direttoforo/cmd/direttoforo/main.go

package main

import (
	"flag"
	"fmt"
	"net"
	"os"
	"os/signal"
	"time"

	"git.lattuga.net/boyska/direttoforo/liquidsoap"
	"git.lattuga.net/boyska/direttoforo/uiserver"
)

type State struct {
	Streams map[string]liquidsoap.Stream
}

func NewState() State {
	s := State{}
	s.Streams = make(map[string]liquidsoap.Stream)
	return s
}

func main() {
	liqfile := flag.String("liq", "foo.liq", "Path to liquidsoap script to run")
	bindpath := flag.String("bindpath", "/var/lib/direttoforo/ui.sock", "UNIX domain socket path for UIs")
	flag.Parse()

	state := NewState()

	netUIsock, err := net.Listen("unix", *bindpath)
	if err != nil {
		fmt.Fprintln(os.Stderr, "error binding UI socket!")
		fmt.Fprintln(os.Stderr, err)
		os.Exit(1)
		return
	}
	netUI := uiserver.NewNetUI(&state)
	go func() {
		err := netUI.Run(netUIsock)
		if err != nil {
			fmt.Fprintln(os.Stderr, "NetUI error", err)
		}
	}()

	killLs := make(chan struct{}) // when it is closed, liquidsoap will die
	killed := make(chan os.Signal, 1)
	signal.Notify(killed, os.Interrupt) // ctrl-c
	output, exit, err := liquidsoap.RunLiquidsoap(*liqfile, killLs)
	if err != nil {
		fmt.Fprintln(os.Stderr, "Error spawning liquidsoap", err)
		os.Exit(1)
	}

	go func(log <-chan liquidsoap.Output) {
		for {
			msg := <-log
			if msg.Msg != "" && msg.Level < 3 {
				fmt.Println("msg", msg)
			}
		}
	}(output)

	go func() {
		tick := time.Tick(3 * time.Second)
		for {
			<-tick
			t, err := liquidsoap.NewTelnet("localhost", 1234)
			if err != nil {
				fmt.Println("telnet connection errored", err)
				continue
			}
			t.Conn.SetDeadline(time.Now().Add(3 * time.Second))
			outs, err := t.Outputs()
			if err != nil {
				fmt.Println("telnet cmd errored", err)
				continue
			}
			changed := false
			for name, newstream := range outs {
				if stream, exists := state.Streams[name]; exists {
					if newstream != stream {
						state.Streams[name] = newstream
						changed = true
					}
				} else {
					state.Streams[name] = newstream
					changed = true
				}
			}
			t.Close()
			if changed {
				fmt.Println("state=", state)
				netUI.Update()
			}
		}
	}()

	for {
		select {
		case how := <-exit: // liquidsoap exits
			if !how.Success() {
				fmt.Fprintln(os.Stderr, "liquidsoap terminated,", how.Err)
				netUI.Close()
				os.Exit(1)
			}
			os.Exit(0)
		case <-killed: // we receive a SIGINT: ask liquidsoap to die is enough
			netUI.Close()
			close(killLs)
			fmt.Println("Closed by user interaction, waiting for liquidsoap to exit")
			// TODO: schedule a more aggressive SIGKILL if liquidsoap doesn't
			// exit soon
		}
	}

}