| /* |
| * 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.beam.fn.harness.state; |
| |
| import java.io.IOException; |
| import org.apache.beam.model.fnexecution.v1.BeamFnApi.StateRequest; |
| import org.apache.beam.sdk.coders.Coder; |
| import org.apache.beam.sdk.fn.stream.DataStreams; |
| import org.apache.beam.sdk.transforms.Materializations.MultimapView; |
| import org.apache.beam.vendor.grpc.v1p13p1.com.google.protobuf.ByteString; |
| |
| /** |
| * An implementation of a multimap side input that utilizes the Beam Fn State API to fetch values. |
| * |
| * <p>TODO: Support block level caching and prefetch. |
| */ |
| public class MultimapSideInput<K, V> implements MultimapView<K, V> { |
| |
| private final BeamFnStateClient beamFnStateClient; |
| private final String instructionId; |
| private final String ptransformId; |
| private final String sideInputId; |
| private final ByteString encodedWindow; |
| private final Coder<K> keyCoder; |
| private final Coder<V> valueCoder; |
| |
| public MultimapSideInput( |
| BeamFnStateClient beamFnStateClient, |
| String instructionId, |
| String ptransformId, |
| String sideInputId, |
| ByteString encodedWindow, |
| Coder<K> keyCoder, |
| Coder<V> valueCoder) { |
| this.beamFnStateClient = beamFnStateClient; |
| this.instructionId = instructionId; |
| this.ptransformId = ptransformId; |
| this.sideInputId = sideInputId; |
| this.encodedWindow = encodedWindow; |
| this.keyCoder = keyCoder; |
| this.valueCoder = valueCoder; |
| } |
| |
| @Override |
| public Iterable<V> get(K k) { |
| ByteString.Output output = ByteString.newOutput(); |
| try { |
| keyCoder.encode(k, output); |
| } catch (IOException e) { |
| throw new IllegalStateException( |
| String.format("Failed to encode key %s for side input id %s.", k, sideInputId), e); |
| } |
| StateRequest.Builder requestBuilder = StateRequest.newBuilder(); |
| requestBuilder |
| .setInstructionReference(instructionId) |
| .getStateKeyBuilder() |
| .getMultimapSideInputBuilder() |
| .setPtransformId(ptransformId) |
| .setSideInputId(sideInputId) |
| .setWindow(encodedWindow) |
| .setKey(output.toByteString()); |
| |
| return new LazyCachingIteratorToIterable<>( |
| new DataStreams.DataStreamDecoder( |
| valueCoder, |
| DataStreams.inbound( |
| StateFetchingIterators.forFirstChunk(beamFnStateClient, requestBuilder.build())))); |
| } |
| } |