circolog/main.go

package main

import (
	"container/ring"
	"flag"
	"fmt"
	"net/http"
	"os"
	"strconv"

	syslog "gopkg.in/mcuadros/go-syslog.v2"
	"gopkg.in/mcuadros/go-syslog.v2/format"
)

var circbuf *ring.Ring

func syslogdHandler(channel syslog.LogPartsChannel) {
	for logParts := range channel {
		fmt.Println(logParts)
		circbuf.Value = logParts
		circbuf = circbuf.Next()
	}
}

func httpHandler(w http.ResponseWriter, r *http.Request) {
	circbuf.Do(func(x interface{}) {
		if x == nil {
			return
		}
		logmsg := x.(format.LogParts)
		if logmsg["message"] == nil {
			return
		}
		c := logmsg["message"].(string)
		w.Write([]byte(c))
		w.Write([]byte("\n"))
	})
}
func main() {
	syslogSocketPath := flag.String("syslogd-socket", "", "The socket to listen to syslog addresses")
	// dumpSocketPath := flag.String("dump-socket", "/run/buffer.sock", "The socket that user will connect to in order to receive logs")
	bufsize := flag.Int("buffer-size", 1000, "Number of messages to keep")
	UDPPort := flag.Int("log-port", 9514, "UDP port where to listen for syslog messages")
	TCPPort := flag.Int("query-port", 9080, "TCP port where to listen for queries from the buffer")
	address := flag.String("addr", "127.0.0.1", "Address to bind to")
	flag.Parse()
	if *TCPPort > 65535 || *TCPPort < 1 {
		fmt.Fprintf(os.Stderr, "Error: selected query-port is out of bounds: %d\n", *TCPPort)
		os.Exit(1)
	}
	if *UDPPort > 65535 || *UDPPort < 1 {
		fmt.Fprintf(os.Stderr, "Error: selected log-port is out of bounds: %d\n", *UDPPort)
		os.Exit(1)
	}

	channel := make(chan format.LogParts)
	handler := syslog.NewChannelHandler(channel)

	server := syslog.NewServer()
	server.SetFormat(syslog.RFC5424)
	server.SetHandler(handler)
	if *syslogSocketPath != "" {
		server.ListenUnixgram(*syslogSocketPath)
		fmt.Printf("Binding socket `%s` [syslog]\n", *syslogSocketPath)
		os.Exit(2)
	} else {
		addr := *address + ":" + strconv.Itoa(*UDPPort)
		fmt.Printf("Binding address `%s` [syslog]\n", addr)
		server.ListenUDP(addr)
	}
	circbuf = ring.New(*bufsize)
	server.Boot()
	go syslogdHandler(channel)

	http.HandleFunc("/", httpHandler)
	listenPortFmt := ":" + strconv.Itoa(*TCPPort)
	fmt.Printf("Binding address `%s` [http]\n", listenPortFmt)
	http.ListenAndServe(listenPortFmt, nil)

	server.Wait()
}