Unfortunatly I didn't find any API to get hex or image of visual swatch attribute. After playing a bit i write a module which use extension attribute for AttributeInterface.... I've tried with AttributeOptionInterface but without success.
After the module is installed is possible to fetch hex or image by checking the extension_attributes for these API calls:
http://domain.com/index.php/rest/it/V1/products/attributes?searchCriteria[filter_groups][0][filters][0][field]=attribute_code&searchCriteria[filter_groups][0][filters][0][value]=color
http://domain.com/index.php/rest/it/V1/products/attributes/93/
Tested with Magento 2.3.2
app/code/ProjectName/ModuleName/registration.php
<?php
\Magento\Framework\Component\ComponentRegistrar::register(
\Magento\Framework\Component\ComponentRegistrar::MODULE,
'ProjectName_ModuleName',
__DIR__
);
app/code/ProjectName/ModuleName/etc/module.xml
<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Module/etc/module.xsd">
<module name="ProjectName_ModuleName" setup_version="1.0.0">
</module>
</config>
app/code/ProjectName/ModuleName/etc/extension_attributes.xml
<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Api/etc/extension_attributes.xsd">
<extension_attributes for="Magento\Eav\Api\Data\AttributeInterface">
<attribute code="product_attribute_option_swatch" type="ProjectName\ModuleName\Api\Data\AttributeSwatchOptionInterface[]" />
</extension_attributes>
</config>
Create AttributeSwatchOptionInterface and Model
app/code/ProjectName/ModuleName/Api/Data/AttributeSwatchOptionInterface.php
<?php
namespace ProjectName\ModuleName\Api\Data;
use Magento\Eav\Api\Data\AttributeOptionInterface;
interface AttributeSwatchOptionInterface extends AttributeOptionInterface
{
/**
* Constants used as data array keys
*/
const TYPE = 'type';
const SWATCHVALUE = 'swatch_value';
/**
* Get option label
*
* @return string
*/
public function getType();
/**
* Set option label
*
* @param string $label
* @return $this
*/
public function setType($type);
/**
* Get option value
*
* @return string
*/
public function getSwatchValue();
/**
* Set option value
*
* @param string $value
* @return string
*/
public function setSwatchValue($swatch_value);
}
app/code/ProjectName/ModuleName/Model/AttributeSwatchOption.php
<?php
namespace ProjectName\ModuleName\Model;
use ProjectName\ModuleName\Api\Data\AttributeSwatchOptionInterface;
use Magento\Eav\Model\Entity\Attribute\Option;
class AttributeSwatchOption extends Option implements AttributeSwatchOptionInterface
{
/**
* Resource initialization
*
* @return void
*/
public function _construct()
{
parent::__construct();
}
public function getType()
{
return $this->getData(AttributeSwatchOptionInterface::TYPE);
}
public function getSwatchValue()
{
return $this->getData(AttributeSwatchOptionInterface::SWATCHVALUE);
}
public function setType($type)
{
return $this->setData(AttributeSwatchOptionInterface::TYPE, $type);
}
public function setSwatchValue($value)
{
return $this->setData(AttributeSwatchOptionInterface::SWATCHVALUE, $swatch_value);
}
Now we add an observe for event catalog_entity_attribute_load_after
app/code/ProjectName/ModuleName/etc/events.xml
<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Event/etc/events.xsd">
<event name="catalog_entity_attribute_load_after">
<observer name="projectname_product_attribute_option_swatch" instance="ProjectName\ModuleName\Observer\OptionSwatchLoadAfter" />
</event>
</config>
app/code/ProjectName/ModuleName/Observer/OptionSwatchLoadAfter.php
<?php
namespace ProjectName\ModuleName\Observer;
use Magento\Framework\Event\Observer as EventObserver;
use Magento\Framework\Event\ObserverInterface;
use Psr\Log\LoggerInterface as Logger;
use Magento\Swatches\Helper\Data as SwatchHelper;
use Magento\Eav\Api\Data\AttributeInterface;
class OptionSwatchLoadAfter implements ObserverInterface
{
/**
* @var Logger
*/
protected $_logger;
protected $_swatchHelper;
public function __construct(Logger $logger, SwatchHelper $swatchHelper)
{
$this->_logger = $logger;
$this->_swatchHelper = $swatchHelper;
}
/**
* @param EventObserver $observer
* @return $this
* @throws \Exception
*/
public function execute(EventObserver $observer)
{
$attribute = $observer->getEvent()->getData('attribute');
$extensionAttributes = $attribute->getExtensionAttributes();
//isVisualSwatch
if ($this->_swatchHelper->isVisualSwatch($attribute))
{
$options = $attribute->getOptions();
$options = $this->processOptions($options);
$extensionAttributes->setProductAttributeOptionSwatch($options);
$attribute->setExtensionAttributes($extensionAttributes);
}
return $this;
}
private function processOptions($options)
{
$option_ids = array();
foreach($options as $option)
{
$option_ids[] = $option->getValue();
}
$swatches = $this->_swatchHelper->getSwatchesByOptionsId($option_ids);
if (count($swatches) > 0)
{
foreach($options as $option)
{
if (isset($swatches[$option->getValue()]))
{
$swatch = $swatches[$option->getValue()];
$option->setType($swatch['type']);
$option->setSwatchValue($swatch['value']);
}
}
}
return $options;
}
}