Symfony4: How to recieve data from linked entity? - symfony

Question

Orders // orders
Comments // comments for every order
I would like to find latest comment written in this order.
My
Controller:
$orders = $this->getDoctrine()->getRepository(Orders::class)->findAll();
foreach($orders as $order) {
$temp = array(
$order->getId(),
$order->getComments()->findLatest( $order->getId() )
Entity (Comments):
/**
* #ORM\ManyToOne(targetEntity="App\Entity\Orders", inversedBy="comments")
*/
private $orders;
Entity(Order):
/**
* #return Collection|Comment[]
*/
public function getComments(): Collection
{
return $this->comments;
}
Comment Repository:
public function findLatest($value)
{
return $this->createQueryBuilder('c')
->andWhere('c.orders = :val')
->setParameter('val', $value)
->orderBy('c.id', 'DESC')
->setMaxResults(1)
->getQuery()
->getResult()
;
}
But looks like it not working in this way :(
Error:
Attempted to call an undefined method
named "findLatest" of class "Doctrine\ORM\PersistentCollection".

Answer 1

you are trying to call a repository function from another entity
try to change this line :
$order->getComments()->findLatest( $order->getId()
with:
$this->getDoctrine()->getRepository(Comments::class)->findLatest($order->getId);
a better soulution will be that you work with $orders->getComments() array to avoid requesting data from the database inside a loop

Answer 2

You can do this using the class Doctrine\Common\Collections\Criteria.
Entity(Order):
use Doctrine\Common\Collections\Criteria;
...
/**
* Returns the latest comment or false if no comments found under that criteria
*/
public function findLatestComment()
{
$criteria = Criteria::create()
->orderBy(array("id" => Criteria::DESC))
;
return $this->getComments()->matching($criteria)->first();
}
And then you can simply use it like this:
$order->findLatestComment();