Package org.cometd.oort

Class Seti

  • All Implemented Interfaces:
    org.eclipse.jetty.util.component.Dumpable, org.eclipse.jetty.util.component.LifeCycle
    @ManagedObject("CometD cloud peer discovery component")
public class Seti
extends org.eclipse.jetty.util.component.AbstractLifeCycle
implements org.eclipse.jetty.util.component.Dumpable

    The component that Searches for Extra Terrestrial Intelligence or, in this case, just searches for a user logged onto a comet in an Oort cloud.

    Seti allows an application to maintain a mapping from userId (any application identifier such as user names or database IDs that represent users) to server sessions using the associate(String, ServerSession) and disassociate(String, ServerSession) methods.

    A typical example of usage of associate(String, ServerSession) is in a SecurityPolicy after a successful handshake (where authentication information can be linked with the server session), or in CometD services where the association is established upon receiving a message on a particular channel processed by the service itself.

    Each comet in the cluster keeps its own mapping for clients connected to it.

    The sendMessage(Collection, String, Object) and sendMessage(String, String, Object) methods may be used to send messages to user(s) anywhere in the Oort cluster and Seti organizes the search in order to locate the user(s).

    See Also:
    SetiServlet

    • Field Detail

      • SETI_ATTRIBUTE

        public static final String SETI_ATTRIBUTE

    • Constructor Detail

      • Seti

        public Seti​(Oort oort)

    • Method Detail

      • getOort

        @ManagedAttribute(value="The Oort of this Seti",
                  readonly=true)
public Oort getOort()

      • getId

        @ManagedAttribute(value="The unique ID of this Seti",
                  readonly=true)
public String getId()

      • doStart

        protected void doStart()
        Overrides:
        doStart in class org.eclipse.jetty.util.component.AbstractLifeCycle

      • doStop

        protected void doStop()
        Overrides:
        doStop in class org.eclipse.jetty.util.component.AbstractLifeCycle

      • generateSetiId

        protected String generateSetiId​(String oortURL)

      • generateSetiChannel

        protected String generateSetiChannel​(String setiId)

      • associate

        public boolean associate​(String userId,
                         ServerSession session)

        Associates the given userId to the given session.

        If it is the first association for this userId, broadcasts this information on the Oort cloud, so that other comets will know that the given userId is on this comet.

        Parameters:
        userId - the user identifier to associate
        session - the session to map the userId to
        Returns:
        true if the session has been associated, false if it was already associated
        See Also:
        isAssociated(String), disassociate(String, ServerSession)

      • getAssociationCount

        @ManagedOperation(value="The number of local associations for the given userId",
                  impact="INFO")
public int getAssociationCount​(@Name(value="userId",description="The userId to test for local association count")
                               String userId)
        Parameters:
        userId - the user identifier to test for association count
        Returns:
        the number of local associations
        See Also:
        isAssociated(String), getPresenceCount(String)

      • isPresent

        @ManagedOperation(value="Whether the given userId is present in the cloud",
                  impact="INFO")
public boolean isPresent​(@Name(value="userId",description="The userId to test for presence in the cloud")
                         String userId)
        Parameters:
        userId - the user identifier to test for presence
        Returns:
        whether the given userId is present on the cloud (and therefore has been associated either locally or remotely)
        See Also:
        isAssociated(String), getPresenceCount(String)

      • getPresenceCount

        @ManagedOperation(value="The number of local and remote associations for the given userId",
                  impact="INFO")
public int getPresenceCount​(@Name(value="userId",description="The userId to test for presence count")
                            String userId)
        Parameters:
        userId - the user identifier to test for presence count
        Returns:
        the number of associations (local or remote) on the cloud
        See Also:
        isPresent(String), getAssociationCount(String)

      • disassociate

        public boolean disassociate​(String userId,
                            ServerSession session)

        Disassociates the given userId from the given session.

        If this is the last disassociation for this userId, broadcasts this information on the Oort cloud, so that other comets will know that the given userId no longer is on this comet.

        Parameters:
        userId - the user identifier to disassociate
        session - the session mapped to the userId
        Returns:
        true if the session has been disassociated, false if it was not associated
        See Also:
        associate(String, ServerSession)

      • disassociate

        public Set<ServerSession> disassociate​(String userId)

        Disassociates the given userId from all sessions.

        If this user had sessions on this comet, broadcast this information on the Oort cloud, so that other comets will know that the given userId no longer is on this comet.

        Parameters:
        userId - the user identifier to disassociate
        Returns:
        set of sessions that were disassociated
        See Also:
        associate(String, ServerSession)

      • removeAssociationsAndPresences

        protected void removeAssociationsAndPresences()

      • removePresences

        protected void removePresences​(String oortURL)

      • getUserIds

        @ManagedAttribute(value="The set of userIds known to this Seti",
                  readonly=true)
public Set<String> getUserIds()
        Returns:
        the set of userIds known to this Seti, both local and remote

      • sendMessage

        public void sendMessage​(String toUserId,
                        String toChannel,
                        Object data)

        Sends a message to the given userId in the Oort cloud.

        Parameters:
        toUserId - the userId to send the message to
        toChannel - the channel to send the message to
        data - the content of the message
        See Also:
        sendMessage(Collection, String, Object)

      • sendMessage

        public void sendMessage​(Collection<String> toUserIds,
                        String toChannel,
                        Object data)

        Sends a message to multiple userIds in the Oort cloud.

        Parameters:
        toUserIds - the userIds to send the message to
        toChannel - the channel to send the message to
        data - the content of the message

      • receiveDirect

        protected void receiveDirect​(Message message)

        Receives messages directly from other Setis in the cloud, containing messages to be delivered to sessions connected to this comet.

        Parameters:
        message - the message to deliver to a session connected to this comet

      • receiveBroadcast

        protected void receiveBroadcast​(Message message)

        Receives messages broadcast by other Setis in the cloud.

        Broadcast messages may be presence messages, where another Seti advertises an association, or fallback messages. Fallback messages are messages that were sent to a particular Seti because the sender thought the target userId was there, but the receiving Seti does not know that userId anymore (for example, it just disconnected); in this case, the receiving Seti broadcasts the message to the whole cloud, in the hope that the user can be found in some other comet of the cloud.

        Parameters:
        message - the message to possibly deliver to a session connected to this comet

      • receivePresence

        protected void receivePresence​(Map<String,​Object> presence)

        Receives a presence message.

        Parameters:
        presence - the presence message received

      • receiveLocalPresence

        protected void receiveLocalPresence​(Map<String,​Object> presence)

      • receiveRemotePresence

        protected void receiveRemotePresence​(Map<String,​Object> presence)

      • removePresenceListeners

        public void removePresenceListeners()

      • receiveMessage

        protected void receiveMessage​(Map<String,​Object> message)

        Receives a seti message.

        Parameters:
        message - the seti message received

      • toString

        public String toString()
        Overrides:
        toString in class org.eclipse.jetty.util.component.AbstractLifeCycle