Validation for prices and objection

src/common/validators/money-amount-string.validator.ts

@@ -0,0 +1,37 @@
+import {
+  registerDecorator,
+  ValidationArguments,
+  ValidationOptions,
+  ValidatorConstraint,
+  ValidatorConstraintInterface,
+} from "class-validator";
+import { normalizeMoneyAmountString } from "src/utils/unicode-digits";
+
+@ValidatorConstraint({ name: "isMoneyAmountString", async: false })
+export class IsMoneyAmountStringConstraint
+  implements ValidatorConstraintInterface
+{
+  validate(value: unknown): boolean {
+    if (value == null || value === "") return true;
+    if (typeof value !== "string") return false;
+    const n = normalizeMoneyAmountString(value);
+    if (!n) return false;
+    return /^\d+(\.\d+)?$/.test(n);
+  }
+
+  defaultMessage(): string {
+    return "Must be a non-negative amount (digits only, optional decimal).";
+  }
+}
+
+export function IsMoneyAmountString(validationOptions?: ValidationOptions) {
+  return (object: object, propertyName: string) => {
+    registerDecorator({
+      target: object.constructor,
+      propertyName,
+      options: validationOptions,
+      constraints: [],
+      validator: IsMoneyAmountStringConstraint,
+    });
+  };
+}