/** * remove a SRDI cache entry * * @param peer peer id we send the request, null for sending to all * @param id peer id of the SRDI route that we want to remove from the cache */ protected void removeSrdi(String peer, PeerID id) { SrdiMessage srdiMsg; try { srdiMsg = new SrdiMessageImpl( group.getPeerID(), 1, // only one hop "route", id.toString(), null, // 0 means remove new Long(0).longValue()); if (LOG.isEnabledFor(Level.DEBUG)) { LOG.debug("sending a router SRDI message delete route " + id); } if (peer == null) { PeerID destPeer = srdi.getReplicaPeer(id.toString()); // don't push anywhere if we do not have replica // or we are trying to push to ouself if (destPeer != null && (!destPeer.equals(localPeerId))) { srdi.pushSrdi(destPeer, srdiMsg); } } } catch (Exception e) { if (LOG.isEnabledFor(Level.DEBUG)) { LOG.debug("Removing srdi entry failed", e); } } }
/* * push srdi entries to the SRDI rendezvous cache * @param all if true push all entries, otherwise just deltas */ protected void pushSrdi(ID peer, PeerID id) { SrdiMessage srdiMsg; try { srdiMsg = new SrdiMessageImpl( group.getPeerID(), 1, // only one hop "route", id.toString(), null, new Long(Long.MAX_VALUE).longValue()); // maximum expiration // 10182002tra:Route info don't expire unless the peer disappears // This approach is used to limit the SRDI traffic. The key // point here is that SRDI is used to tell a peer that another // has a route to the destination it is looking for. The information // that SRDI cache is not so much the specific route info but rather // the fact that a peer has knowledge of a route to another peer // We don't want to update the SRDI cache on every route update. // The SRDI cache will be flushed when the peer disconnect from // the rendezvous. if (LOG.isEnabledFor(Level.DEBUG)) { LOG.debug("sending a router SRDI message add route " + id); } if (peer == null) { PeerID destPeer = srdi.getReplicaPeer(id.toString()); peer = destPeer; } // don't push anywhere if we do not have a replica // or we are trying to send the query to ourself if (!localPeerId.equals(peer)) { srdi.pushSrdi(peer, srdiMsg); } } catch (Exception e) { if (LOG.isEnabledFor(Level.WARN)) { LOG.warn("SRDI push failed", e); } } }
/** * issue a new route discovery resolver request * * @param peer the destination as a logical enpoint address */ protected void findRoute(EndpointAddress peer) { RouteAdvertisement myRoute = router.getMyLocalRoute(); // No need to pursue further if we haven't // initialize our own route as responding // peers are not going to be able to respond to us. if (myRoute == null) { if (LOG.isEnabledFor(Level.DEBUG)) { LOG.debug("Cannot issue a find route if we don't know our own route"); } return; } if (LOG.isEnabledFor(Level.DEBUG)) { LOG.debug("Find route for peer = " + peer); } try { // create a new RouteQuery message RouteQuery doc = null; // check if we have some bad route information // for that peer, in that case pass the bad hop count BadRoute badRoute; badRoute = (BadRoute) router.getBadRoute(peer); if (badRoute != null) { // ok we have a bad route // pass the bad hops info as part of the query if (LOG.isEnabledFor(Level.DEBUG)) { LOG.debug("findRoute sends query: known bad Hops" + badRoute.display()); } doc = new RouteQuery(router.addr2pid(peer), myRoute, badRoute.getHops()); } else { doc = new RouteQuery(router.addr2pid(peer), myRoute, null); } if (LOG.isEnabledFor(Level.DEBUG)) { LOG.debug("Sending query for peer : " + peer); } ResolverQuery query = new ResolverQuery( routerSName, credentialDoc, localPeerId.toString(), doc.toString(), qid++); // only run SRDI if we are a rendezvous if (group.isRendezvous()) { // check where to send the query via SRDI Vector results = null; if (srdiIndex != null) { // try to find a least 10 entries, will pick up one // randomly. This will protect against retry. It is // likely that a number of RDV will know about a route results = srdiIndex.query("route", "DstPID", router.addr2pid(peer).toString(), 10); if (results != null && results.size() > 0) { // use SRDI to send the query // remove any non rdv peers from the candidate list // and garbage collect the index in the process Vector clean = cleanupAnyEdges(query.getSrc(), results); if (clean.size() > 0) { // The purpose of incrementing the hopcount // when an SRDI index match is found (we got a // pointer to a rdv that should have the route) is to // restrict any further forwarding. The increment // count is only done when a matching SRDI index is // found. Not when the replica is selected as we // still need to forward the query. This restriction // is purposelly done to avoid too many longjumps // within a walk. query.incrementHopCount(); srdi.forwardQuery(clean, query, 1); if (LOG.isEnabledFor(Level.DEBUG)) { LOG.debug("found an srdi entry forwarding query to SRDI peer"); } return; } } else { // it is not in our cache, look for the replica peer // we need to send the query PeerID destPeer = srdi.getReplicaPeer(router.addr2pid(peer).toString()); if (destPeer != null && !destPeer.equals(localPeerId)) { // don't push anywhere if we do not have a replica // or we are trying to push to ourself if (LOG.isEnabledFor(Level.DEBUG)) { LOG.debug("processQuery srdiIndex DHT forward :" + destPeer); } srdi.forwardQuery(destPeer.toString(), query); return; } } } } // if we reach that point then we just use the resolver walk resolver = group.getResolverService(); if (resolver != null) { resolver.sendQuery(null, query); if (LOG.isEnabledFor(Level.DEBUG)) { LOG.debug("find route query sent"); } } else { if (LOG.isEnabledFor(Level.WARN)) { LOG.warn("cannot get the resolver service"); } } } catch (Exception ee) { if (LOG.isEnabledFor(Level.WARN)) { LOG.warn("Exception in findRoute", ee); } } }