make randezvous key a constant

p2p/host/relay/autorelay.go

@@ -20,6 +20,10 @@ import (
 	manet "github.com/multiformats/go-multiaddr-net"
 )
 
+const (
+	RelayRenezvous = "/libp2p/relay"
+)
+
 var (
 	DesiredRelays = 3
 
@@ -121,7 +125,7 @@ func (h *AutoRelayHost) findRelays(ctx context.Context) {
 	}
 
 	dctx, cancel := context.WithTimeout(ctx, 60*time.Second)
-	pis, err := discovery.FindPeers(dctx, h.discover, "/libp2p/relay", limit)
+	pis, err := discovery.FindPeers(dctx, h.discover, RelayRenezvous, limit)
 	cancel()
 	if err != nil {
 		log.Debugf("error discovering relays: %s", err.Error())

p2p/host/relay/relay.go

@@ -25,7 +25,7 @@ func NewRelayHost(ctx context.Context, bhost *basic.BasicHost, advertise discove
 		advertise: advertise,
 	}
 	bhost.AddrsFactory = h.hostAddrs
-	discovery.Advertise(ctx, advertise, "/libp2p/relay")
+	discovery.Advertise(ctx, advertise, RelayRenezvous)
 	return h
 }