tzulitai commented on a change in pull request #17: [FLINK-15954] Add a PersistedTable to the SDK URL: https://github.com/apache/flink-statefun/pull/17#discussion_r376680658
########## File path: statefun-flink/statefun-flink-core/src/main/java/org/apache/flink/statefun/flink/core/state/MultiplexedTableStateAccessor.java ########## @@ -0,0 +1,141 @@ +/* + * 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.statefun.flink.core.state; + +import com.google.protobuf.ByteString; +import java.io.IOException; +import java.util.Objects; +import javax.annotation.Nonnull; +import javax.annotation.Nullable; +import org.apache.flink.api.common.state.MapState; +import org.apache.flink.api.common.typeutils.TypeSerializer; +import org.apache.flink.core.memory.DataInputDeserializer; +import org.apache.flink.core.memory.DataOutputSerializer; +import org.apache.flink.statefun.flink.core.cache.SingleThreadedLruCache; +import org.apache.flink.statefun.flink.core.generated.MultiplexedStateKey; +import org.apache.flink.statefun.sdk.state.TableAccessor; + +final class MultiplexedTableStateAccessor<K, V> implements TableAccessor<K, V> { + private final MapState<MultiplexedStateKey, byte[]> mapStateHandle; + private final MultiplexedStateKey accessorMapKeyPrefix; + private final TaggedRawSerializer<K> keySerializer; + private final TaggedRawSerializer<V> valueSerializer; + + private final SingleThreadedLruCache<K, MultiplexedStateKey> commonKeysCache = + new SingleThreadedLruCache<>(128); + + MultiplexedTableStateAccessor( + MapState<MultiplexedStateKey, byte[]> handle, + MultiplexedStateKey accessorMapKeyPrefix, + TypeSerializer<K> subKeySerializer, + TypeSerializer<V> subValueSerializer) { + this.mapStateHandle = Objects.requireNonNull(handle); + this.keySerializer = new TaggedRawSerializer<>(new byte[0], subKeySerializer); + this.valueSerializer = new TaggedRawSerializer<>(new byte[0], subValueSerializer); + this.accessorMapKeyPrefix = accessorMapKeyPrefix; + } + + @Override + public void set(K key, V value) { + try { + MultiplexedStateKey keyBytes = stateKey(key); + if (value == null) { + mapStateHandle.remove(keyBytes); + } else { + byte[] bytes = valueSerializer.serialize(value); + mapStateHandle.put(keyBytes, bytes); + } + } catch (Exception e) { + throw new RuntimeException(e); + } + } + + @Override + public V get(K userKey) { + try { + final MultiplexedStateKey stateKey = stateKey(userKey); + final byte[] bytes = mapStateHandle.get(stateKey); + if (bytes == null) { + return null; + } + return valueSerializer.deserialize(bytes); + } catch (Exception e) { + throw new RuntimeException(e); + } + } + + @Override + public void remove(K userKey) { + try { + mapStateHandle.remove(stateKey(userKey)); + } catch (Exception e) { + throw new RuntimeException(e); + } + } + + @Nonnull + private MultiplexedStateKey stateKey(final K userKey) { + Objects.requireNonNull(userKey, "Key can not be NULL"); + @Nullable MultiplexedStateKey stateKey = commonKeysCache.get(userKey); + if (stateKey != null) { + return stateKey; + } + try { + commonKeysCache.put(userKey, stateKey = computeStateKeyFromUserKey(userKey)); + return stateKey; + } catch (IOException e) { + throw new RuntimeException("Unable to serialize the key " + userKey, e); + } + } + + private MultiplexedStateKey computeStateKeyFromUserKey(K userKey) throws IOException { + byte[] userKeyBytes = keySerializer.serialize(userKey); + ByteString userKeyByteString = ByteString.copyFrom(userKeyBytes); + return accessorMapKeyPrefix.toBuilder().addUserKeys(userKeyByteString).build(); + } + + private static final class TaggedRawSerializer<T> { + + private final TypeSerializer<T> delegate; + private final DataOutputSerializer output; + private final DataInputDeserializer input; + private final byte[] tag; + + TaggedRawSerializer(byte[] tag, TypeSerializer<T> delegate) { + this.tag = Objects.requireNonNull(tag); Review comment: I don't think we need this tag. It's also always an empty byte array being passed as argument in its usages. ---------------------------------------------------------------- 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
