QueryParamVerifierV3 resilient to minimal OpenAPI V3 documents

staging/src/k8s.io/cli-runtime/pkg/resource/query_param_verifier_v3.go

@@ -106,6 +106,9 @@ func hasGVKExtensionV3(extensions spec.Extensions, gvk schema.GroupVersionKind)
 // the PATCH end-point. Returns true if the query param is supported by the
 // spec for the passed GVK; false otherwise.
 func supportsQueryParamV3(doc *spec3.OpenAPI, gvk schema.GroupVersionKind, queryParam VerifiableQueryParam) bool {
+	if doc == nil || doc.Paths == nil {
+		return false
+	}
 	for _, path := range doc.Paths.Paths {
 		// If operation is not PATCH, then continue.
 		op := path.PathProps.Patch

staging/src/k8s.io/cli-runtime/pkg/resource/query_param_verifier_v3_test.go

@@ -23,6 +23,7 @@ import (
 	"k8s.io/client-go/openapi/cached"
 	"k8s.io/client-go/openapi/openapitest"
 	"k8s.io/client-go/openapi3"
+	"k8s.io/kube-openapi/pkg/spec3"
 )
 
 func TestV3SupportsQueryParamBatchV1(t *testing.T) {
@@ -135,3 +136,70 @@ func TestV3SupportsQueryParamBatchV1(t *testing.T) {
 		})
 	}
 }
+
+func TestInvalidOpenAPIV3Document(t *testing.T) {
+	tests := map[string]struct {
+		spec *spec3.OpenAPI
+	}{
+		"nil document correctly returns Unsupported error": {
+			spec: nil,
+		},
+		"empty document correctly returns Unsupported error": {
+			spec: &spec3.OpenAPI{},
+		},
+		"minimal document correctly returns Unsupported error": {
+			spec: &spec3.OpenAPI{
+				Version: "openapi 3.0.0",
+				Paths:   nil,
+			},
+		},
+		"document with empty Paths correctly returns Unsupported error": {
+			spec: &spec3.OpenAPI{
+				Version: "openapi 3.0.0",
+				Paths:   &spec3.Paths{},
+			},
+		},
+	}
+
+	gvk := schema.GroupVersionKind{
+		Group:   "batch",
+		Version: "v1",
+		Kind:    "Job",
+	}
+	for tn, tc := range tests {
+		t.Run(tn, func(t *testing.T) {
+
+			verifier := &queryParamVerifierV3{
+				finder: NewCRDFinder(func() ([]schema.GroupKind, error) {
+					return []schema.GroupKind{}, nil
+				}),
+				root:       &fakeRoot{tc.spec},
+				queryParam: QueryParamFieldValidation,
+			}
+			err := verifier.HasSupport(gvk)
+			if err == nil {
+				t.Errorf("Expected not supports error, but none received.")
+			}
+		})
+	}
+}
+
+// fakeRoot implements Root interface; manually specifies the returned OpenAPI V3 document.
+type fakeRoot struct {
+	spec *spec3.OpenAPI
+}
+
+func (f *fakeRoot) GroupVersions() ([]schema.GroupVersion, error) {
+	// Unused
+	return nil, nil
+}
+
+// GVSpec returns hard-coded OpenAPI V3 document.
+func (f *fakeRoot) GVSpec(gv schema.GroupVersion) (*spec3.OpenAPI, error) {
+	return f.spec, nil
+}
+
+func (f *fakeRoot) GVSpecAsMap(gv schema.GroupVersion) (map[string]interface{}, error) {
+	// Unused
+	return nil, nil
+}