org.apache.beam.runners.apex.ApexRunnerResult.java Source code

Introduction

Here is the source code for org.apache.beam.runners.apex.ApexRunnerResult.java

Source

/*
 * 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.apex;

import com.datatorrent.api.DAG;
import java.io.IOException;
import javax.annotation.Nullable;
import org.apache.apex.api.Launcher.AppHandle;
import org.apache.apex.api.Launcher.ShutdownMode;
import org.apache.beam.sdk.Pipeline;
import org.apache.beam.sdk.PipelineResult;
import org.apache.beam.sdk.metrics.MetricResults;
import org.joda.time.Duration;

/** Result of executing a {@link Pipeline} with Apex in embedded mode. */
public class ApexRunnerResult implements PipelineResult {
    private final DAG apexDAG;
    private final AppHandle apexApp;
    private State state = State.UNKNOWN;

    public ApexRunnerResult(DAG dag, AppHandle apexApp) {
        this.apexDAG = dag;
        this.apexApp = apexApp;
    }

    @Override
    public State getState() {
        return state;
    }

    @Override
    public State cancel() throws IOException {
        apexApp.shutdown(ShutdownMode.KILL);
        cleanupOnCancelOrFinish();
        state = State.CANCELLED;
        return state;
    }

    @Override
    @Nullable
    public State waitUntilFinish(@Nullable Duration duration) {
        long timeout = (duration == null || duration.getMillis() < 1) ? Long.MAX_VALUE
                : System.currentTimeMillis() + duration.getMillis();
        try {
            while (!apexApp.isFinished() && System.currentTimeMillis() < timeout) {
                if (ApexRunner.ASSERTION_ERROR.get() != null) {
                    throw ApexRunner.ASSERTION_ERROR.get();
                }
                Thread.sleep(500);
            }
            if (apexApp.isFinished()) {
                cleanupOnCancelOrFinish();
                return State.DONE;
            }
            return null;
        } catch (InterruptedException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public State waitUntilFinish() {
        return waitUntilFinish(null);
    }

    @Override
    public MetricResults metrics() {
        throw new UnsupportedOperationException();
    }

    /**
     * Return the DAG executed by the pipeline.
     *
     * @return DAG from translation.
     */
    public DAG getApexDAG() {
        return apexDAG;
    }

    /** Opportunity for a subclass to perform cleanup, such as removing temporary files. */
    protected void cleanupOnCancelOrFinish() {
    }
}