com.qwazr.scripts.ScriptManager.java Source code

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Here is the source code for com.qwazr.scripts.ScriptManager.java

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/**
 * Copyright 2014-2016 Emmanuel Keller / QWAZR
 * <p>
 * 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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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 com.qwazr.scripts;

import com.qwazr.cluster.manager.ClusterManager;
import com.qwazr.utils.LockUtils.ReadWriteLock;
import com.qwazr.utils.StringUtils;
import com.qwazr.utils.server.ServerException;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.ws.rs.core.Response.Status;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.net.URISyntaxException;
import java.util.*;
import java.util.concurrent.ExecutorService;

public class ScriptManager {

    public static final String SERVICE_NAME_SCRIPT = "scripts";

    private static final Logger logger = LoggerFactory.getLogger(ScriptManager.class);

    static ScriptManager INSTANCE = null;

    public synchronized static Class<? extends ScriptServiceInterface> load(ExecutorService executorService,
            File directory) throws IOException {
        if (INSTANCE != null)
            throw new IOException("Already loaded");
        try {
            INSTANCE = new ScriptManager(executorService, directory);
            return ClusterManager.INSTANCE.isCluster() ? ScriptClusterServiceImpl.class
                    : ScriptSingleServiceImpl.class;
        } catch (URISyntaxException e) {
            throw new IOException(e);
        }
    }

    public static ScriptManager getInstance() {
        if (INSTANCE == null)
            throw new RuntimeException("The scripts service is not enabled");
        return INSTANCE;
    }

    private final ScriptEngine scriptEngine;

    private final ReadWriteLock runsMapLock = new ReadWriteLock();
    private final HashMap<String, RunThreadAbstract> runsMap;

    final ExecutorService executorService;

    private ScriptManager(ExecutorService executorService, File rootDirectory)
            throws IOException, URISyntaxException {

        // Load Nashorn
        ScriptEngineManager manager = new ScriptEngineManager();
        scriptEngine = manager.getEngineByName("nashorn");
        runsMap = new HashMap<String, RunThreadAbstract>();
        this.executorService = executorService;
    }

    private File getScriptFile(String scriptPath) throws ServerException {
        if (StringUtils.isEmpty(scriptPath))
            throw new ServerException(Status.NOT_ACCEPTABLE, "No path given");
        final File scriptFile = new File(scriptPath);
        if (!scriptFile.exists())
            throw new ServerException(Status.NOT_FOUND, "Script not found: " + scriptPath);
        if (!scriptFile.isFile())
            throw new ServerException(Status.NOT_ACCEPTABLE, "Script is not a file: " + scriptPath);
        return scriptFile;
    }

    public String getScript(String scriptPath) throws IOException, ServerException {
        File scriptFile = getScriptFile(scriptPath);
        FileReader fileReader = new FileReader(scriptFile);
        try {
            return IOUtils.toString(fileReader);
        } finally {
            IOUtils.closeQuietly(fileReader);
        }
    }

    private RunThreadAbstract getNewScriptRunThread(String scriptPath, Map<String, ?> objects)
            throws ServerException, IOException, ClassNotFoundException {
        final RunThreadAbstract scriptRunThread;
        if (scriptPath.endsWith(".js"))
            scriptRunThread = new JsRunThread(scriptEngine, getScriptFile(scriptPath), objects);
        else
            scriptRunThread = new JavaRunThread(scriptPath, objects);
        addScriptRunThread(scriptPath, scriptRunThread);
        return scriptRunThread;
    }

    public RunThreadAbstract runSync(String scriptPath, Map<String, ?> objects)
            throws ServerException, IOException, ClassNotFoundException {
        if (logger.isInfoEnabled())
            logger.info("Run sync: " + scriptPath);
        RunThreadAbstract scriptRunThread = getNewScriptRunThread(scriptPath, objects);
        scriptRunThread.run();
        expireScriptRunThread();
        return scriptRunThread;
    }

    public ScriptRunStatus runAsync(String scriptPath, Map<String, ?> objects)
            throws ServerException, IOException, ClassNotFoundException {
        if (logger.isInfoEnabled())
            logger.info("Run async: " + scriptPath);
        RunThreadAbstract scriptRunThread = getNewScriptRunThread(scriptPath, objects);
        executorService.execute(scriptRunThread);
        expireScriptRunThread();
        return scriptRunThread.getStatus();
    }

    private void addScriptRunThread(String scriptPath, RunThreadAbstract scriptRunThread) {
        if (scriptRunThread == null)
            return;
        runsMapLock.w.lock();
        try {
            runsMap.put(scriptRunThread.getUUID(), scriptRunThread);
        } finally {
            runsMapLock.w.unlock();
        }
    }

    private void expireScriptRunThread() {
        runsMapLock.w.lock();
        try {
            List<String> uuidsToDelete = new ArrayList<String>();
            long currentTime = System.currentTimeMillis();
            for (RunThreadAbstract scriptRunThread : runsMap.values())
                if (scriptRunThread.hasExpired(currentTime))
                    uuidsToDelete.add(scriptRunThread.getUUID());
            for (String uuid : uuidsToDelete)
                runsMap.remove(uuid);
            if (logger.isInfoEnabled())
                logger.info("Expire " + uuidsToDelete.size() + " jobs");
        } finally {
            runsMapLock.w.unlock();
        }
    }

    Map<String, ScriptRunStatus> getRunsStatus() {
        runsMapLock.r.lock();
        try {
            LinkedHashMap<String, ScriptRunStatus> runStatusMap = new LinkedHashMap<String, ScriptRunStatus>();
            for (Map.Entry<String, RunThreadAbstract> entry : runsMap.entrySet())
                runStatusMap.put(entry.getKey(), entry.getValue().getStatus());
            return runStatusMap;
        } finally {
            runsMapLock.r.unlock();
        }
    }

    RunThreadAbstract getRunThread(String uuid) {
        runsMapLock.r.lock();
        try {
            return runsMap.get(uuid);
        } finally {
            runsMapLock.r.unlock();
        }
    }

}