这段laravel代码的走向是怎么走的流程？

//Controller：
$userBonus = UserBonusModel::with(['event' => function ($query) {
            $query->with(['capitals' => function ($query) {
                $query->select(['id', 'user_id', 'balance']);
            }]);
        }])->latest()->paginate();

//Model：
protected static function boot()
    {
        parent::boot();
        static::addGlobalScope(new IsOnScope());
    }

    public function event()
    {
        return $this->morphTo();
    }