how to declare global variable in laravel controller

SET configuration variables at runtime:
class AppServiceProvider extends ServiceProvider
{
    public function boot()
    {
        View::share('key', 'value');
        Schema::defaultStringLength(191);
        $company=DB::table('company')->where('id',1)->first();
        config(['yourconfig.company' => $company]);
    }
}

USE:
config('yourconfig.company');

class TestController extends Controller
{
    private $x;

    public function index()
    {
        $this->x ='22';
    }

    public function send_message()
    {
        echo $this->x;
    }
}

 //Into the console
 php artisan clear-compiled
 php artisan config:cache

Composer //Autload whitin composer.json method
|
|--->Laravel App //My method
     |
     |--->Controller //Trait method
     |--->Blade //Trait method
     |--->Listener //Trait method
     |--->...

 //Into the console
 php artisan make:provider GlobalFunctionsServiceProvider