Add category image with Magento REST API

Question

Has anyone successfully uploaded an image for use with a category? When going through the documentation @ http://devdocs.magento.com/swagger/index.html#/ I don't see any implementation that could support it.

Also when retrieving a category using Magento REST API you don't get the category image back.

In the admin page, you can add the category here:

Answer 1

At the moment this is not possible without extending core functionality. However, category image save/get support can be added to category REST API using extension attributes mechanism:

1. Declare extension attribute of string type for \Magento\Catalog\Api\Data\CategoryInterface (it will hold base64-encoded image)
2. Write afterSave plugin for \Magento\Catalog\Api\CategoryRepositoryInterface::save to save image
3. Write afterLoad plugin for \Magento\Catalog\Api\CategoryRepositoryInterface::get to load image

See more detailed instructions on declaring extension attributes in this answer

Answer 2

Here's an example how you can extend Magento functionality to import the category thumbnail image of a category using extension attribute with base64 string. You can adjust it per your own requirements.

Vendor/Module/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\Catalog\Api\Data\CategoryInterface">
        <attribute code="thumbnail_name" type="string"/>
        <attribute code="thumbnail_base64_string" type="string"/>
    </extension_attributes>
</config>

Vendor/Module/etc/webapi_rest/di.xml:

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <type name="Magento\Catalog\Model\CategoryRepository">
        <plugin name="category_process_base64_thumbnail" type="Vendor\Module\Plugin\Model\CategoryRepositoryPlugin"/>
    </type>
</config>

Vendor/Module/Plugin/Model/CategoryRepositoryPlugin:

<?php

declare(strict_types=1);

namespace Vendor\Module\Plugin\Model;

use Magento\Catalog\Api\Data\CategoryExtension;
use Magento\Catalog\Api\Data\CategoryInterface;
use Magento\Catalog\Model\CategoryRepository;
use Magento\Framework\Api\Data\ImageContentInterface;
use Magento\Framework\Api\ImageProcessorInterface;
use Magento\Framework\App\Filesystem\DirectoryList;
use Magento\Framework\Exception\InputException;

class CategoryRepositoryPlugin
{
    public function __construct(
        private readonly ImageContentInterface $imageContent,
        private readonly ImageProcessorInterface $imageProcessor
    ) {
    }

    /**
     * @param CategoryRepository $subject
     * @param CategoryInterface  $category
     *
     * @return CategoryInterface[]|null
     */
    public function beforeSave(CategoryRepository $subject, CategoryInterface $category): ?array
    {
        /** @var CategoryExtension $categoryExtensionAttributes */
        $categoryExtensionAttributes = $category->getExtensionAttributes();

        $this->imageContent
            ->setName($categoryExtensionAttributes->getThumbnailName())
            ->setBase64EncodedData($categoryExtensionAttributes->getThumbnailBase64String())
            ->setType('image/jpeg');

        try {
            $entityType = 'catalog/category';
            $uploadedFileName = $this->imageProcessor->processImageContent(
                $entityType,
                $this->imageContent
            );
        } catch (InputException $e) {
            return null;
        }

        /** @var \Magento\Catalog\Model\Category $category */
        $category->setData(
            'thumbnail',
            DIRECTORY_SEPARATOR . DirectoryList::MEDIA . DIRECTORY_SEPARATOR . $entityType . $uploadedFileName
        );

        return [$category];
    }
}

Also at the Vendor/Module/registration.php and Vendor/Module/etc/module.xml files and run bin/magento setup:upgrade and bin/magento cache:flush.

After that you can do a POST request to categories endpoint with payload like:

{
  "category": {
    "parent_id": 2,
    "name": "Category Test",
    "is_active": true,
    "level": 1,
        "extension_attributes": {
            "thumbnail_name": "category-test-thumbnail.jpeg",
            "thumbnail_base64_string": "/9j/....."
        }
    }
}

The image will be saved as pub/media/catalog/category/category-test-thumbnail.jpeg and added as thumbnail image to the category.