feat: add validation support in marker type

pkg/simpleschema/markers.go

@@ -50,12 +50,14 @@ const (
 	MarkerTypeMinimum MarkerType = "minimum"
 	// MarkerTypeMaximum represents the `maximum` marker.
 	MarkerTypeMaximum MarkerType = "maximum"
+	// MarkerTypeValidation represents the `validation` marker.
+	MarkerTypeValidation MarkerType = "validation"
 )
 
 func markerTypeFromString(s string) (MarkerType, error) {
 	switch MarkerType(s) {
 	case MarkerTypeRequired, MarkerTypeDefault, MarkerTypeDescription,
-		MarkerTypeMinimum, MarkerTypeMaximum:
+		MarkerTypeMinimum, MarkerTypeMaximum, MarkerTypeValidation:
 		return MarkerType(s), nil
 	default:
 		return "", fmt.Errorf("unknown marker type: %s", s)

pkg/simpleschema/markers_test.go

@@ -124,6 +124,15 @@ func TestParseMarkers(t *testing.T) {
 			},
 			wantErr: false,
 		},
+		{
+			name:  "validation marker with one value",
+			input: "validation=\"oldself=self\" required=true",
+			want: []*Marker{
+				{MarkerType: MarkerTypeValidation, Key: "validation", Value: "oldself=self"},
+				{MarkerType: MarkerTypeRequired, Key: "required", Value: "true"},
+			},
+			wantErr: false,
+		},
 	}
 
 	for _, tt := range tests {

pkg/simpleschema/transform.go

@@ -212,6 +212,13 @@ func (tf *transformer) applyMarkers(schema *extv1.JSONSchemaProps, markers []*Ma
 			if val, err := strconv.ParseFloat(marker.Value, 64); err == nil {
 				schema.Maximum = &val
 			}
+		case MarkerTypeValidation:
+			newRule := extv1.ValidationRule{
+				Rule: marker.Value,
+			}
+			if parentSchema != nil {
+				parentSchema.XValidations = append(parentSchema.XValidations, newRule)
+			}
 		}
 	}
 }