Merge pull request #210 from libp2p/feat/circuit-relay

Circuit Relay integration with basic_host

p2p/host/basic/basic_host.go

@@ -9,6 +9,7 @@ import (
 
 	logging "github.com/ipfs/go-log"
 	goprocess "github.com/jbenet/goprocess"
+	circuit "github.com/libp2p/go-libp2p-circuit"
 	connmgr "github.com/libp2p/go-libp2p-connmgr"
 	metrics "github.com/libp2p/go-libp2p-metrics"
 	mstream "github.com/libp2p/go-libp2p-metrics/stream"
@@ -97,10 +98,16 @@ type HostOpts struct {
 
 	// ConnManager is a libp2p connection manager
 	ConnManager connmgr.ConnManager
+
+	// Relay indicates whether the host should use circuit relay transport
+	EnableRelay bool
+
+	// RelayOpts are options for the relay transport; only meaningful when Relay=true
+	RelayOpts []circuit.RelayOpt
 }
 
 // NewHost constructs a new *BasicHost and activates it by attaching its stream and connection handlers to the given inet.Network.
-func NewHost(net inet.Network, opts *HostOpts) *BasicHost {
+func NewHost(ctx context.Context, net inet.Network, opts *HostOpts) (*BasicHost, error) {
 	h := &BasicHost{
 		network:    net,
 		mux:        msmux.NewMultistreamMuxer(),
@@ -143,17 +150,32 @@ func NewHost(net inet.Network, opts *HostOpts) *BasicHost {
 		h.cmgr = opts.ConnManager
 	}
 
+	var relayCtx context.Context
+	var relayCancel func()
+
 	h.proc = goprocess.WithTeardown(func() error {
 		if h.natmgr != nil {
 			h.natmgr.Close()
 		}
+		if relayCancel != nil {
+			relayCancel()
+		}
 		return h.Network().Close()
 	})
 
 	net.SetConnHandler(h.newConnHandler)
 	net.SetStreamHandler(h.newStreamHandler)
 
-	return h
+	if opts.EnableRelay {
+		relayCtx, relayCancel = context.WithCancel(ctx)
+		err := circuit.AddRelayTransport(relayCtx, h, opts.RelayOpts...)
+		if err != nil {
+			h.Close()
+			return nil, err
+		}
+	}
+
+	return h, nil
 }
 
 // New constructs and sets up a new *BasicHost with given Network and options.
@@ -178,7 +200,14 @@ func New(net inet.Network, opts ...interface{}) *BasicHost {
 		}
 	}
 
-	return NewHost(net, hostopts)
+	h, err := NewHost(context.Background(), net, hostopts)
+	if err != nil {
+		// this cannot happen with legacy options
+		// plus we want to keep the (deprecated) legacy interface unchanged
+		panic(err)
+	}
+
+	return h
 }
 
 // newConnHandler is the remote-opened conn handler for inet.Network

p2p/net/mock/mock_net.go

@@ -87,7 +87,11 @@ func (mn *mocknet) AddPeerWithPeerstore(p peer.ID, ps pstore.Peerstore) (host.Ho
 	opts := &bhost.HostOpts{
 		NegotiationTimeout: -1,
 	}
-	h := bhost.NewHost(n, opts)
+
+	h, err := bhost.NewHost(mn.ctx, n, opts)
+	if err != nil {
+		return nil, err
+	}
 
 	mn.proc.AddChild(n.proc)
 

package.json

@@ -268,6 +268,12 @@
       "hash": "QmXYjuNuxVzXKJCfWasQk1RqkhVLDM9jtUKhqc2WPQmFSB",
       "name": "go-libp2p-peer",
       "version": "2.2.0"
+    },
+    {
+      "author": "vyzo",
+      "hash": "QmYv8PxtikjeL6AfsheUiJfoFRzKvx8hdwRf4odBWH7mQx",
+      "name": "go-libp2p-circuit",
+      "version": "1.1.3"
     }
   ],
   "gxVersion": "0.4.0",