Symfony2 Form Dynamic Choice Field With EAV Returned Values

Question

I am creating an E-Commerce Bundle with Symfony2 and Doctrine2. I am applying EAV approach for the product features and product values for unlimited features. For this, I have three basic entities: Product, FeatureKind and FeatureValues.

• FeatureKind is connected with FeatureValues with a OneToMany unidirectional relationship.
• Product is connected to FeatureKind with a ManyToMany relationship.

The Problem is the I need the FeatureType as labels and it's various values as a choice field in the product form. I have managed to get the featurekind and associated values in the product form but I don't know how to turn them into choice fields.

Following are all three Entities, Controller and Form Code and the result of my code.

Note: I have removed the extra things from code to keep it short.

Product.php

namespace Webmuch\ProductBundle\Entity;

/**
 * @ORM\Table()
 * @ORM\Entity
 */
class Product
{
    /**
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    private $id;

    /**
     * @ORM\Column(name="title", type="string", length=255)
     */
    private $title;

    /**
     * @ORM\ManyToMany(targetEntity="FeatureKind", inversedBy="product", cascade={"persist"})
     * @ORM\JoinTable(name="product_featurekind")
     **/
    private $featurekind;
}

FeatureKind.php

namespace Webmuch\ProductBundle\Entity;

/**
 * @ORM\Table(name="feature_kind")
 * @ORM\Entity
 */
class FeatureKind
{
    /**
     * @ORM\Id
     * @ORM\Column(name="id", type="integer")
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    protected $id;

    /**
     * @ORM\Column(name="name", type="string", length=50)
     */
    protected $name;

    /**
     * @ORM\ManyToMany(targetEntity="FeatureValue")
     * @ORM\JoinTable(name="feature_kind_value",
     *      joinColumns={@ORM\JoinColumn(name="kind_id", referencedColumnName="id")},
     *      inverseJoinColumns={@ORM\JoinColumn(name="value_id", referencedColumnName="id", unique=true)}
     *      )
     **/
    protected $values;   
}

FeatureValue.php

namespace Webmuch\ProductBundle\Entity;

/**
 * @ORM\Table()
 * @ORM\Entity
 */
class FeatureValue
{
    /**
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    protected $id;

    /**
     * @ORM\Column(name="value", type="string", length=100)
     */
    protected $value;
}

ProductController.php

public function newAction(Request $request)
{
    $entity = new Product();
    $em = $this->getDoctrine()->getEntityManager();
    $features = $em->getRepository('ProductBundle:FeatureKind')->findAll();

    foreach($features as $feature)
    {
        $featurekind = new FeatureKind();
        $featurekind->setTitle($feature->getTitle());
        foreach($feature->getValue() as $value ){
            $featurekind->getValue()->add($value);
        }
        $entity->getFeaturekind()->add($featurekind);   
    }

    $form = $this->createForm(new ProductType(), $entity);

     if ('POST' === $request->getMethod()) {
        $form->bindRequest($request);
        if ($form->isValid()) {
            $em->persist($entity);
            $em->flush();

            return $this->redirect($this->generateUrl('product_show', array(
                'id' => $entity->getId()
            )));
        }
    }
    return $this->render('ProductBundle:Product:new.html.twig', array(
       'form'   => $form->createView()
    ));
}

ProductType.php

namespace Webmuch\ProductBundle\Form;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilder;

class ProductType extends AbstractType
{
    public function buildForm(FormBuilder $builder, array $options)
    {
        $builder
            ->add('featurekind', 'collection', array('type' => new FeatureKindType()))
            ->getForm();
        }

    public function getDefaultOptions(array $options)
    {
        return array(
            'data_class' => 'Webmuch\ProductBundle\Entity\Product',
            'required' => true
        );
    }

    public function getName()
    {
        return 'product';
    }
}

FeatureKindType.php

namespace Webmuch\ProductBundle\Form;

class FeatureKindType extends AbstractType
{
    public function buildForm(FormBuilder $builder, array $options)
    {
        $builder
            ->add('title')
            ->add('value','collection', array(
                                               'type' => new FeatureValueType(),
                                               'allow_add'=>true))
            ->getForm();
    }

    public function getDefaultOptions(array $options)
    {
        return array(
            'data_class' => 'Webmuch\ProductBundle\Entity\FeatureKind',
        );
    }

    public function getName()
    {
        return 'featurekind';
    }
}

EDIT:

I after a few days of work, I am now stuck with a simple array of features and their respective multiple values:

Array
(
    [Color] => Array
        (
            [Red] => Red
            [Green] => Green
        )

    [Size] => Array
        (
            [Large] => Large
            [Medium] => Medium
            [Small] => Small
        )

    [Sleeve Style] => Array
        (
            [Half Sleeved] => Half Sleeved
            [Full Sleeved] => Full Sleeved
            [Cut Sleeves] => Cut Sleeves
        )

)

I have tried to create the form as follows: $this->choices contains the array.

$builder
    ->add('name')
    ->add('slug')
    ->add('active')
;

foreach ($this->choices as $choice) {
    $builder->add('featurekind', 'choice', array(
        'required' => 'false',
        'choices' => $choice,
        'empty_value' => 'Choose an option',
        'empty_data'  => null
    ));
}

$builder->getForm();

The above doesn't work on the property $featurekind. I get the error:

Notice: Object of class Doctrine\Common\Collections\ArrayCollection could not be converted to int in /vagrant/project/vendor/symfony/symfony/src/Symfony/Component/Form/Extension/Core/ChoiceList/ChoiceList.php line 457

Although if the form field is attached to any un-associated property, for example: $name, it still creates only one form field for the last iteration of the loop.

I am out of options.

Answer 1

What you want to do cannot be done with your current structure. Let me try to explain: FeatureKind has a one to many relationship with FeatureValue. This means that you can have a "color" kind which can have values "red","pink" etc.. This is fine. But your product entity has a collection of FeatureKind objects, so it can have a list like "Color", "Size", etc... BUT (this is the most important part) it has no way of asiginig a specific Value to any of these Kinds: there is no property which holds the specific value for each kind. I hope you could undestand this, it is a bit difficult to explain.

What you need to do:

Define your FeatureValue and FeatureKind classes just as they are.

Define a NEW entity which handles an association between a kind and a value for a product:

namespace Webmuch\ProductBundle\Entity;

/**
 * @ORM\Table()
 * @ORM\Entity
 */
class FeatureKindValue
{
    /**
     * @ORM\Id
     * @ORM\Column(name="id", type="integer")
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    protected $id;

    /**
     * @ManyToOne(targetEntity="Product", inversedBy="features")
     **/
    private $product;

    /**
     * @ORM\ManyToOne(targetEntity="FeatureKind")
     **/
    protected $kind;   

    /**
     * @ORM\ManyToOne(targetEntity="FeatureValue")
     **/
    protected $value;   
}

This entity handles pairs of kind:value, for example color:red

Finally, your product entity has a property of this new type:

namespace Webmuch\ProductBundle\Entity;

/**
 * @ORM\Table()
 * @ORM\Entity
 */
class Product
{
    /**
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    private $id;

    /**
     * @ORM\Column(name="title", type="string", length=255)
     */
    private $title;

    /**
     * @ORM\OneToMany(targetEntity="FeatureKindValue", mappedBy="product")
     **/
    private $features;
}

Then, in order to present the form as you want, do something similar to the instructions given in the answer to this stackoverflow question

Answer 2

This kind of stuff can be tricky, but you can use this approach in your FeatureKindType class:

public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder->addEventListener(
        FormEvents::PRE_SET_DATA,
        function (DataEvent $event) use ($builder) {
            /* @var FormBuilderInterface $builder */
            $form = $event->getForm();
            /* @var FeatureKind $data */
            $data = $event->getData();
            if ($data !== null) {
                $form->add(
                    $builder->getFormFactory()->createNamed(
                        'values',
                        'entity',
                        null,
                        array(
                            'label' => $data->getName(),
                            'class' => 'WebmuchProductBundle:FeatureValue',
                        )
                    )
                );
            }
        }
    );
}

Mind you, I have not tried to post the form and save the entities in your case, but the form now diplays the name of the FeatureKind as label and a dropdown select containing the respective FeatureKindValues.

I use this approach in a project of mine, and it works for me.