| /* |
| * 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.wayang.flink.operators; |
| |
| import org.apache.flink.api.java.DataSet; |
| import org.apache.flink.api.java.utils.DataSetUtils; |
| import org.apache.wayang.basic.operators.SampleOperator; |
| import org.apache.wayang.core.api.exception.WayangException; |
| import org.apache.wayang.core.optimizer.OptimizationContext; |
| import org.apache.wayang.core.plan.wayangplan.ExecutionOperator; |
| import org.apache.wayang.core.platform.ChannelDescriptor; |
| import org.apache.wayang.core.platform.ChannelInstance; |
| import org.apache.wayang.core.platform.lineage.ExecutionLineageNode; |
| import org.apache.wayang.core.types.DataSetType; |
| import org.apache.wayang.core.util.Tuple; |
| import org.apache.wayang.flink.channels.DataSetChannel; |
| import org.apache.wayang.flink.execution.FlinkExecutor; |
| |
| import java.util.Arrays; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Random; |
| import java.util.function.IntUnaryOperator; |
| import java.util.function.LongUnaryOperator; |
| |
| /** |
| * Flink implementation of the {@link SampleOperator}. Sampling with replacement (i.e., the sample may contain duplicates) |
| */ |
| public class FlinkSampleOperator<Type> |
| extends SampleOperator<Type> |
| implements FlinkExecutionOperator { |
| private Random rand; |
| |
| |
| /** |
| * Creates a new instance. |
| */ |
| public FlinkSampleOperator(IntUnaryOperator sampleSizeFunction, DataSetType<Type> type, LongUnaryOperator seedFunction) { |
| super(sampleSizeFunction, type, Methods.RANDOM, seedFunction); |
| } |
| |
| /** |
| * Copies an instance (exclusive of broadcasts). |
| * |
| * @param that that should be copied |
| */ |
| public FlinkSampleOperator(SampleOperator<Type> that) { |
| super(that); |
| assert that.getSampleMethod() == Methods.RANDOM |
| || that.getSampleMethod() == Methods.BERNOULLI |
| || that.getSampleMethod() == Methods.RESERVOIR |
| || that.getSampleMethod() == Methods.ANY; |
| } |
| |
| @Override |
| public Tuple<Collection<ExecutionLineageNode>, Collection<ChannelInstance>> evaluate( |
| ChannelInstance[] inputs, |
| ChannelInstance[] outputs, |
| FlinkExecutor flinkExecutor, |
| OptimizationContext.OperatorContext operatorContext) { |
| assert inputs.length == this.getNumInputs(); |
| assert outputs.length == this.getNumOutputs(); |
| |
| final DataSetChannel.Instance input = (DataSetChannel.Instance) inputs[0]; |
| final DataSetChannel.Instance output = (DataSetChannel.Instance) outputs[0]; |
| |
| final DataSet<Type> dataSetInput = input.provideDataSet(); |
| |
| |
| long size = Long.MAX_VALUE; |
| /* try { |
| size = dataSetInput.count(); |
| } catch (Exception e) { |
| throw new WayangException(e); |
| }*/ |
| DataSet<Type> dataSetOutput; |
| |
| int sampleSize = this.getSampleSize(operatorContext); |
| long seed = this.getSeed(operatorContext); |
| |
| if(this.getSampleSize(operatorContext) >= size){ |
| dataSetOutput = dataSetInput; |
| }else { |
| double faction = (size / sampleSize) + 0.01d; |
| switch (this.getSampleMethod()) { |
| case RANDOM: |
| dataSetOutput = DataSetUtils.sampleWithSize(dataSetInput, true, sampleSize, seed); |
| break; |
| case ANY: |
| Random rand = new Random(seed); |
| dataSetOutput = dataSetInput.filter(a -> {return rand.nextBoolean();}).first(sampleSize); |
| break; |
| case BERNOULLI: |
| dataSetOutput = DataSetUtils.sample(dataSetInput, false, faction, seed).first(sampleSize); |
| break; |
| case RESERVOIR: |
| dataSetOutput = DataSetUtils.sampleWithSize(dataSetInput, true, sampleSize, seed); |
| break; |
| default: |
| throw new WayangException("The option is not valid"); |
| } |
| } |
| |
| // assuming the sample is small better use a collection instance, the optimizer can transform the output if necessary |
| output.accept(dataSetOutput, flinkExecutor); |
| |
| return ExecutionOperator.modelLazyExecution(inputs, outputs, operatorContext); |
| } |
| |
| @Override |
| protected ExecutionOperator createCopy() { |
| return new FlinkSampleOperator<Type>(this); |
| } |
| |
| @Override |
| public List<ChannelDescriptor> getSupportedInputChannels(int index) { |
| return Arrays.asList(DataSetChannel.DESCRIPTOR, DataSetChannel.DESCRIPTOR_MANY); |
| } |
| |
| @Override |
| public List<ChannelDescriptor> getSupportedOutputChannels(int index) { |
| assert index <= this.getNumOutputs() || (index == 0 && this.getNumOutputs() == 0); |
| return Collections.singletonList(DataSetChannel.DESCRIPTOR); |
| } |
| |
| public String getLoadProfileEstimatorConfigurationKey() { |
| return "wayang.flink.sample.load"; |
| } |
| |
| |
| @Override |
| public boolean containsAction() { |
| return true; |
| } |
| |
| |
| } |