Add example daemon

example/daemons/number_printer.go

@@ -0,0 +1,53 @@
+package daemons
+
+import (
+	"log"
+	"math/rand"
+	"time"
+
+	"github.com/localhots/uberdaemon"
+)
+
+// NumberPrinter is a daemon that prints numbers once in a while.
+type NumberPrinter struct {
+	uberdaemon.BaseDaemon
+}
+
+// Startup sets up panic handler and starts enqueuing number printing jobs.
+func (n *NumberPrinter) Startup() {
+	n.HandlePanics(func() {
+		log.Println("Oh, crap!")
+	})
+
+	go n.enqueue()
+}
+
+// Shutdown is empty due to the lack of cleanup.
+func (n *NumberPrinter) Shutdown() {}
+
+func (n *NumberPrinter) enqueue() {
+	for {
+		select {
+		case <-n.ShutdownRequested():
+			return
+		default:
+		}
+
+		// Generate a random number between 1000 and 9999 and print it
+		num := 1000 + rand.Intn(9000)
+		n.Process(n.makeActor(num))
+
+		// Sleep for a second or less
+		time.Sleep(time.Duration(rand.Intn(1000)) * time.Millisecond)
+	}
+}
+
+func (n *NumberPrinter) makeActor(num int) uberdaemon.Actor {
+	return func() {
+		if rand.Intn(20) == 0 {
+			panic("Noooooooooo!")
+		}
+
+		log.Println("NumberPrinter says", num)
+	}
+}

example/main.go

@@ -0,0 +1,36 @@
+package main
+
+import (
+	"flag"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/localhots/uberdaemon"
+	"github.com/localhots/uberdaemon/example/daemons"
+)
+
+func main() {
+	var debug bool
+	flag.BoolVar(&debug, "v", false, "Verbose mode")
+	flag.Parse()
+	if !debug {
+		log.SetOutput(ioutil.Discard)
+	}
+
+	uberd := uberdaemon.New()
+	uberd.AddDaemon(&daemons.NumberPrinter{})
+	uberd.Start()
+	defer uberd.Stop()
+
+	sig := make(chan os.Signal)
+	signal.Notify(sig, os.Interrupt, syscall.SIGTERM)
+
+	for s := range sig {
+		if s == os.Interrupt {
+			return
+		}
+	}
+}