Cart Snippets - Snippets collection for my TYPO3 extensions Cart and Cart*

31 Mar 2017

How to extend product models (part one)

This blog post is the first of a planned series about extending Cart product models.

Extending models is nothing special and can be applied to other extensions and extbase models as well. I will create a further extension (CartExtendedProduct) in parallel to writing this post and, in addition, provide a Link to the repository at the end of this article.

I won’t use the extension builder, so we will have to create some directories and files on our own. In the repository, I will add a composer.json file and some other files, but I will ignore them in my post because they don’t have an effect on the function.

The addition of a manufacturer field seems to be a useful target for this extension. To make it as simple as possible, I will limit the type of the new field to a string.

1. File structure

└─── Classes 
│    │
│    └─── Domain 
│         │
│         └─── Model
│              │
│              └─── Product
│                   └─── Product.php
└─── Configuration 
│    │
│    └─── TCA 
│    │    │
│    │    └─── Overrides
|    |         └─── tx_cart_domain_model_product_product.php
│    │
│    └─── TypoScript
│         └─── setup.txt
└─── Resources 
│    │
│    └─── Private 
│         │
│         └─── Language
|              └─── de.locallang_db.xlf
|              └─── locallang_db.xlf
└─── Tests 
│    │
│    └─── Unit 
│         │
│         └─── Domain 
│              │
│              └─── Model
│                   │
│                   └─── Product
│                        └─── ProductTest.php
└─── ext_emconf.php 
└─── ext_tables.sql   

After creating this structure, start to fill the files with some code.

2. Extend the database, TCA and model

2.1. Extend the database

Add the new database field ‘manufacturer’.


# Table structure for table 'tx_cart_domain_model_product_product'
CREATE TABLE tx_cart_domain_model_product_product (
    manufacturer varchar(255) DEFAULT '' NOT NULL,

2.2. Extend the TCA

In ‘TCA/Overrides’, add the configuration file for the new field. It must have the same filename as the configuration it extends.


$temporaryColumns = [
    'manufacturer' => [
        'exclude' => 1,
        'label' => $_LLL . ':tx_cart_domain_model_product_product.manufacturer',
        'config' => [
            'type' => 'input',
            'size' => 30,
            'eval' => 'trim'


This is quite simple. I will skip the content of the translation files here.

After updating the the database through the InstallTool and clearing the cache, the new field should be available in the backend forms next to the title.

edit the extended product in backend

2.3. Extend the product model

Next, the getter and setter functions in the product model has to be provided by this extension.


namespace Extcode\CartExtendedProduct\Domain\Model\Product;

class Product extends \Extcode\Cart\Domain\Model\Product\Product
    protected $manufacturer = '';

    public function getManufacturer()
        return $this->manufacturer;

    public function setManufacturer($manufacturer)
        $this->manufacturer = $manufacturer;

The new \Extcode\CartExtendedProduct\Domain\Model\Product extends the \Extcode\Cart\Domain\Model\Product\Product. Please note that extra \Product in the namespace because in the second part of this article, I will extend other product models too. This is also represented by grouping the models in folders.

3. Extbase should use the new product model

3.1. TypoScript configuration

The most important thing is to tell extbase to use the new product model.

config.tx_extbase {
    persistence {
        classes {
            Extcode\CartExtendedProduct\Domain\Model\Product\Product {
                mapping {
                    tableName = tx_cart_domain_model_product_product
                    recordType =
    objects {
        Extcode\Cart\Domain\Model\Product\Product.className   = Extcode\CartExtendedProduct\Domain\Model\Product\Product

Because the extended product model do not have it’s own database table, the persistence array tells extbase to use the extended database table. The objects array tells extbase to use the Extcode\CartExtendedProduct\Domain\Model\Product\Product whenever an instance of Extcode\Cart\Domain\Model\Product\Product is used. That’s why the new getter function can be used in the template files.

3.2. Templating

After clearing the cache, the new getter appears in the Fluid template. I added the {product.manufacturer} after the product title in my own project template file.

edit the extended product in backend

4. Limitations

Because of the configuration in TypoScript, it is possible to extend the product model only once. This shouldn’t be a problem as long as no third party extension extends the models.

5. Conclusion

In most cases, it is very easy to extend the product model. You can extend other models as well.

7. Outlook for the next post

Sometimes, the product’s attribute must available in the order, so in the next post, I will show you how to transfer a new product attribute to the order item.

extcode at 09:53