set num-nodes flag automatically (#16176)

Co-authored-by: upodroid <upodroid@users.noreply.github.com>

tests/e2e/pkg/tester/skip_regex.go

@@ -26,7 +26,7 @@ import (
 )
 
 const (
-	skipRegexBase = "\\[Slow\\]|\\[Serial\\]|\\[Disruptive\\]|\\[Flaky\\]|\\[Feature:.+\\]|nfs|NFS|Gluster"
+	skipRegexBase = "\\[Slow\\]|\\[Serial\\]|\\[Disruptive\\]|\\[Flaky\\]|\\[Feature:.+\\]|nfs|NFS|Gluster|NodeProblemDetector"
 )
 
 func (t *Tester) setSkipRegexFlag() error {
@@ -81,6 +81,8 @@ func (t *Tester) setSkipRegexFlag() error {
 		skipRegex += "|same.hostPort.but.different.hostIP.and.protocol"
 		// https://github.com/cilium/cilium/issues/9207
 		skipRegex += "|serve.endpoints.on.same.port.and.different.protocols"
+		// https://github.com/kubernetes/kubernetes/blob/418ae605ec1b788d43bff7ac44af66d8b669b833/test/e2e/network/networking.go#L135
+		skipRegex += "|should.check.kube-proxy.urls"
 
 		if isPre28 {
 			// These may be fixed in Cilium 1.13 but skipping for now

tests/e2e/pkg/tester/tester.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"strconv"
 	"strings"
 
 	"github.com/octago/sflags/gen/gpflag"
@@ -187,11 +188,6 @@ func (t *Tester) addNodeIG() error {
 		return err
 	}
 
-	// Skip this function for non gce clusters
-	if cluster.Spec.LegacyCloudProvider != "gce" {
-		return nil
-	}
-
 	igs, err := kops.GetInstanceGroups("kops", cluster.Name, nil)
 	if err != nil {
 		return err
@@ -203,6 +199,15 @@ func (t *Tester) addNodeIG() error {
 			ig = v
 		}
 	}
+	numNodes := int(*ig.Spec.MaxSize) // we assume that MinSize = Maxsize, this is true for e2e testing
+	klog.Infof("Setting -num-nodes=%v", numNodes)
+	t.TestArgs += " -num-nodes=" + strconv.Itoa(numNodes)
+
+	// Skip the rest of this function for non gce clusters
+	if cluster.Spec.LegacyCloudProvider != "gce" {
+		return nil
+	}
+
 	nodeTag := gce.TagForRole(cluster.ObjectMeta.Name, unversioned.InstanceGroupRoleNode)
 	klog.Infof("Setting --node-tag=%s", nodeTag)
 	t.TestArgs += " --node-tag=" + nodeTag