added metrics url

bots/bybot/main.go

@@ -5,9 +5,12 @@ import (
 	"fmt"
 	"log"
 	"math/rand"
+	"os"
 	"regexp"
 	"time"
 
+	"mcquay.me/exmo"
+
 	irc "github.com/fluffle/goirc/client"
 )
 
@@ -15,6 +18,16 @@ var host = flag.String("host", "localhost:6668", "irc server hostname")
 var channel = flag.String("channel", "#exmormon", "irc channel")
 
 func main() {
+	maddr := os.Getenv("ADDR")
+	if maddr == "" {
+		fmt.Fprintf(os.Stderr, "failed to set ADDR\n")
+		os.Exit(1)
+	}
+	if err := exmo.Metrics(maddr); err != nil {
+		fmt.Fprintf(os.Stderr, "can't http: %v\n", err)
+		os.Exit(1)
+	}
+
 	rand.Seed(time.Now().UnixNano())
 	flag.Parse()
 	log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)

bots/reddit/main.go

@@ -7,9 +7,12 @@ import (
 	"log"
 	"math/rand"
 	"net/http"
+	"os"
 	"regexp"
 	"time"
 
+	"mcquay.me/exmo"
+
 	irc "github.com/fluffle/goirc/client"
 )
 
@@ -18,6 +21,16 @@ var channel = flag.String("channel", "#exmormon", "irc channel")
 var top = flag.Int("top", 5, "number of top posts to use")
 
 func main() {
+	maddr := os.Getenv("ADDR")
+	if maddr == "" {
+		fmt.Fprintf(os.Stderr, "failed to set ADDR\n")
+		os.Exit(1)
+	}
+	if err := exmo.Metrics(maddr); err != nil {
+		fmt.Fprintf(os.Stderr, "can't http: %v\n", err)
+		os.Exit(1)
+	}
+
 	rand.Seed(time.Now().UnixNano())
 	flag.Parse()
 	log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)

exmo.go

@@ -0,0 +1,65 @@
+package exmo
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"log"
+	"net"
+	"net/http"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+func Metrics(addr string) error {
+	http.Handle("/metrics", prometheus.Handler())
+	h, p, err := net.SplitHostPort(addr)
+	if err != nil {
+		return err
+	}
+	var u string
+	if h != "" {
+		u = fmt.Sprintf("http://%v:%v/metrics", h, p)
+	} else {
+		u = fmt.Sprintf("http://localhost:%v/metrics", p)
+	}
+	e := make(chan error)
+
+	go func() {
+		err := http.ListenAndServe(addr, nil)
+		if err != nil {
+			log.Printf("%+v", err)
+		}
+		e <- err
+	}()
+
+	go func() {
+		t := 100 * time.Millisecond
+		for {
+			time.Sleep(t)
+			if t < time.Minute {
+				t = t * 2
+			}
+			if t > 5*time.Second {
+				e <- errors.New("timeout waiting for metrics server to start")
+			}
+
+			resp, err := http.Get(u)
+			if err != nil {
+				log.Printf("%+v", err)
+				continue
+			}
+			io.Copy(ioutil.Discard, resp.Body)
+			if resp.StatusCode != http.StatusOK {
+				log.Printf("%+v", resp.Status)
+			} else {
+				e <- nil
+				return
+			}
+		}
+	}()
+
+	return <-e
+}