App\Ninja\Datatables\ProductDatatable::columns PHP Method

    public function columns()
    {
        return [['product_key', function ($model) {
            return link_to('products/' . $model->public_id . '/edit', $model->product_key)->toHtml();
        }], ['notes', function ($model) {
            return nl2br(Str::limit($model->notes, 100));
        }], ['cost', function ($model) {
            return Utils::formatMoney($model->cost);
        }], ['tax_rate', function ($model) {
            return $model->tax_rate ? $model->tax_name . ' ' . $model->tax_rate . '%' : '';
        }, Auth::user()->account->invoice_item_taxes]];
    }