Illuminate\Routing\UrlGenerator::forceSchema PHP Method

    public function forceSchema($schema)
    {
        $this->cachedSchema = null;
        $this->forceSchema = $schema . '://';
    }

 /**
  * Bootstrap any application services.
  *
  * @return void
  */
 public function boot(UrlGenerator $url)
 {
     //
     if (env('APP_ENV') !== 'local') {
         $url->forceSchema('https');
     }
 }