Node Js: Validate empty array using class validator

Question

How to check whether the array is empty or not using class-validator.
Given below is my structure. I want to check if cartId is empty or not.

{
   "cartId": []
}

Answer 1

What you want is @ArrayNotEmpty(). You can find all built-in validators here: https://github.com/typestack/class-validator#validation-decorators

If you don't find - you can write your own validator: https://github.com/typestack/class-validator#custom-validation-classes

Answer 2

To check if array is empty, you can use @ArrayNotEmpty(), like this:

@ArrayNotEmpty({ each: true })
cartId: [];