From 79be7c45183feacb9c5817af9f5a8116f46c6e91 Mon Sep 17 00:00:00 2001
From: Traian Schiau <traian_schiau@epam.com>
Date: Tue, 6 Jun 2023 13:25:51 +0300
Subject: [PATCH] [webhook/workload] Limit the number of variable count podSets

---
 pkg/webhooks/workload_webhook.go      | 11 ++++++++++-
 pkg/webhooks/workload_webhook_test.go | 11 +++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/pkg/webhooks/workload_webhook.go b/pkg/webhooks/workload_webhook.go
index bff012c46a..4b6e04551e 100644
--- a/pkg/webhooks/workload_webhook.go
+++ b/pkg/webhooks/workload_webhook.go
@@ -105,8 +105,17 @@ func ValidateWorkload(obj *kueue.Workload) field.ErrorList {
 	var allErrs field.ErrorList
 	specPath := field.NewPath("spec")
 
+	variableCountPosets := 0
 	for i := range obj.Spec.PodSets {
-		allErrs = append(allErrs, validatePodSet(&obj.Spec.PodSets[i], specPath.Child("podSets").Index(i))...)
+		ps := &obj.Spec.PodSets[i]
+		allErrs = append(allErrs, validatePodSet(ps, specPath.Child("podSets").Index(i))...)
+		if ps.MinCount != nil {
+			variableCountPosets++
+		}
+	}
+
+	if variableCountPosets > 1 {
+		allErrs = append(allErrs, field.Invalid(specPath.Child("podSets"), variableCountPosets, "at most one podSet can use minCount"))
 	}
 
 	if len(obj.Spec.PriorityClassName) > 0 {
diff --git a/pkg/webhooks/workload_webhook_test.go b/pkg/webhooks/workload_webhook_test.go
index 5c69f4b94e..6112ee8902 100644
--- a/pkg/webhooks/workload_webhook_test.go
+++ b/pkg/webhooks/workload_webhook_test.go
@@ -266,6 +266,17 @@ func TestValidateWorkload(t *testing.T) {
 				field.Forbidden(podSetsPath.Index(0).Child("minCount"), ""),
 			},
 		},
+		"too many variable count podSets": {
+			workload: testingutil.MakeWorkload(testWorkloadName, testWorkloadNamespace).
+				PodSets(
+					*testingutil.MakePodSet("ps1", 3).SetMinimumCount(2).Obj(),
+					*testingutil.MakePodSet("ps2", 3).SetMinimumCount(1).Obj(),
+				).
+				Obj(),
+			wantErr: field.ErrorList{
+				field.Invalid(podSetsPath, nil, ""),
+			},
+		},
 	}
 	for name, tc := range testCases {
 		t.Run(name, func(t *testing.T) {