org.apache.airavata.gfac.impl.watcher.CancelRequestWatcherImpl.java Source code

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Here is the source code for org.apache.airavata.gfac.impl.watcher.CancelRequestWatcherImpl.java

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/*
 *
 * 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.airavata.gfac.impl.watcher;

import org.apache.airavata.common.utils.ZkConstants;
import org.apache.airavata.gfac.core.GFacException;
import org.apache.airavata.gfac.core.context.ProcessContext;
import org.apache.airavata.gfac.core.watcher.CancelRequestWatcher;
import org.apache.airavata.gfac.impl.Factory;
import org.apache.airavata.model.status.ExperimentState;
import org.apache.curator.framework.CuratorFramework;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class CancelRequestWatcherImpl implements CancelRequestWatcher {
    private static final Logger log = LoggerFactory.getLogger(CancelRequestWatcherImpl.class);
    private final String processId;
    private final String experimentId;
    private final int max_retry = 3;

    public CancelRequestWatcherImpl(String experimentId, String processId) {
        this.experimentId = experimentId;
        this.processId = processId;
    }

    @Override
    public void process(WatchedEvent watchedEvent) throws Exception {
        // this watcher change data in cancel listener node in the experiment node
        String path = watchedEvent.getPath();
        Watcher.Event.EventType type = watchedEvent.getType();
        CuratorFramework curatorClient = Factory.getCuratorClient();
        log.info("cancel watcher triggered process id {}.", processId);
        switch (type) {
        case NodeDataChanged:
            byte[] bytes = curatorClient.getData().forPath(path);
            String action = new String(bytes);
            if (action.equalsIgnoreCase(ZkConstants.ZOOKEEPER_CANCEL_REQEUST)) {
                cancelProcess(0);
            } else {
                curatorClient.getData().usingWatcher(this).forPath(path);
            }
            break;
        case NodeDeleted:
            //end of experiment execution, ignore this event
            log.info("expId: {}, cancel watcher trigger for process {} with event type {}", experimentId, processId,
                    type.name());
            break;
        case NodeCreated:
        case NodeChildrenChanged:
        case None:
            log.info("expId: {}, Cancel watcher trigger for process {} with event type {}", experimentId, processId,
                    type.name());
            if (path != null) {
                curatorClient.getData().usingWatcher(this).forPath(path);
            }
            break;
        default:
            log.info("expId: {}, Cancel watcher trigger for process {} with event type {}", experimentId, processId,
                    type.name());
            if (path != null) {
                curatorClient.getData().usingWatcher(this).forPath(path);
            }
            break;
        }
    }

    private void cancelProcess(int retryAttempt) throws GFacException {
        ProcessContext processContext = Factory.getGfacContext().getProcess(processId);
        if (processContext != null) {
            processContext.setCancel(true);
            log.info("expId {}, processId : {}, Cancelling process", experimentId, processId);
            Factory.getGFacEngine().cancelProcess(processContext);
        } else {
            if (retryAttempt < max_retry) {
                log.info("expId: {}, Cancel request came for processId {} but couldn't find process context. "
                        + "retry in {} s ", experimentId, processId, retryAttempt * 3);
                try {
                    Thread.sleep(retryAttempt++ * 3000);
                } catch (InterruptedException e) {
                    // ignore we don't care this exception.
                }
                cancelProcess(retryAttempt);
            } else {
                log.info("expId: {}, Cancel request came for processId {} but couldn't find process context.",
                        experimentId, processId);
            }
        }
    }
}