main.go

package main

import (
	"fmt"
	"github.com/cactus/gologit"
	"github.com/cactus/slurpy/slurpylog"
	flags "github.com/jessevdk/go-flags"
	"os"
	"os/signal"
	"runtime"
	"strconv"
	"strings"
	"syscall"
)

const VERSION = "0.0.1"

func chanByteReader(msg *slurpylog.SyslogMsg) {
	facName, _ := slurpylog.FacilityGetName(msg.Facility)
	sevName, _ := slurpylog.SeverityGetName(msg.Severity)
	fmt.Printf(
		"%s.%s %s\n",
		strings.ToLower(facName),
		strings.ToLower(sevName),
		msg.Msg)
}

func main() {
	var gmx int
	if gmxEnv := os.Getenv("GOMAXPROCS"); gmxEnv != "" {
		gmx, _ = strconv.Atoi(gmxEnv)
	} else {
		gmx = runtime.NumCPU()
	}
	runtime.GOMAXPROCS(gmx)

	// command line flags
	var opts struct {
		BindTCP string `short:"t" long:"listen-tcp" default:"" description:"TCP address:port to listen to"`
		BindUDP string `short:"u" long:"listen-udp" default:"" description:"UDP address:port to listen to"`
		Verbose bool   `short:"v" long:"verbose" description:"Show verbose (debug) log level output"`
		Version bool   `short:"V" long:"version" description:"print version and exit"`
	}

	// parse said flags
	_, err := flags.Parse(&opts)
	if err != nil {
		if e, ok := err.(*flags.Error); ok {
			if e.Type == flags.ErrHelp {
				os.Exit(0)
			}
		}
		os.Exit(1)
	}

	if opts.Version {
		fmt.Printf("slurpy-%s (%s,%s-%s)\n", VERSION, runtime.Version(), runtime.Compiler, runtime.GOARCH)
		os.Exit(0)
	}

	if opts.BindTCP == "" && opts.BindUDP == "" {
		fmt.Println("No listen ports defined. Exiting.")
		os.Exit(1)
	}

	// set logger debug level and start toggle on signal handler
	logger := gologit.Logger
	logger.Set(opts.Verbose)
	logger.Debugln("Debug logging enabled")
	logger.ToggleOnSignal(syscall.SIGUSR1)

	if opts.BindTCP != "" {
		gologit.Println("Starting tcp server on", opts.BindTCP)
		tcpsrv, err := slurpylog.ListenTCP("tcp", opts.BindTCP, chanByteReader)
		if err != nil {
			gologit.Fatal(err)
		}
		defer tcpsrv.Close()
	}

	if opts.BindUDP != "" {
		gologit.Println("Starting udp server on", opts.BindUDP)
		udpsrv, err := slurpylog.ListenUDP("udp", opts.BindUDP, chanByteReader)
		if err != nil {
			gologit.Fatal(err)
		}
		defer udpsrv.Close()
	}
	closeSig := make(chan os.Signal, 1)
	signal.Notify(closeSig, os.Interrupt)
	s := <-closeSig
	gologit.Printf("got signal: %s. Closing.\n", s)
	return
}