From 24368747ab07e6cfc20848194724cb1dad60cfbf Mon Sep 17 00:00:00 2001
From: Guilhem Lettron <guilhem+github@lettron.fr>
Date: Thu, 23 Nov 2017 16:10:04 +0100
Subject: [PATCH] Use healthcheck for systemd watchdog

---
 cmd/traefik/healthcheck.go | 37 +++++++++++++++++++++----------------
 cmd/traefik/traefik.go     | 12 ++++++++++--
 2 files changed, 31 insertions(+), 18 deletions(-)

diff --git a/cmd/traefik/healthcheck.go b/cmd/traefik/healthcheck.go
index f0b0431d4..876d0d04f 100644
--- a/cmd/traefik/healthcheck.go
+++ b/cmd/traefik/healthcheck.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"crypto/tls"
+	"errors"
 	"fmt"
 	"net/http"
 	"os"
@@ -33,22 +34,7 @@ func runHealthCheck(traefikConfiguration *TraefikConfiguration) func() error {
 			os.Exit(1)
 		}
 
-		pingEntryPoint, ok := traefikConfiguration.EntryPoints[traefikConfiguration.Ping.EntryPoint]
-		if !ok {
-			pingEntryPoint = &configuration.EntryPoint{Address: ":8080"}
-		}
-
-		client := &http.Client{Timeout: 5 * time.Second}
-		protocol := "http"
-		if pingEntryPoint.TLS != nil {
-			protocol = "https"
-			tr := &http.Transport{
-				TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
-			}
-			client.Transport = tr
-		}
-
-		resp, errPing := client.Head(protocol + "://" + pingEntryPoint.Address + traefikConfiguration.Web.Path + "ping")
+		resp, errPing := healthCheck(traefikConfiguration.GlobalConfiguration)
 		if errPing != nil {
 			fmt.Printf("Error calling healthcheck: %s\n", errPing)
 			os.Exit(1)
@@ -62,3 +48,22 @@ func runHealthCheck(traefikConfiguration *TraefikConfiguration) func() error {
 		return nil
 	}
 }
+
+func healthCheck(globalConfiguration configuration.GlobalConfiguration) (*http.Response, error) {
+	pingEntryPoint, ok := globalConfiguration.EntryPoints[globalConfiguration.Ping.EntryPoint]
+	if !ok {
+		return nil, errors.New("missing ping entrypoint")
+	}
+
+	client := &http.Client{Timeout: 5 * time.Second}
+	protocol := "http"
+	if pingEntryPoint.TLS != nil {
+		protocol = "https"
+		tr := &http.Transport{
+			TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
+		}
+		client.Transport = tr
+	}
+
+	return client.Head(protocol + "://" + pingEntryPoint.Address + globalConfiguration.Web.Path + "ping")
+}
diff --git a/cmd/traefik/traefik.go b/cmd/traefik/traefik.go
index 75a4064d7..cad69e1fb 100644
--- a/cmd/traefik/traefik.go
+++ b/cmd/traefik/traefik.go
@@ -153,10 +153,12 @@ func run(globalConfiguration *configuration.GlobalConfiguration, configFile stri
 	svr := server.NewServer(*globalConfiguration)
 	svr.Start()
 	defer svr.Close()
+
 	sent, err := daemon.SdNotify(false, "READY=1")
 	if !sent && err != nil {
 		log.Error("Fail to notify", err)
 	}
+
 	t, err := daemon.SdWatchdogEnabled(false)
 	if err != nil {
 		log.Error("Problem with watchdog", err)
@@ -167,12 +169,18 @@ func run(globalConfiguration *configuration.GlobalConfiguration, configFile stri
 		safe.Go(func() {
 			tick := time.Tick(t)
 			for range tick {
-				if ok, _ := daemon.SdNotify(false, "WATCHDOG=1"); !ok {
-					log.Error("Fail to tick watchdog")
+				_, errHealthCheck := healthCheck(*globalConfiguration)
+				if globalConfiguration.Ping == nil || errHealthCheck == nil {
+					if ok, _ := daemon.SdNotify(false, "WATCHDOG=1"); !ok {
+						log.Error("Fail to tick watchdog")
+					}
+				} else {
+					log.Error(errHealthCheck)
 				}
 			}
 		})
 	}
+
 	svr.Wait()
 	log.Info("Shutting down")
 	logrus.Exit(0)