// Ping a peer, log the time it took func (dht *IpfsDHT) Ping(p *peer.Peer, timeout time.Duration) error { // Thoughts: maybe this should accept an ID and do a peer lookup? u.DOut("Enter Ping.\n") pmes := Message{ID: swarm.GenerateMessageID(), Type: PBDHTMessage_PING} mes := swarm.NewMessage(p, pmes.ToProtobuf()) before := time.Now() responseChan := dht.listener.Listen(pmes.ID, 1, time.Minute) dht.netChan.Outgoing <- mes tout := time.After(timeout) select { case <-responseChan: roundtrip := time.Since(before) p.SetLatency(roundtrip) u.DOut("Ping took %s.\n", roundtrip.String()) return nil case <-tout: // Timed out, think about removing peer from network u.DOut("[%s] Ping peer [%s] timed out.", dht.self.ID.Pretty(), p.ID.Pretty()) dht.listener.Unlisten(pmes.ID) return u.ErrTimeout } }