Cleanup and speedup network convergence along with direct messaging for connect and solicit

client/rpc_client.go

@@ -316,6 +316,22 @@ func (r *rpcClient) Options() Options {
 	return r.opts
 }
 
+// hasProxy checks if we have proxy set in the environment
+func (r *rpcClient) hasProxy() bool {
+	// get proxy
+	if prx := os.Getenv("MICRO_PROXY"); len(prx) > 0 {
+		return true
+	}
+
+	// get proxy address
+	if prx := os.Getenv("MICRO_PROXY_ADDRESS"); len(prx) > 0 {
+		return true
+	}
+
+	return false
+}
+
+// next returns an iterator for the next nodes to call
 func (r *rpcClient) next(request Request, opts CallOptions) (selector.Next, error) {
 	service := request.Service()
 
@@ -431,10 +447,18 @@ func (r *rpcClient) Call(ctx context.Context, request Request, response interfac
 		return err
 	}
 
-	ch := make(chan error, callOpts.Retries+1)
+	// get the retries
+	retries := callOpts.Retries
+
+	// disable retries when using a proxy
+	if r.hasProxy() {
+		retries = 0
+	}
+
+	ch := make(chan error, retries+1)
 	var gerr error
 
-	for i := 0; i <= callOpts.Retries; i++ {
+	for i := 0; i <= retries; i++ {
 		go func(i int) {
 			ch <- call(i)
 		}(i)
@@ -514,10 +538,18 @@ func (r *rpcClient) Stream(ctx context.Context, request Request, opts ...CallOpt
 		err    error
 	}
 
-	ch := make(chan response, callOpts.Retries+1)
+	// get the retries
+	retries := callOpts.Retries
+
+	// disable retries when using a proxy
+	if r.hasProxy() {
+		retries = 0
+	}
+
+	ch := make(chan response, retries+1)
 	var grr error
 
-	for i := 0; i <= callOpts.Retries; i++ {
+	for i := 0; i <= retries; i++ {
 		go func(i int) {
 			s, err := call(i)
 			ch <- response{s, err}

client/rpc_codec.go

@@ -88,32 +88,24 @@ func (rwc *readWriteCloser) Close() error {
 }
 
 func getHeaders(m *codec.Message) {
-	get := func(hdr string) string {
+	set := func(v, hdr string) string {
-		if hd := m.Header[hdr]; len(hd) > 0 {
+		if len(v) > 0 {
-			return hd
+			return v
 		}
-		// old
+		return m.Header[hdr]
-		return m.Header["X-"+hdr]
 	}
 
 	// check error in header
-	if len(m.Error) == 0 {
+	m.Error = set(m.Error, "Micro-Error")
-		m.Error = get("Micro-Error")
-	}
 
 	// check endpoint in header
-	if len(m.Endpoint) == 0 {
+	m.Endpoint = set(m.Endpoint, "Micro-Endpoint")
-		m.Endpoint = get("Micro-Endpoint")
-	}
 
 	// check method in header
-	if len(m.Method) == 0 {
+	m.Method = set(m.Method, "Micro-Method")
-		m.Method = get("Micro-Method")
-	}
 
-	if len(m.Id) == 0 {
+	// set the request id
-		m.Id = get("Micro-Id")
+	m.Id = set(m.Id, "Micro-Id")
-	}
 }
 
 func setHeaders(m *codec.Message, stream string) {
@@ -122,7 +114,6 @@ func setHeaders(m *codec.Message, stream string) {
 			return
 		}
 		m.Header[hdr] = v
-		m.Header["X-"+hdr] = v
 	}
 
 	set("Micro-Id", m.Id)

network/default.go

@@ -71,9 +71,18 @@ type network struct {
 	connected bool
 	// closed closes the network
 	closed chan bool
-	// whether we've announced the first connect successfully
+	// whether we've discovered by the network
-	// and received back some sort of peer message
+	discovered chan bool
-	announced chan bool
+	// solicted checks whether routes were solicited by one node
+	solicited chan string
+}
+
+// message is network message
+type message struct {
+	// msg is transport message
+	msg *transport.Message
+	// session is tunnel session
+	session tunnel.Session
 }
 
 // newNetwork returns a new network node
@@ -149,14 +158,16 @@ func newNetwork(opts ...Option) Network {
 			address: peerAddress,
 			peers:   make(map[string]*node),
 		},
-		options:   options,
+		options:    options,
-		router:    options.Router,
+		router:     options.Router,
-		proxy:     options.Proxy,
+		proxy:      options.Proxy,
-		tunnel:    options.Tunnel,
+		tunnel:     options.Tunnel,
-		server:    server,
+		server:     server,
-		client:    client,
+		client:     client,
-		tunClient: make(map[string]transport.Client),
+		tunClient:  make(map[string]transport.Client),
-		peerLinks: make(map[string]tunnel.Link),
+		peerLinks:  make(map[string]tunnel.Link),
+		discovered: make(chan bool, 1),
+		solicited:  make(chan string, 1),
 	}
 
 	network.node.network = network
@@ -278,6 +289,14 @@ func (n *network) handleNetConn(s tunnel.Session, msg chan *message) {
 			continue
 		}
 
+		// check if peer is set
+		peer := m.Header["Micro-Peer"]
+
+		// check who the message is intended for
+		if len(peer) > 0 && peer != n.options.Id {
+			continue
+		}
+
 		select {
 		case msg <- &message{
 			msg:     m,
@@ -367,26 +386,33 @@ func (n *network) processNetChan(listener tunnel.Listener) {
 				// mark the time the message has been received
 				now := time.Now()
 				pbNetConnect := &pbNet.Connect{}
+
 				if err := proto.Unmarshal(m.msg.Body, pbNetConnect); err != nil {
 					log.Debugf("Network tunnel [%s] connect unmarshal error: %v", NetworkChannel, err)
 					continue
 				}
+
 				// don't process your own messages
 				if pbNetConnect.Node.Id == n.options.Id {
 					continue
 				}
+
 				log.Debugf("Network received connect message from: %s", pbNetConnect.Node.Id)
+
 				peer := &node{
 					id:       pbNetConnect.Node.Id,
 					address:  pbNetConnect.Node.Address,
 					peers:    make(map[string]*node),
 					lastSeen: now,
 				}
+
 				// update peer links
 				log.Tracef("Network updating peer link %s for peer: %s", m.session.Link(), pbNetConnect.Node.Address)
+
 				if err := n.updatePeerLinks(pbNetConnect.Node.Address, m.session.Link()); err != nil {
 					log.Debugf("Network failed updating peer links: %s", err)
 				}
+
 				// add peer to the list of node peers
 				if err := n.node.AddPeer(peer); err == ErrPeerExists {
 					log.Debugf("Network peer exists, refreshing: %s", peer.id)
@@ -394,50 +420,76 @@ func (n *network) processNetChan(listener tunnel.Listener) {
 					if err := n.RefreshPeer(peer.id, now); err != nil {
 						log.Debugf("Network failed refreshing peer %s: %v", peer.id, err)
 					}
-					continue
 				}
+
+				// we send the peer message because someone has sent connect
+				// and wants to know what's on the network. The faster we
+				// respond the faster we start to converge
+
 				// get node peers down to MaxDepth encoded in protobuf
 				msg := PeersToProto(n.node, MaxDepth)
+				node := pbNetConnect.Node.Id
+
 				// advertise yourself to the network
-				if err := n.sendMsg("peer", msg, NetworkChannel); err != nil {
+				if err := n.sendTo("peer", NetworkChannel, node, msg); err != nil {
 					log.Debugf("Network failed to advertise peers: %v", err)
 				}
+
 				// advertise all the routes when a new node has connected
 				if err := n.router.Solicit(); err != nil {
 					log.Debugf("Network failed to solicit routes: %s", err)
 				}
+
+				// specify that we're soliciting
+				select {
+				case n.solicited <- node:
+				default:
+					// don't block
+				}
 			case "peer":
 				// mark the time the message has been received
 				now := time.Now()
 				pbNetPeer := &pbNet.Peer{}
+
 				if err := proto.Unmarshal(m.msg.Body, pbNetPeer); err != nil {
 					log.Debugf("Network tunnel [%s] peer unmarshal error: %v", NetworkChannel, err)
 					continue
 				}
+
 				// don't process your own messages
 				if pbNetPeer.Node.Id == n.options.Id {
 					continue
 				}
+
 				log.Debugf("Network received peer message from: %s %s", pbNetPeer.Node.Id, pbNetPeer.Node.Address)
+
 				peer := &node{
 					id:       pbNetPeer.Node.Id,
 					address:  pbNetPeer.Node.Address,
 					peers:    make(map[string]*node),
 					lastSeen: now,
 				}
+
 				// update peer links
 				log.Tracef("Network updating peer link %s for peer: %s", m.session.Link(), pbNetPeer.Node.Address)
+
 				if err := n.updatePeerLinks(pbNetPeer.Node.Address, m.session.Link()); err != nil {
 					log.Debugf("Network failed updating peer links: %s", err)
 				}
+
 				if err := n.node.AddPeer(peer); err == nil {
 					// send a solicit message when discovering new peer
 					msg := &pbRtr.Solicit{
 						Id: n.options.Id,
 					}
-					if err := n.sendMsg("solicit", msg, ControlChannel); err != nil {
+
+					node := pbNetPeer.Node.Id
+
+					// only solicit this peer
+					if err := n.sendTo("solicit", ControlChannel, node, msg); err != nil {
 						log.Debugf("Network failed to send solicit message: %s", err)
 					}
+
 					continue
 					// we're expecting any error to be ErrPeerExists
 				} else if err != ErrPeerExists {
@@ -446,6 +498,7 @@ func (n *network) processNetChan(listener tunnel.Listener) {
 				}
 
 				log.Debugf("Network peer exists, refreshing: %s", pbNetPeer.Node.Id)
+
 				// update lastSeen time for the peer
 				if err := n.RefreshPeer(pbNetPeer.Node.Id, now); err != nil {
 					log.Debugf("Network failed refreshing peer %s: %v", pbNetPeer.Node.Id, err)
@@ -458,12 +511,12 @@ func (n *network) processNetChan(listener tunnel.Listener) {
 					log.Debugf("Network failed to update peers: %v", err)
 				}
 
-				// check if we announced and were discovered
+				// tell the connect loop that we've been discovered
+				// so it stops sending connect messages out
 				select {
-				case <-n.announced:
+				case n.discovered <- true:
-					// we've sent the connect and received this response
 				default:
-					close(n.announced)
+					// don't block here
 				}
 			case "close":
 				pbNetClose := &pbNet.Close{}
@@ -471,22 +524,28 @@ func (n *network) processNetChan(listener tunnel.Listener) {
 					log.Debugf("Network tunnel [%s] close unmarshal error: %v", NetworkChannel, err)
 					continue
 				}
+
 				// don't process your own messages
 				if pbNetClose.Node.Id == n.options.Id {
 					continue
 				}
+
 				log.Debugf("Network received close message from: %s", pbNetClose.Node.Id)
+
 				peer := &node{
 					id:      pbNetClose.Node.Id,
 					address: pbNetClose.Node.Address,
 				}
+
 				if err := n.DeletePeerNode(peer.id); err != nil {
 					log.Debugf("Network failed to delete node %s routes: %v", peer.id, err)
 				}
+
 				if err := n.prunePeerRoutes(peer); err != nil {
 					log.Debugf("Network failed pruning peer %s routes: %v", peer.id, err)
 				}
-				// deelete peer from the peerLinks
+
+				// delete peer from the peerLinks
 				n.Lock()
 				delete(n.peerLinks, pbNetClose.Node.Address)
 				n.Unlock()
@@ -497,57 +556,6 @@ func (n *network) processNetChan(listener tunnel.Listener) {
 	}
 }
 
-// sendMsg sends a message to the tunnel channel
-func (n *network) sendMsg(method string, msg proto.Message, channel string) error {
-	body, err := proto.Marshal(msg)
-	if err != nil {
-		return err
-	}
-	// create transport message and chuck it down the pipe
-	m := transport.Message{
-		Header: map[string]string{
-			"Micro-Method": method,
-		},
-		Body: body,
-	}
-
-	// check if the channel client is initialized
-	n.RLock()
-	client, ok := n.tunClient[channel]
-	if !ok || client == nil {
-		n.RUnlock()
-		return ErrClientNotFound
-	}
-	n.RUnlock()
-
-	log.Debugf("Network sending %s message from: %s", method, n.options.Id)
-	if err := client.Send(&m); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-// announce announces node peers to the network
-func (n *network) announce(client transport.Client) {
-	announce := time.NewTicker(AnnounceTime)
-	defer announce.Stop()
-
-	for {
-		select {
-		case <-n.closed:
-			return
-		case <-announce.C:
-			msg := PeersToProto(n.node, MaxDepth)
-			// advertise yourself to the network
-			if err := n.sendMsg("peer", msg, NetworkChannel); err != nil {
-				log.Debugf("Network failed to advertise peers: %v", err)
-				continue
-			}
-		}
-	}
-}
-
 // pruneRoutes prunes routes return by given query
 func (n *network) pruneRoutes(q ...router.QueryOption) error {
 	routes, err := n.router.Table().Query(q...)
@@ -585,9 +593,12 @@ func (n *network) prunePeerRoutes(peer *node) error {
 	return nil
 }
 
-// prune deltes node peers that have not been seen for longer than PruneTime seconds
+// manage the process of announcing to peers and prune any peer nodes that have not been
-// prune also removes all the routes either originated by or routable by the stale nodes
+// seen for a period of time. Also removes all the routes either originated by or routable
-func (n *network) prune() {
+//by the stale nodes
+func (n *network) manage() {
+	announce := time.NewTicker(AnnounceTime)
+	defer announce.Stop()
 	prune := time.NewTicker(PruneTime)
 	defer prune.Stop()
 
@@ -595,8 +606,14 @@ func (n *network) prune() {
 		select {
 		case <-n.closed:
 			return
+		case <-announce.C:
+			msg := PeersToProto(n.node, MaxDepth)
+			// advertise yourself to the network
+			if err := n.sendMsg("peer", NetworkChannel, msg); err != nil {
+				log.Debugf("Network failed to advertise peers: %v", err)
+			}
 		case <-prune.C:
-			pruned := n.PruneStalePeerNodes(PruneTime)
+			pruned := n.PruneStalePeers(PruneTime)
 			for id, peer := range pruned {
 				log.Debugf("Network peer exceeded prune time: %s", id)
 				n.Lock()
@@ -606,29 +623,90 @@ func (n *network) prune() {
 					log.Debugf("Network failed pruning peer %s routes: %v", id, err)
 				}
 			}
+
 			// get a list of all routes
 			routes, err := n.options.Router.Table().List()
 			if err != nil {
 				log.Debugf("Network failed listing routes when pruning peers: %v", err)
 				continue
 			}
+
 			// collect all the router IDs in the routing table
 			routers := make(map[string]bool)
+
 			for _, route := range routes {
-				if _, ok := routers[route.Router]; !ok {
+				// check if its been processed
-					routers[route.Router] = true
+				if _, ok := routers[route.Router]; ok {
-					// if the router is NOT in our peer graph, delete all routes originated by it
+					continue
-					if peerNode := n.node.GetPeerNode(route.Router); peerNode == nil {
+				}
-						if err := n.pruneRoutes(router.QueryRouter(route.Router)); err != nil {
+
-							log.Debugf("Network failed deleting routes by %s: %v", route.Router, err)
+				// mark as processed
-						}
+				routers[route.Router] = true
-					}
+
+				// if the router is NOT in our peer graph, delete all routes originated by it
+				if peer := n.node.GetPeerNode(route.Router); peer != nil {
+					continue
+				}
+
+				if err := n.pruneRoutes(router.QueryRouter(route.Router)); err != nil {
+					log.Debugf("Network failed deleting routes by %s: %v", route.Router, err)
 				}
 			}
 		}
 	}
 }
 
+// sendTo sends a message to a specific node as a one off.
+// we need this because when links die, we have no discovery info,
+// and sending to an existing multicast link doesn't immediately work
+func (n *network) sendTo(method, channel, peer string, msg proto.Message) error {
+	body, err := proto.Marshal(msg)
+	if err != nil {
+		return err
+	}
+	c, err := n.tunnel.Dial(channel, tunnel.DialMode(tunnel.Multicast))
+	if err != nil {
+		return err
+	}
+	defer c.Close()
+
+	log.Debugf("Network sending %s message from: %s to %s", method, n.options.Id, peer)
+
+	return c.Send(&transport.Message{
+		Header: map[string]string{
+			"Micro-Method": method,
+			"Micro-Peer":   peer,
+		},
+		Body: body,
+	})
+}
+
+// sendMsg sends a message to the tunnel channel
+func (n *network) sendMsg(method, channel string, msg proto.Message) error {
+	body, err := proto.Marshal(msg)
+	if err != nil {
+		return err
+	}
+
+	// check if the channel client is initialized
+	n.RLock()
+	client, ok := n.tunClient[channel]
+	if !ok || client == nil {
+		n.RUnlock()
+		return ErrClientNotFound
+	}
+	n.RUnlock()
+
+	log.Debugf("Network sending %s message from: %s", method, n.options.Id)
+
+	return client.Send(&transport.Message{
+		Header: map[string]string{
+			"Micro-Method": method,
+		},
+		Body: body,
+	})
+}
+
 // handleCtrlConn handles ControlChannel connections
 func (n *network) handleCtrlConn(s tunnel.Session, msg chan *message) {
 	for {
@@ -642,6 +720,14 @@ func (n *network) handleCtrlConn(s tunnel.Session, msg chan *message) {
 			continue
 		}
 
+		// check if peer is set
+		peer := m.Header["Micro-Peer"]
+
+		// check who the message is intended for
+		if len(peer) > 0 && peer != n.options.Id {
+			continue
+		}
+
 		select {
 		case msg <- &message{
 			msg:     m,
@@ -770,15 +856,19 @@ func (n *network) processCtrlChan(listener tunnel.Listener) {
 			switch m.msg.Header["Micro-Method"] {
 			case "advert":
 				pbRtrAdvert := &pbRtr.Advert{}
+
 				if err := proto.Unmarshal(m.msg.Body, pbRtrAdvert); err != nil {
 					log.Debugf("Network fail to unmarshal advert message: %v", err)
 					continue
 				}
+
 				// don't process your own messages
 				if pbRtrAdvert.Id == n.options.Id {
 					continue
 				}
+
 				log.Debugf("Network received advert message from: %s", pbRtrAdvert.Id)
+
 				// loookup advertising node in our peer topology
 				advertNode := n.node.GetPeerNode(pbRtrAdvert.Id)
 				if advertNode == nil {
@@ -788,6 +878,7 @@ func (n *network) processCtrlChan(listener tunnel.Listener) {
 				}
 
 				var events []*router.Event
+
 				for _, event := range pbRtrAdvert.Events {
 					// we know the advertising node is not the origin of the route
 					if pbRtrAdvert.Id != event.Route.Router {
@@ -798,6 +889,7 @@ func (n *network) processCtrlChan(listener tunnel.Listener) {
 							continue
 						}
 					}
+
 					route := router.Route{
 						Service: event.Route.Service,
 						Address: event.Route.Address,
@@ -807,6 +899,7 @@ func (n *network) processCtrlChan(listener tunnel.Listener) {
 						Link:    event.Route.Link,
 						Metric:  event.Route.Metric,
 					}
+
 					// calculate route metric and add to the advertised metric
 					// we need to make sure we do not overflow math.MaxInt64
 					metric := n.getRouteMetric(event.Route.Router, event.Route.Gateway, event.Route.Link)
@@ -829,11 +922,13 @@ func (n *network) processCtrlChan(listener tunnel.Listener) {
 					}
 					events = append(events, e)
 				}
+
 				// if no events are eligible for processing continue
 				if len(events) == 0 {
 					log.Tracef("Network no events to be processed by router: %s", n.options.Id)
 					continue
 				}
+
 				// create an advert and process it
 				advert := &router.Advert{
 					Id:        pbRtrAdvert.Id,
@@ -853,16 +948,27 @@ func (n *network) processCtrlChan(listener tunnel.Listener) {
 					log.Debugf("Network fail to unmarshal solicit message: %v", err)
 					continue
 				}
+
 				log.Debugf("Network received solicit message from: %s", pbRtrSolicit.Id)
+
 				// ignore solicitation when requested by you
 				if pbRtrSolicit.Id == n.options.Id {
 					continue
 				}
+
 				log.Debugf("Network router flushing routes for: %s", pbRtrSolicit.Id)
+
 				// advertise all the routes when a new node has connected
 				if err := n.router.Solicit(); err != nil {
 					log.Debugf("Network failed to solicit routes: %s", err)
 				}
+
+				// specify that someone solicited the route
+				select {
+				case n.solicited <- pbRtrSolicit.Id:
+				default:
+					// don't block
+				}
 			}
 		case <-n.closed:
 			return
@@ -879,6 +985,7 @@ func (n *network) advertise(advertChan <-chan *router.Advert) {
 		case advert := <-advertChan:
 			// create a proto advert
 			var events []*pbRtr.Event
+
 			for _, event := range advert.Events {
 				// the routes service address
 				address := event.Route.Address
@@ -912,16 +1019,33 @@ func (n *network) advertise(advertChan <-chan *router.Advert) {
 				}
 				events = append(events, e)
 			}
+
 			msg := &pbRtr.Advert{
 				Id:        advert.Id,
 				Type:      pbRtr.AdvertType(advert.Type),
 				Timestamp: advert.Timestamp.UnixNano(),
 				Events:    events,
 			}
-			if err := n.sendMsg("advert", msg, ControlChannel); err != nil {
+
-				log.Debugf("Network failed to advertise routes: %v", err)
+			// send the advert to all on the control channel
+			// since its not a solicitation
+			if advert.Type != router.Solicitation {
+				if err := n.sendMsg("advert", ControlChannel, msg); err != nil {
+					log.Debugf("Network failed to advertise routes: %v", err)
+				}
 				continue
 			}
+
+			// it's a solication, someone asked for it
+			// so we're going to pick off the node and send it
+			select {
+			case node := <-n.solicited:
+				// someone requested the route
+				n.sendTo("advert", ControlChannel, node, msg)
+			default:
+				// send to all since we can't get anything
+				n.sendMsg("advert", ControlChannel, msg)
+			}
 		case <-n.closed:
 			return
 		}
@@ -939,41 +1063,87 @@ func (n *network) sendConnect() {
 			Address: n.node.address,
 		},
 	}
-	if err := n.sendMsg("connect", msg, NetworkChannel); err != nil {
+
+	if err := n.sendMsg("connect", NetworkChannel, msg); err != nil {
 		log.Debugf("Network failed to send connect message: %s", err)
 	}
 }
 
-// connect will wait for a link to be established
+// connect will wait for a link to be established and send the connect
+// message. We're trying to ensure convergence pretty quickly. So we want
+// to hear back. In the case we become completely disconnected we'll
+// connect again once a new link is established
 func (n *network) connect() {
-	// wait for connected state
+	// discovered lets us know what we received a peer message back
-	var connected bool
+	var discovered bool
+	var attempts int
+
+	// our advertise address
+	loopback := n.server.Options().Advertise
+	// actual address
+	address := n.tunnel.Address()
 
 	for {
-		// check the links
+		// connected is used to define if the link is connected
+		var connected bool
+
+		// check the links state
 		for _, link := range n.tunnel.Links() {
+			// skip loopback
+			if link.Loopback() {
+				continue
+			}
+
+			// if remote is ourselves
+			switch link.Remote() {
+			case loopback, address:
+				continue
+			}
+
 			if link.State() == "connected" {
 				connected = true
 				break
 			}
 		}
 
-		// if we're not conencted wait
+		// if we're not connected wait
 		if !connected {
+			// reset discovered
+			discovered = false
+			// sleep for a second
 			time.Sleep(time.Second)
+			// now try again
 			continue
 		}
 
-		// send the connect message
+		// we're connected but are we discovered?
-		n.sendConnect()
+		if !discovered {
+			// recreate the clients because all the tunnel links are gone
+			// so we haven't send discovery beneath
+			if err := n.createClients(); err != nil {
+				log.Debugf("Failed to recreate network/control clients: %v", err)
+				continue
+			}
 
-		// check the announce channel
+			// send the connect message
+			n.sendConnect()
+		}
+
+		// check if we've been discovered
 		select {
-		case <-n.announced:
+		case <-n.discovered:
+			discovered = true
+			attempts = 0
+		case <-n.closed:
 			return
-		default:
+		case <-time.After(time.Second + backoff.Do(attempts)):
-			time.Sleep(time.Second)
+			// we have to try again
-			// we have to go again
+			attempts++
+
+			// reset attempts 5 == ~2mins
+			if attempts > 5 {
+				attempts = 0
+			}
 		}
 	}
 }
@@ -982,18 +1152,18 @@ func (n *network) connect() {
 func (n *network) Connect() error {
 	n.Lock()
 
-	// try to resolve network nodes
-	nodes, err := n.resolveNodes()
-	if err != nil {
-		log.Debugf("Network failed to resolve nodes: %v", err)
-	}
-
 	// connect network tunnel
 	if err := n.tunnel.Connect(); err != nil {
 		n.Unlock()
 		return err
 	}
 
+	// try to resolve network nodes
+	nodes, err := n.resolveNodes()
+	if err != nil {
+		log.Debugf("Network failed to resolve nodes: %v", err)
+	}
+
 	// initialize the tunnel to resolved nodes
 	n.tunnel.Init(
 		tunnel.Nodes(nodes...),
@@ -1048,8 +1218,6 @@ func (n *network) Connect() error {
 
 	// create closed channel
 	n.closed = make(chan bool)
-	// create new announced channel
-	n.announced = make(chan bool)
 
 	// start the router
 	if err := n.options.Router.Start(); err != nil {
@@ -1073,16 +1241,14 @@ func (n *network) Connect() error {
 
 	// send connect after there's a link established
 	go n.connect()
-	// go resolving network nodes
+	// resolve network nodes and re-init the tunnel
 	go n.resolve()
-	// broadcast peers
+	// broadcast announcements and prune stale nodes
-	go n.announce(netClient)
+	go n.manage()
-	// prune stale nodes
-	go n.prune()
-	// listen to network messages
-	go n.processNetChan(netListener)
 	// advertise service routes
 	go n.advertise(advertChan)
+	// listen to network messages
+	go n.processNetChan(netListener)
 	// accept and process routes
 	go n.processCtrlChan(ctrlListener)
 
@@ -1112,6 +1278,40 @@ func (n *network) close() error {
 	return nil
 }
 
+// createClients is used to create new clients in the event we lose all the tunnels
+func (n *network) createClients() error {
+	// dial into ControlChannel to send route adverts
+	ctrlClient, err := n.tunnel.Dial(ControlChannel, tunnel.DialMode(tunnel.Multicast))
+	if err != nil {
+		return err
+	}
+
+	// dial into NetworkChannel to send network messages
+	netClient, err := n.tunnel.Dial(NetworkChannel, tunnel.DialMode(tunnel.Multicast))
+	if err != nil {
+		return err
+	}
+
+	n.Lock()
+	defer n.Unlock()
+
+	// set the control client
+	c, ok := n.tunClient[ControlChannel]
+	if ok {
+		c.Close()
+	}
+	n.tunClient[ControlChannel] = ctrlClient
+
+	// set the network client
+	c, ok = n.tunClient[NetworkChannel]
+	if ok {
+		c.Close()
+	}
+	n.tunClient[NetworkChannel] = netClient
+
+	return nil
+}
+
 // Close closes network connection
 func (n *network) Close() error {
 	n.Lock()
@@ -1140,7 +1340,7 @@ func (n *network) Close() error {
 				Address: n.node.address,
 			},
 		}
-		if err := n.sendMsg("close", msg, NetworkChannel); err != nil {
+		if err := n.sendMsg("close", NetworkChannel, msg); err != nil {
 			log.Debugf("Network failed to send close message: %s", err)
 		}
 	}

network/network.go

@@ -56,14 +56,6 @@ type Network interface {
 	Server() server.Server
 }
 
-// message is network message
-type message struct {
-	// msg is transport message
-	msg *transport.Message
-	// session is tunnel session
-	session tunnel.Session
-}
-
 // NewNetwork returns a new network interface
 func NewNetwork(opts ...Option) Network {
 	return newNetwork(opts...)

network/node.go

@@ -216,7 +216,7 @@ func (n *node) DeletePeerNode(id string) error {
 
 // PruneStalePeerNodes prune the peers that have not been seen for longer than given time
 // It returns a map of the the nodes that got pruned
-func (n *node) PruneStalePeerNodes(pruneTime time.Duration) map[string]*node {
+func (n *node) PruneStalePeers(pruneTime time.Duration) map[string]*node {
 	n.Lock()
 	defer n.Unlock()
 

network/node_test.go

@@ -225,7 +225,7 @@ func TestPruneStalePeerNodes(t *testing.T) {
 	time.Sleep(pruneTime)
 
 	// should delete all nodes besides node
-	pruned := node.PruneStalePeerNodes(pruneTime)
+	pruned := node.PruneStalePeers(pruneTime)
 
 	if len(pruned) != len(nodes)-1 {
 		t.Errorf("Expected pruned node count: %d, got: %d", len(nodes)-1, len(pruned))

proxy/mucp/mucp.go

@@ -83,7 +83,8 @@ func readLoop(r server.Request, s client.Stream) error {
 
 // toNodes returns a list of node addresses from given routes
 func toNodes(routes []router.Route) []string {
-	nodes := make([]string, len(routes))
+	nodes := make([]string, 0, len(routes))
+
 	for _, node := range routes {
 		address := node.Address
 		if len(node.Gateway) > 0 {
@@ -91,11 +92,13 @@ func toNodes(routes []router.Route) []string {
 		}
 		nodes = append(nodes, address)
 	}
+
 	return nodes
 }
 
 func toSlice(r map[uint64]router.Route) []router.Route {
 	routes := make([]router.Route, 0, len(r))
+
 	for _, v := range r {
 		routes = append(routes, v)
 	}
@@ -161,6 +164,8 @@ func (p *Proxy) filterRoutes(ctx context.Context, routes []router.Route) []route
 		filteredRoutes = append(filteredRoutes, route)
 	}
 
+	log.Tracef("Proxy filtered routes %+v vs %+v\n", routes, filteredRoutes)
+
 	return filteredRoutes
 }
 
@@ -225,13 +230,15 @@ func (p *Proxy) cacheRoutes(service string) ([]router.Route, error) {
 // refreshMetrics will refresh any metrics for our local cached routes.
 // we may not receive new watch events for these as they change.
 func (p *Proxy) refreshMetrics() {
-	services := make([]string, 0, len(p.Routes))
-
 	// get a list of services to update
 	p.RLock()
+
+	services := make([]string, 0, len(p.Routes))
+
 	for service := range p.Routes {
 		services = append(services, service)
 	}
+
 	p.RUnlock()
 
 	// get and cache the routes for the service
@@ -246,6 +253,8 @@ func (p *Proxy) manageRoutes(route router.Route, action string) error {
 	p.Lock()
 	defer p.Unlock()
 
+	log.Tracef("Proxy taking route action %v %+v\n", action, route)
+
 	switch action {
 	case "create", "update":
 		if _, ok := p.Routes[route.Service]; !ok {
@@ -253,7 +262,12 @@ func (p *Proxy) manageRoutes(route router.Route, action string) error {
 		}
 		p.Routes[route.Service][route.Hash()] = route
 	case "delete":
+		// delete that specific route
 		delete(p.Routes[route.Service], route.Hash())
+		// clean up the cache entirely
+		if len(p.Routes[route.Service]) == 0 {
+			delete(p.Routes, route.Service)
+		}
 	default:
 		return fmt.Errorf("unknown action: %s", action)
 	}
@@ -288,7 +302,7 @@ func (p *Proxy) ProcessMessage(ctx context.Context, msg server.Message) error {
 	// TODO: check that we're not broadcast storming by sending to the same topic
 	// that we're actually subscribed to
 
-	log.Tracef("Received message for %s", msg.Topic())
+	log.Tracef("Proxy received message for %s", msg.Topic())
 
 	var errors []string
 
@@ -329,7 +343,7 @@ func (p *Proxy) ServeRequest(ctx context.Context, req server.Request, rsp server
 		return errors.BadRequest("go.micro.proxy", "service name is blank")
 	}
 
-	log.Tracef("Received request for %s", service)
+	log.Tracef("Proxy received request for %s", service)
 
 	// are we network routing or local routing
 	if len(p.Links) == 0 {
@@ -363,15 +377,17 @@ func (p *Proxy) ServeRequest(ctx context.Context, req server.Request, rsp server
 	}
 
 	//nolint:prealloc
-	var opts []client.CallOption
+	opts := []client.CallOption{
-
+		// set strategy to round robin
-	// set strategy to round robin
+		client.WithSelectOption(selector.WithStrategy(selector.RoundRobin)),
-	opts = append(opts, client.WithSelectOption(selector.WithStrategy(selector.RoundRobin)))
+	}
 
 	// if the address is already set just serve it
 	// TODO: figure it out if we should know to pick a link
 	if len(addresses) > 0 {
-		opts = append(opts, client.WithAddress(addresses...))
+		opts = append(opts,
+			client.WithAddress(addresses...),
+		)
 
 		// serve the normal way
 		return p.serveRequest(ctx, p.Client, service, endpoint, req, rsp, opts...)
@@ -387,10 +403,16 @@ func (p *Proxy) ServeRequest(ctx context.Context, req server.Request, rsp server
 			opts = append(opts, client.WithAddress(addresses...))
 		}
 
+		log.Tracef("Proxy calling %+v\n", addresses)
 		// serve the normal way
 		return p.serveRequest(ctx, p.Client, service, endpoint, req, rsp, opts...)
 	}
 
+	// we're assuming we need routes to operate on
+	if len(routes) == 0 {
+		return errors.InternalServerError("go.micro.proxy", "route not found")
+	}
+
 	var gerr error
 
 	// we're routing globally with multiple links
@@ -404,11 +426,16 @@ func (p *Proxy) ServeRequest(ctx context.Context, req server.Request, rsp server
 			continue
 		}
 
-		log.Debugf("Proxy using route %+v\n", route)
+		log.Tracef("Proxy using route %+v\n", route)
 
 		// set the address to call
 		addresses := toNodes([]router.Route{route})
-		opts = append(opts, client.WithAddress(addresses...))
+		// set the address in the options
+		// disable retries since its one route processing
+		opts = append(opts,
+			client.WithAddress(addresses...),
+			client.WithRetries(0),
+		)
 
 		// do the request with the link
 		gerr = p.serveRequest(ctx, link, service, endpoint, req, rsp, opts...)
@@ -558,7 +585,9 @@ func NewProxy(opts ...options.Option) proxy.Proxy {
 	}()
 
 	go func() {
-		t := time.NewTicker(time.Minute)
+		// TODO: speed up refreshing of metrics
+		// without this ticking effort e.g stream
+		t := time.NewTicker(time.Second * 10)
 		defer t.Stop()
 
 		// we must refresh route metrics since they do not trigger new events

router/default.go

@@ -799,7 +799,8 @@ func (r *router) flushRouteEvents(evType EventType) ([]*Event, error) {
 
 	// build a list of events to advertise
 	events := make([]*Event, len(bestRoutes))
-	i := 0
+	var i int
+
 	for _, route := range bestRoutes {
 		event := &Event{
 			Type:      evType,
@@ -823,9 +824,10 @@ func (r *router) Solicit() error {
 
 	// advertise the routes
 	r.advertWg.Add(1)
+
 	go func() {
-		defer r.advertWg.Done()
+		r.publishAdvert(Solicitation, events)
-		r.publishAdvert(RouteUpdate, events)
+		r.advertWg.Done()
 	}()
 
 	return nil

router/router.go

@@ -111,6 +111,8 @@ const (
 	Announce AdvertType = iota
 	// RouteUpdate advertises route updates
 	RouteUpdate
+	// Solicitation indicates routes were solicited
+	Solicitation
 )
 
 // String returns human readable advertisement type
@@ -120,6 +122,8 @@ func (t AdvertType) String() string {
 		return "announce"
 	case RouteUpdate:
 		return "update"
+	case Solicitation:
+		return "solicitation"
 	default:
 		return "unknown"
 	}

server/rpc_codec.go

@@ -86,24 +86,18 @@ func getHeader(hdr string, md map[string]string) string {
 }
 
 func getHeaders(m *codec.Message) {
-	get := func(hdr, v string) string {
+	set := func(v, hdr string) string {
 		if len(v) > 0 {
 			return v
 		}
-
+		return m.Header[hdr]
-		if hd := m.Header[hdr]; len(hd) > 0 {
-			return hd
-		}
-
-		// old
-		return m.Header["X-"+hdr]
 	}
 
-	m.Id = get("Micro-Id", m.Id)
+	m.Id = set(m.Id, "Micro-Id")
-	m.Error = get("Micro-Error", m.Error)
+	m.Error = set(m.Error, "Micro-Error")
-	m.Endpoint = get("Micro-Endpoint", m.Endpoint)
+	m.Endpoint = set(m.Endpoint, "Micro-Endpoint")
-	m.Method = get("Micro-Method", m.Method)
+	m.Method = set(m.Method, "Micro-Method")
-	m.Target = get("Micro-Service", m.Target)
+	m.Target = set(m.Target, "Micro-Service")
 
 	// TODO: remove this cruft
 	if len(m.Endpoint) == 0 {
@@ -321,7 +315,6 @@ func (c *rpcCodec) Write(r *codec.Message, b interface{}) error {
 
 		// write an error if it failed
 		m.Error = errors.Wrapf(err, "Unable to encode body").Error()
-		m.Header["X-Micro-Error"] = m.Error
 		m.Header["Micro-Error"] = m.Error
 		// no body to write
 		if err := c.codec.Write(m, nil); err != nil {

server/rpc_server.go

@@ -549,6 +549,7 @@ func (s *rpcServer) Register() error {
 	node.Metadata["protocol"] = "mucp"
 
 	s.RLock()
+
 	// Maps are ordered randomly, sort the keys for consistency
 	var handlerList []string
 	for n, e := range s.handlers {
@@ -557,6 +558,7 @@ func (s *rpcServer) Register() error {
 			handlerList = append(handlerList, n)
 		}
 	}
+
 	sort.Strings(handlerList)
 
 	var subscriberList []Subscriber
@@ -566,18 +568,20 @@ func (s *rpcServer) Register() error {
 			subscriberList = append(subscriberList, e)
 		}
 	}
+
 	sort.Slice(subscriberList, func(i, j int) bool {
 		return subscriberList[i].Topic() > subscriberList[j].Topic()
 	})
 
 	endpoints := make([]*registry.Endpoint, 0, len(handlerList)+len(subscriberList))
+
 	for _, n := range handlerList {
 		endpoints = append(endpoints, s.handlers[n].Endpoints()...)
 	}
+
 	for _, e := range subscriberList {
 		endpoints = append(endpoints, e.Endpoints()...)
 	}
-	s.RUnlock()
 
 	service := &registry.Service{
 		Name:      config.Name,
@@ -586,9 +590,10 @@ func (s *rpcServer) Register() error {
 		Endpoints: endpoints,
 	}
 
-	s.Lock()
+	// get registered value
 	registered := s.registered
-	s.Unlock()
+
+	s.RUnlock()
 
 	if !registered {
 		log.Logf("Registry [%s] Registering node: %s", config.Registry.String(), node.Id)
@@ -610,6 +615,8 @@ func (s *rpcServer) Register() error {
 	defer s.Unlock()
 
 	s.registered = true
+	// set what we're advertising
+	s.opts.Advertise = addr
 
 	// subscribe to the topic with own name
 	sub, err := s.opts.Broker.Subscribe(config.Name, s.HandleEvent)

service.go

@@ -9,9 +9,9 @@ import (
 
 	"github.com/micro/go-micro/client"
 	"github.com/micro/go-micro/config/cmd"
-	"github.com/micro/go-micro/debug/service/handler"
 	"github.com/micro/go-micro/debug/profile"
 	"github.com/micro/go-micro/debug/profile/pprof"
+	"github.com/micro/go-micro/debug/service/handler"
 	"github.com/micro/go-micro/plugin"
 	"github.com/micro/go-micro/server"
 	"github.com/micro/go-micro/util/log"

tunnel/default.go

@@ -327,6 +327,7 @@ func (t *tun) process() {
 				// and the message is being sent outbound via
 				// a dialled connection don't use this link
 				if loopback && msg.outbound {
+					log.Tracef("Link for node %s is loopback", node)
 					err = errors.New("link is loopback")
 					continue
 				}
@@ -334,6 +335,7 @@ func (t *tun) process() {
 				// if the message was being returned by the loopback listener
 				// send it back up the loopback link only
 				if msg.loopback && !loopback {
+					log.Tracef("Link for message %s is loopback", node)
 					err = errors.New("link is not loopback")
 					continue
 				}
@@ -363,7 +365,7 @@ func (t *tun) process() {
 			// send the message
 			for _, link := range sendTo {
 				// send the message via the current link
-				log.Tracef("Sending %+v to %s", newMsg.Header, link.Remote())
+				log.Tracef("Tunnel sending %+v to %s", newMsg.Header, link.Remote())
 
 				if errr := link.Send(newMsg); errr != nil {
 					log.Debugf("Tunnel error sending %+v to %s: %v", newMsg.Header, link.Remote(), errr)
@@ -502,6 +504,7 @@ func (t *tun) listen(link *link) {
 			// nothing more to do
 			continue
 		case "close":
+			log.Debugf("Tunnel link %s received close message", link.Remote())
 			// if there is no channel then we close the link
 			// as its a signal from the other side to close the connection
 			if len(channel) == 0 {
@@ -555,9 +558,11 @@ func (t *tun) listen(link *link) {
 		// a continued session
 		case "session":
 			// process message
-			log.Tracef("Received %+v from %s", msg.Header, link.Remote())
+			log.Tracef("Tunnel received %+v from %s", msg.Header, link.Remote())
 		// an announcement of a channel listener
 		case "announce":
+			log.Tracef("Tunnel received %+v from %s", msg.Header, link.Remote())
+
 			// process the announcement
 			channels := strings.Split(channel, ",")
 
@@ -629,7 +634,7 @@ func (t *tun) listen(link *link) {
 			s, exists = t.getSession(channel, "listener")
 		// only return accept to the session
 		case mtype == "accept":
-			log.Debugf("Received accept message for channel: %s session: %s", channel, sessionId)
+			log.Debugf("Tunnel received accept message for channel: %s session: %s", channel, sessionId)
 			s, exists = t.getSession(channel, sessionId)
 			if exists && s.accepted {
 				continue
@@ -649,7 +654,7 @@ func (t *tun) listen(link *link) {
 
 		// bail if no session or listener has been found
 		if !exists {
-			log.Debugf("Tunnel skipping no channel: %s session: %s exists", channel, sessionId)
+			log.Tracef("Tunnel skipping no channel: %s session: %s exists", channel, sessionId)
 			// drop it, we don't care about
 			// messages we don't know about
 			continue
@@ -665,7 +670,7 @@ func (t *tun) listen(link *link) {
 			// otherwise process
 		}
 
-		log.Debugf("Tunnel using channel: %s session: %s type: %s", s.channel, s.session, mtype)
+		log.Tracef("Tunnel using channel: %s session: %s type: %s", s.channel, s.session, mtype)
 
 		// construct a new transport message
 		tmsg := &transport.Message{
@@ -740,7 +745,7 @@ func (t *tun) keepalive(link *link) {
 					"Micro-Tunnel-Id": t.id,
 				},
 			}); err != nil {
-				log.Debugf("Error sending keepalive to link %v: %v", link.Remote(), err)
+				log.Debugf("Tunnel error sending keepalive to link %v: %v", link.Remote(), err)
 				t.delLink(link.Remote())
 				return
 			}

tunnel/link.go

@@ -2,6 +2,7 @@ package tunnel
 
 import (
 	"bytes"
+	"errors"
 	"io"
 	"sync"
 	"time"
@@ -14,7 +15,11 @@ import (
 type link struct {
 	transport.Socket
 
+	// transport to use for connections
+	transport transport.Transport
+
 	sync.RWMutex
+
 	// stops the link
 	closed chan bool
 	// link state channel for testing link
@@ -65,6 +70,8 @@ var (
 	linkRequest = []byte{0, 0, 0, 0}
 	// the 4 byte 1 filled packet sent to determine link state
 	linkResponse = []byte{1, 1, 1, 1}
+
+	ErrLinkConnectTimeout = errors.New("link connect timeout")
 )
 
 func newLink(s transport.Socket) *link {
@@ -72,8 +79,8 @@ func newLink(s transport.Socket) *link {
 		Socket:        s,
 		id:            uuid.New().String(),
 		lastKeepAlive: time.Now(),
-		channels:      make(map[string]time.Time),
 		closed:        make(chan bool),
+		channels:      make(map[string]time.Time),
 		state:         make(chan *packet, 64),
 		sendQueue:     make(chan *packet, 128),
 		recvQueue:     make(chan *packet, 128),
@@ -87,6 +94,32 @@ func newLink(s transport.Socket) *link {
 	return l
 }
 
+func (l *link) connect(addr string) error {
+	c, err := l.transport.Dial(addr)
+	if err != nil {
+		return err
+	}
+
+	l.Lock()
+	l.Socket = c
+	l.Unlock()
+
+	return nil
+}
+
+func (l *link) accept(sock transport.Socket) error {
+	l.Lock()
+	l.Socket = sock
+	l.Unlock()
+	return nil
+}
+
+func (l *link) setLoopback(v bool) {
+	l.Lock()
+	l.loopback = v
+	l.Unlock()
+}
+
 // setRate sets the bits per second rate as a float64
 func (l *link) setRate(bits int64, delta time.Duration) {
 	// rate of send in bits per nanosecond
@@ -201,11 +234,15 @@ func (l *link) manage() {
 	t := time.NewTicker(time.Minute)
 	defer t.Stop()
 
+	// get link id
+	linkId := l.Id()
+
 	// used to send link state packets
 	send := func(b []byte) error {
 		return l.Send(&transport.Message{
 			Header: map[string]string{
-				"Micro-Method": "link",
+				"Micro-Method":  "link",
+				"Micro-Link-Id": linkId,
 			}, Body: b,
 		})
 	}
@@ -229,9 +266,7 @@ func (l *link) manage() {
 			// check the type of message
 			switch {
 			case bytes.Equal(p.message.Body, linkRequest):
-				l.RLock()
+				log.Tracef("Link %s received link request", linkId)
-				log.Tracef("Link %s received link request %v", l.id, p.message.Body)
-				l.RUnlock()
 
 				// send response
 				if err := send(linkResponse); err != nil {
@@ -242,9 +277,7 @@ func (l *link) manage() {
 			case bytes.Equal(p.message.Body, linkResponse):
 				// set round trip time
 				d := time.Since(now)
-				l.RLock()
+				log.Tracef("Link %s received link response in %v", linkId, d)
-				log.Tracef("Link %s received link response in %v", p.message.Body, d)
-				l.RUnlock()
 				// set the RTT
 				l.setRTT(d)
 			}
@@ -309,6 +342,12 @@ func (l *link) Rate() float64 {
 	return l.rate
 }
 
+func (l *link) Loopback() bool {
+	l.RLock()
+	defer l.RUnlock()
+	return l.loopback
+}
+
 // Length returns the roundtrip time as nanoseconds (lower is better).
 // Returns 0 where no measurement has been taken.
 func (l *link) Length() int64 {
@@ -320,7 +359,6 @@ func (l *link) Length() int64 {
 func (l *link) Id() string {
 	l.RLock()
 	defer l.RUnlock()
-
 	return l.id
 }
 

tunnel/listener.go

@@ -80,7 +80,7 @@ func (t *tunListener) process() {
 
 			// get a session
 			sess, ok := conns[sessionId]
-			log.Debugf("Tunnel listener received channel %s session %s type %s exists: %t", m.channel, sessionId, m.typ, ok)
+			log.Tracef("Tunnel listener received channel %s session %s type %s exists: %t", m.channel, sessionId, m.typ, ok)
 			if !ok {
 				// we only process open and session types
 				switch m.typ {
@@ -159,7 +159,7 @@ func (t *tunListener) process() {
 			case <-sess.closed:
 				delete(conns, sessionId)
 			case sess.recv <- m:
-				log.Debugf("Tunnel listener sent to recv chan channel %s session %s type %s", m.channel, sessionId, m.typ)
+				log.Tracef("Tunnel listener sent to recv chan channel %s session %s type %s", m.channel, sessionId, m.typ)
 			}
 		}
 	}

tunnel/session.go

@@ -356,11 +356,11 @@ func (s *session) Recv(m *transport.Message) error {
 	}
 
 	//log.Tracef("Received %+v from recv backlog", msg)
-	log.Debugf("Received %+v from recv backlog", msg)
+	log.Tracef("Received %+v from recv backlog", msg)
 
 	// decrypt the received payload using the token
 	// we have to used msg.session because multicast has a shared
-	// session id of "multicast" in this session struct on 
+	// session id of "multicast" in this session struct on
 	// the listener side
 	body, err := Decrypt(msg.data.Body, s.token+s.channel+msg.session)
 	if err != nil {

tunnel/tunnel.go

@@ -64,7 +64,9 @@ type Link interface {
 	Length() int64
 	// Current transfer rate as bits per second (lower is better)
 	Rate() float64
-	// State of the link e.g connected/closed
+	// Is this a loopback link
+	Loopback() bool
+	// State of the link: connected/closed/error
 	State() string
 	// honours transport socket
 	transport.Socket