Merge pull request #97 from libp2p/feat/just-tcp-example

Feat/just tcp example

examples/justtcp/README.md

+# libp2p 'just tcp' example
+
+## What this does
+This example starts up a libp2p swarm that listens for tcp connections behind a
+multistream muxer protocol of `/plaintext/1.0.0`. All connections made to it
+will be echoed back.
+
+## Building
+```
+$ go build
+```
+
+## Usage
+```
+$ ./justtcp
+```

examples/justtcp/main.go

+package main
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"os"
+
+	transport "github.com/ipfs/go-libp2p-transport"
+	ma "github.com/jbenet/go-multiaddr"
+	smux "github.com/jbenet/go-stream-muxer"
+	"github.com/libp2p/go-libp2p/p2p/net/swarm"
+)
+
+func fatal(i interface{}) {
+	fmt.Println(i)
+	os.Exit(1)
+}
+
+type NullMux struct{}
+
+type NullMuxConn struct {
+	net.Conn
+}
+
+func (c *NullMuxConn) AcceptStream() (smux.Stream, error) {
+	panic("We don't do this")
+}
+
+func (c *NullMuxConn) IsClosed() bool {
+	return false
+}
+
+func (c *NullMuxConn) OpenStream() (smux.Stream, error) {
+	panic("if only you could see how disappointed i am in you right now")
+}
+
+func (c *NullMuxConn) Serve(_ smux.StreamHandler) {
+}
+
+func (nm NullMux) NewConn(c net.Conn, server bool) (smux.Conn, error) {
+	return &NullMuxConn{c}, nil
+}
+
+var _ smux.Transport = (*NullMux)(nil)
+
+func main() {
+	laddr, err := ma.NewMultiaddr("/ip4/0.0.0.0/tcp/5555")
+	if err != nil {
+		fatal(err)
+	}
+
+	swarm.PSTransport = new(NullMux)
+
+	s := swarm.NewBlankSwarm(context.Background(), "bob", nil)
+
+	s.AddTransport(transport.NewTCPTransport())
+
+	err = s.AddListenAddr(laddr)
+	if err != nil {
+		fatal(err)
+	}
+
+	s.SetConnHandler(func(c *swarm.Conn) {
+		fmt.Println("CALLED OUR CONN HANDLER!")
+		defer c.Close()
+		buf := make([]byte, 1024)
+		for {
+			n, err := c.RawConn().Read(buf)
+			if err != nil {
+				fmt.Println(err)
+				return
+			}
+			fmt.Printf("read: %q\n", string(buf[:n]))
+
+			_, err = c.RawConn().Write(buf[:n])
+			if err != nil {
+				fmt.Println(err)
+				return
+			}
+		}
+	})
+
+	<-make(chan bool)
+}

p2p/net/conn/dial.go

@@ -65,7 +65,7 @@ func (d *Dialer) Dial(ctx context.Context, raddr ma.Multiaddr, remote peer.ID) (
 		}
 
 		cryptoProtoChoice := SecioTag
-		if !EncryptConnections {
+		if !EncryptConnections || d.PrivateKey == nil {
 			cryptoProtoChoice = NoEncryptionTag
 		}
 

p2p/net/conn/dial_test.go

@@ -259,8 +259,8 @@ func testDialerCloseEarly(t *testing.T, secure bool) {
 
 	// lol nesting
 	d2 := &Dialer{
-		LocalPeer: p2.ID,
-		// PrivateKey: key2, -- dont give it key. we'll just close the conn.
+		LocalPeer:  p2.ID,
+		PrivateKey: p2.PrivKey, //-- dont give it key. we'll just close the conn.
 	}
 	d2.AddDialer(dialer(t, p2.Addr))
 
@@ -527,7 +527,6 @@ func TestConcurrentAccept(t *testing.T) {
 
 	err = grc.CheckForLeaks(goroFilter)
 	if err != nil {
-		panic(err)
 		t.Fatal(err)
 	}
 }
@@ -644,7 +643,6 @@ func TestConnectionTimeouts(t *testing.T) {
 
 	err = grc.CheckForLeaks(goroFilter)
 	if err != nil {
-		panic(err)
 		t.Fatal(err)
 	}
 }

p2p/net/conn/listen.go

@@ -211,7 +211,7 @@ func WrapTransportListener(ctx context.Context, ml transport.Listener, local pee
 		return false
 	}
 
-	if EncryptConnections {
+	if EncryptConnections && sk != nil {
 		l.mux.AddHandler(SecioTag, nil)
 	} else {
 		l.mux.AddHandler(NoEncryptionTag, nil)

p2p/net/swarm/swarm.go

@@ -10,6 +10,14 @@ import (
 	"sync"
 	"time"
 
+	metrics "github.com/libp2p/go-libp2p/p2p/metrics"
+	mconn "github.com/libp2p/go-libp2p/p2p/metrics/conn"
+	inet "github.com/libp2p/go-libp2p/p2p/net"
+	conn "github.com/libp2p/go-libp2p/p2p/net/conn"
+	filter "github.com/libp2p/go-libp2p/p2p/net/filter"
+	addrutil "github.com/libp2p/go-libp2p/p2p/net/swarm/addr"
+
+	ci "github.com/ipfs/go-libp2p-crypto"
 	peer "github.com/ipfs/go-libp2p-peer"
 	pstore "github.com/ipfs/go-libp2p-peerstore"
 	transport "github.com/ipfs/go-libp2p-transport"
@@ -19,12 +27,6 @@ import (
 	pst "github.com/jbenet/go-stream-muxer"
 	"github.com/jbenet/goprocess"
 	goprocessctx "github.com/jbenet/goprocess/context"
-	metrics "github.com/libp2p/go-libp2p/p2p/metrics"
-	mconn "github.com/libp2p/go-libp2p/p2p/metrics/conn"
-	inet "github.com/libp2p/go-libp2p/p2p/net"
-	conn "github.com/libp2p/go-libp2p/p2p/net/conn"
-	filter "github.com/libp2p/go-libp2p/p2p/net/filter"
-	addrutil "github.com/libp2p/go-libp2p/p2p/net/swarm/addr"
 	psmss "github.com/whyrusleeping/go-smux-multistream"
 	spdy "github.com/whyrusleeping/go-smux-spdystream"
 	yamux "github.com/whyrusleeping/go-smux-yamux"
@@ -143,6 +145,31 @@ func NewSwarm(ctx context.Context, listenAddrs []ma.Multiaddr,
 	return s, nil
 }
 
+func NewBlankSwarm(ctx context.Context, id peer.ID, privkey ci.PrivKey) *Swarm {
+	s := &Swarm{
+		swarm:       ps.NewSwarm(PSTransport),
+		local:       id,
+		peers:       pstore.NewPeerstore(),
+		ctx:         ctx,
+		dialT:       DialTimeout,
+		notifs:      make(map[inet.Notifiee]ps.Notifiee),
+		fdRateLimit: make(chan struct{}, concurrentFdDials),
+		Filters:     filter.NewFilters(),
+		dialer:      conn.NewDialer(id, privkey, nil),
+	}
+
+	// configure Swarm
+	s.limiter = newDialLimiter(s.dialAddr)
+	s.proc = goprocessctx.WithContextAndTeardown(ctx, s.teardown)
+	s.SetConnHandler(nil) // make sure to setup our own conn handler.
+
+	return s
+}
+
+func (s *Swarm) AddTransport(t transport.Transport) {
+	s.transports = append(s.transports, t)
+}
+
 func (s *Swarm) teardown() error {
 	return s.swarm.Close()
 }

p2p/net/swarm/swarm_listen.go

@@ -13,37 +13,42 @@ import (
 	context "golang.org/x/net/context"
 )
 
+func (s *Swarm) AddListenAddr(a ma.Multiaddr) error {
+	tpt := s.transportForAddr(a)
+	if tpt == nil {
+		return fmt.Errorf("no transport for address: %s", a)
+	}
+
+	d, err := tpt.Dialer(a, transport.TimeoutOpt(DialTimeout), transport.ReusePorts)
+	if err != nil {
+		return err
+	}
+
+	s.dialer.AddDialer(d)
+
+	list, err := tpt.Listen(a)
+	if err != nil {
+		return err
+	}
+
+	err = s.addListener(list)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
 // Open listeners and reuse-dialers for the given addresses
 func (s *Swarm) setupInterfaces(addrs []ma.Multiaddr) error {
 	errs := make([]error, len(addrs))
 	var succeeded int
 	for i, a := range addrs {
-		tpt := s.transportForAddr(a)
-		if tpt == nil {
-			errs[i] = fmt.Errorf("no transport for address: %s", a)
-			continue
-		}
-
-		d, err := tpt.Dialer(a, transport.TimeoutOpt(DialTimeout), transport.ReusePorts)
-		if err != nil {
-			errs[i] = err
-			continue
-		}
-
-		s.dialer.AddDialer(d)
-
-		list, err := tpt.Listen(a)
-		if err != nil {
+		if err := s.AddListenAddr(a); err != nil {
 			errs[i] = err
-			continue
+		} else {
+			succeeded++
 		}
-
-		err = s.addListener(list)
-		if err != nil {
-			errs[i] = err
-			continue
-		}
-		succeeded++
 	}
 
 	for i, e := range errs {
@@ -51,6 +56,7 @@ func (s *Swarm) setupInterfaces(addrs []ma.Multiaddr) error {
 			log.Warning("listen on %s failed: %s", addrs[i], errs[i])
 		}
 	}
+
 	if succeeded == 0 && len(addrs) > 0 {
 		return fmt.Errorf("failed to listen on any addresses: %s", errs)
 	}
@@ -83,7 +89,7 @@ func (s *Swarm) addListener(tptlist transport.Listener) error {
 
 	list.SetAddrFilters(s.Filters)
 
-	if cw, ok := list.(conn.ListenerConnWrapper); ok {
+	if cw, ok := list.(conn.ListenerConnWrapper); ok && s.bwc != nil {
 		cw.SetConnWrapper(func(c transport.Conn) transport.Conn {
 			return mconn.WrapConn(s.bwc, c)
 		})