink.streaming.api.operators; + +import org.apache.flink.annotation.PublicEvolving; +import org.apache.flink.annotation.VisibleForTesting; +import org.apache.flink.api.common.ExecutionConfig; +import org.apache.flink.api.common.state.KeyedStateStore; +import org.apache.flink.api.common.state.State; +import org.apache.flink.api.common.state.StateDescriptor; +import org.apache.flink.api.common.typeutils.TypeSerializer; +import org.apache.flink.core.fs.CloseableRegistry; +import org.apache.flink.core.memory.DataOutputViewStreamWrapper; +import org.apache.flink.runtime.checkpoint.CheckpointException; +import org.apache.flink.runtime.checkpoint.CheckpointFailureReason; +import org.apache.flink.runtime.checkpoint.CheckpointOptions; +import org.apache.flink.runtime.state.AbstractKeyedStateBackend; +import org.apache.flink.runtime.state.CheckpointStreamFactory; +import org.apache.flink.runtime.state.DefaultKeyedStateStore; +import org.apache.flink.runtime.state.KeyGroupRange; +import org.apache.flink.runtime.state.KeyGroupStatePartitionStreamProvider; +import org.apache.flink.runtime.state.KeyGroupsList; +import org.apache.flink.runtime.state.KeyedStateBackend; +import org.apache.flink.runtime.state.KeyedStateCheckpointOutputStream; +import org.apache.flink.runtime.state.OperatorStateBackend; +import org.apache.flink.runtime.state.StateInitializationContext; +import org.apache.flink.runtime.state.StateInitializationContextImpl; +import org.apache.flink.runtime.state.StatePartitionStreamProvider; +import org.apache.flink.runtime.state.StateSnapshotContext; +import org.apache.flink.runtime.state.StateSnapshotContextSynchronousImpl; +import org.apache.flink.runtime.state.VoidNamespaceSerializer; +import org.apache.flink.streaming.api.watermark.Watermark; +import org.apache.flink.util.CloseableIterable; +import org.apache.flink.util.ExceptionUtils; +import org.apache.flink.util.IOUtils; +import org.apache.flink.util.function.ThrowingConsumer; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import javax.annotation.Nullable; + +import java.io.Closeable; +import java.io.IOException; +import java.util.Optional; + +/** + * Class encapsulating various state backend handling logic for {@link StreamOperator} implementations. + */ +@PublicEvolving +public class StreamOperatorStateHandler { + + protected static final Logger LOG = LoggerFactory.getLogger(StreamOperatorStateHandler.class); + + /** Backend for keyed state. This might be empty if we're not on a keyed stream. */ + @Nullable + private final AbstractKeyedStateBackend<?> keyedStateBackend; + private final CloseableRegistry closeableRegistry; + @Nullable + private final DefaultKeyedStateStore keyedStateStore; + private final OperatorStateBackend operatorStateBackend; + private final InternalTimeServiceManager<?> timeServiceManager; + private final StreamOperatorStateContext context; + + public StreamOperatorStateHandler( + StreamOperatorStateContext context, + ExecutionConfig executionConfig, + CloseableRegistry closeableRegistry) { + this.context = context; + operatorStateBackend = context.operatorStateBackend(); + keyedStateBackend = context.keyedStateBackend(); + this.closeableRegistry = closeableRegistry; + + if (keyedStateBackend != null) { + keyedStateStore = new DefaultKeyedStateStore(keyedStateBackend, executionConfig); + } + else { + keyedStateStore = null; + } + + timeServiceManager = context.internalTimerServiceManager(); + } + + public void initializeOperatorState(ThrowingConsumer<StateInitializationContext, Exception> initializeOperatorAction) throws Exception { + CloseableIterable<KeyGroupStatePartitionStreamProvider> keyedStateInputs = context.rawKeyedStateInputs(); + CloseableIterable<StatePartitionStreamProvider> operatorStateInputs = context.rawOperatorStateInputs(); + + try { + StateInitializationContext initializationContext = new StateInitializationContextImpl( + context.isRestored(), // information whether we restore or start for the first time + operatorStateBackend, // access to operator state backend + keyedStateStore, // access to keyed state backend + keyedStateInputs, // access to keyed state stream + operatorStateInputs); // access to operator state stream + + initializeOperatorAction.accept(initializationContext); + } finally { + closeFromRegistry(operatorStateInputs, closeableRegistry); + closeFromRegistry(keyedStateInputs, closeableRegistry); + } + } + + private static void closeFromRegistry(Closeable closeable, CloseableRegistry registry) { + if (registry.unregisterCloseable(closeable)) { + IOUtils.closeQuietly(closeable); + } + } + + public void dispose() throws Exception { + + Exception exception = null; + + try { + if (closeableRegistry.unregisterCloseable(operatorStateBackend)) { + operatorStateBackend.close(); + } + } catch (Exception e) { + exception = e; + } + + try { + if (closeableRegistry.unregisterCloseable(keyedStateBackend)) { + keyedStateBackend.close(); + } + } catch (Exception e) { + exception = ExceptionUtils.firstOrSuppressed(e, exception); + } + + try { + if (operatorStateBackend != null) { + operatorStateBackend.dispose(); + } + } catch (Exception e) { + exception = ExceptionUtils.firstOrSuppressed(e, exception); + } + + try { + if (keyedStateBackend != null) { + keyedStateBackend.dispose(); + } + } catch (Exception e) { + exception = ExceptionUtils.firstOrSuppressed(e, exception); + } + + if (exception != null) { + throw exception; + } + } + + public OperatorSnapshotFutures snapshotState( + ThrowingConsumer<StateSnapshotContext, Exception> snapshotStateAction, + String operatorName, + long checkpointId, + long timestamp, + CheckpointOptions checkpointOptions, + CheckpointStreamFactory factory) throws CheckpointException { + KeyGroupRange keyGroupRange = null != keyedStateBackend ? + keyedStateBackend.getKeyGroupRange() : KeyGroupRange.EMPTY_KEY_GROUP_RANGE; + + OperatorSnapshotFutures snapshotInProgress = new OperatorSnapshotFutures(); + + StateSnapshotContextSynchronousImpl snapshotContext = new StateSnapshotContextSynchronousImpl( + checkpointId, + timestamp, + factory, + keyGroupRange, + closeableRegistry); + + return snapshotState( + snapshotStateAction, + operatorName, + checkpointId, + timestamp, + checkpointOptions, + factory, + snapshotInProgress, + snapshotContext); + } + + @VisibleForTesting + OperatorSnapshotFutures snapshotState( + ThrowingConsumer<StateSnapshotContext, Exception> snapshotStateAction, + String operatorName, + long checkpointId, + long timestamp, + CheckpointOptions checkpointOptions, + CheckpointStreamFactory factory, + OperatorSnapshotFutures snapshotInProgress, + StateSnapshotContextSynchronousImpl snapshotContext) throws CheckpointException { + try { + snapshotState(snapshotContext, operatorName); + snapshotStateAction.accept(snapshotContext); + + snapshotInProgress.setKeyedStateRawFuture(snapshotContext.getKeyedStateStreamFuture()); + snapshotInProgress.setOperatorStateRawFuture(snapshotContext.getOperatorStateStreamFuture()); + + if (null != operatorStateBackend) { + snapshotInProgress.setOperatorStateManagedFuture( + operatorStateBackend.snapshot(checkpointId, timestamp, factory, checkpointOptions)); + } + + if (null != keyedStateBackend) { + snapshotInProgress.setKeyedStateManagedFuture( + keyedStateBackend.snapshot(checkpointId, timestamp, factory, checkpointOptions)); + } + } catch (Exception snapshotException) { + try { + snapshotInProgress.cancel(); + } catch (Exception e) { + snapshotException.addSuppressed(e); + } + + String snapshotFailMessage = "Could not complete snapshot " + checkpointId + " for operator " + + operatorName + "."; + + try { + snapshotContext.closeExceptionally(); + } catch (IOException e) { + snapshotException.addSuppressed(e); + } + throw new CheckpointException(snapshotFailMessage, CheckpointFailureReason.CHECKPOINT_DECLINED, snapshotException); + } + + return snapshotInProgress; + } + + /** + * Stream operators with state, which want to participate in a snapshot need to override this hook method. + * + * @param context context that provides information and means required for taking a snapshot + * @param operatorName + */ + public void snapshotState(StateSnapshotContext context, String operatorName) throws Exception { + final KeyedStateBackend<?> keyedStateBackend = getKeyedStateBackend(); + //TODO all of this can be removed once heap-based timers are integrated with RocksDB incremental snapshots + if (keyedStateBackend instanceof AbstractKeyedStateBackend && + ((AbstractKeyedStateBackend<?>) keyedStateBackend).requiresLegacySynchronousTimerSnapshots()) { + + KeyedStateCheckpointOutputStream out; + + try { + out = context.getRawKeyedOperatorStateOutput(); + } catch (Exception exception) { + throw new Exception("Could not open raw keyed operator state stream for " + + operatorName + '.', exception); + } + + try { + KeyGroupsList allKeyGroups = out.getKeyGroupList(); + for (int keyGroupIdx : allKeyGroups) { + out.startNewKeyGroup(keyGroupIdx); + + timeServiceManager.snapshotStateForKeyGroup( + new DataOutputViewStreamWrapper(out), keyGroupIdx); + } + } catch (Exception exception) { + throw new Exception("Could not write timer service of " + operatorName + + " to checkpoint state stream.", exception); + } finally { + try { + out.close(); + } catch (Exception closeException) { + LOG.warn("Could not close raw keyed operator state stream for {}. This " + + "might have prevented deleting some state data.", operatorName, closeException); + } + } + } + } + + public void notifyCheckpointComplete(long checkpointId) throws Exception { + if (keyedStateBackend != null) { + keyedStateBackend.notifyCheckpointComplete(checkpointId); + } + } + + @SuppressWarnings("unchecked") + public <K> KeyedStateBackend<K> getKeyedStateBackend() { + return (KeyedStateBackend<K>) keyedStateBackend; + } Review comment: 1. sorry, I messed it up with the base operator class. But nevertheless, we shouldn't expose class internals without a need. Here, all the usages are inside the package, so it could be package-private. 2. At least, we could split `StreamOperatorStateHandler` (regarding reference to `overall comment`, please see my reply to it). In either case, why not to parameterize `AbstractStreamOperatorV2`, `StreamOperatorStateHandler` and it's `keyedStateBackend`; in `AbstractStreamOperator` we can still have a cast; and each time we migrate an operator to V2 we add a proper type parameter (or `Object`). ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
