implemented dealing of SIGHUP for wwclient

cmd/wwclient/wwclient.go

@@ -8,9 +8,12 @@ import (
 	"net/http"
 	"os"
 	"os/exec"
+	"os/signal"
 	"strings"
+	"syscall"
 	"time"
 
+	"github.com/google/uuid"
 	"github.com/hpcng/warewulf/internal/pkg/warewulfconf"
 	"github.com/hpcng/warewulf/internal/pkg/wwlog"
 	"github.com/talos-systems/go-smbios/smbios"
@@ -68,7 +71,6 @@ func main() {
 			ExpectContinueTimeout: 1 * time.Second,
 		},
 	}
-
 	smbiosDump, err := smbios.New()
 	if err != nil {
 		wwlog.Printf(wwlog.ERROR, "Could not get SMBIOS info: %s\n", err)
@@ -93,14 +95,34 @@ func main() {
 
 	wwid := strings.Split(wwid_tmp[1], " ")[0]
 
+	// listen on SIGHUP
+	sigs := make(chan os.Signal)
+	signal.Notify(sigs, syscall.SIGHUP)
+
+	go func() {
+		for sig := range sigs {
+			log.Printf("Received SIGNAL: %s\n", sig)
+			updateSystem(webclient, conf.Ipaddr, conf.Warewulf.Port, wwid, tag, localUUID)
+		}
+	}()
+
 	for {
+		updateSystem(webclient, conf.Ipaddr, conf.Warewulf.Port, wwid, tag, localUUID)
+
+		if conf.Warewulf.UpdateInterval > 0 {
+			time.Sleep(time.Duration(conf.Warewulf.UpdateInterval*1000) * time.Millisecond)
+		} else {
+			time.Sleep(30000 * time.Millisecond * 1000)
+		}
+	}
+}
+
+func updateSystem(webclient *http.Client, ipaddr string, port int, wwid string, tag string, localUUID uuid.UUID) {
 	var resp *http.Response
 	counter := 0
-
 	for {
 		var err error
-
-			getString := fmt.Sprintf("http://%s:%d/overlay-runtime/%s?assetkey=%s&uuid=%s", conf.Ipaddr, conf.Warewulf.Port, wwid, tag, localUUID)
+		getString := fmt.Sprintf("http://%s:%d/overlay-runtime/%s?assetkey=%s&uuid=%s", ipaddr, port, wwid, tag, localUUID)
 		resp, err = webclient.Get(getString)
 		if err == nil {
 			break
@@ -113,16 +135,13 @@ func main() {
 			}
 			counter++
 		}
-
 		time.Sleep(1000 * time.Millisecond)
 	}
-
 	if resp.StatusCode != 200 {
 		log.Printf("Not updating runtime overlay, got status code: %d\n", resp.StatusCode)
 		time.Sleep(60000 * time.Millisecond)
-			continue
+		return
 	}
-
 	log.Printf("Updating system\n")
 	command := exec.Command("/bin/sh", "-c", "gzip -dc | cpio -iu")
 	command.Stdin = resp.Body
@@ -130,11 +149,4 @@ func main() {
 	if err != nil {
 		log.Printf("ERROR: Failed running CPIO: %s\n", err)
 	}
-
-		if conf.Warewulf.UpdateInterval > 0 {
-			time.Sleep(time.Duration(conf.Warewulf.UpdateInterval*1000) * time.Millisecond)
-		} else {
-			time.Sleep(30000 * time.Millisecond * 1000)
-		}
-	}
 }