numberRule

numberRule<TOptions>(options): NumberRule<TOptions>

Defined in: packages/ddd-core/domain/rules/number.rule.ts:95

Defines the rule for one number field of an aggregate: declared once, used by the aggregate to parse the value, and read by other layers (such as a request schema) for its limits.

parse(value) checks, in this order:

1. null or undefined: null, or a required violation;
2. not a number: a type violation (a numeric string is not converted);
3. NaN or an infinity: a finite violation;
4. with integer, not a safe integer: an integer violation;
5. min, then max.

Type Parameters

TOptions

TOptions extends NumberRuleOptions

Parameters

options

TOptions

The field name, its constraints and its error.

Returns

NumberRule<TOptions>

The frozen rule.

Throws

TypeError when an option is invalid: an empty field, a bound that is not a finite number, or min above max.

Example

export class Order extends RootEntity<OrderSnapshot> {
  static readonly rules = {
    quantity: numberRule({
      field: 'quantity',
      integer: true,
      min: 1,
      max: 100,
      error: (violation) => new InvalidQuantityException(violation),
    }),
  } as const;

  @Mutable<number>({ normalize: (value) => Order.rules.quantity.parse(value) })
  private _quantity: number;
}

Order.rules.quantity.parse(0);
// throws InvalidQuantityException: "quantity must be at least 1."