update libp2p.New constructor to construct relayed/routed hosts

config/config.go

@@ -5,10 +5,13 @@ import (
 	"fmt"
 
 	bhost "github.com/libp2p/go-libp2p/p2p/host/basic"
+	relay "github.com/libp2p/go-libp2p/p2p/host/relay"
+	routed "github.com/libp2p/go-libp2p/p2p/host/routed"
 
 	logging "github.com/ipfs/go-log"
 	circuit "github.com/libp2p/go-libp2p-circuit"
 	crypto "github.com/libp2p/go-libp2p-crypto"
+	discovery "github.com/libp2p/go-libp2p-discovery"
 	host "github.com/libp2p/go-libp2p-host"
 	ifconnmgr "github.com/libp2p/go-libp2p-interface-connmgr"
 	pnet "github.com/libp2p/go-libp2p-interface-pnet"
@@ -16,6 +19,7 @@ import (
 	inet "github.com/libp2p/go-libp2p-net"
 	peer "github.com/libp2p/go-libp2p-peer"
 	pstore "github.com/libp2p/go-libp2p-peerstore"
+	routing "github.com/libp2p/go-libp2p-routing"
 	swarm "github.com/libp2p/go-libp2p-swarm"
 	tptu "github.com/libp2p/go-libp2p-transport-upgrader"
 	filter "github.com/libp2p/go-maddr-filter"
@@ -31,6 +35,13 @@ type AddrsFactory = bhost.AddrsFactory
 // NATManagerC is a NATManager constructor.
 type NATManagerC func(inet.Network) bhost.NATManager
 
+type Routing interface {
+	routing.ContentRouting
+	routing.PeerRouting
+}
+
+type RoutingC func(host.Host) (Routing, error)
+
 // Config describes a set of settings for a libp2p node
 //
 // This is *not* a stable interface. Use the options defined in the root
@@ -58,6 +69,8 @@ type Config struct {
 	Reporter    metrics.Reporter
 
 	DisablePing bool
+
+	Routing RoutingC
 }
 
 // NewNode constructs a new libp2p Host from the Config.
@@ -99,8 +112,8 @@ func (cfg *Config) NewNode(ctx context.Context) (host.Host, error) {
 		swrm.Filters = cfg.Filters
 	}
 
-	// TODO: make host implementation configurable.
-	h, err := bhost.NewHost(ctx, swrm, &bhost.HostOpts{
+	var h host.Host
+	h, err = bhost.NewHost(ctx, swrm, &bhost.HostOpts{
 		ConnManager:  cfg.ConnManager,
 		AddrsFactory: cfg.AddrsFactory,
 		NATManager:   cfg.NATManager,
@@ -158,7 +171,34 @@ func (cfg *Config) NewNode(ctx context.Context) (host.Host, error) {
 		return nil, err
 	}
 
-	// TODO: Configure routing (it's a pain to setup).
+	if cfg.Routing != nil {
+		router, err := cfg.Routing(h)
+		if err != nil {
+			h.Close()
+			return nil, err
+		}
+
+		if cfg.Relay {
+			discovery := discovery.NewRoutingDiscovery(router)
+
+			hop := false
+			for _, opt := range cfg.RelayOpts {
+				if opt == circuit.OptHop {
+					hop = true
+					break
+				}
+			}
+
+			if hop {
+				h = relay.NewRelayHost(swrm.Context(), h.(*bhost.BasicHost), discovery)
+			} else {
+				h = relay.NewAutoRelayHost(swrm.Context(), h.(*bhost.BasicHost), discovery)
+			}
+		}
+
+		h = routed.Wrap(h, router)
+	}
+
 	// TODO: Bootstrapping.
 
 	return h, nil

options.go

@@ -260,6 +260,17 @@ func Ping(enable bool) Option {
 	}
 }
 
+// Routing will configure libp2p to use routing.
+func Routing(rt config.RoutingC) Option {
+	return func(cfg *Config) error {
+		if cfg.Routing != nil {
+			return fmt.Errorf("cannot specified multiple routing options")
+		}
+		cfg.Routing = rt
+		return nil
+	}
+}
+
 // NoListenAddrs will configure libp2p to not listen by default.
 //
 // This will both clear any configured listen addrs and prevent libp2p from