Fanoid commented on code in PR #210: URL: https://github.com/apache/flink-ml/pull/210#discussion_r1128873310
########## flink-ml-core/src/main/java/org/apache/flink/ml/common/sharedstorage/SharedStorageContextImpl.java: ########## @@ -0,0 +1,117 @@ +/* + * 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.ml.common.sharedstorage; + +import org.apache.flink.runtime.state.StateInitializationContext; +import org.apache.flink.runtime.state.StateSnapshotContext; +import org.apache.flink.streaming.api.operators.AbstractStreamOperator; +import org.apache.flink.streaming.api.operators.StreamingRuntimeContext; +import org.apache.flink.util.Preconditions; +import org.apache.flink.util.function.BiConsumerWithException; + +import java.io.Serializable; +import java.util.HashMap; +import java.util.Map; + +/** Default implementation of {@link SharedStorageContext} using {@link SharedStorage}. */ +@SuppressWarnings("rawtypes") +class SharedStorageContextImpl implements SharedStorageContext, Serializable { + private final StorageID storageID; + private final Map<ItemDescriptor, SharedStorage.Writer> writers = new HashMap<>(); + private final Map<ItemDescriptor, SharedStorage.Reader> readers = new HashMap<>(); + private Map<ItemDescriptor<?>, String> ownerMap; + + public SharedStorageContextImpl() { + this.storageID = new StorageID(); + } + + public void setOwnerMap(Map<ItemDescriptor<?>, String> ownerMap) { + this.ownerMap = ownerMap; + } + + @Override + public void invoke(BiConsumerWithException<SharedItemGetter, SharedItemSetter, Exception> func) + throws Exception { + func.accept(this::getSharedItem, this::setSharedItem); + } + + private <T> T getSharedItem(ItemDescriptor<T> key) { + //noinspection unchecked + SharedStorage.Reader<T> reader = readers.get(key); + Preconditions.checkState( + null != reader, + String.format( + "The operator requested to read a shared item %s not owned by itself.", + key)); + return reader.get(); + } + + private <T> void setSharedItem(ItemDescriptor<T> key, T value) { + //noinspection unchecked + SharedStorage.Writer<T> writer = writers.get(key); + Preconditions.checkState( + null != writer, + String.format( + "The operator requested to read a shared item %s not owned by itself.", + key)); + writer.set(value); + } + + @Override + public <T extends AbstractStreamOperator<?> & SharedStorageStreamOperator> void initializeState( + T operator, + StreamingRuntimeContext runtimeContext, + StateInitializationContext context) { + String ownerId = operator.getSharedStorageAccessorID(); + int subtaskId = runtimeContext.getIndexOfThisSubtask(); + for (Map.Entry<ItemDescriptor<?>, String> entry : ownerMap.entrySet()) { + ItemDescriptor descriptor = entry.getKey(); + if (ownerId.equals(entry.getValue())) { + writers.put( Review Comment: There is no instances to be overwritten here, because every subtask owns a distinct instance of `SharedStorageContextImpl`. The field of `context` in operators are serialized and then deserialized to different instances when operators being deployed. It just like other fields. -- 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. To unsubscribe, e-mail: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
