Replaced global variables with closure

dht-interop.go

@@ -17,10 +17,8 @@ import (
 	"github.com/libp2p/go-libp2p-crypto"
 )
 
-var ho h.Host
+func createConnHandler(dhtPtr *dht.IpfsDHT, ho h.Host) func(conn net.Conn) {
-var dhtPtr *dht.IpfsDHT
+	return func(conn net.Conn) {
-
-func handleConn(conn net.Conn) {
 		ctx := context.Background()
 
 		d := *dhtPtr
@@ -62,6 +60,7 @@ func handleConn(conn net.Conn) {
 			fmt.Printf("no remote providers!\n")
 		}
 	}
+}
 
 func main() {
 	ctx := context.Background()
@@ -84,7 +83,7 @@ func main() {
 	}
 
 	//
-	// Set up a libp2p host.
+	// Set up a libp2p host listening on every interface
 	//
 	host, err := libp2p.New(ctx,
 		libp2p.ListenAddrStrings("/ip4/0.0.0.0/tcp/9876"),
@@ -95,22 +94,21 @@ func main() {
 		panic(err)
 	}
 
-	host.Network().SetConnHandler(handleConn)
-
-	ho = host
-
-	fmt.Printf("To connect, run:\n")
-	fmt.Printf("node js-dht-test/index.js %s/ipfs/%s\n", host.Addrs()[0], host.ID().Pretty())
-
 	//
-	// Construct a DHT for discovery.
+	// Construct a DHT for discovery
 	//
-	d, err := dht.New(ctx, host, dhtopts.Client(false))
+	dhtPtr, err := dht.New(ctx, host, dhtopts.Client(false))
 	if err != nil {
 		panic(err)
 	}
 
-	dhtPtr = d
+	//
+	// Accept connections from peers
+	//
+	f := createConnHandler(dhtPtr, host)
+	host.Network().SetConnHandler(f)
+	fmt.Printf("To connect, run:\n")
+	fmt.Printf("node js-dht-test/index.js %s/ipfs/%s\n", host.Addrs()[0], host.ID().Pretty())
 
 	select {}
 }