TYPO3 v15 dev-main snapshot ()

Classes/ElementBrowser/AbstractElementBrowser.php

@@ -0,0 +1,144 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+namespace TYPO3\CMS\Backend\ElementBrowser;
+
+use Psr\Http\Message\ServerRequestInterface;
+use TYPO3\CMS\Backend\Routing\UriBuilder;
+use TYPO3\CMS\Backend\Template\Components\ComponentFactory;
+use TYPO3\CMS\Backend\Template\PageRendererBackendSetupTrait;
+use TYPO3\CMS\Backend\View\BackendViewFactory;
+use TYPO3\CMS\Core\Authentication\BackendUserAuthentication;
+use TYPO3\CMS\Core\Configuration\ExtensionConfiguration;
+use TYPO3\CMS\Core\Imaging\IconFactory;
+use TYPO3\CMS\Core\Localization\LanguageService;
+use TYPO3\CMS\Core\Page\PageRenderer;
+use TYPO3\CMS\Core\Schema\TcaSchemaFactory;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Core\View\ViewInterface;
+
+/**
+ * Base class for element browsers
+ * This class should only be used internally. Extensions must implement the ElementBrowserInterface.
+ *
+ * @internal This class is a specific LinkBrowser implementation and is not part of the TYPO3's Core API.
+ */
+abstract class AbstractElementBrowser
+{
+    use PageRendererBackendSetupTrait;
+
+    /**
+     * The element browsers unique identifier
+     */
+    protected string $identifier = '';
+
+    /**
+     * Typed DTO containing all browser parameters.
+     */
+    protected ElementBrowserParameters $browserParameters;
+
+    protected ?ServerRequestInterface $request = null;
+    protected ViewInterface $view;
+
+    public function __construct(
+        protected readonly IconFactory $iconFactory,
+        protected readonly PageRenderer $pageRenderer,
+        protected readonly UriBuilder $uriBuilder,
+        protected readonly ExtensionConfiguration $extensionConfiguration,
+        protected readonly BackendViewFactory $backendViewFactory,
+        protected readonly TcaSchemaFactory $tcaSchemaFactory,
+        protected readonly ComponentFactory $componentFactory,
+    ) {}
+
+    /**
+     * Main initialization
+     */
+    protected function initialize(ServerRequestInterface $request)
+    {
+        $this->setUpBasicPageRendererForBackend($this->pageRenderer, $this->extensionConfiguration, $this->getRequest(), $this->getLanguageService());
+        $view = $this->backendViewFactory->create($request);
+        $this->view = $view;
+        $this->pageRenderer->loadJavaScriptModule('@typo3/backend/element-browser.js');
+        $this->pageRenderer->loadJavaScriptModule('@typo3/backend/hotkeys.js');
+        $this->pageRenderer->addInlineLanguageLabelFile('EXT:core/Resources/Private/Language/locallang_misc.xlf');
+        $this->pageRenderer->addInlineLanguageLabelFile('EXT:core/Resources/Private/Language/locallang_core.xlf');
+        $this->initVariables($request);
+    }
+
+    /**
+     * Returns the identifier for the browser
+     */
+    public function getIdentifier(): string
+    {
+        return $this->identifier;
+    }
+
+    protected function initVariables(ServerRequestInterface $request)
+    {
+        $this->browserParameters = ElementBrowserParameters::fromRequest($request);
+    }
+
+    protected function getBodyTagParameters(): string
+    {
+        $bodyDataAttributes = array_merge(
+            $this->getBParamDataAttributes(),
+            $this->getBodyTagAttributes()
+        );
+        return GeneralUtility::implodeAttributes($bodyDataAttributes, true, true);
+    }
+
+    /**
+     * @return array<string, string> Array of body-tag attributes
+     */
+    protected function getBodyTagAttributes()
+    {
+        return [];
+    }
+
+    /**
+     * Returns data attributes for the body tag, used by the Javascript.
+     *
+     * @return array<string, string|null> Data attributes for Javascript
+     */
+    protected function getBParamDataAttributes()
+    {
+        return $this->browserParameters->toDataAttributes();
+    }
+
+    public function setRequest(ServerRequestInterface $request): void
+    {
+        $this->request = $request;
+        // initialize here, this is a dirty hack as long as the interface does not support setting a request object properly
+        // see ElementBrowserController.php for the process on how the program code flow is used
+        $this->initialize($request);
+    }
+
+    protected function getRequest(): ServerRequestInterface
+    {
+        return $this->request ?? $GLOBALS['TYPO3_REQUEST'];
+    }
+
+    protected function getLanguageService(): LanguageService
+    {
+        return $GLOBALS['LANG'];
+    }
+
+    protected function getBackendUser(): BackendUserAuthentication
+    {
+        return $GLOBALS['BE_USER'];
+    }
+}

Classes/ElementBrowser/DatabaseBrowser.php

@@ -0,0 +1,248 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+namespace TYPO3\CMS\Backend\ElementBrowser;
+
+use Psr\Http\Message\ServerRequestInterface;
+use TYPO3\CMS\Backend\Module\ModuleData;
+use TYPO3\CMS\Backend\RecordList\ElementBrowserRecordList;
+use TYPO3\CMS\Backend\Tree\View\LinkParameterProviderInterface;
+use TYPO3\CMS\Backend\Utility\BackendUtility;
+use TYPO3\CMS\Backend\View\RecordSearchBoxComponent;
+use TYPO3\CMS\Core\Imaging\IconSize;
+use TYPO3\CMS\Core\Schema\Capability\TcaSchemaCapability;
+use TYPO3\CMS\Core\Type\Bitmask\Permission;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Core\Utility\MathUtility;
+
+/**
+ * Showing a page tree and allows you to browse for records. This is the modal rendered
+ * for type=group to add db relations to a group field.
+ *
+ * @internal This class is a specific LinkBrowser implementation and is not part of the TYPO3's Core API.
+ */
+class DatabaseBrowser extends AbstractElementBrowser implements ElementBrowserInterface, LinkParameterProviderInterface
+{
+    protected string $identifier = 'db';
+
+    /**
+     * When you click a page title/expand icon to see the content of a certain page, this
+     * value will contain the ID of the expanded page.
+     * If the value is NOT set by GET parameter, then it will be restored from the module session data.
+     *
+     * @var int|null
+     */
+    protected $expandPage;
+    protected array $modTSconfig = [];
+
+    protected function initialize(ServerRequestInterface $request)
+    {
+        parent::initialize($request);
+        $this->pageRenderer->loadJavaScriptModule('@typo3/backend/browse-database.js');
+        $this->pageRenderer->loadJavaScriptModule('@typo3/backend/tree/page-browser.js');
+        $this->pageRenderer->loadJavaScriptModule('@typo3/backend/column-selector-button.js');
+        $this->pageRenderer->loadJavaScriptModule('@typo3/backend/recordlist.js');
+        $this->pageRenderer->loadJavaScriptModule('@typo3/backend/record-search.js');
+    }
+
+    protected function initVariables(ServerRequestInterface $request)
+    {
+        parent::initVariables($request);
+        $this->expandPage = $request->getParsedBody()['expandPage'] ?? $request->getQueryParams()['expandPage'] ?? null;
+    }
+
+    /**
+     * Session data for this class can be set from outside with this method.
+     *
+     * @param mixed[] $data Session data array
+     * @return array<int, array|bool> Session data and boolean which indicates that data needs to be stored in session because it's changed
+     */
+    public function processSessionData($data)
+    {
+        if ($this->expandPage !== null) {
+            $data['expandPage'] = $this->expandPage;
+            $store = true;
+        } else {
+            $this->expandPage = (int)($data['expandPage'] ?? 0);
+            $store = false;
+        }
+        return [$data, $store];
+    }
+
+    /**
+     * @return string HTML content
+     */
+    public function render()
+    {
+        $this->getBackendUser()->initializeWebmountsForElementBrowser();
+        $this->modTSconfig = BackendUtility::getPagesTSconfig((int)$this->expandPage)['mod.']['web_list.'] ?? [];
+        $allowedTables = $this->browserParameters->allowedTypes;
+
+        $withTree = true;
+        if ($allowedTables !== '' && $allowedTables !== '*') {
+            $tablesArr = GeneralUtility::trimExplode(',', $allowedTables, true);
+            $onlyRootLevel = true;
+            foreach ($tablesArr as $currentTable) {
+                if ($this->tcaSchemaFactory->has($currentTable)) {
+                    $schema = $this->tcaSchemaFactory->get($currentTable);
+                    if ($schema->getCapability(TcaSchemaCapability::RestrictionRootLevel)->canExistOnPages()) {
+                        $onlyRootLevel = false;
+                        break;
+                    }
+                }
+            }
+            if ($onlyRootLevel) {
+                $withTree = false;
+                // page to work on is root
+                $this->expandPage = 0;
+            }
+        }
+
+        $contentOnly = (bool)($this->getRequest()->getQueryParams()['contentOnly'] ?? false);
+        $renderedRecordList = $this->renderTableRecords($allowedTables);
+
+        $this->pageRenderer->setTitle($this->getLanguageService()->sL('LLL:EXT:backend/Resources/Private/Language/locallang_browse_links.xlf:recordSelector'));
+        $view = $this->view;
+        $view->assignMultiple([
+            'treeEnabled' => $withTree,
+            'treeActions' => $allowedTables === 'pages' ? ['select'] : [],
+            'activePage' => $this->expandPage,
+            'initialNavigationWidth' => $this->getBackendUser()->uc['selector']['navigation']['width'] ?? 250,
+            'content' => $renderedRecordList,
+            'contentOnly' => $contentOnly,
+        ]);
+        $content = $this->view->render('ElementBrowser/Page');
+        if ($contentOnly) {
+            return $content;
+        }
+        $this->pageRenderer->setBodyContent('<body ' . $this->getBodyTagParameters() . '>' . $content);
+        return $this->pageRenderer->render($this->getRequest());
+    }
+
+    /**
+     * This lists all content elements for the given list of tables
+     *
+     * @param string $tables Comma separated list of tables. Set to "*" if you want all tables.
+     * @return string HTML code
+     */
+    protected function renderTableRecords($tables)
+    {
+        $request = $this->getRequest();
+        $backendUser = $this->getBackendUser();
+        if ($this->expandPage === null || $this->expandPage < 0 || !$backendUser->isInWebMount($this->expandPage)) {
+            return '';
+        }
+        // Set array with table names to list:
+        if (trim($tables) === '*') {
+            $tablesArr = $this->tcaSchemaFactory->all()->getNames();
+        } else {
+            $tablesArr = GeneralUtility::trimExplode(',', $tables, true);
+        }
+
+        $out = '';
+        // Create the header, showing the current page for which the listing is.
+        // Includes link to the page itself, if pages are amount allowed tables.
+        $mainPageRecord = BackendUtility::getRecordWSOL('pages', $this->expandPage);
+        if (is_array($mainPageRecord)) {
+            $pText = htmlspecialchars(BackendUtility::cropToTitleLength($mainPageRecord['title']));
+
+            $out .= '<p>' . $this->iconFactory->getIconForRecord('pages', $mainPageRecord, IconSize::SMALL)->render() . '&nbsp;';
+            if (in_array('pages', $tablesArr, true)) {
+                $out .= '<span data-uid="' . htmlspecialchars((string)$mainPageRecord['uid']) . '" data-table="pages" data-title="' . htmlspecialchars($mainPageRecord['title']) . '">';
+                $out .= '<a href="#" data-close="0">'
+                    . $this->iconFactory->getIcon('actions-plus', IconSize::SMALL)->render()
+                    . '</a>'
+                    . '<a href="#" data-close="1">'
+                    . $pText
+                    . '</a>';
+                $out .= '</span>';
+            } else {
+                $out .= $pText;
+            }
+            $out .= '</p>';
+        }
+
+        $permsClause = $backendUser->getPagePermsClause(Permission::PAGE_SHOW);
+        $pageInfo = BackendUtility::readPageAccess($this->expandPage, $permsClause);
+        $existingModuleData = $backendUser->getModuleData('records');
+        $moduleData = new ModuleData('records', is_array($existingModuleData) ? $existingModuleData : []);
+
+        $dbList = GeneralUtility::makeInstance(ElementBrowserRecordList::class);
+        $dbList->setRequest($request);
+        $dbList->setModuleData($moduleData);
+        $dbList->setOverrideUrlParameters($this->getUrlParameters([]), $request);
+        $dbList->setIsEditable(false);
+        $dbList->calcPerms = new Permission($backendUser->calcPerms($pageInfo));
+        $dbList->noControlPanels = true;
+        $dbList->clickMenuEnabled = false;
+        $dbList->displayRecordDownload = false;
+        $dbList->tableList = implode(',', $tablesArr);
+
+        // Extract relating table and field from field reference (e.g., "data[pages][79][storage_pid]")
+        $fieldReferenceParts = $this->browserParameters->getFieldReferenceParts();
+        if ($fieldReferenceParts['tableName'] !== '' && $fieldReferenceParts['fieldName'] !== '') {
+            $dbList->setRelatingTableAndField($fieldReferenceParts['tableName'], $fieldReferenceParts['fieldName']);
+        }
+
+        $selectedTable = (string)($request->getParsedBody()['table'] ?? $request->getQueryParams()['table'] ?? '');
+        $searchWord = (string)($request->getParsedBody()['searchTerm'] ?? $request->getQueryParams()['searchTerm'] ?? '');
+        $searchLevels = (int)($request->getParsedBody()['search_levels'] ?? $request->getQueryParams()['search_levels'] ?? $this->modTSconfig['searchLevel.']['default'] ?? 0);
+        $pointer = (int)($request->getParsedBody()['pointer'] ?? $request->getQueryParams()['pointer'] ?? 0);
+
+        $dbList->start(
+            (int)$this->expandPage,
+            $selectedTable,
+            MathUtility::forceIntegerInRange($pointer, 0, 100000),
+            $searchWord,
+            $searchLevels
+        );
+
+        $tableList = $dbList->generateList();
+
+        $out .= $this->renderSearchBox($request, $dbList, $searchWord, $searchLevels);
+
+        // Add the HTML for the record list to output variable:
+        $out .= $tableList;
+
+        return $out;
+    }
+
+    protected function renderSearchBox(ServerRequestInterface $request, ElementBrowserRecordList $dblist, string $searchWord, int $searchLevels): string
+    {
+        return GeneralUtility::makeInstance(RecordSearchBoxComponent::class)
+            ->setAllowedSearchLevels((array)($this->modTSconfig['searchLevel.']['items.'] ?? []))
+            ->setSearchWord($searchWord)
+            ->setSearchLevel($searchLevels)
+            ->render($request, $dblist->listURL('', null, 'pointer,searchTerm'));
+    }
+
+    /**
+     * @param array $values Array of values to include into the parameters
+     * @return array<string,mixed> Array of parameters which have to be added to URLs
+     */
+    public function getUrlParameters(array $values): array
+    {
+        $pid = $values['pid'] ?? $this->expandPage;
+        return array_merge(
+            [
+                'mode' => 'db',
+                'expandPage' => $pid,
+            ],
+            $this->browserParameters->toQueryParameters()
+        );
+    }
+}

Classes/ElementBrowser/ElementBrowserInterface.php

@@ -0,0 +1,46 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+namespace TYPO3\CMS\Backend\ElementBrowser;
+
+/**
+ * Element browsers are modals rendered when records are attached to FormEngine elements.
+ * Core usages:
+ * * Managing TCA type=file relations
+ * * Managing FAL folder relations a TCA type=folder
+ * * Managing various target relations of a TCA type=group
+ */
+interface ElementBrowserInterface
+{
+    /**
+     * Returns the unique identifier of the element browser
+     */
+    public function getIdentifier(): string;
+
+    /**
+     * @return string HTML content
+     */
+    public function render();
+
+    /**
+     * Session data for this class can be set from outside with this method.
+     *
+     * @param mixed[] $data Session data array
+     * @return array[] Session data and boolean which indicates that data needs to be stored in session because it's changed
+     */
+    public function processSessionData($data);
+}

Classes/ElementBrowser/ElementBrowserParameters.php

@@ -0,0 +1,220 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+namespace TYPO3\CMS\Backend\ElementBrowser;
+
+use Psr\Http\Message\ServerRequestInterface;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Data Transfer Object for Element Browser parameters.
+ *
+ * Provides type-safe access to the parameters passed between FormEngine and
+ * the Element Browser.
+ *
+ * @internal This class is not part of the TYPO3 Core API.
+ */
+final readonly class ElementBrowserParameters implements \JsonSerializable
+{
+    /**
+     * @param string $fieldReference Form field name reference, e.g., "data[tt_content][123][image]"
+     * @param string $allowedTypes Allowed types: tables (comma-separated) for db mode, or file extensions for file mode
+     * @param string $disallowedFileExtensions Disallowed file extensions (comma-separated) for file mode
+     * @param string $irreObjectId IRRE uniqueness target, e.g., "data-4-pages-4-nav_icon-sys_file_reference"
+     */
+    public function __construct(
+        public string $fieldReference = '',
+        public string $allowedTypes = '',
+        public string $disallowedFileExtensions = '',
+        public string $irreObjectId = '',
+        public bool $useEvents = false,
+    ) {}
+
+    /**
+     * Creates an instance from the current HTTP request.
+     */
+    public static function fromRequest(ServerRequestInterface $request): self
+    {
+        $queryParams = $request->getQueryParams();
+        $parsedBody = $request->getParsedBody() ?? [];
+
+        return new self(
+            fieldReference: (string)($parsedBody['fieldReference'] ?? $queryParams['fieldReference'] ?? ''),
+            allowedTypes: (string)($parsedBody['allowedTypes'] ?? $queryParams['allowedTypes'] ?? ''),
+            disallowedFileExtensions: (string)($parsedBody['disallowedFileExtensions'] ?? $queryParams['disallowedFileExtensions'] ?? ''),
+            irreObjectId: (string)($parsedBody['irreObjectId'] ?? $queryParams['irreObjectId'] ?? ''),
+            useEvents: (bool)(int)($parsedBody['useEvents'] ?? $queryParams['useEvents'] ?? 0),
+        );
+    }
+
+    /**
+     * Returns the allowed file extensions as an array.
+     *
+     * @return string[] List of allowed file extensions
+     */
+    public function getAllowedFileExtensions(): array
+    {
+        if ($this->allowedTypes === '' || $this->allowedTypes === '*') {
+            return [];
+        }
+
+        // Skip if it looks like a table name (contains underscore typical for TYPO3 tables)
+        if (str_contains($this->allowedTypes, 'sys_file')) {
+            return [];
+        }
+
+        return GeneralUtility::trimExplode(',', $this->allowedTypes, true);
+    }
+
+    /**
+     * Returns the disallowed file extensions as an array.
+     *
+     * @return string[] List of disallowed file extensions
+     */
+    public function getDisallowedFileExtensions(): array
+    {
+        if ($this->disallowedFileExtensions === '') {
+            return [];
+        }
+
+        return GeneralUtility::trimExplode(',', $this->disallowedFileExtensions, true);
+    }
+
+    /**
+     * Parses the allowed file extensions from the allowedTypes field.
+     *
+     * @return array{allowed: string[], disallowed: string[]}
+     */
+    public function getFileExtensions(): array
+    {
+        return [
+            'allowed' => $this->getAllowedFileExtensions(),
+            'disallowed' => $this->getDisallowedFileExtensions(),
+        ];
+    }
+
+    /**
+     * Parses the allowed tables from the allowedTypes field.
+     *
+     * @return string[] List of allowed table names
+     */
+    public function getAllowedTables(): array
+    {
+        if ($this->allowedTypes === '' || $this->allowedTypes === '*') {
+            return [];
+        }
+
+        return GeneralUtility::trimExplode(',', $this->allowedTypes, true);
+    }
+
+    /**
+     * Returns the field reference parsed into table name and field name.
+     *
+     * Parses format like "data[tt_content][123][image]" to extract
+     * table name ("tt_content") and field name ("image").
+     *
+     * @return array{tableName: string, fieldName: string}
+     */
+    public function getFieldReferenceParts(): array
+    {
+        $result = [
+            'tableName' => '',
+            'fieldName' => '',
+        ];
+
+        if ($this->fieldReference === '') {
+            return $result;
+        }
+
+        // Parse "data[table][uid][field]" format
+        $parts = explode('[', $this->fieldReference);
+        if (count($parts) >= 4) {
+            // parts[1] = "table]", parts[3] = "field]"
+            $result['tableName'] = rtrim($parts[1], ']');
+            $result['fieldName'] = rtrim($parts[3], ']');
+        }
+
+        return $result;
+    }
+
+    /**
+     * Returns data attributes for use in HTML elements (body tag).
+     *
+     * @return array<string, string|null>
+     */
+    public function toDataAttributes(): array
+    {
+        return [
+            'data-field-reference' => $this->fieldReference,
+            'data-irre-object-id' => $this->irreObjectId ?: null,
+            'data-use-events' => $this->useEvents ? 'true' : null,
+        ];
+    }
+
+    /**
+     * Returns array representation of the parameters.
+     *
+     * @return array{
+     *   fieldReference: string,
+     *   allowedTypes: string,
+     *   disallowedFileExtensions: string,
+     *   irreObjectId: string,
+     *   useEvents: bool
+     * }
+     */
+    public function toArray(): array
+    {
+        return [
+            'fieldReference' => $this->fieldReference,
+            'allowedTypes' => $this->allowedTypes,
+            'disallowedFileExtensions' => $this->disallowedFileExtensions,
+            'irreObjectId' => $this->irreObjectId,
+            'useEvents' => $this->useEvents,
+        ];
+    }
+
+    /**
+     * Returns URL query parameters array (new format).
+     *
+     * @return array<string, string>
+     */
+    public function toQueryParameters(): array
+    {
+        $params = [];
+        if ($this->fieldReference !== '') {
+            $params['fieldReference'] = $this->fieldReference;
+        }
+        if ($this->allowedTypes !== '') {
+            $params['allowedTypes'] = $this->allowedTypes;
+        }
+        if ($this->disallowedFileExtensions !== '') {
+            $params['disallowedFileExtensions'] = $this->disallowedFileExtensions;
+        }
+        if ($this->irreObjectId !== '') {
+            $params['irreObjectId'] = $this->irreObjectId;
+        }
+        if ($this->useEvents) {
+            $params['useEvents'] = '1';
+        }
+        return $params;
+    }
+
+    public function jsonSerialize(): array
+    {
+        return $this->toArray();
+    }
+}

Classes/ElementBrowser/ElementBrowserRegistry.php

@@ -0,0 +1,79 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+namespace TYPO3\CMS\Backend\ElementBrowser;
+
+/**
+ * Registry for element browsers. The registry receives all services, tagged with "recordlist.elementbrowser".
+ * The tagging of element browsers is automatically done based on the implemented ElementBrowserInterface.
+ *
+ * @internal
+ */
+class ElementBrowserRegistry
+{
+    /**
+     * @var ElementBrowserInterface[]
+     */
+    private array $elementBrowsers = [];
+
+    public function __construct(iterable $elementBrowsers)
+    {
+        foreach ($elementBrowsers as $elementBrowser) {
+            if (!($elementBrowser instanceof ElementBrowserInterface)) {
+                continue;
+            }
+
+            $identifier = $elementBrowser->getIdentifier();
+            if ($identifier === '') {
+                throw new \InvalidArgumentException('Identifier for element browser ' . get_class($elementBrowser) . ' is empty.', 1647241084);
+            }
+            if (isset($this->elementBrowsers[$identifier])) {
+                throw new \InvalidArgumentException('Element browser with identifier ' . $identifier . ' is already registered.', 1647241085);
+            }
+            $this->elementBrowsers[$identifier] = $elementBrowser;
+        }
+    }
+
+    /**
+     * Whether a registered element browser exists for the identifier
+     */
+    public function hasElementBrowser(string $identifier): bool
+    {
+        return isset($this->elementBrowsers[$identifier]);
+    }
+
+    /**
+     * Get registered element browser by identifier
+     */
+    public function getElementBrowser(string $identifier): ElementBrowserInterface
+    {
+        if (!$this->hasElementBrowser($identifier)) {
+            throw new \UnexpectedValueException('Element browser with identifier ' . $identifier . ' is not registered.', 1647241086);
+        }
+        return $this->elementBrowsers[$identifier];
+    }
+
+    /**
+     * Get all registered element browsers
+     *
+     * @return ElementBrowserInterface[]
+     */
+    public function getElementBrowsers(): array
+    {
+        return $this->elementBrowsers;
+    }
+}

Classes/ElementBrowser/Event/IsFileSelectableEvent.php

@@ -0,0 +1,52 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+namespace TYPO3\CMS\Backend\ElementBrowser\Event;
+
+use TYPO3\CMS\Core\Resource\FileInterface;
+
+/**
+ * Listeners to this event are able to define whether a file can be selected in the file browser
+ */
+final class IsFileSelectableEvent
+{
+    private bool $isFileSelectable = true;
+
+    public function __construct(
+        private readonly FileInterface $file,
+    ) {}
+
+    public function getFile(): FileInterface
+    {
+        return $this->file;
+    }
+
+    public function isFileSelectable(): bool
+    {
+        return $this->isFileSelectable;
+    }
+
+    public function allowFileSelection(): void
+    {
+        $this->isFileSelectable = true;
+    }
+
+    public function denyFileSelection(): void
+    {
+        $this->isFileSelectable = false;
+    }
+}