Merge pull request #728 from ritzalam/keep-track-of-user-connections

- keep track of user's number of connections to red5 to manage auto-…

akka-bbb-apps/src/main/scala/org/bigbluebutton/core/apps/UsersApp.scala

@@ -302,7 +302,7 @@ trait UsersApp {
       outGW.send(new MeetingState(mProps.meetingID, mProps.recorded, uvo.userID, meetingModel.getPermissions(), meetingModel.isMeetingMuted()))
 
       // Become presenter if the only moderator		
-      if (usersModel.numModerators == 1) {
+      if ((usersModel.numModerators == 1) || (usersModel.noPresenter())) {
         if (ru.role == Role.MODERATOR) {
           assignNewPresenter(msg.userID, ru.name, msg.userID)
         }

akka-bbb-apps/src/main/scala/org/bigbluebutton/core/apps/UsersModel.scala

@@ -96,6 +96,10 @@ class UsersModel {
     uservos.values find (u => u.role == MODERATOR)
   }
 
+  def noPresenter(): Boolean = {
+    !getCurrentPresenter().isDefined
+  }
+
   def getCurrentPresenter(): Option[UserVO] = {
     uservos.values find (u => u.presenter == true)
   }

bigbluebutton-apps/src/main/java/org/bigbluebutton/red5/BigBlueButtonApplication.java

@@ -42,6 +42,8 @@ public class BigBlueButtonApplication extends MultiThreadedApplicationAdapter {
 	private ConnectionInvokerService connInvokerService;
 	private MessagePublisher red5InGW;
 	
+	private final UserConnectionMapper userConnections = new UserConnectionMapper();
+	
 	private final String APP = "BBB";
 	private final String CONN = "RED5-";
 	
@@ -166,6 +168,8 @@ public class BigBlueButtonApplication extends MultiThreadedApplicationAdapter {
 		
 		log.info("User joining bbb-apps: data={}", logStr);
 		
+		userConnections.addUserConnection(userId, connId);
+		
 		return super.roomConnect(connection, params);
         
 	}
@@ -214,10 +218,15 @@ public class BigBlueButtonApplication extends MultiThreadedApplicationAdapter {
 	    Gson gson = new Gson();
 	    String logStr =  gson.toJson(logData);
 	        
-	    log.info("User leaving bbb-apps: data={}", logStr);
-	      	        
-	    red5InGW.userLeft(bbbSession.getRoom(), getBbbSession().getInternalUserID(), sessionId);
-		
+	    boolean removeUser = userConnections.userDisconnected(userId, connId);
+	    
+	    if (removeUser) {
+	    	log.info("User leaving bbb-apps: data={}", logStr);
+	    	red5InGW.userLeft(bbbSession.getRoom(), getBbbSession().getInternalUserID(), sessionId);
+	    } else {
+	    	log.info("User not leaving bbb-apps but just disconnected: data={}", logStr);
+	    }
+	    
 		super.roomDisconnect(conn);
 	}
 	

bigbluebutton-apps/src/main/java/org/bigbluebutton/red5/UserConnectionMapper.java

@@ -0,0 +1,70 @@
+package org.bigbluebutton.red5;
+
+import java.util.HashSet;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+
+/**
+ * This class maintains the connections mapping of a user.
+ * This tracks the connections for a user to manage auto-reconnects.
+ * @author ralam
+ *
+ */
+public class UserConnectionMapper {
+
+	private ConcurrentMap<String, UserConnection> users = new ConcurrentHashMap<String, UserConnection>(8, 0.9f, 1);;
+	
+	/**
+	 * Adds a connection for a user.
+	 * @param userId
+	 * @param connId
+	 */
+	public synchronized void addUserConnection(String userId, String connId) {
+		if (users.containsKey(userId)) {
+			UserConnection user = users.get(userId);
+			user.add(connId);
+		} else {
+			UserConnection user = new UserConnection();
+			user.add(connId);
+			users.put(userId, user);
+		}
+	}
+	
+	/**
+	 * Removed a connection for a user. Returns true if the user doesn't have any
+	 * connection left and thus can be removed.
+	 * @param userId
+	 * @param connId
+	 * @return boolean - no more connections
+	 */
+	public synchronized boolean userDisconnected(String userId, String connId) {
+		if (users.containsKey(userId)) {
+			UserConnection user = users.get(userId);
+			user.remove(connId);
+			if (user.isEmpty()) {
+				users.remove(userId);
+				return true;
+			} 
+			return false;
+		}
+		
+		return true;		
+	}
+	
+	private class UserConnection {
+		private final Set<String> connections = new HashSet<String>();
+		
+		public void add(String connId) {
+			connections.add(connId);
+		}
+		
+		public void remove(String connId) {
+			connections.remove(connId);
+		}
+		
+		public boolean isEmpty() {
+			return connections.isEmpty();
+		}
+	}
+}