vault.queryrouter.models.dao.JobQueueDAO.java Source code

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Here is the source code for vault.queryrouter.models.dao.JobQueueDAO.java

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/*
* 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 vault.queryrouter.models.dao;

import vault.queryrouter.common.TenantUpdateJobStatus;
import vault.queryrouter.common.TenantUpdateJobType;
import vault.queryrouter.models.Query;
import vault.queryrouter.models.TenantUpdateJob;
import org.hibernate.Criteria;
import org.hibernate.HibernateException;
import org.hibernate.StatelessSession;
import org.hibernate.criterion.Expression;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.Iterator;

public class JobQueueDAO {

    public static Logger logger = LoggerFactory.getLogger(JobQueueDAO.class);

    public static Integer addQueryToJobQueue(StatelessSession session, String sql, TenantUpdateJobStatus status,
            String queryId, String connectionId, int tenantMppdbId) {
        TenantUpdateJob log = new TenantUpdateJob(sql, status.toString(), queryId, connectionId,
                TenantUpdateJobType.queryrouter, tenantMppdbId);
        return (Integer) session.insert(log);
    }

    public static int getProcessingQuery(StatelessSession session, int tenantMppdbId) {
        int counter = 0;

        Criteria criteria = session.createCriteria(TenantUpdateJob.class);
        criteria.add(Expression.eq("status", TenantUpdateJobStatus.Processing.toString()));
        criteria.add(Expression.or(Expression.eq("action", "tenant_mppdb_data_movement"),
                Expression.eq("action", "mppdb_copy")));
        criteria.add(Expression.eq("tenantMppdbId", tenantMppdbId));
        Iterator updateJobs = criteria.list().iterator();

        if (updateJobs != null) {
            while (updateJobs.hasNext()) {
                updateJobs.next();
                counter++;
            }
        }

        return counter;
    }

    public static void deleteFromJobQueue(StatelessSession session, int logID) {
        TenantUpdateJob query = (TenantUpdateJob) session.get(TenantUpdateJob.class, logID);
        session.delete(query);
    }

    public static TenantUpdateJob getPendingQueryLock(StatelessSession session, String workerId) throws Exception {

        try {
            session.getTransaction().begin();
            //Update the pending query(order by last_touch_timestamp) status from pending to processing
            String hql = "UPDATE TenantUpdateJob set status= '" + TenantUpdateJobStatus.Processing.toString()
                    + "', workerId = '" + workerId + "' WHERE status='" + TenantUpdateJobStatus.Pending.toString()
                    + "' AND type ='" + TenantUpdateJobType.queryrouter.toString()
                    + "' ORDER BY lastTouchTime LIMIT 1";
            org.hibernate.Query query = session.createQuery(hql);
            int result = query.executeUpdate();
            session.getTransaction().commit();

            //Pending query exists and the status changes from "Pending" to "Processing"
            if (result != 0) {

                //Find the processing query by the thread(workerId)
                Criteria criteria = session.createCriteria(TenantUpdateJob.class);
                criteria.add(Expression.eq("workerId", workerId.toString()));
                criteria.add(Expression.eq("status", TenantUpdateJobStatus.Processing.toString()));
                TenantUpdateJob pendingQueueCandidate = (TenantUpdateJob) criteria.uniqueResult();

                Query q = QueryDAO.getQuery(session, pendingQueueCandidate.getQueryId());

                //Check the availability of the processing Query that could be actual processed
                //If the number of  conflictQuery is more than 0 which means the processing query conflicts with the another processing query(e.g.move_tenant_mppdb_data)
                int conflictQuery = JobQueueDAO.getProcessingQuery(session, q.getTenantMppdbId());

                //No conflict query -> Return the query(TenantUpdateJob Object)
                if (conflictQuery == 0) {

                    return pendingQueueCandidate;
                }
                //Conflict query exists -> Status of the processing query turn back to "Pending" and the last_touch_timestamp will be updated
                else {

                    try {
                        session.getTransaction().begin();
                        TenantUpdateJob jq = (TenantUpdateJob) session.get(TenantUpdateJob.class,
                                pendingQueueCandidate.getJobQueueId());
                        jq.setStatus(TenantUpdateJobStatus.Pending.toString());
                        jq.setWorkerId("");
                        session.update(jq);
                        session.getTransaction().commit();

                    } catch (HibernateException e) {
                        logger.error("Exception: ", e);
                        if (session.getTransaction() != null)
                            session.getTransaction().rollback();
                        e.printStackTrace();
                    }
                    return null;
                }
            }
            //No pending query exists
            else {
                return null;
            }

        } catch (Exception e) {
            logger.error(e.toString());
            throw e;
        }
    }

}