basichost: use autonatv2 to verify reachability

.golangci.yml

@@ -8,6 +8,8 @@ linters:
     - revive
     - unused
     - prealloc
+  disable:
+    - errcheck
 
   settings:
     revive:

config/config.go

@@ -33,6 +33,7 @@ import (
 	routed "github.com/libp2p/go-libp2p/p2p/host/routed"
 	"github.com/libp2p/go-libp2p/p2p/net/swarm"
 	tptu "github.com/libp2p/go-libp2p/p2p/net/upgrader"
+	"github.com/libp2p/go-libp2p/p2p/protocol/autonatv2"
 	circuitv2 "github.com/libp2p/go-libp2p/p2p/protocol/circuitv2/client"
 	relayv2 "github.com/libp2p/go-libp2p/p2p/protocol/circuitv2/relay"
 	"github.com/libp2p/go-libp2p/p2p/protocol/holepunch"
@@ -413,15 +414,7 @@ func (cfg *Config) addTransports() ([]fx.Option, error) {
 	return fxopts, nil
 }
 
-func (cfg *Config) newBasicHost(swrm *swarm.Swarm, eventBus event.Bus) (*bhost.BasicHost, error) {
-	var autonatv2Dialer host.Host
-	if cfg.EnableAutoNATv2 {
-		ah, err := cfg.makeAutoNATV2Host()
-		if err != nil {
-			return nil, err
-		}
-		autonatv2Dialer = ah
-	}
+func (cfg *Config) newBasicHost(swrm *swarm.Swarm, eventBus event.Bus, an *autonatv2.AutoNAT) (*bhost.BasicHost, error) {
 	h, err := bhost.NewHost(swrm, &bhost.HostOpts{
 		EventBus:                        eventBus,
 		ConnManager:                     cfg.ConnManager,
@@ -437,8 +430,7 @@ func (cfg *Config) newBasicHost(swrm *swarm.Swarm, eventBus event.Bus) (*bhost.B
 		EnableMetrics:                   !cfg.DisableMetrics,
 		PrometheusRegisterer:            cfg.PrometheusRegisterer,
 		DisableIdentifyAddressDiscovery: cfg.DisableIdentifyAddressDiscovery,
-		EnableAutoNATv2:                 cfg.EnableAutoNATv2,
-		AutoNATv2Dialer:                 autonatv2Dialer,
+		AutoNATv2:                       an,
 	})
 	if err != nil {
 		return nil, err
@@ -517,6 +509,24 @@ func (cfg *Config) NewNode() (host.Host, error) {
 			})
 			return sw, nil
 		}),
+		fx.Provide(func() (*autonatv2.AutoNAT, error) {
+			if !cfg.EnableAutoNATv2 {
+				return nil, nil
+			}
+			ah, err := cfg.makeAutoNATV2Host()
+			if err != nil {
+				return nil, err
+			}
+			var mt autonatv2.MetricsTracer
+			if !cfg.DisableMetrics {
+				mt = autonatv2.NewMetricsTracer(cfg.PrometheusRegisterer)
+			}
+			autoNATv2, err := autonatv2.New(ah, autonatv2.WithMetricsTracer(mt))
+			if err != nil {
+				return nil, fmt.Errorf("failed to create autonatv2: %w", err)
+			}
+			return autoNATv2, nil
+		}),
 		fx.Provide(cfg.newBasicHost),
 		fx.Provide(func(bh *bhost.BasicHost) identify.IDService {
 			return bh.IDService()

core/event/reachability.go

@@ -2,6 +2,7 @@ package event
 
 import (
 	"github.com/libp2p/go-libp2p/core/network"
+	ma "github.com/multiformats/go-multiaddr"
 )
 
 // EvtLocalReachabilityChanged is an event struct to be emitted when the local's
@@ -11,3 +12,12 @@ import (
 type EvtLocalReachabilityChanged struct {
 	Reachability network.Reachability
 }
+
+// EvtHostReachableAddrsChanged is sent when host's reachable or unreachable addresses change
+// Reachable and Unreachable both contain only Public IP or DNS addresses
+//
+// Experimental: This API is unstable. Any changes to this event will be done without a deprecation notice.
+type EvtHostReachableAddrsChanged struct {
+	Reachable   []ma.Multiaddr
+	Unreachable []ma.Multiaddr
+}