first hack at a nice libp2p constructor

examples/echo/main.go

@@ -12,17 +12,14 @@ import (
 	mrand "math/rand"
 
 	golog "github.com/ipfs/go-log"
+	libp2p "github.com/libp2p/go-libp2p"
 	crypto "github.com/libp2p/go-libp2p-crypto"
 	host "github.com/libp2p/go-libp2p-host"
 	net "github.com/libp2p/go-libp2p-net"
 	peer "github.com/libp2p/go-libp2p-peer"
 	pstore "github.com/libp2p/go-libp2p-peerstore"
-	swarm "github.com/libp2p/go-libp2p-swarm"
-	bhost "github.com/libp2p/go-libp2p/p2p/host/basic"
 	ma "github.com/multiformats/go-multiaddr"
 	gologging "github.com/whyrusleeping/go-logging"
-	msmux "github.com/whyrusleeping/go-smux-multistream"
-	yamux "github.com/whyrusleeping/go-smux-yamux"
 )
 
 // makeBasicHost creates a LibP2P host with a random peer ID listening on the
@@ -41,61 +38,31 @@ func makeBasicHost(listenPort int, secio bool, randseed int64) (host.Host, error
 
 	// Generate a key pair for this host. We will use it at least
 	// to obtain a valid host ID.
-	priv, pub, err := crypto.GenerateKeyPairWithReader(crypto.RSA, 2048, r)
+	priv, _, err := crypto.GenerateKeyPairWithReader(crypto.RSA, 2048, r)
 	if err != nil {
 		return nil, err
 	}
 
-	// Obtain Peer ID from public key
-	pid, err := peer.IDFromPublicKey(pub)
-	if err != nil {
-		return nil, err
+	opts := []libp2p.Option{
+		libp2p.ListenAddrStrings(fmt.Sprintf("/ip4/127.0.0.1/tcp/%d", listenPort)),
+		libp2p.Identity(priv),
 	}
 
-	// Create a multiaddress
-	addr, err := ma.NewMultiaddr(fmt.Sprintf("/ip4/127.0.0.1/tcp/%d", listenPort))
-
-	if err != nil {
-		return nil, err
+	if !secio {
+		opts = append(opts, libp2p.NoEncryption())
 	}
 
-	// Create a peerstore
-	ps := pstore.NewPeerstore()
-
-	// If using secio, we add the keys to the peerstore
-	// for this peer ID.
-	if secio {
-		ps.AddPrivKey(pid, priv)
-		ps.AddPubKey(pid, pub)
-	}
-
-	// Set up stream multiplexer
-	tpt := msmux.NewBlankTransport()
-	tpt.AddTransport("/yamux/1.0.0", yamux.DefaultTransport)
-
-	// Create swarm (implements libP2P Network)
-	swrm, err := swarm.NewSwarmWithProtector(
-		context.Background(),
-		[]ma.Multiaddr{addr},
-		pid,
-		ps,
-		nil,
-		tpt,
-		nil,
-	)
+	basicHost, err := libp2p.New(context.Background(), opts...)
 	if err != nil {
 		return nil, err
 	}
 
-	netw := (*swarm.Network)(swrm)
-
-	basicHost := bhost.New(netw)
-
 	// Build host multiaddress
 	hostAddr, _ := ma.NewMultiaddr(fmt.Sprintf("/ipfs/%s", basicHost.ID().Pretty()))
 
 	// Now we can build a full multiaddress to reach this host
 	// by encapsulating both addresses:
+	addr := basicHost.Addrs()[0]
 	fullAddr := addr.Encapsulate(hostAddr)
 	log.Printf("I am %s\n", fullAddr)
 	if secio {

examples/libp2p-host/host.go

@@ -5,47 +5,43 @@ import (
 	"crypto/rand"
 	"fmt"
 
+	libp2p "github.com/libp2p/go-libp2p"
 	crypto "github.com/libp2p/go-libp2p-crypto"
-	peer "github.com/libp2p/go-libp2p-peer"
-	pstore "github.com/libp2p/go-libp2p-peerstore"
-	swarm "github.com/libp2p/go-libp2p-swarm"
-	bhost "github.com/libp2p/go-libp2p/p2p/host/basic"
-	ma "github.com/multiformats/go-multiaddr"
 )
 
 func main() {
-	// Generate an identity keypair using go's cryptographic randomness source
-	priv, pub, err := crypto.GenerateEd25519Key(rand.Reader)
-	if err != nil {
-		panic(err)
-	}
+	// The context governs the lifetime of the libp2p node
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
 
-	// A peers ID is the hash of its public key
-	pid, err := peer.IDFromPublicKey(pub)
+	// To construct a simple host with all the default settings, just use `New`
+	h, err := libp2p.New(ctx)
 	if err != nil {
 		panic(err)
 	}
 
-	// We've created the identity, now we need to store it.
-	// A peerstore holds information about peers, including your own
-	ps := pstore.NewPeerstore()
-	ps.AddPrivKey(pid, priv)
-	ps.AddPubKey(pid, pub)
+	fmt.Printf("Hello World, my hosts ID is %s\n", h.ID())
+
+	// If you want more control over the configuration, you can specify some
+	// options to the constructor
 
-	maddr, err := ma.NewMultiaddr("/ip4/0.0.0.0/tcp/9000")
+	// Set your own keypair
+	priv, _, err := crypto.GenerateEd25519Key(rand.Reader)
 	if err != nil {
 		panic(err)
 	}
 
-	// Make a context to govern the lifespan of the swarm
-	ctx := context.Background()
+	h2, err := libp2p.New(ctx,
+		// Use your own created keypair
+		libp2p.Identity(priv),
 
-	// Put all this together
-	netw, err := swarm.NewNetwork(ctx, []ma.Multiaddr{maddr}, pid, ps, nil)
+		// Set your own listen address
+		// The config takes an array of addresses, specify as many as you want.
+		libp2p.ListenAddrStrings("/ip4/0.0.0.0/tcp/9000"),
+	)
 	if err != nil {
 		panic(err)
 	}
 
-	myhost := bhost.New(netw)
-	fmt.Printf("Hello World, my hosts ID is %s\n", myhost.ID())
+	fmt.Printf("Hello World, my second hosts ID is %s\n", h2.ID())
 }

libp2p.go

@@ -0,0 +1,221 @@
+package libp2p
+
+import (
+	"context"
+	"crypto/rand"
+	"fmt"
+
+	crypto "github.com/libp2p/go-libp2p-crypto"
+	host "github.com/libp2p/go-libp2p-host"
+	pnet "github.com/libp2p/go-libp2p-interface-pnet"
+	metrics "github.com/libp2p/go-libp2p-metrics"
+	peer "github.com/libp2p/go-libp2p-peer"
+	pstore "github.com/libp2p/go-libp2p-peerstore"
+	swarm "github.com/libp2p/go-libp2p-swarm"
+	transport "github.com/libp2p/go-libp2p-transport"
+	bhost "github.com/libp2p/go-libp2p/p2p/host/basic"
+	mux "github.com/libp2p/go-stream-muxer"
+	ma "github.com/multiformats/go-multiaddr"
+	mplex "github.com/whyrusleeping/go-smux-multiplex"
+	msmux "github.com/whyrusleeping/go-smux-multistream"
+	yamux "github.com/whyrusleeping/go-smux-yamux"
+)
+
+// Config describes a set of settings for a libp2p node
+type Config struct {
+	Transports   []transport.Transport
+	Muxer        mux.Transport
+	ListenAddrs  []ma.Multiaddr
+	PeerKey      crypto.PrivKey
+	Peerstore    pstore.Peerstore
+	Protector    pnet.Protector
+	Reporter     metrics.Reporter
+	DisableSecio bool
+}
+
+type Option func(cfg *Config) error
+
+func Transports(tpts ...transport.Transport) Option {
+	return func(cfg *Config) error {
+		cfg.Transports = append(cfg.Transports, tpts...)
+		return nil
+	}
+}
+
+func ListenAddrStrings(s ...string) Option {
+	return func(cfg *Config) error {
+		for _, addrstr := range s {
+			a, err := ma.NewMultiaddr(addrstr)
+			if err != nil {
+				return err
+			}
+			cfg.ListenAddrs = append(cfg.ListenAddrs, a)
+		}
+		return nil
+	}
+}
+
+func ListenAddrs(addrs ...ma.Multiaddr) Option {
+	return func(cfg *Config) error {
+		cfg.ListenAddrs = append(cfg.ListenAddrs, addrs...)
+		return nil
+	}
+}
+
+type transportEncOpt int
+
+const (
+	EncPlaintext = transportEncOpt(0)
+	EncSecio     = transportEncOpt(1)
+)
+
+func TransportEncryption(tenc ...transportEncOpt) Option {
+	return func(cfg *Config) error {
+		if len(tenc) != 1 {
+			return fmt.Errorf("can only specify a single transport encryption option right now")
+		}
+
+		// TODO: actually make this pluggable, otherwise tls will get tricky
+		switch tenc[0] {
+		case EncPlaintext:
+			cfg.DisableSecio = true
+		case EncSecio:
+			// noop
+		default:
+			return fmt.Errorf("unrecognized transport encryption option: %d", tenc[0])
+		}
+		return nil
+	}
+}
+
+func NoEncryption() Option {
+	return TransportEncryption(EncPlaintext)
+}
+
+func Muxer(m mux.Transport) Option {
+	return func(cfg *Config) error {
+		if cfg.Muxer != nil {
+			return fmt.Errorf("cannot specify multiple muxer options")
+		}
+
+		cfg.Muxer = m
+		return nil
+	}
+}
+
+func Peerstore(ps pstore.Peerstore) Option {
+	return func(cfg *Config) error {
+		if cfg.Peerstore != nil {
+			return fmt.Errorf("cannot specify multiple peerstore options")
+		}
+
+		cfg.Peerstore = ps
+		return nil
+	}
+}
+
+func PrivateNetwork(prot pnet.Protector) Option {
+	return func(cfg *Config) error {
+		if cfg.Protector != nil {
+			return fmt.Errorf("cannot specify multiple private network options")
+		}
+
+		cfg.Protector = prot
+		return nil
+	}
+}
+
+func BandwidthReporter(rep metrics.Reporter) Option {
+	return func(cfg *Config) error {
+		if cfg.Reporter != nil {
+			return fmt.Errorf("cannot specify multiple bandwidth reporter options")
+		}
+
+		cfg.Reporter = rep
+		return nil
+	}
+}
+
+func Identity(sk crypto.PrivKey) Option {
+	return func(cfg *Config) error {
+		if cfg.PeerKey != nil {
+			return fmt.Errorf("cannot specify multiple identities")
+		}
+
+		cfg.PeerKey = sk
+		return nil
+	}
+}
+
+func New(ctx context.Context, opts ...Option) (host.Host, error) {
+	var cfg Config
+	for _, opt := range opts {
+		if err := opt(&cfg); err != nil {
+			return nil, err
+		}
+	}
+
+	return newWithCfg(ctx, &cfg)
+}
+
+func newWithCfg(ctx context.Context, cfg *Config) (host.Host, error) {
+	// If no key was given, generate a random 2048 bit RSA key
+	if cfg.PeerKey == nil {
+		priv, _, err := crypto.GenerateKeyPairWithReader(crypto.RSA, 2048, rand.Reader)
+		if err != nil {
+			return nil, err
+		}
+		cfg.PeerKey = priv
+	}
+
+	// Obtain Peer ID from public key
+	pid, err := peer.IDFromPublicKey(cfg.PeerKey.GetPublic())
+	if err != nil {
+		return nil, err
+	}
+
+	// Create a new blank peerstore if none was passed in
+	ps := cfg.Peerstore
+	if ps == nil {
+		ps = pstore.NewPeerstore()
+	}
+
+	// If secio is disabled, don't add our private key to the peerstore
+	if !cfg.DisableSecio {
+		ps.AddPrivKey(pid, cfg.PeerKey)
+		ps.AddPubKey(pid, cfg.PeerKey.GetPublic())
+	}
+
+	swrm, err := swarm.NewSwarmWithProtector(ctx, cfg.ListenAddrs, pid, ps, cfg.Protector, cfg.Muxer, cfg.Reporter)
+	if err != nil {
+		return nil, err
+	}
+
+	netw := (*swarm.Network)(swrm)
+
+	return bhost.New(netw), nil
+}
+
+func DefaultMuxer() mux.Transport {
+	// Set up stream multiplexer
+	tpt := msmux.NewBlankTransport()
+
+	// By default, support yamux and multiplex
+	tpt.AddTransport("/yamux/1.0.0", yamux.DefaultTransport)
+	tpt.AddTransport("/mplex/6.3.0", mplex.DefaultTransport)
+
+	return tpt
+}
+
+func Defaults(cfg *Config) error {
+	// Create a multiaddress that listens on a random port on all interfaces
+	addr, err := ma.NewMultiaddr("/ip4/0.0.0.0/tcp/0")
+	if err != nil {
+		return err
+	}
+
+	cfg.ListenAddrs = []ma.Multiaddr{addr}
+	cfg.Peerstore = pstore.NewPeerstore()
+	cfg.Muxer = DefaultMuxer()
+	return nil
+}

package.json

@@ -280,6 +280,12 @@
       "hash": "QmSAJm4QdTJ3EGF2cvgNcQyXTEbxqWSW1x4kCVV1aJQUQr",
       "name": "go-libp2p-interface-connmgr",
       "version": "0.0.4"
+    },
+    {
+      "author": "whyrusleeping",
+      "hash": "QmREBy6TSjLQMtYFhjf97cypsUTzBagcwamWocKHFCTb1e",
+      "name": "go-smux-multiplex",
+      "version": "3.0.4"
     }
   ],
   "gxVersion": "0.4.0",