| /* |
| * 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.runners.dataflow.worker.graph; |
| |
| import com.google.api.services.dataflow.model.FlattenInstruction; |
| import com.google.api.services.dataflow.model.MapTask; |
| import java.util.function.Function; |
| import org.apache.beam.runners.dataflow.worker.graph.Edges.Edge; |
| import org.apache.beam.runners.dataflow.worker.graph.Nodes.Node; |
| import org.apache.beam.runners.dataflow.worker.graph.Nodes.ParallelInstructionNode; |
| import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Predicate; |
| import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.ImmutableList; |
| import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables; |
| import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.graph.MutableNetwork; |
| |
| /** |
| * A function which removes {@link FlattenInstruction}s from the network representation of a {@link |
| * MapTask}. Remove a Flatten instruction and its PCollection by directly connecting the predecessor |
| * PCollections of the Flatten with the successor instructions. |
| */ |
| public class RemoveFlattenInstructionsFunction |
| implements Function<MutableNetwork<Node, Edge>, MutableNetwork<Node, Edge>> { |
| |
| @Override |
| public MutableNetwork<Node, Edge> apply(MutableNetwork<Node, Edge> network) { |
| for (Node node : ImmutableList.copyOf(Iterables.filter(network.nodes(), IsFlatten.INSTANCE))) { |
| |
| // For each successor instruction after the Flatten, connect it directly to the |
| // predecessor PCollections of Flatten. |
| Node flattenPCollection = Iterables.getOnlyElement(network.successors(node)); |
| for (Node successorInstruction : |
| ImmutableList.copyOf(network.successors(flattenPCollection))) { |
| for (Edge edge : |
| ImmutableList.copyOf( |
| network.edgesConnecting(flattenPCollection, successorInstruction))) { |
| for (Node predecessorPCollection : ImmutableList.copyOf(network.predecessors(node))) { |
| network.addEdge(predecessorPCollection, successorInstruction, edge.clone()); |
| } |
| } |
| } |
| |
| // Remove the Flatten instruction and its output PCollection. |
| network.removeNode(flattenPCollection); |
| network.removeNode(node); |
| } |
| return network; |
| } |
| |
| /** |
| * A {@link Predicate} which returns true iff the {@link Node} represents a {@link |
| * ParallelInstructionNode} with a {@link FlattenInstruction}. |
| */ |
| private static class IsFlatten implements Predicate<Node> { |
| private static final IsFlatten INSTANCE = new IsFlatten(); |
| |
| @Override |
| public boolean apply(Node node) { |
| return node instanceof ParallelInstructionNode |
| && ((ParallelInstructionNode) node).getParallelInstruction().getFlatten() != null; |
| } |
| |
| // Hide visibility to prevent instantiation |
| private IsFlatten() {} |
| } |
| } |