How to Validate Array of Urls using Class-Validator?

Question

I am using Class-Validator to validate Properties of DTOs for Nest.js Application. In there I have a Property "images", which is an Array of Strings and those Strings are Urls. So, I want to validate each and every Url in that Array.

class SomeDto {
// ...
       
// Array of Urls
@IsArray()
@IsUrl({each:true})
images: string[];

// ...
}

But this doesn't seem to work. Does anyone know how to validate this Array of Urls.

Answer 1

The type of the first parameter of IsUrl is not the usual ValidationOptions one.

You can check its signature:

export declare function IsUrl(options?: ValidatorJS.IsURLOptions, validationOptions?: ValidationOptions): PropertyDecorator;

So, try to pass the { each: true } in the second place and it will work.

class SomeDto {
// ...
       
// Array of Urls
@IsArray()
@IsUrl({}, { each: true })
images: string[];

// ...
}