SipManagerDelegate.java

/*
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.mobicents.servlet.sip.core.session;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.ConcurrentHashMap;

import javax.servlet.ServletException;
import javax.servlet.http.HttpSession;

import org.apache.catalina.Container;
import org.apache.log4j.Logger;
import org.mobicents.servlet.sip.message.SipFactoryImpl;
import org.mobicents.servlet.sip.startup.SipContext;

/**
 * This class handles the management of sip sessions and sip application sessions for a given container (context)
 * It is a delegate since it is used by many manager implementations classes (Standard and clustered ones) 
 * 
 * @author <A HREF="mailto:jean.deruelle@gmail.com">Jean Deruelle</A> 
 *
 */
public abstract class SipManagerDelegate {

	private static transient Logger logger = Logger.getLogger(SipManagerDelegate.class);
	
	protected ConcurrentHashMap<SipApplicationSessionKey, MobicentsSipApplicationSession> sipApplicationSessions = 
		new ConcurrentHashMap<SipApplicationSessionKey, MobicentsSipApplicationSession>();

	protected ConcurrentHashMap<String, MobicentsSipApplicationSession> sipApplicationSessionsByAppGeneratedKey = 
		new ConcurrentHashMap<String, MobicentsSipApplicationSession>();
	
	//if it's never cleaned up a memory leak will occur
	//Shall we have a thread scanning for invalid sessions and removing them accordingly ?
	//=> after a chat with ranga the better way to go for now is removing on processDialogTerminated
	protected ConcurrentHashMap<SipSessionKey, MobicentsSipSession> sipSessions = 
		new ConcurrentHashMap<SipSessionKey, MobicentsSipSession>();

	protected SipFactoryImpl sipFactoryImpl;
	
	protected Container container;

	/**
     * The maximum number of active Sip Sessions allowed, or -1 for no limit.
     */
    protected int maxActiveSipSessions = -1;
    
    /**
     * The maximum number of active Sip Application Sessions allowed, or -1 for no limit.
     */
    protected int maxActiveSipApplicationSessions = -1;
    
    /**
     * Number of sip session creations that failed due to maxActiveSipSessions.
     */
    protected int rejectedSipSessions = 0;

    /**
     * Number of sip application session creations that failed due to maxActiveSipApplicationSessions.
     */
    protected int rejectedSipApplicationSessions = 0;

    
    /**
     * The longest time (in seconds) that an expired sip session had been alive.
     */
    protected int sipSessionMaxAliveTime;


    /**
     * Average time (in seconds) that expired sip sessions had been alive.
     */
    protected int sipSessionAverageAliveTime;


    /**
     * Number of sip sessions that have expired.
     */
    protected int expiredSipSessions = 0;
    
    /**
     * The longest time (in seconds) that an expired Sip Application session had been alive.
     */
    protected int sipApplicationSessionMaxAliveTime;


    /**
     * Average time (in seconds) that expired Sip Application Sessions had been alive.
     */
    protected int sipApplicationSessionAverageAliveTime;


    /**
     * Number of sip application sessions that have expired.
     */
    protected int expiredSipApplicationSessions = 0;
    
    // Number of sip sessions created by this manager
    protected int sipSessionCounter=0;
    
    // Number of sip Application sessions created by this manager
    protected int sipApplicationSessionCounter=0;
	
	/**
	 * @return the SipFactoryImpl
	 */
	public SipFactoryImpl getSipFactoryImpl() {
		return sipFactoryImpl;
	}

	/**
	 * @param sipFactoryImpl the SipFactoryImpl to set
	 */
	public void setSipFactoryImpl(SipFactoryImpl sipFactoryImpl) {
		this.sipFactoryImpl = sipFactoryImpl;
	}

	/**
	 * @return the container
	 */
	public Container getContainer() {
		return container;
	}

	/**
	 * @param container the container to set
	 */
	public void setContainer(Container container) {
		this.container = container;
	}
	
	/**
	 * Removes a sip session from the manager by its key
	 * @param key the identifier for this session
	 * @return the sip session that had just been removed, null otherwise
	 */
	public MobicentsSipSession removeSipSession(final SipSessionKey key) {
		if(logger.isDebugEnabled()) {
			logger.debug("Removing a sip session with the key : " + key);
		}
		return sipSessions.remove(key);
	}
	
	/**
	 * Removes a sip application session from the manager by its key
	 * @param key the identifier for this session
	 * @return the sip application session that had just been removed, null otherwise
	 */
	public MobicentsSipApplicationSession removeSipApplicationSession(final SipApplicationSessionKey key) {
		if(logger.isDebugEnabled()) {
			logger.debug("Removing a sip application session with the key : " + key);
		}
		MobicentsSipApplicationSession sipApplicationSession  = sipApplicationSessions.remove(key);
		if(sipApplicationSession != null) {
			final String appGeneratedKey = sipApplicationSession.getKey().getAppGeneratedKey();
			if(appGeneratedKey != null) {
				sipApplicationSessionsByAppGeneratedKey.remove(appGeneratedKey);
			}
		}
		return sipApplicationSession;
	}
	
	/**
	 * Retrieve a sip application session from its key. If none exists, one can enforce
	 * the creation through the create parameter to true.
	 * @param key the key identifying the sip application session to retrieve 
	 * @param create if set to true, if no session has been found one will be created
	 * @return the sip application session matching the key
	 */
	public MobicentsSipApplicationSession getSipApplicationSession(final SipApplicationSessionKey key, final boolean create) {		
		MobicentsSipApplicationSession sipApplicationSessionImpl = null;
		//first we check if the app session can be found by its app generated key
		final String appGeneratedKey = key.getAppGeneratedKey();
		if(appGeneratedKey != null) {
			sipApplicationSessionImpl = sipApplicationSessionsByAppGeneratedKey.get(appGeneratedKey);
		}
		if(sipApplicationSessionImpl == null) {
			sipApplicationSessionImpl = sipApplicationSessions.get(key);
		}
		if(sipApplicationSessionImpl == null && create) {
			sipApplicationSessionImpl =  createSipApplicationSession(key, create);						
		}
		return sipApplicationSessionImpl;
	}	

	protected MobicentsSipApplicationSession createSipApplicationSession(final SipApplicationSessionKey key, final boolean create) {
		//http://dmy999.com/article/34/correct-use-of-concurrenthashmap
		MobicentsSipApplicationSession sipApplicationSessionImpl = null;
		final MobicentsSipApplicationSession newSipApplicationSessionImpl = 
			getNewMobicentsSipApplicationSession(key, (SipContext) container);
		sipApplicationSessionImpl = sipApplicationSessions.putIfAbsent(key, newSipApplicationSessionImpl);		
		if (sipApplicationSessionImpl == null) {
			// put succeeded, use new value
			if(logger.isDebugEnabled()) {
				logger.debug("Adding a sip application session with the key : " + key);
			}
            sipApplicationSessionImpl = newSipApplicationSessionImpl;
            final String appGeneratedKey = key.getAppGeneratedKey(); 
    		if(appGeneratedKey != null) {    		
            	sipApplicationSessionsByAppGeneratedKey.putIfAbsent(appGeneratedKey, sipApplicationSessionImpl);
            }
        }		
		return sipApplicationSessionImpl;
	}

	/**
	 * Retrieve a sip session from its key. If none exists, one can enforce
	 * the creation through the create parameter to true. the sip factory cannot be null
	 * if create is set to true.
	 * @param key the key identifying the sip session to retrieve 
	 * @param create if set to true, if no session has been found one will be created
	 * @param sipFactoryImpl needed only for sip session creation.
	 * @param sipApplicationSessionImpl to associate the SipSession with if create is set to true, if false it won't be used
	 * @return the sip session matching the key
	 * @throws IllegalArgumentException if create is set to true and sip Factory is null
	 */
	public MobicentsSipSession getSipSession(final SipSessionKey key, final boolean create, final SipFactoryImpl sipFactoryImpl, final MobicentsSipApplicationSession sipApplicationSessionImpl) {
		if(create && sipFactoryImpl == null) {
			throw new IllegalArgumentException("the sip factory should not be null");
		}
		//http://dmy999.com/article/34/correct-use-of-concurrenthashmap
		MobicentsSipSession sipSessionImpl = sipSessions.get(key);
		if(sipSessionImpl == null && create) {
			sipSessionImpl =  createSipSession(key, create, sipFactoryImpl, sipApplicationSessionImpl);
		}
		// check if this session key has a to tag.
		if(sipSessionImpl != null) {
			return setToTag(key, sipSessionImpl);
		}
		return sipSessionImpl;
	}
	
	protected MobicentsSipSession createSipSession(final SipSessionKey key, final boolean create, final SipFactoryImpl sipFactoryImpl, final MobicentsSipApplicationSession sipApplicationSessionImpl) {
		MobicentsSipSession sipSessionImpl = null;
		final MobicentsSipSession newSipSessionImpl = getNewMobicentsSipSession(key, sipFactoryImpl, sipApplicationSessionImpl);
		sipSessionImpl = sipSessions.putIfAbsent(key, newSipSessionImpl);
		if(sipSessionImpl == null) {
			if(logger.isDebugEnabled()) {
				logger.debug("Adding a sip session with the key : " + key);
			}
			// put succeeded, use new value
            sipSessionImpl = newSipSessionImpl;
		}
		return sipSessionImpl;
	}
	
	protected MobicentsSipSession setToTag(final SipSessionKey key, final MobicentsSipSession sipSession) {
		final String currentKeyToTag = key.getToTag();
		final SipSessionKey existingKey = sipSession.getKey();
		final String toTag = existingKey.getToTag();
		if(toTag == null && currentKeyToTag != null) {
			existingKey.setToTag(currentKeyToTag );
			if(logger.isDebugEnabled()) {
				logger.debug("Setting the To tag " + currentKeyToTag + 
						" to the session " + key);
			}
		} else if (currentKeyToTag != null && !toTag.equals(currentKeyToTag)) {
			MobicentsSipSession derivedSipSession = sipSession.findDerivedSipSession(currentKeyToTag );
			if(derivedSipSession == null) {
				// if the to tag is different a sip session is created
				if(logger.isDebugEnabled()) {
					logger.debug("Original session " + key + " with To Tag " + toTag + 
							" creates new derived session with following to Tag " + currentKeyToTag );
				}
				derivedSipSession = createDerivedSipSession(sipSession, key);
			} else {
				if(logger.isDebugEnabled()) {
					logger.debug("Original session " + key + " with To Tag " + toTag + 
							" already has a derived session with following to Tag " + currentKeyToTag  + " - reusing it");
				}
			}
			return derivedSipSession;	
		}
		return sipSession;
	}
	
	public void changeSessionKey(SipSessionKey oldKey, SipSessionKey newKey) {
		MobicentsSipSession session = this.sipSessions.get(oldKey);
		if(session == null)
			throw new IllegalArgumentException("oldKey doesn't exist in this application session.");
		this.sipSessions.put(newKey, session);
		this.sipSessions.remove(oldKey);
	}

	/**
	 * clone the parent sip session given in parameter except its attributes (they will be shared) 
	 * and add it to the internal map of derived sessions identifying it by its ToTag
	 * 
	 * @param parentSipSession the parent sip session holding the newly created derived session
	 * @param sessionKey the key of the new derived session to create
	 * @return the newly created derived session
	 */
	protected MobicentsSipSession createDerivedSipSession(MobicentsSipSession parentSipSession, SipSessionKey sessionKey) {
		// clone the session and add it to the map of derived sessions
		MobicentsSipSession sipSessionImpl = getNewMobicentsSipSession(sessionKey, sipFactoryImpl, parentSipSession.getSipApplicationSession());
		sipSessionImpl.setSipSessionAttributeMap(parentSipSession.getSipSessionAttributeMap());
		try {
			sipSessionImpl.setHandler(parentSipSession.getHandler());
		} catch (ServletException e) {
			//cannot happen
			logger.error("Problem creating derived session", e);
		}
		sipSessionImpl.setRoutingRegion(parentSipSession.getRegion());
		// dialog will be set when the response will be associated with this session
//		sipSessionImpl.sessionCreatingDialog = dialog;
		sipSessionImpl.setState(parentSipSession.getState());
		sipSessionImpl.setStateInfo(parentSipSession.getStateInfo());
		sipSessionImpl.setProxy(parentSipSession.getProxy());
		if(parentSipSession.getSipSubscriberURI() != null) {
			sipSessionImpl.setSipSubscriberURI(parentSipSession.getSipSubscriberURI().clone());
		}
		sipSessionImpl.setUserPrincipal(parentSipSession.getUserPrincipal());
		sipSessionImpl.setParentSession(parentSipSession);
		
		parentSipSession.addDerivedSipSessions(sipSessionImpl);
		
		return sipSessionImpl;
	}

	/**
	 * Retrieve all sip sessions currently hold by the session manager
	 * @return an iterator on the sip sessions
	 */
	public Iterator<MobicentsSipSession> getAllSipSessions() {
		
		return sipSessions.values().iterator();
	}

	/**
	 * Retrieve all sip application sessions currently hold by the session manager
	 * @return an iterator on the sip sessions
	 */
	public int getNumberOfSipApplicationSessions() {
		return sipApplicationSessions.size();
	}
	
	/**
	 * Retrieve all sip sessions currently hold by the session manager
	 * @return an iterator on the sip sessions
	 */
	public int getNumberOfSipSessions() {
		
		return sipSessions.size();
	}

	/**
	 * Retrieve all sip application sessions currently hold by the session manager
	 * @return an iterator on the sip sessions
	 */
	public Iterator<MobicentsSipApplicationSession> getAllSipApplicationSessions() {
		return sipApplicationSessions.values().iterator();
	}
	
	/**
	 * Retrieves the sip application session holding the converged http session in parameter
	 * @param convergedHttpSession the converged session to look up
	 * @return the sip application session holding a reference to it or null if none references it
	 */
	public MobicentsSipApplicationSession findSipApplicationSession(HttpSession httpSession) {
		for (MobicentsSipApplicationSession sipApplicationSessionImpl : sipApplicationSessions.values()) {			
			if(sipApplicationSessionImpl.findHttpSession(httpSession.getId()) != null) {
				return sipApplicationSessionImpl;
			}
		}
		return null;
	}

	/**
	 * 
	 */
	public void dumpSipSessions() {
		if(logger.isDebugEnabled()) {
			logger.debug("sip sessions present in the session manager");
		
			for (SipSessionKey sipSessionKey : sipSessions.keySet()) {
				logger.debug(sipSessionKey.toString());
			}
		}
	}

	/**
	 * 
	 */
	public void dumpSipApplicationSessions() {
		if(logger.isDebugEnabled()) {
			logger.debug("sip application sessions present in the session manager");
		
			for (SipApplicationSessionKey sipApplicationSessionKey : sipApplicationSessions.keySet()) {
				logger.debug(sipApplicationSessionKey.toString() + "/hashed_app_name=" + sipFactoryImpl.getSipApplicationDispatcher().getHashFromApplicationName(sipApplicationSessionKey.getApplicationName()));
			}
		}
	}

	
	/**
	 * Remove the sip sessions and sip application sessions 
	 */
	public void removeAllSessions() {		
		List<SipSessionKey> sipSessionsToRemove = new ArrayList<SipSessionKey>(); 
		for (SipSessionKey sipSessionKey : sipSessions.keySet()) {
			sipSessionsToRemove.add(sipSessionKey);
		}
		for (SipSessionKey sipSessionKey : sipSessionsToRemove) {
			removeSipSession(sipSessionKey);
		}
		List<SipApplicationSessionKey> sipApplicationSessionsToRemove = new ArrayList<SipApplicationSessionKey>(); 
		for (SipApplicationSessionKey sipApplicationSessionKey : sipApplicationSessions.keySet()) {
			sipApplicationSessionsToRemove.add(sipApplicationSessionKey);
		}
		for (SipApplicationSessionKey sipApplicationSessionKey : sipApplicationSessionsToRemove) {
			removeSipApplicationSession(sipApplicationSessionKey);
		}				
	}
	
	protected abstract MobicentsSipSession getNewMobicentsSipSession(SipSessionKey key, SipFactoryImpl sipFactoryImpl, MobicentsSipApplicationSession mobicentsSipApplicationSession);
	
	protected abstract MobicentsSipApplicationSession getNewMobicentsSipApplicationSession(SipApplicationSessionKey key, SipContext sipContext);
	
	//JMX statistics
	/**
	 * Return the maximum number of active Sessions allowed, or -1 for no limit.
	 */
	public int getMaxActiveSipSessions() {
		return (this.maxActiveSipSessions);
	}

	/**
	 * Set the maximum number of actives Sip Sessions allowed, or -1 for no
	 * limit.
	 * 
	 * @param max
	 *            The new maximum number of sip sessions
	 */
	public void setMaxActiveSipSessions(int max) {
		this.maxActiveSipSessions = max;
	}

	/**
	 * Return the maximum number of active Sessions allowed, or -1 for no limit.
	 */
	public int getMaxActiveSipApplicationSessions() {
		return (this.maxActiveSipApplicationSessions);
	}

	/**
	 * Set the maximum number of actives Sip Application Sessions allowed, or -1
	 * for no limit.
	 * 
	 * @param max
	 *            The new maximum number of sip application sessions
	 */
	public void setMaxActiveSipApplicationSessions(int max) {
		this.maxActiveSipApplicationSessions = max;
	}

	/**
	 * Number of sip session creations that failed due to maxActiveSipSessions
	 * 
	 * @return The count
	 */
	public int getRejectedSipSessions() {
		return rejectedSipSessions;
	}

	public void setRejectedSipSessions(int rejectedSipSessions) {
		this.rejectedSipSessions = rejectedSipSessions;
	}

	/**
	 * Number of sip session creations that failed due to maxActiveSipSessions
	 * 
	 * @return The count
	 */
	public int getRejectedSipApplicationSessions() {
		return rejectedSipApplicationSessions;
	}

	public void setRejectedSipApplicationSessions(
			int rejectedSipApplicationSessions) {
		this.rejectedSipApplicationSessions = rejectedSipApplicationSessions;
	}

	public void setSipSessionCounter(int sipSessionCounter) {
		this.sipSessionCounter = sipSessionCounter;
	}

	/**
	 * Total sessions created by this manager.
	 * 
	 * @return sessions created
	 */
	public int getSipSessionCounter() {
		return sipSessionCounter;
	}

	/**
	 * Returns the number of active sessions
	 * 
	 * @return number of sessions active
	 */
	public int getActiveSipSessions() {
		return sipSessions.size();
	}

	/**
	 * Gets the longest time (in seconds) that an expired session had been
	 * alive.
	 * 
	 * @return Longest time (in seconds) that an expired session had been alive.
	 */
	public int getSipSessionMaxAliveTime() {
		return sipSessionMaxAliveTime;
	}

	/**
	 * Sets the longest time (in seconds) that an expired session had been
	 * alive.
	 * 
	 * @param sessionMaxAliveTime
	 *            Longest time (in seconds) that an expired session had been
	 *            alive.
	 */
	public void setSipSessionMaxAliveTime(int sipSessionMaxAliveTime) {
		this.sipSessionMaxAliveTime = sipSessionMaxAliveTime;
	}

	/**
	 * Gets the average time (in seconds) that expired sessions had been alive.
	 * 
	 * @return Average time (in seconds) that expired sessions had been alive.
	 */
	public int getSipSessionAverageAliveTime() {
		return sipSessionAverageAliveTime;
	}

	/**
	 * Sets the average time (in seconds) that expired sessions had been alive.
	 * 
	 * @param sessionAverageAliveTime
	 *            Average time (in seconds) that expired sessions had been
	 *            alive.
	 */
	public void setSipSessionAverageAliveTime(int sipSessionAverageAliveTime) {
		this.sipSessionAverageAliveTime = sipSessionAverageAliveTime;
	}

	public void setSipApplicationSessionCounter(int sipApplicationSessionCounter) {
		this.sipApplicationSessionCounter = sipApplicationSessionCounter;
	}

	/**
	 * Total sessions created by this manager.
	 * 
	 * @return sessions created
	 */
	public int getSipApplicationSessionCounter() {
		return sipApplicationSessionCounter;
	}

	/**
	 * Returns the number of active sessions
	 * 
	 * @return number of sessions active
	 */
	public int getActiveSipApplicationSessions() {
		return sipApplicationSessions.size();
	}

	/**
	 * Gets the longest time (in seconds) that an expired session had been
	 * alive.
	 * 
	 * @return Longest time (in seconds) that an expired session had been alive.
	 */
	public int getSipApplicationSessionMaxAliveTime() {
		return sipApplicationSessionMaxAliveTime;
	}

	/**
	 * Sets the longest time (in seconds) that an expired session had been
	 * alive.
	 * 
	 * @param sessionMaxAliveTime
	 *            Longest time (in seconds) that an expired session had been
	 *            alive.
	 */
	public void setSipApplicationSessionMaxAliveTime(
			int sipApplicationSessionMaxAliveTime) {
		this.sipApplicationSessionMaxAliveTime = sipApplicationSessionMaxAliveTime;
	}

	/**
	 * Gets the average time (in seconds) that expired sessions had been alive.
	 * 
	 * @return Average time (in seconds) that expired sessions had been alive.
	 */
	public int getSipApplicationSessionAverageAliveTime() {
		return sipApplicationSessionAverageAliveTime;
	}

	/**
	 * Sets the average time (in seconds) that expired sessions had been alive.
	 * 
	 * @param sessionAverageAliveTime
	 *            Average time (in seconds) that expired sessions had been
	 *            alive.
	 */
	public void setSipApplicationSessionAverageAliveTime(
			int sipApplicationSessionAverageAliveTime) {
		this.sipApplicationSessionAverageAliveTime = sipApplicationSessionAverageAliveTime;
	}

	/**
	 * Gets the number of sessions that have expired.
	 * 
	 * @return Number of sessions that have expired
	 */
	public int getExpiredSipSessions() {
		return expiredSipSessions;
	}

	/**
	 * Sets the number of sessions that have expired.
	 * 
	 * @param expiredSessions
	 *            Number of sessions that have expired
	 */
	public void setExpiredSipSessions(int expiredSipSessions) {
		this.expiredSipSessions = expiredSipSessions;
	}

	/**
	 * Gets the number of sessions that have expired.
	 * 
	 * @return Number of sessions that have expired
	 */
	public int getExpiredSipApplicationSessions() {
		return expiredSipApplicationSessions;
	}

	/**
	 * Sets the number of sessions that have expired.
	 * 
	 * @param expiredSessions
	 *            Number of sessions that have expired
	 */
	public void setExpiredSipApplicationSessions(
			int expiredSipApplicationSessions) {
		this.expiredSipApplicationSessions = expiredSipApplicationSessions;
	}
}