// subscribe all websocket clients to stream data
// eg subscribe;3;stdout
func wseventSubscribe(s *server, options string) error {
args := strings.Split(options, ";")
if len(args) != 2 {
return errors.New("subscribe requires 2 args")
}
idstr := args[0]
streamname := args[1]
c, err := getCmd(s, idstr)
if err != nil {
return err
}
var stream liblush.OutStream
switch streamname {
case "stdout":
stream = c.Stdout()
case "stderr":
stream = c.Stderr()
default:
return errors.New("unknown stream: " + streamname)
}
// proxy stream data
w := newPrefixedWriter(&s.ctrlclients, []byte("stream;"+idstr+";"+streamname+";"))
// do not close websocket stream when command exits
wc := newNopWriteCloser(w)
stream.Peeker().AddWriter(wc)
return nil
}
func connectCmdsById(s *server, fromId, toId liblush.CmdId, streamname string) error {
var stream liblush.OutStream
var to, from liblush.Cmd
from = s.session.GetCommand(fromId)
if from == nil {
return errors.New("unknown command in from")
}
switch streamname {
case "stdout":
stream = from.Stdout()
case "stderr":
stream = from.Stderr()
default:
return errors.New("unknown stream")
}
if toId == 0 {
return disconnectStream(stream)
}
to = s.session.GetCommand(toId)
if to == nil {
return errors.New("unknown command in to")
}
if pipedcmd(stream) != nil {
// not strictly necessary but makes for simpler API. service to the
// user! because that is how we roll. EaaS.
return errors.New("already connected to another command")
}
stream.SetListener(to.Stdin())
return nil
}
func disconnectStream(stream liblush.OutStream) error {
var fwd liblush.Cmd
fwd = pipedcmd(stream)
if fwd == nil {
return errors.New("no connected command found")
}
stream.SetListener(liblush.Devnull)
return nil
}
func handleWsStream(ctx *web.Context, idstr, streamname string) error {
id, _ := liblush.ParseCmdId(idstr)
s := ctx.User.(*server)
c := s.session.GetCommand(id)
if c == nil {
return web.WebError{404, "no such command: " + idstr}
}
var stream liblush.OutStream
switch streamname {
case "stdout":
stream = c.Stdout()
case "stderr":
stream = c.Stderr()
default:
return web.WebError{400, "No such stream: " + streamname}
}
stream.Peeker().AddWriter(ctx.WebsockConn)
buf := make([]byte, 1)
ctx.WebsockConn.Read(buf)
return nil
}
// return command that this stream pipes to, if any
func pipedcmd(outs liblush.OutStream) liblush.Cmd {
return iscmd(outs.GetListener())
}