add args: startup_timeout for kubernetes plugin (#7068)

Signed-off-by: mangoyhuang <mangoyhuang@tencent.com>
Co-authored-by: mangoyhuang <mangoyhuang@tencent.com>

plugin/kubernetes/setup.go

@@ -7,6 +7,7 @@ import (
 	"slices"
 	"strconv"
 	"strings"
+	"time"
 
 	"github.com/coredns/caddy"
 	"github.com/coredns/coredns/core/dnsserver"
@@ -112,6 +113,7 @@ func ParseStanza(c *caddy.Controller) (*Kubernetes, error) {
 
 	k8s.Upstream = upstream.New()
 
+	k8s.startupTimeout = time.Second * 5
 	for c.NextBlock() {
 		switch c.Val() {
 		case "endpoint_pod_names":
@@ -231,6 +233,17 @@ func ParseStanza(c *caddy.Controller) (*Kubernetes, error) {
 			k8s.ClientConfig = config
 		case "multicluster":
 			k8s.opts.multiclusterZones = plugin.OriginsFromArgsOrServerBlock(c.RemainingArgs(), []string{})
+		case "startup_timeout":
+			args := c.RemainingArgs()
+			if len(args) == 0 {
+				return nil, c.ArgErr()
+			} else {
+				var err error
+				k8s.startupTimeout, err = time.ParseDuration(args[0])
+				if err != nil {
+					return nil, fmt.Errorf("failed to parse startup_timeout: %v, %s", args[0], err)
+				}
+			}
 		default:
 			return nil, c.Errf("unknown property '%s'", c.Val())
 		}