Example of Laravel Request to rules by locales

CustomPageRequest.php

<?php

namespace App\Http\Requests;

use App\CustomPage;
use App\Http\Requests\Request;
use Illuminate\Support\Facades\Config;

class CustomPageRequest extends Request
{
    /**
     * Determine if the user is authorized to make this request.
     *
     * @return bool
     */
    public function authorize()
    {
        return true;
    }

    /**
     * Get the validation rules that apply to the request.
     *
     * @return array
     */
    public function rules()
    {
        $available_locales = Config::get('translatable.locales');
        $fallback_locale = Config::get('translatable.fallback_locale');
        $rules = [];

        foreach($available_locales as $available_locale){
            if($fallback_locale == $available_locale){
                $rules[$available_locale.'.menu_name']  = 'required|max:50';
                $rules[$available_locale.'.title']      = 'required|max:150';
                $rules[$available_locale.'.content']    = 'required';
            } else {
                $rules[$available_locale.'.menu_name']  = 'max:50';
                $rules[$available_locale.'.title']      = 'max:150';
                $rules[$available_locale.'.content']    = '';
            }
        }

        return $rules;
    }
}