func cmdDaemon(c *cli.Context) {
app := libswarm.NewServer()
app.OnLog(func(args ...string) error {
log.Printf("%s\n", strings.Join(args, " "))
return nil
})
app.OnError(func(args ...string) error {
Fatalf("Fatal: %v", strings.Join(args[:1], ""))
return nil
})
back := backends.New()
if len(c.Args()) == 0 {
names, err := back.Ls()
if err != nil {
Fatalf("ls: %v", err)
}
fmt.Println(strings.Join(names, "\n"))
return
}
var previousInstanceR libswarm.Receiver
// FIXME: refactor into a Pipeline
for idx, backendArg := range c.Args() {
bName, bArgs, err := parseCmd(backendArg)
if err != nil {
Fatalf("parse: %v", err)
}
_, backend, err := back.Attach(bName)
if err != nil {
Fatalf("%s: %v\n", bName, err)
}
instance, err := backend.Spawn(bArgs...)
if err != nil {
Fatalf("spawn %s: %v\n", bName, err)
}
instanceR, instanceW, err := instance.Attach("")
if err != nil {
Fatalf("attach: %v", err)
}
go func(r libswarm.Receiver, w libswarm.Sender, idx int) {
if r != nil {
libswarm.Copy(w, r)
}
w.Close()
}(previousInstanceR, instanceW, idx)
if err := instance.Start(); err != nil {
Fatalf("start: %v", err)
}
previousInstanceR = instanceR
}
_, err := libswarm.Copy(app, previousInstanceR)
if err != nil {
Fatalf("copy: %v", err)
}
}
func (a *aggregator) attach(name string, ret libswarm.Sender) error {
if name != "" {
// TODO: implement this?
return fmt.Errorf("attaching to a child is not implemented")
}
if _, err := ret.Send(&libswarm.Message{Verb: libswarm.Ack, Ret: a.server}); err != nil {
return err
}
var copies sync.WaitGroup
for _, b := range a.backends {
r, _, err := b.Attach("")
if err != nil {
return err
}
copies.Add(1)
go func() {
log.Printf("copying output from %#v\n", b)
libswarm.Copy(ret, r)
log.Printf("finished output from %#v\n", b)
copies.Done()
}()
}
copies.Wait()
return nil
}
func Task(f func(in libswarm.Receiver, out libswarm.Sender)) libswarm.Sender {
var running bool
var l sync.RWMutex
inR, inW := libswarm.Pipe()
outR, outW := libswarm.Pipe()
obj := libswarm.NewServer()
obj.OnVerb(libswarm.Attach, libswarm.Handler(func(msg *libswarm.Message) error {
msg.Ret.Send(&libswarm.Message{Verb: libswarm.Ack, Ret: inW})
fmt.Printf("copying task output from %#v to %#v\n", outR, msg.Ret)
defer fmt.Printf("(DONE) copying task output from %#v to %#v\n", outR, msg.Ret)
libswarm.Copy(msg.Ret, outR)
return nil
}))
obj.OnVerb(libswarm.Start, libswarm.Handler(func(msg *libswarm.Message) error {
l.RLock()
r := running
l.RUnlock()
if r {
return fmt.Errorf("already running")
}
l.Lock()
go f(inR, outW)
running = true
l.Unlock()
msg.Ret.Send(&libswarm.Message{Verb: libswarm.Ack})
return nil
}))
return obj
}
func Simulator() libswarm.Sender {
s := libswarm.NewServer()
s.OnVerb(libswarm.Spawn, libswarm.Handler(func(ctx *libswarm.Message) error {
containers := ctx.Args
instance := utils.Task(func(in libswarm.Receiver, out libswarm.Sender) {
libswarm.AsClient(out).Log("[simulator] starting\n")
s := libswarm.NewServer()
s.OnVerb(libswarm.Ls, libswarm.Handler(func(msg *libswarm.Message) error {
libswarm.AsClient(out).Log("[simulator] generating fake list of objects...\n")
libswarm.AsClient(msg.Ret).Set(containers...)
return nil
}))
libswarm.Copy(s, in)
})
ctx.Ret.Send(&libswarm.Message{Verb: libswarm.Ack, Ret: instance})
return nil
}))
return s
}
// Spawn will return a new instance as the Ret channel of the message sent back
func (dbg *debug) spawn(msg *libswarm.Message) (err error) {
// By sending back a task, libswarm will run the function with the in and out arguments
// set to the services present before and after this one in the pipeline.
instance := utils.Task(func(in libswarm.Receiver, out libswarm.Sender) {
// Setup our channels
dbg.out = out
// Set up the debug interceptor
dbg.service.Catchall(libswarm.Handler(dbg.catchall))
// Copy everything from the receiver to our service. By copying like this in the task
// we can use the catchall handler instead of handling the message here.
libswarm.Copy(dbg.service, in)
})
// Inform the system of our new instance
msg.Ret.Send(&libswarm.Message{
Verb: libswarm.Ack,
Ret: instance,
})
return
}