co.cask.cdap.internal.app.runtime.distributed.AbstractTwillProgramController.java Source code

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Here is the source code for co.cask.cdap.internal.app.runtime.distributed.AbstractTwillProgramController.java

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/*
 * Copyright  2014-2016 Cask Data, Inc.
 *
 * Licensed 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 co.cask.cdap.internal.app.runtime.distributed;

import co.cask.cdap.app.runtime.LogLevelUpdater;
import co.cask.cdap.app.runtime.ProgramController;
import co.cask.cdap.internal.app.runtime.AbstractProgramController;
import co.cask.cdap.proto.id.ProgramId;
import co.cask.cdap.proto.id.ProgramRunId;
import com.google.common.util.concurrent.Futures;
import org.apache.hadoop.yarn.api.records.FinalApplicationStatus;
import org.apache.twill.api.RunId;
import org.apache.twill.api.TwillController;
import org.apache.twill.api.logging.LogEntry;
import org.apache.twill.common.Threads;
import org.apache.twill.yarn.YarnTwillController;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.Map;
import java.util.Set;
import javax.annotation.Nullable;

/**
 * A {@link ProgramController} that control program through twill.
 */
public abstract class AbstractTwillProgramController extends AbstractProgramController
        implements ProgramController, LogLevelUpdater {

    private static final Logger LOG = LoggerFactory.getLogger(AbstractTwillProgramController.class);

    private final TwillController twillController;
    private volatile boolean stopRequested;

    protected AbstractTwillProgramController(ProgramId programId, TwillController twillController, RunId runId) {
        super(programId, runId);
        this.twillController = twillController;
    }

    /**
     * Get the RunId associated with the Twill controller.
     * @return the Twill RunId
     */
    public RunId getTwillRunId() {
        return twillController.getRunId();
    }

    /**
     * Starts listening to TwillController state changes. For internal use only.
     * The listener cannot be binded in constructor to avoid reference leak.
     *
     * @return this instance.
     */
    public ProgramController startListen() {
        twillController.onRunning(new Runnable() {
            @Override
            public void run() {
                LOG.info("Twill program running: {}, twill runId: {}", getProgramRunId(),
                        twillController.getRunId());
                started();
            }
        }, Threads.SAME_THREAD_EXECUTOR);

        twillController.onTerminated(new Runnable() {
            @Override
            public void run() {
                LOG.info("Twill program terminated: {}, twill runId: {}", getProgramRunId(),
                        twillController.getRunId());
                if (stopRequested) {
                    // Service was killed
                    stop();
                } else {
                    try {
                        // This never blocks since the twill controller is already terminated. It will throw exception if
                        // the twill program failed.
                        twillController.awaitTerminated();
                        // Service completed by itself. Simply signal the state change of this controller.
                        // TODO (CDAP-6806): this should not be done with reflection but through a proper Twill API
                        // Figure out whether the final Yarn status is in error, if so, set state accordingly
                        if (twillController instanceof YarnTwillController) {
                            FinalApplicationStatus finalStatus = ((YarnTwillController) twillController)
                                    .getTerminationStatus();
                            if (FinalApplicationStatus.FAILED.equals(finalStatus)) {
                                complete(State.ERROR);
                                return;
                            } else if (FinalApplicationStatus.KILLED.equals(finalStatus)) {
                                complete(State.KILLED);
                                return;
                            }
                        }
                        // normal termination
                        complete();
                    } catch (Exception e) {
                        error(e);
                    }
                }
            }
        }, Threads.SAME_THREAD_EXECUTOR);
        return this;
    }

    @Override
    public void updateLogLevels(Map<String, LogEntry.Level> logLevels, @Nullable String componentName)
            throws Exception {
        if (componentName == null) {
            twillController.updateLogLevels(logLevels).get();
        } else {
            twillController.updateLogLevels(componentName, logLevels).get();
        }
    }

    @Override
    public void resetLogLevels(Set<String> loggerNames, @Nullable String componentName) throws Exception {
        if (componentName == null) {
            twillController.resetLogLevels(loggerNames.toArray(new String[loggerNames.size()])).get();
        } else {
            twillController
                    .resetRunnableLogLevels(componentName, loggerNames.toArray(new String[loggerNames.size()]))
                    .get();
        }
    }

    @Override
    protected final void doSuspend() throws Exception {
        twillController.sendCommand(ProgramCommands.SUSPEND).get();
    }

    @Override
    protected final void doResume() throws Exception {
        twillController.sendCommand(ProgramCommands.RESUME).get();
    }

    @Override
    protected final void doStop() throws Exception {
        stopRequested = true;
        Futures.getUnchecked(twillController.terminate());
    }

    protected final TwillController getTwillController() {
        return twillController;
    }
}