A trivial syslog-to-journal implementation

syslog-to-journal.go

package main

import (
	"fmt"
	"io"
	"net/http"
	"time"

	"github.com/jeromer/syslogparser"

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

func makeRequest() *io.PipeWriter {
	pipeR, pipeW := io.Pipe()
	r, err := http.NewRequest("POST", "http://127.0.0.1:19532/upload", pipeR)
	if err != nil {
		panic(err)
	}

	r.ContentLength = -1
	r.Header.Set("Content-Type", "application/vnd.fdo.journal")

	go func() {
		_, err := http.DefaultClient.Do(r)
		if err != nil {
			panic(err)
		}
		panic("request died")
	}()

	return pipeW
}

func worker(c chan syslogparser.LogParts) {
	pipeW := makeRequest()

	for entry := range c {
		uploadLogEntry(entry, pipeW)
	}
}

func main() {
	channel := make(syslog.LogPartsChannel)
	handler := syslog.NewChannelHandler(channel)

	server := syslog.NewServer()
	server.SetFormat(syslog.Automatic)
	server.SetHandler(handler)
	err := server.ListenUDP("0.0.0.0:514")
	if err != nil {
		panic(err)
	}
	err = server.Boot()
	if err != nil {
		panic(err)
	}

	go worker(channel)

	server.Wait()
	fmt.Println("Done waiting.")
}

func uploadLogEntry(logParts syslogparser.LogParts, w io.Writer) {
	_, err := io.WriteString(w, fmt.Sprintf("__REALTIME_TIMESTAMP=%d\nMESSAGE=%s\nPRIORITY=%d\nSYSLOG_FACILITY=%d\nSYSLOG_IDENTIFIER=%s\n_HOSTNAME=%s\n\n", getTimestamp(logParts["timestamp"].(time.Time)), logParts["content"], logParts["severity"], logParts["facility"], logParts["tag"], logParts["hostname"]))
	if err != nil {
		panic(err)
	}
}

func getTimestamp(t time.Time) int64 {
	ns := t.UnixNano()
	return ns / 1000
}