func dial(x *cli.Context) *client.Client {
var dialAddr string
switch {
case x.IsSet("dial"):
dialAddr = x.String("dial")
case os.Getenv("CIRCUIT") != "":
buf, err := ioutil.ReadFile(os.Getenv("CIRCUIT"))
if err != nil {
fatalf("circuit environment file %s is not readable: %v", os.Getenv("CIRCUIT"), err)
}
dialAddr = strings.TrimSpace(string(buf))
default:
buf, err := ioutil.ReadFile(".circuit")
if err != nil {
fatalf("no dial address available; use flag -d or set CIRCUIT to a file name")
}
dialAddr = strings.TrimSpace(string(buf))
}
defer func() {
if r := recover(); r != nil {
fatalf("addressed server is gone or a newer one is in place")
}
}()
return client.Dial(dialAddr)
}
func server(c *cli.Context) {
println("CIRCUIT 2014 gocircuit.org")
var err error
if c.Bool("docker") {
cmd, err := docker.Init()
if err != nil {
log.Fatalf("cannot use docker: %v", err)
}
log.Printf("Enabling docker elements, using %s", cmd)
}
// parse arguments
var tcpaddr = parseAddr(c) // server bind address
var join n.Addr // join address of another circuit server
if c.IsSet("join") {
if join, err = n.ParseAddr(c.String("join")); err != nil {
log.Fatalf("join address does not parse (%s)", err)
}
}
var multicast = parseDiscover(c)
// server instance working directory
var varDir string
if !c.IsSet("var") {
varDir = path.Join(os.TempDir(), fmt.Sprintf("%s-%%W-P%04d", n.Scheme, os.Getpid()))
} else {
varDir = c.String("var")
}
// start circuit runtime
addr := load(tcpaddr, varDir, readkey(c))
// tissue + locus
kin, xkin, rip := tissue.NewKin()
xlocus := locus.NewLocus(kin, rip)
// joining
switch {
case join != nil:
kin.ReJoin(join)
case multicast != nil:
log.Printf("Using UDP multicast discovery on address %s", multicast.String())
go assemble.NewAssembler(addr, multicast).AssembleServer(
func(joinAddr n.Addr) {
kin.ReJoin(joinAddr)
},
)
default:
log.Println("Singleton server.")
}
circuit.Listen(tissue.ServiceName, xkin)
circuit.Listen(LocusName, xlocus)
<-(chan int)(nil)
}
func parseDiscover(c *cli.Context) *net.UDPAddr {
var src string
if c.IsSet("discover") {
src = c.String("discover")
} else if os.Getenv("CIRCUIT_DISCOVER") != "" {
src = os.Getenv("CIRCUIT_DISCOVER")
} else {
return nil
}
multicast, err := net.ResolveUDPAddr("udp", src)
if err != nil {
log.Fatalf("udp multicast address for discovery and assembly does not parse (%s)", err)
}
return multicast
}
func readkey(x *cli.Context) (key []byte) {
var hmac string
switch {
case x.IsSet("hmac"):
hmac = x.String("hmac")
case os.Getenv("CIRCUIT_HMAC") != "":
hmac = os.Getenv("CIRCUIT_HMAC")
default:
return nil
}
b64, err := ioutil.ReadFile(hmac)
if err != nil {
fatalf("problem reading private key file (%s): %v", hmac, err)
}
if key, err = base64.StdEncoding.DecodeString(string(b64)); err != nil {
fatalf("problem decoding base64 private key: %v", err)
}
return
}
func dial(x *cli.Context) *client.Client {
switch {
case x.IsSet("dial"):
defer func() {
if r := recover(); r != nil {
fatalf("addressed server is gone or authentication failed")
}
}()
return client.Dial(x.String("dial"), readkey(x))
case x.IsSet("discover"):
defer func() {
if r := recover(); r != nil {
fatalf("multicast address is unresponsive or authentication failed")
}
}()
return client.DialDiscover(x.String("discover"), readkey(x))
case os.Getenv("CIRCUIT") != "":
buf, err := ioutil.ReadFile(os.Getenv("CIRCUIT"))
if err != nil {
fatalf("circuit environment file %s is not readable: %v", os.Getenv("CIRCUIT"), err)
}
defer func() {
if r := recover(); r != nil {
fatalf("addressed server is gone or authentication failed")
}
}()
return client.Dial(strings.TrimSpace(string(buf)), readkey(x))
case os.Getenv("CIRCUIT_DISCOVER") != "":
defer func() {
if r := recover(); r != nil {
fatalf("multicast address is unresponsive or authentication failed")
}
}()
return client.DialDiscover(os.Getenv("CIRCUIT_DISCOVER"), readkey(x))
}
fatalf("no dial or discovery addresses available; use -dial or -discover")
panic(0)
}
func parseAddr(c *cli.Context) *net.TCPAddr {
switch {
case c.IsSet("addr"):
addr, err := net.ResolveTCPAddr("tcp", c.String("addr"))
if err != nil {
log.Fatalf("resolve %s (%s)\n", addr, err)
}
if len(addr.IP) == 0 {
addr.IP = net.IPv4zero
}
return addr
case c.IsSet("if"):
ifc, err := net.InterfaceByName(c.String("if"))
if err != nil {
log.Fatalf("interface %s not found (%v)", c.String("if"), err)
}
addrs, err := ifc.Addrs()
if err != nil {
log.Fatalf("interface address cannot be retrieved (%v)", err)
}
if len(addrs) == 0 {
log.Fatalf("no addresses associated with this interface")
}
for _, a := range addrs { // pick the IPv4 one
ipn := a.(*net.IPNet)
if ipn.IP.To4() == nil {
continue
}
return &net.TCPAddr{IP: ipn.IP}
}
log.Fatal("specified interface has no IPv4 addresses")
default:
log.Fatal("either an -addr or an -if option is required to start a server")
}
panic(0)
}
func server(c *cli.Context) {
println("CIRCUIT 2014 gocircuit.org")
log.Println("Starting circuit server")
// parse arguments
if !c.IsSet("addr") {
log.Fatal("server network address not given; use -addr")
}
var err error
var join n.Addr
if c.IsSet("join") {
if join, err = n.ParseAddr(c.String("join")); err != nil {
log.Fatalf("join address does not parse (%s)", err)
}
}
var mutexDir string
if !c.IsSet("mutex") {
mutexDir = path.Join(os.TempDir(), fmt.Sprintf("%s-%%W-P%04d", n.Scheme, os.Getpid()))
} else {
mutexDir = c.String("mutex")
}
// start circuit runtime
load(c.String("addr"), mutexDir)
// kinfolk join
var xjoin circuit.PermX
dontPanic(func() {
xjoin = circuit.Dial(join, KinfolkName)
}, "join")
// locus
kin, xkin, kinJoin, kinLeave := kinfolk.NewKin(xjoin)
xlocus := locus.NewLocus(kin, kinJoin, kinLeave)
circuit.Listen(KinfolkName, xkin)
circuit.Listen(LocusName, xlocus)
<-(chan int)(nil)
}