Merge pull request #15 from jbenet/feat/pluggable

make multiaddr-net more pluggable

convert.go

@@ -13,103 +13,41 @@ var errIncorrectNetAddr = fmt.Errorf("incorrect network addr conversion")
 
 // FromNetAddr converts a net.Addr type to a Multiaddr.
 func FromNetAddr(a net.Addr) (ma.Multiaddr, error) {
+	return defaultCodecs.FromNetAddr(a)
+}
+
+func (cm *CodecMap) FromNetAddr(a net.Addr) (ma.Multiaddr, error) {
 	if a == nil {
 		return nil, fmt.Errorf("nil multiaddr")
 	}
-
-	switch a.Network() {
-	case "tcp", "tcp4", "tcp6":
-		ac, ok := a.(*net.TCPAddr)
-		if !ok {
-			return nil, errIncorrectNetAddr
-		}
-
-		// Get IP Addr
-		ipm, err := FromIP(ac.IP)
-		if err != nil {
-			return nil, errIncorrectNetAddr
-		}
-
-		// Get TCP Addr
-		tcpm, err := ma.NewMultiaddr(fmt.Sprintf("/tcp/%d", ac.Port))
-		if err != nil {
-			return nil, errIncorrectNetAddr
-		}
-
-		// Encapsulate
-		return ipm.Encapsulate(tcpm), nil
-
-	case "udp", "upd4", "udp6":
-		ac, ok := a.(*net.UDPAddr)
-		if !ok {
-			return nil, errIncorrectNetAddr
-		}
-
-		// Get IP Addr
-		ipm, err := FromIP(ac.IP)
-		if err != nil {
-			return nil, errIncorrectNetAddr
-		}
-
-		// Get UDP Addr
-		udpm, err := ma.NewMultiaddr(fmt.Sprintf("/udp/%d", ac.Port))
-		if err != nil {
-			return nil, errIncorrectNetAddr
-		}
-
-		// Encapsulate
-		return ipm.Encapsulate(udpm), nil
-
-	case "utp", "utp4", "utp6":
-		acc, ok := a.(*utp.Addr)
-		if !ok {
-			return nil, errIncorrectNetAddr
-		}
-
-		// Get UDP Addr
-		ac, ok := acc.Child().(*net.UDPAddr)
-		if !ok {
-			return nil, errIncorrectNetAddr
-		}
-
-		// Get IP Addr
-		ipm, err := FromIP(ac.IP)
-		if err != nil {
-			return nil, errIncorrectNetAddr
-		}
-
-		// Get UDP Addr
-		utpm, err := ma.NewMultiaddr(fmt.Sprintf("/udp/%d/utp", ac.Port))
-		if err != nil {
-			return nil, errIncorrectNetAddr
-		}
-
-		// Encapsulate
-		return ipm.Encapsulate(utpm), nil
-
-	case "ip", "ip4", "ip6":
-		ac, ok := a.(*net.IPAddr)
-		if !ok {
-			return nil, errIncorrectNetAddr
-		}
-		return FromIP(ac.IP)
-
-	case "ip+net":
-		ac, ok := a.(*net.IPNet)
-		if !ok {
-			return nil, errIncorrectNetAddr
-		}
-		return FromIP(ac.IP)
-
-	default:
-		return nil, fmt.Errorf("unknown network %v", a.Network())
+	p, err := cm.getAddrParser(a.Network())
+	if err != nil {
+		return nil, err
 	}
+
+	return p(a)
 }
 
 // ToNetAddr converts a Multiaddr to a net.Addr
 // Must be ThinWaist. acceptable protocol stacks are:
 // /ip{4,6}/{tcp, udp}
 func ToNetAddr(maddr ma.Multiaddr) (net.Addr, error) {
+	return defaultCodecs.ToNetAddr(maddr)
+}
+
+func (cm *CodecMap) ToNetAddr(maddr ma.Multiaddr) (net.Addr, error) {
+	protos := maddr.Protocols()
+	final := protos[len(protos)-1]
+
+	p, err := cm.getMaddrParser(final.Name)
+	if err != nil {
+		return nil, err
+	}
+
+	return p(maddr)
+}
+
+func parseBasicNetMaddr(maddr ma.Multiaddr) (net.Addr, error) {
 	network, host, err := DialArgs(maddr)
 	if err != nil {
 		return nil, err
@@ -143,6 +81,8 @@ func FromIP(ip net.IP) (ma.Multiaddr, error) {
 
 // DialArgs is a convenience function returning arguments for use in net.Dial
 func DialArgs(m ma.Multiaddr) (string, string, error) {
+	// TODO: find a 'good' way to eliminate the function.
+	// My preference is with a multiaddr.Format(...) function
 	if !IsThinWaist(m) {
 		return "", "", fmt.Errorf("%s is not a 'thin waist' address", m)
 	}
@@ -170,3 +110,91 @@ func DialArgs(m ma.Multiaddr) (string, string, error) {
 	}
 	return network, host, nil
 }
+
+func parseTcpNetAddr(a net.Addr) (ma.Multiaddr, error) {
+	ac, ok := a.(*net.TCPAddr)
+	if !ok {
+		return nil, errIncorrectNetAddr
+	}
+
+	// Get IP Addr
+	ipm, err := FromIP(ac.IP)
+	if err != nil {
+		return nil, errIncorrectNetAddr
+	}
+
+	// Get TCP Addr
+	tcpm, err := ma.NewMultiaddr(fmt.Sprintf("/tcp/%d", ac.Port))
+	if err != nil {
+		return nil, errIncorrectNetAddr
+	}
+
+	// Encapsulate
+	return ipm.Encapsulate(tcpm), nil
+}
+
+func parseUdpNetAddr(a net.Addr) (ma.Multiaddr, error) {
+	ac, ok := a.(*net.UDPAddr)
+	if !ok {
+		return nil, errIncorrectNetAddr
+	}
+
+	// Get IP Addr
+	ipm, err := FromIP(ac.IP)
+	if err != nil {
+		return nil, errIncorrectNetAddr
+	}
+
+	// Get UDP Addr
+	udpm, err := ma.NewMultiaddr(fmt.Sprintf("/udp/%d", ac.Port))
+	if err != nil {
+		return nil, errIncorrectNetAddr
+	}
+
+	// Encapsulate
+	return ipm.Encapsulate(udpm), nil
+}
+
+func parseUtpNetAddr(a net.Addr) (ma.Multiaddr, error) {
+	acc, ok := a.(*utp.Addr)
+	if !ok {
+		return nil, errIncorrectNetAddr
+	}
+
+	// Get UDP Addr
+	ac, ok := acc.Child().(*net.UDPAddr)
+	if !ok {
+		return nil, errIncorrectNetAddr
+	}
+
+	// Get IP Addr
+	ipm, err := FromIP(ac.IP)
+	if err != nil {
+		return nil, errIncorrectNetAddr
+	}
+
+	// Get UDP Addr
+	utpm, err := ma.NewMultiaddr(fmt.Sprintf("/udp/%d/utp", ac.Port))
+	if err != nil {
+		return nil, errIncorrectNetAddr
+	}
+
+	// Encapsulate
+	return ipm.Encapsulate(utpm), nil
+}
+
+func parseIpNetAddr(a net.Addr) (ma.Multiaddr, error) {
+	ac, ok := a.(*net.IPAddr)
+	if !ok {
+		return nil, errIncorrectNetAddr
+	}
+	return FromIP(ac.IP)
+}
+
+func parseIpPlusNetAddr(a net.Addr) (ma.Multiaddr, error) {
+	ac, ok := a.(*net.IPNet)
+	if !ok {
+		return nil, errIncorrectNetAddr
+	}
+	return FromIP(ac.IP)
+}

registry.go

@@ -0,0 +1,128 @@
+package manet
+
+import (
+	"fmt"
+	"net"
+	"sync"
+
+	ma "github.com/jbenet/go-multiaddr"
+)
+
+type FromNetAddrFunc func(a net.Addr) (ma.Multiaddr, error)
+type ToNetAddrFunc func(ma ma.Multiaddr) (net.Addr, error)
+
+var defaultCodecs *CodecMap
+
+func init() {
+	defaultCodecs = NewCodecMap()
+	defaultCodecs.RegisterNetCodec(tcpAddrSpec)
+	defaultCodecs.RegisterNetCodec(udpAddrSpec)
+	defaultCodecs.RegisterNetCodec(utpAddrSpec)
+	defaultCodecs.RegisterNetCodec(ip4AddrSpec)
+	defaultCodecs.RegisterNetCodec(ip6AddrSpec)
+}
+
+type CodecMap struct {
+	codecs       map[string]*NetCodec
+	addrParsers  map[string]FromNetAddrFunc
+	maddrParsers map[string]ToNetAddrFunc
+	lk           sync.Mutex
+}
+
+func NewCodecMap() *CodecMap {
+	return &CodecMap{
+		codecs:       make(map[string]*NetCodec),
+		addrParsers:  make(map[string]FromNetAddrFunc),
+		maddrParsers: make(map[string]ToNetAddrFunc),
+	}
+}
+
+type NetCodec struct {
+	// NetAddrNetworks is an array of strings that may be returned
+	// by net.Addr.Network() calls on addresses belonging to this type
+	NetAddrNetworks []string
+
+	// ProtocolName is the string value for Multiaddr address keys
+	ProtocolName string
+
+	// ParseNetAddr parses a net.Addr belonging to this type into a multiaddr
+	ParseNetAddr FromNetAddrFunc
+
+	// ConvertMultiaddr converts a multiaddr of this type back into a net.Addr
+	ConvertMultiaddr ToNetAddrFunc
+
+	// Protocol returns the multiaddr protocol struct for this type
+	Protocol ma.Protocol
+}
+
+func RegisterNetCodec(a *NetCodec) {
+	defaultCodecs.RegisterNetCodec(a)
+}
+
+func (cm *CodecMap) RegisterNetCodec(a *NetCodec) {
+	cm.lk.Lock()
+	defer cm.lk.Unlock()
+	cm.codecs[a.ProtocolName] = a
+	for _, n := range a.NetAddrNetworks {
+		cm.addrParsers[n] = a.ParseNetAddr
+	}
+
+	cm.maddrParsers[a.ProtocolName] = a.ConvertMultiaddr
+}
+
+var tcpAddrSpec = &NetCodec{
+	ProtocolName:     "tcp",
+	NetAddrNetworks:  []string{"tcp", "tcp4", "tcp6"},
+	ParseNetAddr:     parseTcpNetAddr,
+	ConvertMultiaddr: parseBasicNetMaddr,
+}
+
+var udpAddrSpec = &NetCodec{
+	ProtocolName:     "udp",
+	NetAddrNetworks:  []string{"udp", "udp4", "udp6"},
+	ParseNetAddr:     parseUdpNetAddr,
+	ConvertMultiaddr: parseBasicNetMaddr,
+}
+
+var utpAddrSpec = &NetCodec{
+	ProtocolName:     "utp",
+	NetAddrNetworks:  []string{"utp", "utp4", "utp6"},
+	ParseNetAddr:     parseUtpNetAddr,
+	ConvertMultiaddr: parseBasicNetMaddr,
+}
+
+var ip4AddrSpec = &NetCodec{
+	ProtocolName:     "ip4",
+	NetAddrNetworks:  []string{"ip4"},
+	ParseNetAddr:     parseIpNetAddr,
+	ConvertMultiaddr: parseBasicNetMaddr,
+}
+
+var ip6AddrSpec = &NetCodec{
+	ProtocolName:     "ip6",
+	NetAddrNetworks:  []string{"ip6"},
+	ParseNetAddr:     parseIpNetAddr,
+	ConvertMultiaddr: parseBasicNetMaddr,
+}
+
+func (cm *CodecMap) getAddrParser(net string) (FromNetAddrFunc, error) {
+	cm.lk.Lock()
+	defer cm.lk.Unlock()
+
+	parser, ok := cm.addrParsers[net]
+	if !ok {
+		return nil, fmt.Errorf("unknown network %v", net)
+	}
+	return parser, nil
+}
+
+func (cm *CodecMap) getMaddrParser(name string) (ToNetAddrFunc, error) {
+	cm.lk.Lock()
+	defer cm.lk.Unlock()
+	p, ok := cm.maddrParsers[name]
+	if !ok {
+		return nil, fmt.Errorf("network not supported: %s", name)
+	}
+
+	return p, nil
+}

registry_test.go

@@ -0,0 +1,50 @@
+package manet
+
+import (
+	"net"
+	"testing"
+
+	ma "github.com/jbenet/go-multiaddr"
+)
+
+func TestRegisterSpec(t *testing.T) {
+	cm := NewCodecMap()
+	myproto := &NetCodec{
+		ProtocolName:     "test",
+		NetAddrNetworks:  []string{"test", "iptest", "blahtest"},
+		ConvertMultiaddr: func(a ma.Multiaddr) (net.Addr, error) { return nil, nil },
+		ParseNetAddr:     func(a net.Addr) (ma.Multiaddr, error) { return nil, nil },
+	}
+
+	cm.RegisterNetCodec(myproto)
+
+	_, ok := cm.addrParsers["test"]
+	if !ok {
+		t.Fatal("myproto not properly registered")
+	}
+
+	_, ok = cm.addrParsers["iptest"]
+	if !ok {
+		t.Fatal("myproto not properly registered")
+	}
+
+	_, ok = cm.addrParsers["blahtest"]
+	if !ok {
+		t.Fatal("myproto not properly registered")
+	}
+
+	_, ok = cm.maddrParsers["test"]
+	if !ok {
+		t.Fatal("myproto not properly registered")
+	}
+
+	_, ok = cm.maddrParsers["iptest"]
+	if ok {
+		t.Fatal("myproto not properly registered")
+	}
+
+	_, ok = cm.maddrParsers["blahtest"]
+	if ok {
+		t.Fatal("myproto not properly registered")
+	}
+}