500: Internal Server Error undefined index Symfony3 - json

Question

I'm trying to send from api rest controller (Symfony3) a object collection but get an error. "{"error":{"code":500,"message":"Internal Server Error","exception":[{"message":"Notice: Undefined index: Bar"
/**
*
*
* #Get("/api/bars.{_format}", defaults={"_format"="json"}, options={"expose"=true}, name="api_bars")
* #View()
*/
public function getBarsAction (Request $request)
{
$em = $this->getDoctrine()->getManager();
$session = $this->get('Session');
$repository = $em->getRepository('AppBundle:Bar');
$bars = $repository->findAll();
foreach ($bars as $bar)
{
$id = $bar->getId();
$name = $bar->getName();
$bars[] = array('id'=>$id,'name'=>$name);
}
$view = $this->View($bars,200);
return $this->handleView($view);
}
And the Bar Entity is:
<?php
namespace AppBundle\Entity;
use Doctrine\Common\Collections\ArrayCollection;
use Doctrine\ORM\Mapping as ORM;
/**
* Bar
*
* #ORM\Table(name="Bar")
* #ORM\Entity(repositoryClass="AppBundle\Repository\BarRepository")
*/
class Bar
{
/**
* #var int
*
* #ORM\Column(name="id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #var string
*
* #ORM\Column(name="name", type="string", length=45, nullable=true)
*/
private $name;
/**
* #var string
*
* #ORM\Column(name="location", type="string", length=45, nullable=true)
*/
private $location;
/**
* #var string
*
* #ORM\Column(name="description", type="string", length=45, nullable=true)
*/
private $description;
/**
* #ORM\OneToMany(targetEntity="Waiter", mappedBy="Bar")
*/
protected $waiters;
/**
* #ORM\OneToMany(targetEntity="Table_", mappedBy="Bar")
*/
protected $tables;
/** #ORM\OneToMany(targetEntity="Stock_food", mappedBy="Bar") */
private $stockfoods;
/** #ORM\OneToMany(targetEntity="Stock_drink", mappedBy="Bar") */
private $stockdrinks;
public function __construct()
{
$this->waiters = new ArrayCollection();
$this->tables = new ArrayCollection();
$this->stockfoods = new ArrayCollection();
$this->stockdrinks = new ArrayCollection();
}
/**
* Get id
*
* #return int
*/
public function getId()
{
return $this->id;
}
/**
* Set name
*
* #param string $name
*
* #return Bar
*/
public function setName($name)
{
$this->name = $name;
return $this;
}
/**
* Get name
*
* #return string
*/
public function getName()
{
return $this->name;
}
/**
* Set location
*
* #param string $location
*
* #return Bar
*/
public function setLocation($location)
{
$this->location = $location;
return $this;
}
/**
* Get location
*
* #return string
*/
public function getLocation()
{
return $this->location;
}
/**
* Set description
*
* #param string $description
*
* #return Bar
*/
public function setDescription($description)
{
$this->description = $description;
return $this;
}
/**
* Get description
*
* #return string
*/
public function getDescription()
{
return $this->description;
}
public function addWaiter($value){
$this->waiters[] = $value;
}
public function getWaiters(){
return $this->waiters;
}
public function removeWaiters($id)
{
//optionally add a check here to see that $group exists before removing it.
return $this->waiters->removeElement($id);
}
public function addTable($value){
$this->tables[] = $value;
}
public function getTables(){
return $this->tables;
}
public function removeTables($id)
{
//optionally add a check here to see that $group exists before removing it.
return $this->tables->removeElement($id);
}
public function addFood($value){
$this->stockfoods[] = $value;
}
public function getFoods(){
return $this->stockfoods;
}
public function removeFoods($id)
{
//optionally add a check here to see that $group exists before removing it.
return $this->stockfoods->removeElement($id);
}
public function addDrink($value){
$this->stockdrinks[] = $value;
}
public function getDrinks(){
return $this->stockdrinks;
}
public function removeDrinks($id)
{
//optionally add a check here to see that $group exists before removing it.
return $this->stockdrinks->removeElement($id);
}
}
Thanks a lot!!!!

Answer 1

I solved my problem!!! I was related to association mapping. I've changed this:
/**
* #ORM\OneToMany(targetEntity="Waiter", mappedBy="Bar")
*/
protected $waiters;
/**
* #ORM\OneToMany(targetEntity="Table_", mappedBy="Bar")
*/
protected $tables;
/** #ORM\OneToMany(targetEntity="Stock_food", mappedBy="Bar") */
private $stockfoods;
/** #ORM\OneToMany(targetEntity="Stock_drink", mappedBy="Bar") */
private $stockdrinks;
For this:
/**
* #ORM\OneToMany(targetEntity="Waiter", mappedBy="bar")
*/
protected $waiters;
/**
* #ORM\OneToMany(targetEntity="Table_", mappedBy="bar")
*/
protected $tables;
/** #ORM\OneToMany(targetEntity="Stock_food", mappedBy="bar") */
private $stockfoods;
/** #ORM\OneToMany(targetEntity="Stock_drink", mappedBy="bar") */
private $stockdrinks;