Adding complex data to existing entities

Adding complex data to existing entities
Overview
Sometimes you want to extend existing entities with some custom information, this guide will have you covered. Extensions are technical and not configurable by the admin user just like that. Also they can deal with more complex types than scalar ones.
Prerequisites
In order to create your own entity extension for your plugin, you first need a plugin as base. Therefore, you can refer to the Plugin Base Guide.
Also, basic knowledge of creating a custom entity and adding associations to it are very helpful here.
Creating the extension
In this example we're going to add a new string field to the product entity.
You can choose whether or not you want to save the new string field to the database or not. Therefore, you're going to see two sections, one for each way.
For both cases, you need to create a new "extension" class in the directory <plugin root>/src/Extension/. In this case we want to extend the product entity, so we create a subdirectory Content/Product/ since the entity is located there in the Core. Our class then has to extend from the abstract Shopware\Core\Framework\DataAbstractionLayer\EntityExtension class, which forces you to implement the getDefinition method. It has to point to the entity definition you want to extend, so ProductDefinition in this case.
Now you add new fields by overriding the method extendFields and add your new fields in there.
Here's an example class called CustomExtension:
<plugin root>/src/Extension/Content/Product/CustomExtension.php
<?php declare(strict_types=1);
​
namespace Swag\BasicExample\Extension\Content\Product;
​
use Shopware\Core\Content\Product\ProductDefinition;
use Shopware\Core\Framework\DataAbstractionLayer\EntityExtension;
use Shopware\Core\Framework\DataAbstractionLayer\FieldCollection;
​
class CustomExtension extends EntityExtension
{
    public function extendFields(FieldCollection $collection): void
    {
        $collection->add(
            // new fields here
        );
    }
​
    public function getDefinitionClass(): string
    {
        return ProductDefinition::class;
    }
}
Now we have to register our extension via the DI-container. If you don't know how that's done in general, head over to our guide about registering a custom service Add a custom class / service or our guide about the dependency injection.
Here's our services.xml:
<plugin root>/src/Resources/config/services.xml
<?xml version="1.0" ?>
​
<container xmlns="http://symfony.com/schema/dic/services"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
​
    <services>
        <service id="Swag\BasicExample\Extension\Content\Product\CustomExtension">
            <tag name="shopware.entity.extension"/>
        </service>
    </services>
</container>
Adding a field with database
In this guide you're extending the product entity in order to add a new string field to it. Since you must not extend the product table with a new column, you'll have to add a new table which contains the new data for the product. This new table will then be associated using a OneToOne association.
Let's start with the CustomExtension class by adding a new field in the extendFields method.
<plugin root>/src/Extension/Content/Product/CustomExtension.php
<?php declare(strict_types=1);
​
namespace Swag\BasicExample\Extension\Content\Product;
use Shopware\Core\Content\Product\ProductDefinition;
use Shopware\Core\Framework\DataAbstractionLayer\EntityExtension;
use Shopware\Core\Framework\DataAbstractionLayer\Field\OneToOneAssociationField;
use Shopware\Core\Framework\DataAbstractionLayer\FieldCollection;
​
class CustomExtension extends EntityExtension
{
    public function extendFields(FieldCollection $collection): void
    {
        $collection->add(
            new OneToOneAssociationField('exampleExtension', 'id', 'product_id', ExampleExtensionDefinition::class, true)
        );
    }
​
    public function getDefinitionClass(): string
    {
        return ProductDefinition::class;
    }
}
As you can see, we're adding a new OneToOneAssociationField. Its parameters are the following, in correct order:
propertyName: The name of the property which should contain the associated entity of type ExampleExtensionDefinition in the ProductDefinition.
storageName: Use the id column here, which refers to the id field of your product. This will be used for the connection to your association.
referenceField: In the storageName you defined one of the two connected columns, id. The name of the other column in the database, which you want to connect via this
association, belongs into this parameter. In that case, it will be a column called product_id, which we will define in the ExampleExtensionDefinition.
referenceClass: The class name of the definition that we want to connect via the association.
autoload: As the name suggests, this parameter defines if this association should always be loaded by default when the product is loaded. In this case, 
we definitely want that.
Creating ExampleExtensionDefinition
You most likely noticed the new classs ExampleExtensionDefinition, which we're going to create now. It will contain the actual string field that we wanted to add to the product.
Creating a new entity is not explained in this guide, so make sure you know this guide beforehand.
Our new entity will be located in the same directory as our extension. Let's first have a look at it before going into the explanation:
<plugin root>/src/Extension/Content/Product/ExampleExtensionDefinition.php
<?php declare(strict_types=1);
​
namespace Swag\BasicExample\Extension\Content\Product;
​
use Shopware\Core\Content\Product\ProductDefinition;
use Shopware\Core\Framework\DataAbstractionLayer\EntityDefinition;
use Shopware\Core\Framework\DataAbstractionLayer\Field\FkField;
use Shopware\Core\Framework\DataAbstractionLayer\Field\Flag\PrimaryKey;
use Shopware\Core\Framework\DataAbstractionLayer\Field\Flag\Required;
use Shopware\Core\Framework\DataAbstractionLayer\Field\IdField;
use Shopware\Core\Framework\DataAbstractionLayer\Field\OneToOneAssociationField;
use Shopware\Core\Framework\DataAbstractionLayer\Field\StringField;
use Shopware\Core\Framework\DataAbstractionLayer\FieldCollection;
​
class ExampleExtensionDefinition extends EntityDefinition
{
    public const ENTITY_NAME = 'swag_example_extension';
​
    public function getEntityName(): string
    {
        return self::ENTITY_NAME;
    }
​
    public function getEntityClass(): string
    {
        return ExampleExtensionEntity::class;
    }
​
    protected function defineFields(): FieldCollection
    {
        return new FieldCollection([
            (new IdField('id', 'id'))->addFlags(new Required(), new PrimaryKey()),
            new FkField('product_id', 'productId', ProductDefinition::class),
            (new StringField('custom_string', 'customString')),
​
            new OneToOneAssociationField('product', 'product_id', 'id', ProductDefinition::class, false)
        ]);
    }
}
We've created a new entity definition called ExampleExtensionDefinition, as mentioned in the CustomExtension class. Its database name will be swag_example_extension and it will have custom entity class called ExampleExtensionEntity, as you can see in the getEntityClass method. This will remain an example, creating the actual entity ExampleExtensionEntity is not part of this guide.
So let's have a look at the defineFields method. There's the default IdField, that almost every entity owns. The next field is the actual product_id column, which will be necessary in order to properly this entity with the product and vice versa. It has to be defined as FkField, since that's what it is: A foreign key.
Now we're getting to the actual new data, in this example this is just a new string field. It is called customString and could now be used in order to store new string data for the product in the database.
The last field is the inverse side of the OneToOneAssociationField. The first parameter defines the name of the propery again, which will contain the ProductEntity. Now have a look at the second and third parameter - those are the same as in the ProductDefinition, but the other way around. This is important, do not forget to do that!
The fourth parameter is the class of the associated definition, the ProductDefinition in this case. The last parameter, once again, defines the auto loading. In this example, the product definition will not be loaded, when you're just trying to load this extension entity. Yet, the extension entity will always automatically be loaded when the product entity is loaded, just like we defined earlier.
Of course, this new definition also needs to be registered to the DI container:
<plugin root>/src/Resources/config/services.xml
<?xml version="1.0" ?>
​
<container xmlns="http://symfony.com/schema/dic/services"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
​
    <services>
        <service id="Swag\BasicExample\Extension\Content\Product\CustomExtension">
            <tag name="shopware.entity.extension"/>
        </service>
​
        <service id="Swag\BasicExample\Extension\Content\Product\ExampleExtensionDefinition">
            <tag name="shopware.entity.definition" entity="swag_example_extension" />
        </service>
    </services>
</container>
Adding the new database table
Of course you have to add the new database table via a plugin migration. Have a look into the guide linked above to see how exactly this is done. Here's the example migration and how it could look like:
<?php declare(strict_types=1);
​
namespace Swag\BasicExample\Migration;
​
use Doctrine\DBAL\Connection;
use Shopware\Core\Framework\Migration\MigrationStep;
​
class Migration1614903457ExampleExtension extends MigrationStep
{
    public function getCreationTimestamp(): int
    {
        return 1614903457;
    }
​
    public function update(Connection $connection): void
    {
        $sql = <<<SQL
CREATE TABLE IF NOT EXISTS `swag_example_extension` (
    `id` BINARY(16) NOT NULL,
    `product_id` BINARY(16) NULL,
    `custom_string` VARCHAR(255) NULL,
    `created_at` DATETIME(3) NOT NULL,
    `updated_at` DATETIME(3) NULL,
    PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
SQL;
        $connection->executeStatement($sql);
    }
​
    public function updateDestructive(Connection $connection): void
    {
    }
}
Writing into the new field
As already mentioned, your new association is automatically being loaded every time a product entity is loaded. This section here will show you how to write to the new field instead.
As every write operation, this is done via the product repository in this example.
$this->productRepository->upsert([[
    'id' => '<your product ID here>',
    'exampleExtension' => [
        'customString' => 'foo bar'
    ]
]], $context);
In this case you'd write "foo bar" to the product with your desired ID. Note the keys exampleExtension, as defined in the product extension class CustomExtension, and the key customString, which is the property name that you defined in the ExampleExtensionDefinition class.
Adding a field without database
Adding a field without saving its value to the database is a lot less complicated. First of all, you'll have to let Shopware know that you're going to take care of this field yourself and it doesn't have to search for it in the database. This is done by using the Runtime flag on the new field.
<plugin root>/src/Extension/Content/Product/CustomExtension.php
<?php declare(strict_types=1);
​
namespace Swag\BasicExample\Extension\Content\Product;
​
use Shopware\Core\Content\Product\ProductDefinition;
use Shopware\Core\Framework\DataAbstractionLayer\EntityExtension;
use Shopware\Core\Framework\DataAbstractionLayer\Field\Flag\Runtime;
use Shopware\Core\Framework\DataAbstractionLayer\Field\StringField;
use Shopware\Core\Framework\DataAbstractionLayer\FieldCollection;
​
class CustomExtension extends EntityExtension
{
    public function extendFields(FieldCollection $collection): void
    {
        $collection->add(
            (new StringField('custom_string', 'customString'))->addFlags(new Runtime())
        );
    }
​
    public function getDefinitionClass(): string
    {
        return ProductDefinition::class;
    }
}
In this case, you directly add the StringField to the extension class itself. Afterwards we're adding the Runtime flag to this field, so Shopware knows that it doesn't have to take care of this new field automatically. We're doing this ourselves now.
For this we need a new subscriber. If you are not familiar with a subscriber, have a look at our Listening to events guide.
We can use the DAL event which gets fired every time the product entity is loaded. You can find those kind of events in the respective entities' event class, in this case it is Shopware\Core\Content\Product\ProductEvents.
Below you can find an example implementation where we add our extension, when the product gets loaded.
<plugin root>/src/Subscriber/ProductSubscriber.php
<?php declare(strict_types=1);
​
namespace Swag\BasicExample\Subscriber;
​
use Shopware\Core\Content\Product\ProductEntity;
use Shopware\Core\Framework\DataAbstractionLayer\Event\EntityLoadedEvent;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Shopware\Core\Content\Product\ProductEvents;
​
class ProductSubscriber implements EventSubscriberInterface
{
    public static function getSubscribedEvents(): array
    {
        return [
            ProductEvents::PRODUCT_LOADED_EVENT => 'onProductsLoaded'
        ];
    }
​
    public function onProductsLoaded(EntityLoadedEvent $event): void
    {
        /** @var ProductEntity $productEntity */
        foreach ($event->getEntities() as $productEntity) {
            $productEntity->addExtension('custom_string', new ArrayEntity(['foo' => 'bar']));
        }
    }
}
We're registering to the ProductEvents::PRODUCT_LOADED_EVENT event, which is fired everytime one or multiple products are requested. In the event listener method onProductsLoaded, we're then adding our own data to the new field via the method addExtension.
Please note that its second parameter, the actual value, has to be a struct and not just a string or other kind of scalar value.
After we've created our subscriber, we have to adjust our services.xml to register it. Below you can find our services.xml.
<plugin root>/src/Resources/config/services.xml
<?xml version="1.0" ?>
​
<container xmlns="http://symfony.com/schema/dic/services"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
​
    <services>
        <service id="Swag\BasicExample\Extension\Content\Product\CustomExtension">
            <tag name="shopware.entity.extension"/>
        </service>
​
        <service id="Swag\BasicExample\Subscriber\ProductSubscriber">
            <tag name="kernel.event_subscriber"/>
        </service>
    </services>
</container>
Entity extension vs. Custom fields
Custom fields are by default configurable by the admin user in the administration and they mostly support scalar types, e.g. a text-field, a number field or the likes. If you'd like to create associations between entities, you'll need to use an entity extension, just like we did here. Of course you can also add scalar values without an association to an entity via an extension.
Adding custom complex data
Replacing associated data
Last updated 5 days ago