Database\Table: Simple mapping

OndrejSlamecka

Every row Database\Table outputs is an ActiveRow created in Selection::createRow. Overloading createRow is complicated because that would require extending class Selection and it is hardcoded into SelectionFactory which is hardcoded into Nette extension of DI container builder.

I therefore propose that Nette would allow the following configuration:

database:
    mapping: App\Entity\*

This mapping property would be injected into Selection. In createRow the * would be replaced with table name, it would be verified that class_exist and finally a new instance (object) of that class would be created and returned. If mapping was unset/null or class_exist would fail then it would fallback to ActiveRow (⇒ no BC break!).

Let me know what do you think.

(You may ask: Why use custom entities? Imagine object Product with properties Price and Vat. You want to get price with VAT at 20 places in the template. Simple Product::getPriceWithVat() would make it simple and prevent code repeating.)

Last edited by OndrejSlamecka (2013-08-30 19:17)

jiri.pudil

I believe composition is a much better approach here, as NDb is not an ORM. Something like:

class Product extends Nette\Object
{

	private $row;


	public function __construct(ActiveRow $row)
	{
		$this->row = $row;
	}


	public function getPriceWithVat()
	{
		// e.g.
		return $this->row->price * (1 + $this->row->vat);
	}

}

OndrejSlamecka

With the code you showed you would have to create an instance of that class on every result from Database\Table.

OndrejSlamecka

Proof of concept (mapping is simpler than described above just <tableName>: <className> array): https://github.com/…210d714dabe0 (entity class should be required to extend ActiveRow)

EDIT: A better implementation occured to me, which does not implement mapper but adds RowFactory (a service which anyone can replace with their own). PoC here: https://github.com/…4fb5f69220a8

Last edited by OndrejSlamecka (2014-09-20 10:42)