org.apache.falcon.workflow.OozieWorkflowBuilder.java Source code

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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.falcon.workflow;

import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.falcon.FalconException;
import org.apache.falcon.FalconRuntimException;
import org.apache.falcon.Tag;
import org.apache.falcon.entity.ClusterHelper;
import org.apache.falcon.entity.EntityUtil;
import org.apache.falcon.entity.ExternalId;
import org.apache.falcon.entity.store.ConfigurationStore;
import org.apache.falcon.entity.v0.Entity;
import org.apache.falcon.entity.v0.EntityType;
import org.apache.falcon.entity.v0.cluster.Cluster;
import org.apache.falcon.entity.v0.cluster.Property;
import org.apache.falcon.hadoop.HadoopClientFactory;
import org.apache.falcon.messaging.EntityInstanceMessage.ARG;
import org.apache.falcon.oozie.bundle.BUNDLEAPP;
import org.apache.falcon.oozie.bundle.COORDINATOR;
import org.apache.falcon.oozie.coordinator.COORDINATORAPP;
import org.apache.falcon.oozie.coordinator.ObjectFactory;
import org.apache.falcon.oozie.workflow.ACTION;
import org.apache.falcon.oozie.workflow.CREDENTIAL;
import org.apache.falcon.oozie.workflow.CREDENTIALS;
import org.apache.falcon.oozie.workflow.WORKFLOWAPP;
import org.apache.falcon.security.SecurityUtil;
import org.apache.falcon.service.FalconPathFilter;
import org.apache.falcon.service.SharedLibraryHostingService;
import org.apache.falcon.util.OozieUtils;
import org.apache.falcon.util.RuntimeProperties;
import org.apache.falcon.util.StartupProperties;
import org.apache.falcon.workflow.engine.OozieWorkflowEngine;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.permission.FsAction;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.oozie.client.OozieClient;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.StringWriter;
import java.util.Arrays;
import java.util.Date;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Properties;
import java.util.Set;

/**
 * Base workflow builder for falcon entities.
 * @param <T>
 */
public abstract class OozieWorkflowBuilder<T extends Entity> extends WorkflowBuilder<T> {

    private static final Logger LOG = LoggerFactory.getLogger(OozieWorkflowBuilder.class);
    protected static final ConfigurationStore CONFIG_STORE = ConfigurationStore.get();

    protected static final String NOMINAL_TIME_EL = "${coord:formatTime(coord:nominalTime(), 'yyyy-MM-dd-HH-mm')}";
    protected static final String ACTUAL_TIME_EL = "${coord:formatTime(coord:actualTime(), 'yyyy-MM-dd-HH-mm')}";

    protected static final Long DEFAULT_BROKER_MSG_TTL = 3 * 24 * 60L;
    protected static final String MR_QUEUE_NAME = "queueName";
    protected static final String MR_JOB_PRIORITY = "jobPriority";

    protected static final String HIVE_CREDENTIAL_NAME = "falconHiveAuth";

    public static final String METASTOREURIS = "hive.metastore.uris";
    public static final String METASTORE_KERBEROS_PRINCIPAL = "hive.metastore.kerberos.principal";
    public static final String METASTORE_USE_THRIFT_SASL = "hive.metastore.sasl.enabled";

    protected static final String IGNORE = "IGNORE";

    public static final Set<String> FALCON_ACTIONS = new HashSet<String>(
            Arrays.asList(new String[] { "recordsize", "succeeded-post-processing", "failed-post-processing", }));

    protected static final FalconPathFilter FALCON_JAR_FILTER = new FalconPathFilter() {
        @Override
        public boolean accept(Path path) {
            return path.getName().startsWith("falcon");
        }

        @Override
        public String getJarName(Path path) {
            String name = path.getName();
            if (name.endsWith(".jar")) {
                name = name.substring(0, name.indexOf(".jar"));
            }
            return name;
        }
    };

    protected final boolean isSecurityEnabled;

    protected OozieWorkflowBuilder(T entity) {
        super(entity);
        isSecurityEnabled = SecurityUtil.isSecurityEnabled();
    }

    protected Path getCoordPath(Path bundlePath, String coordName) {
        Tag tag = EntityUtil.getWorkflowNameTag(coordName, entity);
        return new Path(bundlePath, tag.name());
    }

    protected abstract Map<String, String> getEntityProperties();

    public boolean map(Cluster cluster, Path bundlePath) throws FalconException {
        BUNDLEAPP bundleApp = new BUNDLEAPP();
        bundleApp.setName(EntityUtil.getWorkflowName(entity).toString());
        // all the properties are set prior to bundle and coordinators creation

        List<COORDINATORAPP> coordinators = getCoordinators(cluster, bundlePath);
        if (coordinators.size() == 0) {
            return false;
        }

        for (COORDINATORAPP coordinatorapp : coordinators) {
            Path coordPath = getCoordPath(bundlePath, coordinatorapp.getName());
            String coordXmlName = marshal(cluster, coordinatorapp, coordPath,
                    EntityUtil.getWorkflowNameSuffix(coordinatorapp.getName(), entity));

            createLogsDir(cluster, coordPath); //create logs dir
            // copy falcon libs to the workflow dir
            copySharedLibs(cluster, coordinatorapp);

            // add the coordinator to the bundle
            COORDINATOR bundleCoord = new COORDINATOR();
            bundleCoord.setName(coordinatorapp.getName());
            bundleCoord.setAppPath(getStoragePath(coordPath) + "/" + coordXmlName);
            bundleApp.getCoordinator().add(bundleCoord);
        }

        marshal(cluster, bundleApp, bundlePath); // write the bundle
        return true;
    }

    private void addExtensionJars(FileSystem fs, Path path, WORKFLOWAPP wf) throws IOException {
        FileStatus[] libs = null;
        try {
            libs = fs.listStatus(path);
        } catch (FileNotFoundException ignore) {
            //Ok if the libext is not configured
        }

        if (libs == null) {
            return;
        }

        for (FileStatus lib : libs) {
            if (lib.isDir()) {
                continue;
            }

            for (Object obj : wf.getDecisionOrForkOrJoin()) {
                if (!(obj instanceof ACTION)) {
                    continue;
                }
                ACTION action = (ACTION) obj;
                List<String> files = null;
                if (action.getJava() != null) {
                    files = action.getJava().getFile();
                } else if (action.getPig() != null) {
                    files = action.getPig().getFile();
                } else if (action.getMapReduce() != null) {
                    files = action.getMapReduce().getFile();
                }
                if (files != null) {
                    files.add(lib.getPath().toString());
                }
            }
        }
    }

    protected void addLibExtensionsToWorkflow(Cluster cluster, WORKFLOWAPP wf, EntityType type, String lifecycle)
            throws IOException, FalconException {
        String libext = ClusterHelper.getLocation(cluster, "working") + "/libext";
        FileSystem fs = HadoopClientFactory.get().createFileSystem(ClusterHelper.getConfiguration(cluster));
        addExtensionJars(fs, new Path(libext), wf);
        addExtensionJars(fs, new Path(libext, type.name()), wf);
        if (StringUtils.isNotEmpty(lifecycle)) {
            addExtensionJars(fs, new Path(libext, type.name() + "/" + lifecycle), wf);
        }
    }

    private void copySharedLibs(Cluster cluster, COORDINATORAPP coordinatorapp) throws FalconException {
        try {
            String coordPath = coordinatorapp.getAction().getWorkflow().getAppPath().replace("${nameNode}", "");
            Path libPath = new Path(coordPath, "lib");
            SharedLibraryHostingService.pushLibsToHDFS(StartupProperties.get().getProperty("system.lib.location"),
                    libPath, cluster, FALCON_JAR_FILTER);
        } catch (IOException e) {
            throw new FalconException("Failed to copy shared libs on cluster " + cluster.getName(), e);
        }
    }

    public abstract List<COORDINATORAPP> getCoordinators(Cluster cluster, Path bundlePath) throws FalconException;

    protected org.apache.falcon.oozie.coordinator.CONFIGURATION getCoordConfig(Map<String, String> propMap) {
        org.apache.falcon.oozie.coordinator.CONFIGURATION conf = new org.apache.falcon.oozie.coordinator.CONFIGURATION();
        List<org.apache.falcon.oozie.coordinator.CONFIGURATION.Property> props = conf.getProperty();
        for (Entry<String, String> prop : propMap.entrySet()) {
            props.add(createCoordProperty(prop.getKey(), prop.getValue()));
        }
        return conf;
    }

    protected Map<String, String> createCoordDefaultConfiguration(Cluster cluster, Path coordPath,
            String coordName) {
        Map<String, String> props = new HashMap<String, String>();
        props.put(ARG.entityName.getPropName(), entity.getName());
        props.put(ARG.nominalTime.getPropName(), NOMINAL_TIME_EL);
        props.put(ARG.timeStamp.getPropName(), ACTUAL_TIME_EL);
        props.put("userBrokerUrl", ClusterHelper.getMessageBrokerUrl(cluster));
        props.put("userBrokerImplClass", ClusterHelper.getMessageBrokerImplClass(cluster));
        String falconBrokerUrl = StartupProperties.get().getProperty(ARG.brokerUrl.getPropName(),
                "tcp://localhost:61616?daemon=true");
        props.put(ARG.brokerUrl.getPropName(), falconBrokerUrl);
        String falconBrokerImplClass = StartupProperties.get().getProperty(ARG.brokerImplClass.getPropName(),
                ClusterHelper.DEFAULT_BROKER_IMPL_CLASS);
        props.put(ARG.brokerImplClass.getPropName(), falconBrokerImplClass);
        String jmsMessageTTL = StartupProperties.get().getProperty("broker.ttlInMins",
                DEFAULT_BROKER_MSG_TTL.toString());
        props.put(ARG.brokerTTL.getPropName(), jmsMessageTTL);
        props.put(ARG.entityType.getPropName(), entity.getEntityType().name());
        props.put("logDir", getStoragePath(new Path(coordPath, "../../logs")));
        props.put(OozieClient.EXTERNAL_ID, new ExternalId(entity.getName(),
                EntityUtil.getWorkflowNameTag(coordName, entity), "${coord:nominalTime()}").getId());
        props.put("workflowEngineUrl", ClusterHelper.getOozieUrl(cluster));
        try {
            if (EntityUtil.getLateProcess(entity) == null
                    || EntityUtil.getLateProcess(entity).getLateInputs() == null
                    || EntityUtil.getLateProcess(entity).getLateInputs().size() == 0) {
                props.put("shouldRecord", "false");
            } else {
                props.put("shouldRecord", "true");
            }
        } catch (FalconException e) {
            LOG.error("Unable to get Late Process for entity: {}", entity, e);
            throw new FalconRuntimException(e);
        }
        props.put("entityName", entity.getName());
        props.put("entityType", entity.getEntityType().name().toLowerCase());
        props.put(ARG.cluster.getPropName(), cluster.getName());
        if (cluster.getProperties() != null) {
            for (Property prop : cluster.getProperties().getProperties()) {
                props.put(prop.getName(), prop.getValue());
            }
        }

        props.put(MR_QUEUE_NAME, "default");
        props.put(MR_JOB_PRIORITY, "NORMAL");
        //props in entity override the set props.
        props.putAll(getEntityProperties());
        return props;
    }

    protected org.apache.falcon.oozie.coordinator.CONFIGURATION.Property createCoordProperty(String name,
            String value) {
        org.apache.falcon.oozie.coordinator.CONFIGURATION.Property prop = new org.apache.falcon.oozie.coordinator.CONFIGURATION.Property();
        prop.setName(name);
        prop.setValue(value);
        return prop;
    }

    protected void marshal(Cluster cluster, JAXBElement<?> jaxbElement, JAXBContext jaxbContext, Path outPath)
            throws FalconException {
        try {
            Marshaller marshaller = jaxbContext.createMarshaller();
            marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
            FileSystem fs = HadoopClientFactory.get().createFileSystem(outPath.toUri(),
                    ClusterHelper.getConfiguration(cluster));
            OutputStream out = fs.create(outPath);
            try {
                marshaller.marshal(jaxbElement, out);
            } finally {
                out.close();
            }
            if (LOG.isDebugEnabled()) {
                StringWriter writer = new StringWriter();
                marshaller.marshal(jaxbElement, writer);
                LOG.debug("Writing definition to {} on cluster {}", outPath, cluster.getName());
                LOG.debug(writer.getBuffer().toString());
            }

            LOG.info("Marshalled {} to {}", jaxbElement.getDeclaredType(), outPath);
        } catch (Exception e) {
            throw new FalconException("Unable to marshall app object", e);
        }
    }

    private void createLogsDir(Cluster cluster, Path coordPath) throws FalconException {
        try {
            FileSystem fs = HadoopClientFactory.get().createFileSystem(coordPath.toUri(),
                    ClusterHelper.getConfiguration(cluster));
            Path logsDir = new Path(coordPath, "../../logs");
            fs.mkdirs(logsDir);

            // logs are copied with in oozie as the user in Post Processing and hence 777 permissions
            FsPermission permission = new FsPermission(FsAction.ALL, FsAction.ALL, FsAction.ALL);
            fs.setPermission(logsDir, permission);
        } catch (Exception e) {
            throw new FalconException("Unable to create temp dir in " + coordPath, e);
        }
    }

    protected String marshal(Cluster cluster, COORDINATORAPP coord, Path outPath, String name)
            throws FalconException {
        name = (StringUtils.isEmpty(name) ? "coordinator" : name) + ".xml";
        marshal(cluster, new ObjectFactory().createCoordinatorApp(coord), OozieUtils.COORD_JAXB_CONTEXT,
                new Path(outPath, name));
        return name;
    }

    protected void marshal(Cluster cluster, BUNDLEAPP bundle, Path outPath) throws FalconException {
        marshal(cluster, new org.apache.falcon.oozie.bundle.ObjectFactory().createBundleApp(bundle),
                OozieUtils.BUNDLE_JAXB_CONTEXT, new Path(outPath, "bundle.xml"));
    }

    protected void marshal(Cluster cluster, WORKFLOWAPP workflow, Path outPath) throws FalconException {
        marshal(cluster, new org.apache.falcon.oozie.workflow.ObjectFactory().createWorkflowApp(workflow),
                OozieUtils.WORKFLOW_JAXB_CONTEXT, new Path(outPath, "workflow.xml"));
    }

    protected String getStoragePath(Path path) {
        if (path != null) {
            return getStoragePath(path.toString());
        }
        return null;
    }

    protected String getStoragePath(String path) {
        if (StringUtils.isNotEmpty(path)) {
            if (new Path(path).toUri().getScheme() == null) {
                path = "${nameNode}" + path;
            }
        }
        return path;
    }

    protected WORKFLOWAPP getWorkflowTemplate(String template) throws FalconException {
        InputStream resourceAsStream = null;
        try {
            resourceAsStream = OozieWorkflowBuilder.class.getResourceAsStream(template);
            Unmarshaller unmarshaller = OozieUtils.WORKFLOW_JAXB_CONTEXT.createUnmarshaller();
            @SuppressWarnings("unchecked")
            JAXBElement<WORKFLOWAPP> jaxbElement = (JAXBElement<WORKFLOWAPP>) unmarshaller
                    .unmarshal(resourceAsStream);
            return jaxbElement.getValue();
        } catch (JAXBException e) {
            throw new FalconException(e);
        } finally {
            IOUtils.closeQuietly(resourceAsStream);
        }
    }

    protected COORDINATORAPP getCoordinatorTemplate(String template) throws FalconException {
        InputStream resourceAsStream = null;
        try {
            resourceAsStream = OozieWorkflowBuilder.class.getResourceAsStream(template);
            Unmarshaller unmarshaller = OozieUtils.COORD_JAXB_CONTEXT.createUnmarshaller();
            @SuppressWarnings("unchecked")
            JAXBElement<COORDINATORAPP> jaxbElement = (JAXBElement<COORDINATORAPP>) unmarshaller
                    .unmarshal(resourceAsStream);
            return jaxbElement.getValue();
        } catch (JAXBException e) {
            throw new FalconException(e);
        } finally {
            IOUtils.closeQuietly(resourceAsStream);
        }
    }

    // creates hive-site.xml configuration in conf dir for the given cluster on the same cluster.
    protected void createHiveConfiguration(Cluster cluster, Path workflowPath, String prefix)
            throws FalconException {
        Configuration hiveConf = getHiveCredentialsAsConf(cluster);

        try {
            Configuration conf = ClusterHelper.getConfiguration(cluster);
            FileSystem fs = HadoopClientFactory.get().createFileSystem(conf);

            // create hive conf to stagingDir
            Path confPath = new Path(workflowPath + "/conf");

            persistHiveConfiguration(fs, confPath, hiveConf, prefix);
        } catch (IOException e) {
            throw new FalconException("Unable to create create hive site", e);
        }
    }

    protected void persistHiveConfiguration(FileSystem fs, Path confPath, Cluster cluster, String prefix)
            throws IOException {
        Configuration hiveConf = getHiveCredentialsAsConf(cluster);
        persistHiveConfiguration(fs, confPath, hiveConf, prefix);
    }

    private void persistHiveConfiguration(FileSystem fs, Path confPath, Configuration hiveConf, String prefix)
            throws IOException {
        OutputStream out = null;
        try {
            out = fs.create(new Path(confPath, prefix + "hive-site.xml"));
            hiveConf.writeXml(out);
        } finally {
            IOUtils.closeQuietly(out);
        }
    }

    private Configuration getHiveCredentialsAsConf(Cluster cluster) {
        Map<String, String> hiveCredentials = getHiveCredentials(cluster);

        Configuration hiveConf = new Configuration(false);
        for (Entry<String, String> entry : hiveCredentials.entrySet()) {
            hiveConf.set(entry.getKey(), entry.getValue());
        }

        return hiveConf;
    }

    private Map<String, String> getHiveCredentials(Cluster cluster) {
        Map<String, String> hiveCredentials = new HashMap<String, String>();

        String metaStoreUrl = ClusterHelper.getRegistryEndPoint(cluster);
        if (metaStoreUrl == null) {
            throw new IllegalStateException("Registry interface is not defined in cluster: " + cluster.getName());
        }

        hiveCredentials.put(METASTOREURIS, metaStoreUrl);
        hiveCredentials.put("hive.metastore.execute.setugi", "true");
        hiveCredentials.put("hcatNode", metaStoreUrl.replace("thrift", "hcat"));
        hiveCredentials.put("hcat.metastore.uri", metaStoreUrl);

        if (isSecurityEnabled) {
            String principal = ClusterHelper.getPropertyValue(cluster, SecurityUtil.HIVE_METASTORE_PRINCIPAL);
            hiveCredentials.put(METASTORE_KERBEROS_PRINCIPAL, principal);
            hiveCredentials.put(METASTORE_USE_THRIFT_SASL, "true");
            hiveCredentials.put("hcat.metastore.principal", principal);
        }

        return hiveCredentials;
    }

    /**
     * This is only necessary if table is involved and is secure mode.
     *
     * @param cluster        cluster entity
     * @param credentialName credential name
     * @return CREDENTIALS object
     */
    protected CREDENTIAL createHCatalogCredential(Cluster cluster, String credentialName) {
        final String metaStoreUrl = ClusterHelper.getRegistryEndPoint(cluster);

        CREDENTIAL credential = new CREDENTIAL();
        credential.setName(credentialName);
        credential.setType("hcat");

        credential.getProperty().add(createProperty("hcat.metastore.uri", metaStoreUrl));
        credential.getProperty().add(createProperty("hcat.metastore.principal",
                ClusterHelper.getPropertyValue(cluster, SecurityUtil.HIVE_METASTORE_PRINCIPAL)));

        return credential;
    }

    private CREDENTIAL.Property createProperty(String name, String value) {
        CREDENTIAL.Property property = new CREDENTIAL.Property();
        property.setName(name);
        property.setValue(value);
        return property;
    }

    /**
     * This is only necessary if table is involved and is secure mode.
     *
     * @param workflowApp workflow xml
     * @param cluster     cluster entity
     */
    protected void addHCatalogCredentials(WORKFLOWAPP workflowApp, Cluster cluster, String credentialName) {
        CREDENTIALS credentials = workflowApp.getCredentials();
        if (credentials == null) {
            credentials = new CREDENTIALS();
        }

        credentials.getCredential().add(createHCatalogCredential(cluster, credentialName));

        // add credential for workflow
        workflowApp.setCredentials(credentials);
    }

    /**
     * This is only necessary if table is involved and is secure mode.
     *
     * @param workflowApp workflow xml
     * @param cluster     cluster entity
     */
    protected void addHCatalogCredentials(WORKFLOWAPP workflowApp, Cluster cluster, String credentialName,
            Set<String> actions) {
        addHCatalogCredentials(workflowApp, cluster, credentialName);

        // add credential to each action
        for (Object object : workflowApp.getDecisionOrForkOrJoin()) {
            if (!(object instanceof ACTION)) {
                continue;
            }

            ACTION action = (ACTION) object;
            String actionName = action.getName();
            if (actions.contains(actionName)) {
                action.setCred(credentialName);
            }
        }
    }

    protected abstract boolean shouldSetupHiveConfiguration(Cluster cluster, T entity) throws FalconException;

    protected void decorateWithOozieRetries(ACTION action) {
        Properties props = RuntimeProperties.get();
        action.setRetryMax(props.getProperty("falcon.parentworkflow.retry.max", "3"));
        action.setRetryInterval(props.getProperty("falcon.parentworkflow.retry.interval.secs", "1"));
    }

    protected Properties createAppProperties(String clusterName, Path bundlePath, String user)
            throws FalconException {
        Cluster cluster = EntityUtil.getEntity(EntityType.CLUSTER, clusterName);
        Properties properties = new Properties();
        if (cluster.getProperties() != null) {
            addClusterProperties(properties, cluster.getProperties().getProperties());
        }
        properties.setProperty(OozieWorkflowEngine.NAME_NODE, ClusterHelper.getStorageUrl(cluster));
        properties.setProperty(OozieWorkflowEngine.JOB_TRACKER, ClusterHelper.getMREndPoint(cluster));
        properties.setProperty(OozieClient.BUNDLE_APP_PATH,
                "${" + OozieWorkflowEngine.NAME_NODE + "}" + bundlePath.toString());
        properties.setProperty("colo.name", cluster.getColo());

        properties.setProperty(OozieClient.USER_NAME, user);
        properties.setProperty(OozieClient.USE_SYSTEM_LIBPATH, "true");
        properties.setProperty("falcon.libpath", ClusterHelper.getLocation(cluster, "working") + "/lib");

        if (shouldSetupHiveConfiguration(cluster, entity)) {
            propagateHiveCredentials(cluster, properties);
        }

        LOG.info("Cluster: {}, PROPS: {}", cluster.getName(), properties);
        return properties;
    }

    private void addClusterProperties(Properties properties, List<Property> clusterProperties) {
        for (Property prop : clusterProperties) {
            properties.setProperty(prop.getName(), prop.getValue());
        }
    }

    /**
     * This method propagates hive credentials for coordinator to authenticate against hive
     * for data availability triggers.
     *
     * @param cluster cluster entity
     * @param properties property object
     */
    private void propagateHiveCredentials(Cluster cluster, Properties properties) {
        Map<String, String> hiveCredentials = getHiveCredentials(cluster);
        for (Entry<String, String> entry : hiveCredentials.entrySet()) {
            properties.setProperty(entry.getKey(), entry.getValue());
        }
    }

    public abstract Date getNextStartTime(T entity, String cluster, Date now) throws FalconException;
}