Add CEL tests for snippetsFilter API (#3750)

Problem: As code owners we want to verify is API validation is working as expected for SnippetsFilter

Solution: Added CEL tests for SnippetsFilter

Author: salonichf5

tests/cel/common.go

@@ -61,6 +61,11 @@ const (
 	expectedTargetRefNameUniqueError  = `TargetRef Name must be unique`
 )
 
+// SnippetsFilter validation errors.
+const (
+	expectedSnippetsFilterContextError = `Only one snippet allowed per context`
+)
+
 const (
 	defaultNamespace = "default"
 )

tests/cel/snippetsfilter_test.go

@@ -0,0 +1,77 @@
+package cel
+
+import (
+	"testing"
+
+	controllerruntime "sigs.k8s.io/controller-runtime"
+
+	ngfAPIv1alpha1 "github.com/nginx/nginx-gateway-fabric/v2/apis/v1alpha1"
+)
+
+func TestSnippetsFilterValidation(t *testing.T) {
+	t.Parallel()
+	k8sClient := getKubernetesClient(t)
+
+	tests := []struct {
+		name       string
+		wantErrors []string
+		spec       ngfAPIv1alpha1.SnippetsFilterSpec
+	}{
+		{
+			name: "Validate single snippet with valid context",
+			spec: ngfAPIv1alpha1.SnippetsFilterSpec{
+				Snippets: []ngfAPIv1alpha1.Snippet{
+					{
+						Context: ngfAPIv1alpha1.NginxContextHTTP,
+						Value:   "limit_req zone=one burst=5 nodelay;",
+					},
+				},
+			},
+		},
+		{
+			name: "Validate multiple snippets with unique contexts",
+			spec: ngfAPIv1alpha1.SnippetsFilterSpec{
+				Snippets: []ngfAPIv1alpha1.Snippet{
+					{
+						Context: ngfAPIv1alpha1.NginxContextMain,
+						Value:   "worker_processes 4;",
+					},
+					{
+						Context: ngfAPIv1alpha1.NginxContextHTTPServer,
+						Value:   "server_name example.com;",
+					},
+				},
+			},
+		},
+		{
+			name:       "Validate duplicate contexts are not allowed",
+			wantErrors: []string{expectedSnippetsFilterContextError},
+			spec: ngfAPIv1alpha1.SnippetsFilterSpec{
+				Snippets: []ngfAPIv1alpha1.Snippet{
+					{
+						Context: ngfAPIv1alpha1.NginxContextHTTP,
+						Value:   "limit_req zone=one burst=5 nodelay;",
+					},
+					{
+						Context: ngfAPIv1alpha1.NginxContextHTTP,
+						Value:   "sendfile on;",
+					},
+				},
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			t.Parallel()
+			snippetsFilter := &ngfAPIv1alpha1.SnippetsFilter{
+				ObjectMeta: controllerruntime.ObjectMeta{
+					Name:      uniqueResourceName(testResourceName),
+					Namespace: defaultNamespace,
+				},
+				Spec: tt.spec,
+			}
+			validateCrd(t, tt.wantErrors, snippetsFilter, k8sClient)
+		})
+	}
+}