dianfu commented on a change in pull request #9653: [FLINK-14014][python] Introduce PythonScalarFunctionRunner to handle the communication with Python worker for Python ScalarFunction execution URL: https://github.com/apache/flink/pull/9653#discussion_r325030418
########## File path: flink-python/src/main/java/org/apache/flink/python/AbstractPythonFunctionRunner.java ########## @@ -0,0 +1,296 @@ +/* + * 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.python; + +import org.apache.flink.annotation.Internal; +import org.apache.flink.core.memory.ByteArrayInputStreamWithPos; +import org.apache.flink.core.memory.ByteArrayOutputStreamWithPos; +import org.apache.flink.table.functions.python.PythonEnv; +import org.apache.flink.util.Preconditions; + +import org.apache.beam.model.fnexecution.v1.BeamFnApi; +import org.apache.beam.model.pipeline.v1.RunnerApi; +import org.apache.beam.runners.core.construction.Environments; +import org.apache.beam.runners.core.construction.PipelineOptionsTranslation; +import org.apache.beam.runners.core.construction.graph.ExecutableStage; +import org.apache.beam.runners.fnexecution.control.BundleProgressHandler; +import org.apache.beam.runners.fnexecution.control.DefaultJobBundleFactory; +import org.apache.beam.runners.fnexecution.control.JobBundleFactory; +import org.apache.beam.runners.fnexecution.control.OutputReceiverFactory; +import org.apache.beam.runners.fnexecution.control.RemoteBundle; +import org.apache.beam.runners.fnexecution.control.StageBundleFactory; +import org.apache.beam.runners.fnexecution.provisioning.JobInfo; +import org.apache.beam.runners.fnexecution.state.StateRequestHandler; +import org.apache.beam.sdk.coders.Coder; +import org.apache.beam.sdk.fn.data.FnDataReceiver; +import org.apache.beam.sdk.options.PipelineOptionsFactory; +import org.apache.beam.sdk.options.PortablePipelineOptions; +import org.apache.beam.sdk.util.WindowedValue; +import org.apache.beam.vendor.grpc.v1p21p0.com.google.protobuf.Struct; + +import java.io.DataOutputStream; +import java.io.File; +import java.io.FileOutputStream; +import java.nio.file.Files; +import java.util.HashMap; +import java.util.Map; +import java.util.concurrent.CompletionStage; + +/** + * An base class for {@link PythonFunctionRunner}. + * + * @param <IN> Type of the input elements. + * @param <OUT> Type of the execution results. + */ +@Internal +public abstract class AbstractPythonFunctionRunner<IN, OUT> implements PythonFunctionRunner<IN> { + + private static final String MAIN_INPUT_ID = "input"; + + private final String taskName; + + /** + * The Python function execution result receiver. + */ + private final FnDataReceiver<OUT> resultReceiver; + + /** + * The Python execution environment. + */ + private final PythonEnv pythonEnv; + + /** + * The bundle factory which has all job-scoped information and can be used to create a {@link StageBundleFactory}. + */ + private transient JobBundleFactory jobBundleFactory; + + /** + * The bundle factory which has all of the resources it needs to provide new {@link RemoteBundle}. + */ + private transient StageBundleFactory stageBundleFactory; + + /** + * Handler for state requests. + */ + private final StateRequestHandler stateRequestHandler; + + /** + * Handler for bundle progress messages, both during bundle execution and on its completion. + */ + private transient BundleProgressHandler progressHandler; + + /** + * A bundle handler for handling input elements by forwarding them to a remote environment for processing. + * It holds a collection of {@link FnDataReceiver}s which actually perform the data forwarding work. + * + * <p>When a RemoteBundle is closed, it will block until bundle processing is finished on remote resources, + * and throw an exception if bundle processing has failed. + */ + private transient RemoteBundle remoteBundle; + + /** + * The receiver which forwards the input elements to a remote environment for processing. + */ + private transient FnDataReceiver<WindowedValue<?>> mainInputReceiver; + + /** + * The coder for input elements. + */ + private transient Coder<IN> inputCoder; + + /** + * The coder for execution results. + */ + private transient Coder<OUT> outputCoder; + + /** + * Reusable InputStream used to holding the execution results to be deserialized. + */ + private transient ByteArrayInputStreamWithPos bais; + + /** + * Reusable OutputStream used to holding the serialized input elements. + */ + private transient ByteArrayOutputStreamWithPos baos; + + public AbstractPythonFunctionRunner( + String taskName, + FnDataReceiver<OUT> resultReceiver, + PythonEnv pythonEnv, + StateRequestHandler stateRequestHandler) { + this.taskName = Preconditions.checkNotNull(taskName); + this.resultReceiver = Preconditions.checkNotNull(resultReceiver); + this.pythonEnv = Preconditions.checkNotNull(pythonEnv); + this.stateRequestHandler = Preconditions.checkNotNull(stateRequestHandler); + } + + @Override + public void open() throws Exception { + bais = new ByteArrayInputStreamWithPos(); + baos = new ByteArrayOutputStreamWithPos(); + inputCoder = getInputCoder(); + outputCoder = getOutputCoder(); + + PortablePipelineOptions portableOptions = + PipelineOptionsFactory.as(PortablePipelineOptions.class); + // one operator has one Python SDK harness + portableOptions.setSdkWorkerParallelism(1); + Struct pipelineOptions = PipelineOptionsTranslation.toProto(portableOptions); + + jobBundleFactory = createJobBundleFactory(pipelineOptions); + stageBundleFactory = jobBundleFactory.forStage(createExecutableStage()); + progressHandler = getProgressHandler(); + } + + @Override + public void close() throws Exception { + if (jobBundleFactory != null) { + jobBundleFactory.close(); + jobBundleFactory = null; + } + } + + @Override + public void startBundle() { + OutputReceiverFactory receiverFactory = + new OutputReceiverFactory() { + + // the input value type is always byte array + @SuppressWarnings("unchecked") + @Override + public FnDataReceiver<WindowedValue<byte[]>> create(String pCollectionId) { + return input -> { + bais.setBuffer(input.getValue(), 0, input.getValue().length); + resultReceiver.accept(outputCoder.decode(bais)); + }; + } + }; + + try { + remoteBundle = stageBundleFactory.getBundle(receiverFactory, stateRequestHandler, progressHandler); + mainInputReceiver = + Preconditions.checkNotNull( + remoteBundle.getInputReceivers().get(MAIN_INPUT_ID), + "Failed to retrieve main input receiver."); + } catch (Throwable t) { + throw new RuntimeException("Failed to start remote bundle", t); + } + } + + @Override + public void finishBundle() { + try { + remoteBundle.close(); + } catch (Throwable t) { + throw new RuntimeException("Failed to close remote bundle", t); + } + } + + @Override + public void processElement(IN element) { + try { + baos.reset(); + inputCoder.encode(element, baos); + // TODO: support to use ValueOnlyWindowedValueCoder for better performance. + // Currently, FullWindowedValueCoder has to be used in Beam's portability framework. + mainInputReceiver.accept(WindowedValue.valueInGlobalWindow(baos.toByteArray())); + } catch (Throwable t) { + throw new RuntimeException("Failed to process element when sending data to Python SDK harness.", t); + } + } + + public JobBundleFactory createJobBundleFactory(Struct pipelineOptions) throws Exception { + return DefaultJobBundleFactory.create( + JobInfo.create(taskName, taskName, createEmptyRetrievalToken(), pipelineOptions)); + } + + /** + * Creates a specification which specifies the portability Python execution environment. + * It's used by Beam's portability framework to creates the actual Python execution environment. + */ + protected RunnerApi.Environment createPythonExecutionEnvironment() { + if (pythonEnv.getExecType() == PythonEnv.ExecType.PROCESS) { + final Map<String, String> env = new HashMap<>(2); + env.put("python", pythonEnv.getPythonExec()); + env.put("pip", pythonEnv.getPipExec()); + + return Environments.createProcessEnvironment( + "", + "", + pythonEnv.getPythonWorkerCmd(), + env); + } else { + throw new UnsupportedOperationException(String.format( + "Execution type '%s' is not supported.", pythonEnv.getExecType())); + } + } + + /** + * Creates a {@link ExecutableStage} which contains the Python user-defined functions to be executed + * and all the other information needed to execute them, such as the execution environment, the input + * and output coder, etc. + */ + public abstract ExecutableStage createExecutableStage(); + + /** + * Returns the coder for input elements. + */ + public abstract Coder<IN> getInputCoder(); + + /** + * Returns the coder for execution results. + */ + public abstract Coder<OUT> getOutputCoder(); + + /** + * An {@link StateRequestHandler} implementation which does nothing. + */ + public static class NoOpStateRequestHandler implements StateRequestHandler { + + @Override + public CompletionStage<BeamFnApi.StateResponse.Builder> handle(BeamFnApi.StateRequest request) { + return null; Review comment: +1 to use StateRequestHandler.unsupported() ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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