symfony2 embedded form collection and entity mapping - php

Question

I was following the symfony2 tutorial on how to create an embedded form collection but wasn't able to implement it since it only creates a junction table.
According to doctrine2 documentation:
"Why are many-to-many associations less common? Because frequently you want to associate additional attributes with an association, in which case you introduce an association class. Consequently, the direct many-to-many association disappears and is replaced by one-to-many/many-to-one associations between the 3 participating classes."
Here are some snippets of my code:
src/AppBundle/Entity/Ingredient.php
/**
* Defines the properties of the Ingredient entity to represent the portal ingredients.
*
* #author furious_snail
*
* #ORM\Entity()
* #ORM\Table(name="ingredients")
* #UniqueEntity("name")
*/
class Ingredient
{
/**
* #ORM\Id()
* #ORM\Column(type="integer")
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #ORM\ManyToOne(targetEntity="IngredientCategory")
* #ORM\JoinColumn(name="category_id", referencedColumnName="id", nullable=true)
*/
private $category;
/**
* #ORM\Column(type="string", unique=true)
*/
private $name;
/**
* #ORM\OneToMany(targetEntity="IngredientNutrient", mappedBy="ingredient", cascade={"persist", "remove"})
*/
private $nutrientsPer100G;
public function __construct()
{
$this->substitute = new ArrayCollection();
$this->nutrientsPer100G = new ArrayCollection();
}
public function getId()
{
return $this->id;
}
public function setName($name)
{
$this->name = $name;
}
public function getName()
{
return $this->name;
}
/**
* #param mixed $nutrientsPer100G
*/
public function setNutrientsPer100G($nutrientsPer100G)
{
$this->nutrientsPer100G = $nutrientsPer100G;
}
/**
* #return array
*/
public function getNutrientsPer100G()
{
return $this->nutrientsPer100G;
}
}
src/AppBundle/Entity/IngredientNutrient.php
/**
* #ORM\Entity()
* #ORM\Table(name="ingredient_nutrient")
*/
class IngredientNutrient
{
/**
* #ORM\Id()
* #ORM\Column(type="integer")
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #var integer
*
* #ORM\ManyToOne(targetEntity="Ingredient", inversedBy="nutrientsPer100G")
* #ORM\JoinColumn(name="ingredient_id", referencedColumnName="id", nullable=true)
*/
protected $ingredient;
/**
* #var integer
*
* #ORM\ManyToOne(targetEntity="Nutrient")
* #ORM\JoinColumn(name="nutrient_id", referencedColumnName="id", nullable=true)
*/
protected $nutrient;
/**
* #ORM\Column(type="float")
*/
private $quantity;
/**
* #ORM\ManyToOne(targetEntity="Unit")
* #ORM\JoinColumn(name="unit_id", referencedColumnName="id", nullable=true)
*/
private $unit;
/**
* #return mixed
*/
public function getId()
{
return $this->id;
}
/**
* #return mixed
*/
public function getIngredient()
{
return $this->ingredient;
}
/**
* #param mixed $ingredient
*/
public function setIngredient($ingredient)
{
$this->ingredient = $ingredient;
}
/**
* #return mixed
*/
public function getNutrient()
{
return $this->nutrient;
}
/**
* #param mixed $nutrient
*/
public function setNutrient($nutrient)
{
$this->nutrient = $nutrient;
}
/**
* #return mixed
*/
public function getQuantity()
{
return $this->quantity;
}
/**
* #param mixed $quantity
*/
public function setQuantity($quantity)
{
$this->quantity = $quantity;
}
/**
* #return mixed
*/
public function getUnit()
{
return $this->unit;
}
/**
* #param mixed $unit
*/
public function setUnit($unit)
{
$this->unit = $unit;
}
}
src/AppBundle/Form/Type/IngredientNutrientType.php
class IngredientNutrientType extends AbstractType
{
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('nutrient', 'entity', array(
'class' => 'AppBundle\Entity\Nutrient',
'choice_label' => 'name',
'label' => 'Nutrient',
))
->add('quantity', null, array('label' => 'Cantitate'))
->add('unit', 'entity', array(
'class' => 'AppBundle\Entity\Unit',
'choice_label' => 'unit',
'label' => 'Unitate de masura'
));
}
public function configureOptions(OptionsResolver $resolver)
{
$resolver->setDefaults(array(
'data_class' => 'AppBundle\Entity\IngredientNutrient',
));
}
public function getName()
{
return 'app_ingredient_nutrient';
}
}
src/AppBundle/Form/Type/IngredientType.php
class IngredientType extends AbstractType
{
public function buildForm(FormBuilderInterface $builder, array $options)
{
$builder
->add('name', null, array('label' => 'Name'))
->add('nutrients_per_100_g', 'collection', array(
'type' => new IngredientNutrientType(),
'allow_add' => true,
'label' => 'Nutrient quantity per 100g',
'options' => array('label' => false),
));
}
public function configureOptions(OptionsResolver $resolver)
{
$resolver->setDefaults(array(
'data_class' => 'AppBundle\Entity\Ingredient',
));
}
public function getName()
{
return 'app_ingredient';
}
}
This works, I do get an embedded form collection but the issue is that the ingredient_id in the ingredient_nutrient table is null. How do I make it to fill the table with the right ID?
These are the fields I get on the page:
Name:
Nutrient:
Quantity:
Unit:
The idea is that if I have IngredientNutrient form tied with Ingredient form the user shouldn't have to specify ingredient name twice.
Thank you.

Answer 1

To start with, you need to "cross reference" your entities:
public function setNutrientsPer100G($nutrientsPer100G)
{
$this->nutrientsPer100G = $nutrientsPer100G;
$nutrientsPer100G->setIngrediant($this);
}
Make sure both sides of the relation are being set. That will take care of the null id issues.
The other problem is that you are using collections in your Ingrediant/Nutrient entities but your set methods are not using the array operators.