ldc-supportweb/app/Http/Requests/CreateMessage.php

<?php

namespace App\Http\Requests;

use Illuminate\Foundation\Http\FormRequest;

class CreateMessage extends FormRequest
{
    /**
     * Determine if the user is authorized to make this request.
     *
     * @return boolean
     */
    public function authorize()
    {
        /** @var \App\Models\User|null */
        if (!($user = auth()->user())) {
            return false;
        }
        return auth()->check() and auth()->user()->sites and (
            $user->isAdmin() or
            auth()->user()->sites->contains(request()->route()->ticket->site_id)
        );
    }

    /**
     * Prepare the data for validation.


     *
     * @return void
     */
    protected function prepareForValidation()
    {
        $this->merge([
            'subscribe' => $this->subscribe ? true : false
        ]);
    }

    /**
     * Get the validation rules that apply to the request.
     *
     * @return array
     */
    public function rules()
    {
        /** @var \App\Models\User */
        $user = auth()->user();
        return [
            'subscribe' => 'required|boolean',
            'message' => 'required|min:' . ($user->isAdmin() ? '5' : '20'),
            'file_message' => 'sometimes|mimes:jpeg,jpg,png,pdf|max:2048'
        ];
    }
}