ldc-legaulois/app/Http/Requests/SearchCustomerCollectionRequest.php

<?php

namespace App\Http\Requests;

class SearchCustomerCollectionRequest extends CustomerCollectionRequest
{
    /**
     * Get the validation rules that apply to the request.
     *
     * @return array
     */
    public function rules()
    {
        return array_merge(
            parent::rules(),
            [
                'pseudo' => 'sometimes|string',
                'departaimant' => 'sometimes|string'
            ]
        );
    }
}