basic net package (no tests yet)

Implements:
- Conn
- Dial, Dialer
- Listen, Listener

net/net.go

+package net
+
+import (
+	"fmt"
+	"net"
+
+	ma "github.com/jbenet/go-multiaddr"
+)
+
+// Conn is the equivalent of a net.Conn object. It is the
+// result of calling the Dial or Listen functions in this
+// package, with associated local and remote Multiaddrs.
+type Conn interface {
+	net.Conn
+
+	// LocalMultiaddr returns the local Multiaddr associated
+	// with this connection
+	LocalMultiaddr() ma.Multiaddr
+
+	// RemoteMultiaddr returns the remote Multiaddr associated
+	// with this connection
+	RemoteMultiaddr() ma.Multiaddr
+}
+
+// WrapNetConn wraps a net.Conn object with a Multiaddr
+// friendly Conn.
+func WrapNetConn(nconn net.Conn) (Conn, error) {
+
+	laddr, err := FromNetAddr(nconn.LocalAddr())
+	if err != nil {
+		return nil, fmt.Errorf("failed to convert nconn.LocalAddr: %s", err)
+	}
+
+	raddr, err := FromNetAddr(nconn.RemoteAddr())
+	if err != nil {
+		return nil, fmt.Errorf("failed to convert nconn.RemoteAddr: %s", err)
+	}
+
+	return &maConn{
+		Conn:  nconn,
+		laddr: laddr,
+		raddr: raddr,
+	}, nil
+}
+
+// maConn implements the Conn interface. It's a thin wrapper
+// around a net.Conn
+type maConn struct {
+	net.Conn
+	laddr ma.Multiaddr
+	raddr ma.Multiaddr
+}
+
+// LocalMultiaddr returns the local address associated with
+// this connection
+func (c *maConn) LocalMultiaddr() ma.Multiaddr {
+	return c.laddr
+}
+
+// RemoteMultiaddr returns the remote address associated with
+// this connection
+func (c *maConn) RemoteMultiaddr() ma.Multiaddr {
+	return c.raddr
+}
+
+// Dialer contains options for connecting to an address. It
+// is effectively the same as net.Dialer, but its LocalAddr
+// and RemoteAddr options are Multiaddrs, instead of net.Addrs.
+type Dialer struct {
+
+	// Dialer is just an embed net.Dialer, with all its options.
+	net.Dialer
+
+	// LocalAddr is the local address to use when dialing an
+	// address. The address must be of a compatible type for the
+	// network being dialed.
+	// If nil, a local address is automatically chosen.
+	LocalAddr ma.Multiaddr
+}
+
+// Dial connects to a remote address, using the options of the
+// Dialer. Dialer uses an underlying net.Dialer to Dial a
+// net.Conn, then wraps that in a Conn object (with local and
+// remote Multiaddrs).
+func (d *Dialer) Dial(remote ma.Multiaddr) (Conn, error) {
+
+	// if a LocalAddr is specified, use it on the embedded dialer.
+	if d.LocalAddr != nil {
+		// convert our multiaddr to net.Addr friendly
+		naddr, err := ToNetAddr(d.LocalAddr)
+		if err != nil {
+			return nil, err
+		}
+
+		// set the dialer's LocalAddr as naddr
+		d.Dialer.LocalAddr = naddr
+	}
+
+	// get the net.Dial friendly arguments from the remote addr
+	rnet, rnaddr, err := DialArgs(remote)
+	if err != nil {
+		return nil, err
+	}
+
+	// ok, Dial!
+	nconn, err := d.Dialer.Dial(rnet, rnaddr)
+	if err != nil {
+		return nil, err
+	}
+
+	// get local address (pre-specified or assigned within net.Conn)
+	local := d.LocalAddr
+	if local == nil {
+		local, err = FromNetAddr(nconn.LocalAddr())
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return &maConn{
+		Conn:  nconn,
+		laddr: local,
+		raddr: remote,
+	}, nil
+}
+
+// Dial connects to a remote address. It uses an underlying net.Conn,
+// then wraps it in a Conn object (with local and remote Multiaddrs).
+func Dial(remote ma.Multiaddr) (Conn, error) {
+	return (&Dialer{}).Dial(remote)
+}
+
+// A Listener is a generic network listener for stream-oriented protocols.
+// it uses an embedded net.Listener, overriding net.Listener.Accept to
+// return a Conn and providing Multiaddr.
+type Listener interface {
+
+	// NetListener returns the embedded net.Listener. Use with caution.
+	NetListener() net.Listener
+
+	// Accept waits for and returns the next connection to the listener.
+	// Returns a Multiaddr friendly Conn
+	Accept() (Conn, error)
+
+	// Close closes the listener.
+	// Any blocked Accept operations will be unblocked and return errors.
+	Close() error
+
+	// Multiaddr returns the listener's (local) Multiaddr.
+	Multiaddr() ma.Multiaddr
+
+	// Addr returns the net.Listener's network address.
+	Addr() net.Addr
+}
+
+// maListener implements Listener
+type maListener struct {
+	net.Listener
+	laddr ma.Multiaddr
+}
+
+// NetListener returns the embedded net.Listener. Use with caution.
+func (l *maListener) NetListener() net.Listener {
+	return l.Listener
+}
+
+// Accept waits for and returns the next connection to the listener.
+// Returns a Multiaddr friendly Conn
+func (l *maListener) Accept() (Conn, error) {
+	nconn, err := l.Listener.Accept()
+	if err != nil {
+		return nil, err
+	}
+
+	raddr, err := FromNetAddr(nconn.RemoteAddr())
+	if err != nil {
+		return nil, fmt.Errorf("failed to convert connn.RemoteAddr: %s", err)
+	}
+
+	return &maConn{
+		Conn:  nconn,
+		laddr: l.laddr,
+		raddr: raddr,
+	}, nil
+}
+
+// Multiaddr returns the listener's (local) Multiaddr.
+func (l *maListener) Multiaddr() ma.Multiaddr {
+	return l.laddr
+}
+
+// Addr returns the listener's network address.
+func (l *maListener) Addr() net.Addr {
+	return l.Listener.Addr()
+}
+
+// Listen announces on the local network address laddr.
+// The Multiaddr must be a "ThinWaist" stream-oriented network:
+// ip4/tcp, ip6/tcp, (TODO: unix, unixpacket)
+// See Dial for the syntax of laddr.
+func Listen(laddr ma.Multiaddr) (Listener, error) {
+
+	// get the net.Listen friendly arguments from the remote addr
+	lnet, lnaddr, err := DialArgs(laddr)
+	if err != nil {
+		return nil, err
+	}
+
+	nl, err := net.Listen(lnet, lnaddr)
+	if err != nil {
+		return nil, err
+	}
+
+	return &maListener{
+		Listener: nl,
+		laddr:    laddr,
+	}, nil
+}

net/net_test.go

+package net