Get categories of a table

Readme.md

Usage with

<xxx:category as="categories" id="{data.uid}" table="tt_content" field="categories" falField="images">
    <f:debug inline="1">{categories}</f:debug>
</xxx:category>

CategoryViewHelper.php

<?php
declare(strict_types=1);

namespace GeorgRinger\SitePackage\ViewHelpers;


use TYPO3\CMS\Core\Database\ConnectionPool;
use TYPO3\CMS\Core\Resource\FileRepository;
use TYPO3\CMS\Core\Utility\GeneralUtility;
use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;

class CategoryViewHelper extends AbstractViewHelper
{

    /**
     * @var bool
     */
    protected $escapeOutput = false;

    /**
     * Initialize arguments.
     */
    public function initializeArguments()
    {
        parent::initializeArguments();
        $this->registerArgument('as', 'string', 'as', true);
        $this->registerArgument('table', 'string', 'Table name of record', true);
        $this->registerArgument('field', 'string', 'Category field', true);
        $this->registerArgument('id', 'int', 'ID of record', true);
        $this->registerArgument('falField', 'string', 'Comma separated list of fal fields', false, '');
    }

    public function render(): string
    {
        $as = $this->arguments['as'];

        $categories = $this->getCategories($this->arguments);

        $this->templateVariableContainer->add($as, $categories);
        $output = $this->renderChildren();
        $this->templateVariableContainer->remove($as);
        return $output;
    }

    protected function getCategories(array $arguments): array
    {
        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable('sys_category');
        $rows = $queryBuilder
            ->select('s.*')
            ->from('sys_category', 's')
            ->rightJoin('s', 'sys_category_record_mm', 'mm', 's.uid=mm.uid_local')
            ->where(
                $queryBuilder->expr()->eq('mm.uid_foreign', $queryBuilder->createNamedParameter($arguments['id'], \PDO::PARAM_INT)),
                $queryBuilder->expr()->eq('mm.tablenames', $queryBuilder->createNamedParameter($arguments['table'], \PDO::PARAM_STR)),
                $queryBuilder->expr()->eq('mm.fieldname', $queryBuilder->createNamedParameter($arguments['field'], \PDO::PARAM_STR))
            )
            ->execute()
            ->fetchAll();

        if ($arguments['falField']) {
            $falFields = GeneralUtility::trimExplode(',', $arguments['falField'], true);

            foreach ($rows as &$row) {
                foreach ($falFields as $falField) {
                    if (!isset($row[$falField]) || (int)$row[$falField] === 0) {
                        continue;
                    }

                    try {
                        $fileObjects = GeneralUtility::makeInstance(FileRepository::class)
                            ->findByRelation('sys_category', $falField, $row['uid']);
                        $row[$falField] = $fileObjects;
                    } catch (\Exception $e) {
                        // do nothing
                    }
                }
            }
        }

        return $rows;
    }

}