first commit

typo3/sysext/backend/Classes/Backend/ToolbarItems/ClearCacheToolbarItem.php

@@ -0,0 +1,208 @@
+<?php
+namespace TYPO3\CMS\Backend\Backend\ToolbarItems;
+
+/*
+ * 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!
+ */
+
+use TYPO3\CMS\Backend\Routing\UriBuilder;
+use TYPO3\CMS\Backend\Toolbar\ClearCacheActionsHookInterface;
+use TYPO3\CMS\Backend\Toolbar\ToolbarItemInterface;
+use TYPO3\CMS\Core\Authentication\BackendUserAuthentication;
+use TYPO3\CMS\Core\Page\PageRenderer;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Fluid\View\StandaloneView;
+
+/**
+ * Render cache clearing toolbar item
+ * Adds a dropdown if there are more than one item to clear (usually for admins to render the flush all caches)
+ *
+ * The dropdown items can be extended via a hook named "cacheActions".
+ */
+class ClearCacheToolbarItem implements ToolbarItemInterface
+{
+    /**
+     * @var array
+     */
+    protected $cacheActions = [];
+
+    /**
+     * @var array
+     */
+    protected $optionValues = [];
+
+    /**
+     * @throws \UnexpectedValueException
+     */
+    public function __construct()
+    {
+        $this->getPageRenderer()->loadRequireJsModule('TYPO3/CMS/Backend/Toolbar/ClearCacheMenu');
+        $isAdmin = $this->getBackendUser()->isAdmin();
+        $userTsConfig = $this->getBackendUser()->getTSConfig();
+        $uriBuilder = GeneralUtility::makeInstance(UriBuilder::class);
+
+        // Clear all page-related caches
+        if ($isAdmin || $userTsConfig['options.']['clearCache.']['pages'] ?? false) {
+            $this->cacheActions[] = [
+                'id' => 'pages',
+                'title' => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:flushPageCachesTitle',
+                'description' => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:flushPageCachesDescription',
+                'href' => (string)$uriBuilder->buildUriFromRoute('tce_db', ['cacheCmd' => 'pages']),
+                'iconIdentifier' => 'actions-system-cache-clear-impact-low'
+            ];
+            $this->optionValues[] = 'pages';
+        }
+
+        // Clearing of all caches is only shown if explicitly enabled via TSConfig
+        // or if BE-User is admin and the TSconfig explicitly disables the possibility for admins.
+        // This is useful for big production systems where admins accidentally could slow down the system.
+        if (($userTsConfig['options.']['clearCache.']['all'] ?? false)
+            || ($isAdmin && (bool)($userTsConfig['options.']['clearCache.']['all'] ?? true))
+        ) {
+            $this->cacheActions[] = [
+                'id' => 'all',
+                'title' => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:flushAllCachesTitle2',
+                'description' => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:flushAllCachesDescription2',
+                'href' => (string)$uriBuilder->buildUriFromRoute('tce_db', ['cacheCmd' => 'all']),
+                'iconIdentifier' => 'actions-system-cache-clear-impact-high'
+            ];
+            $this->optionValues[] = 'all';
+        }
+
+        // Hook for manipulating cacheActions
+        foreach ($GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['additionalBackendItems']['cacheActions'] ?? [] as $cacheAction) {
+            $hookObject = GeneralUtility::makeInstance($cacheAction);
+            if (!$hookObject instanceof ClearCacheActionsHookInterface) {
+                throw new \UnexpectedValueException($cacheAction . ' must implement interface ' . ClearCacheActionsHookInterface::class, 1228262000);
+            }
+            $hookObject->manipulateCacheActions($this->cacheActions, $this->optionValues);
+        }
+    }
+
+    /**
+     * Checks whether the user has access to this toolbar item
+     *
+     * @return bool TRUE if user has access, FALSE if not
+     */
+    public function checkAccess()
+    {
+        $backendUser = $this->getBackendUser();
+        if ($backendUser->isAdmin()) {
+            return true;
+        }
+        foreach ($this->optionValues as $value) {
+            if ($backendUser->getTSConfig()['options.']['clearCache.'][$value] ?? false) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Render clear cache icon, based on the option if there is more than one icon or just one.
+     *
+     * @return string Icon HTML
+     */
+    public function getItem()
+    {
+        if ($this->hasDropDown()) {
+            return $this->getFluidTemplateObject('ClearCacheToolbarItem.html')->render();
+        }
+        $view = $this->getFluidTemplateObject('ClearCacheToolbarItemSingle.html');
+        $cacheAction = end($this->cacheActions);
+        $view->assignMultiple([
+                'link'  => $cacheAction['href'],
+                'title' => $cacheAction['title'],
+                'iconIdentifier'  => $cacheAction['iconIdentifier'],
+            ]);
+        return $view->render();
+    }
+
+    /**
+     * Render drop down
+     *
+     * @return string Drop down HTML
+     */
+    public function getDropDown()
+    {
+        $view = $this->getFluidTemplateObject('ClearCacheToolbarItemDropDown.html');
+        $view->assign('cacheActions', $this->cacheActions);
+        return $view->render();
+    }
+
+    /**
+     * No additional attributes needed.
+     *
+     * @return array
+     */
+    public function getAdditionalAttributes()
+    {
+        return [];
+    }
+
+    /**
+     * This item has a drop down if there is more than one cache action available for the current Backend user.
+     *
+     * @return bool
+     */
+    public function hasDropDown()
+    {
+        return count($this->cacheActions) > 1;
+    }
+
+    /**
+     * Position relative to others
+     *
+     * @return int
+     */
+    public function getIndex()
+    {
+        return 25;
+    }
+
+    /**
+     * Returns the current BE user.
+     *
+     * @return BackendUserAuthentication
+     */
+    protected function getBackendUser()
+    {
+        return $GLOBALS['BE_USER'];
+    }
+
+    /**
+     * @return PageRenderer
+     */
+    protected function getPageRenderer()
+    {
+        return GeneralUtility::makeInstance(PageRenderer::class);
+    }
+
+    /**
+     * Returns a new standalone view, shorthand function
+     *
+     * @param string $filename Which templateFile should be used.
+     * @return StandaloneView
+     */
+    protected function getFluidTemplateObject(string $filename): StandaloneView
+    {
+        $view = GeneralUtility::makeInstance(StandaloneView::class);
+        $view->setLayoutRootPaths(['EXT:backend/Resources/Private/Layouts']);
+        $view->setPartialRootPaths(['EXT:backend/Resources/Private/Partials/ToolbarItems']);
+        $view->setTemplateRootPaths(['EXT:backend/Resources/Private/Templates/ToolbarItems']);
+
+        $view->setTemplate($filename);
+
+        $view->getRequest()->setControllerExtensionName('Backend');
+        return $view;
+    }
+}

typo3/sysext/backend/Classes/Backend/ToolbarItems/HelpToolbarItem.php

@@ -0,0 +1,124 @@
+<?php
+namespace TYPO3\CMS\Backend\Backend\ToolbarItems;
+
+/*
+ * 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!
+ */
+
+use TYPO3\CMS\Backend\Domain\Model\Module\BackendModule;
+use TYPO3\CMS\Backend\Domain\Repository\Module\BackendModuleRepository;
+use TYPO3\CMS\Backend\Toolbar\ToolbarItemInterface;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Fluid\View\StandaloneView;
+
+/**
+ * Help toolbar item
+ */
+class HelpToolbarItem implements ToolbarItemInterface
+{
+    /**
+     * @var BackendModule
+     */
+    protected $helpModuleMenu;
+
+    /**
+     * Constructor
+     */
+    public function __construct()
+    {
+        $backendModuleRepository = GeneralUtility::makeInstance(BackendModuleRepository::class);
+        $helpModuleMenu = $backendModuleRepository->findByModuleName('help');
+        if ($helpModuleMenu && $helpModuleMenu->getChildren()->count() > 0) {
+            $this->helpModuleMenu = $helpModuleMenu;
+        }
+    }
+
+    /**
+     * Users see this if a module is available
+     *
+     * @return bool TRUE
+     */
+    public function checkAccess()
+    {
+        return (bool)$this->helpModuleMenu;
+    }
+
+    /**
+     * Render help icon
+     *
+     * @return string toolbar item for the help icon
+     */
+    public function getItem()
+    {
+        return $this->getFluidTemplateObject('HelpToolbarItem.html')->render();
+    }
+
+    /**
+     * Render drop down
+     *
+     * @return string
+     */
+    public function getDropDown()
+    {
+        $view = $this->getFluidTemplateObject('HelpToolbarItemDropDown.html');
+        $view->assign('modules', $this->helpModuleMenu->getChildren());
+        return $view->render();
+    }
+
+    /**
+     * No additional attributes needed.
+     *
+     * @return array
+     */
+    public function getAdditionalAttributes()
+    {
+        return [];
+    }
+
+    /**
+     * This item has a drop down
+     *
+     * @return bool
+     */
+    public function hasDropDown()
+    {
+        return true;
+    }
+
+    /**
+     * Position relative to others
+     *
+     * @return int
+     */
+    public function getIndex()
+    {
+        return 70;
+    }
+
+    /**
+     * Returns a new standalone view, shorthand function
+     *
+     * @param string $filename Which templateFile should be used.
+     * @return StandaloneView
+     */
+    protected function getFluidTemplateObject(string $filename): StandaloneView
+    {
+        $view = GeneralUtility::makeInstance(StandaloneView::class);
+        $view->setLayoutRootPaths(['EXT:backend/Resources/Private/Layouts']);
+        $view->setPartialRootPaths(['EXT:backend/Resources/Private/Partials/ToolbarItems']);
+        $view->setTemplateRootPaths(['EXT:backend/Resources/Private/Templates/ToolbarItems']);
+        $view->setTemplate($filename);
+
+        $view->getRequest()->setControllerExtensionName('Backend');
+        return $view;
+    }
+}

typo3/sysext/backend/Classes/Backend/ToolbarItems/LiveSearchToolbarItem.php

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+<?php
+namespace TYPO3\CMS\Backend\Backend\ToolbarItems;
+
+/*
+ * 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!
+ */
+
+use TYPO3\CMS\Backend\Domain\Repository\Module\BackendModuleRepository;
+use TYPO3\CMS\Backend\Toolbar\ToolbarItemInterface;
+use TYPO3\CMS\Core\Page\PageRenderer;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Fluid\View\StandaloneView;
+
+/**
+ * Adds backend live search to the toolbar by adding JavaScript and adding an input search field
+ */
+class LiveSearchToolbarItem implements ToolbarItemInterface
+{
+    /**
+     * Loads the needed JavaScript file, ands includes it to the page renderer
+     */
+    public function __construct()
+    {
+        $this->getPageRenderer()->loadRequireJsModule('TYPO3/CMS/Backend/LiveSearch');
+    }
+
+    /**
+     * Checks whether the user has access to this toolbar item,
+     * only allowed when the list module is available.
+     * Live search is heavily dependent on the list module and only available when that module is.
+     *
+     * @return bool TRUE if user has access, FALSE if not
+     */
+    public function checkAccess()
+    {
+        $backendModuleRepository = GeneralUtility::makeInstance(BackendModuleRepository::class);
+        $listModule = $backendModuleRepository->findByModuleName('web_list');
+        return $listModule !== null && $listModule !== false;
+    }
+
+    /**
+     * Render search field
+     *
+     * @return string Live search form HTML
+     */
+    public function getItem()
+    {
+        return $this->getFluidTemplateObject('LiveSearchToolbarItem.html')->render();
+    }
+
+    /**
+     * This item needs to additional attributes
+     *
+     * @return array
+     */
+    public function getAdditionalAttributes()
+    {
+        return ['class' => 'toolbar-item-search t3js-toolbar-item-search'];
+    }
+
+    /**
+     * This item has no drop down
+     *
+     * @return bool
+     */
+    public function hasDropDown()
+    {
+        return false;
+    }
+
+    /**
+     * No drop down here
+     *
+     * @return string
+     */
+    public function getDropDown()
+    {
+        return '';
+    }
+
+    /**
+     * Position relative to others, live search should be very right
+     *
+     * @return int
+     */
+    public function getIndex()
+    {
+        return 90;
+    }
+
+    /**
+     * Returns current PageRenderer
+     *
+     * @return PageRenderer
+     */
+    protected function getPageRenderer()
+    {
+        return GeneralUtility::makeInstance(PageRenderer::class);
+    }
+
+    /**
+     * Returns a new standalone view, shorthand function
+     *
+     * @param string $filename Which templateFile should be used.
+     * @return StandaloneView
+     */
+    protected function getFluidTemplateObject(string $filename): StandaloneView
+    {
+        $view = GeneralUtility::makeInstance(StandaloneView::class);
+        $view->setLayoutRootPaths(['EXT:backend/Resources/Private/Layouts']);
+        $view->setPartialRootPaths(['EXT:backend/Resources/Private/Partials/ToolbarItems']);
+        $view->setTemplateRootPaths(['EXT:backend/Resources/Private/Templates/ToolbarItems']);
+
+        $view->setTemplate($filename);
+
+        $view->getRequest()->setControllerExtensionName('Backend');
+        return $view;
+    }
+}

typo3/sysext/backend/Classes/Backend/ToolbarItems/ShortcutToolbarItem.php

@@ -0,0 +1,170 @@
+<?php
+namespace TYPO3\CMS\Backend\Backend\ToolbarItems;
+
+/*
+ * 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!
+ */
+
+use TYPO3\CMS\Backend\Backend\Shortcut\ShortcutRepository;
+use TYPO3\CMS\Backend\Toolbar\ToolbarItemInterface;
+use TYPO3\CMS\Core\Page\PageRenderer;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Fluid\View\StandaloneView;
+
+/**
+ * Class to render the shortcut menu
+ *
+ * @internal This class is a specific Backend implementation and is not considered part of the Public TYPO3 API.
+ */
+class ShortcutToolbarItem implements ToolbarItemInterface
+{
+    /**
+     * @var ShortcutRepository
+     */
+    protected $shortcutRepository;
+
+    /**
+     * Constructor
+     */
+    public function __construct()
+    {
+        $this->shortcutRepository = GeneralUtility::makeInstance(ShortcutRepository::class);
+
+        $pageRenderer = GeneralUtility::makeInstance(PageRenderer::class);
+        $pageRenderer->loadRequireJsModule('TYPO3/CMS/Backend/Toolbar/ShortcutMenu');
+        $languageService = $this->getLanguageService();
+        $languageFile = 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf';
+        $pageRenderer->addInlineLanguageLabelArray([
+            'bookmark.delete' => $languageService->sL($languageFile . ':toolbarItems.bookmarksDelete'),
+            'bookmark.confirmDelete' => $languageService->sL($languageFile . ':toolbarItems.confirmBookmarksDelete'),
+            'bookmark.create' => $languageService->sL($languageFile . ':toolbarItems.createBookmark'),
+            'bookmark.savedTitle' => $languageService->sL($languageFile . ':toolbarItems.bookmarkSavedTitle'),
+            'bookmark.savedMessage' => $languageService->sL($languageFile . ':toolbarItems.bookmarkSavedMessage'),
+        ]);
+    }
+
+    /**
+     * Checks whether the user has access to this toolbar item
+     *
+     * @return bool TRUE if user has access, FALSE if not
+     */
+    public function checkAccess()
+    {
+        return (bool)($this->getBackendUser()->getTSConfig()['options.']['enableBookmarks'] ?? false);
+    }
+
+    /**
+     * Render shortcut icon
+     *
+     * @return string HTML
+     * @throws \TYPO3\CMS\Extbase\Mvc\Exception\InvalidExtensionNameException
+     * @throws \InvalidArgumentException
+     */
+    public function getItem()
+    {
+        return $this->getFluidTemplateObject('Item.html')->render();
+    }
+
+    /**
+     * This item has a drop down
+     *
+     * @return bool
+     */
+    public function hasDropDown()
+    {
+        return true;
+    }
+
+    /**
+     * Render drop down content
+     *
+     * @return string HTML
+     */
+    public function getDropDown()
+    {
+        $shortcutMenu = [];
+        $groups = $this->shortcutRepository->getGroupsFromShortcuts();
+        arsort($groups, SORT_NUMERIC);
+
+        foreach ($groups as $groupId => $groupLabel) {
+            $shortcutMenu[] = [
+                'id' => (int)$groupId,
+                'title' => $groupLabel,
+                'shortcuts' => $this->shortcutRepository->getShortcutsByGroup($groupId),
+            ];
+        }
+
+        $dropDownView = $this->getFluidTemplateObject('DropDown.html');
+        $dropDownView->assign('shortcutMenu', $shortcutMenu);
+
+        return $dropDownView->render();
+    }
+
+    /**
+     * This toolbar item needs no additional attributes
+     *
+     * @return array
+     */
+    public function getAdditionalAttributes()
+    {
+        return [];
+    }
+
+    /**
+     * Position relative to others, live search should be very right
+     *
+     * @return int
+     */
+    public function getIndex()
+    {
+        return 20;
+    }
+
+    /**
+     * returns a new standalone view, shorthand function
+     *
+     * @param string $templateFilename
+     * @return StandaloneView
+     * @throws \TYPO3\CMS\Extbase\Mvc\Exception\InvalidExtensionNameException
+     * @throws \InvalidArgumentException
+     * @internal param string $templateFile
+     */
+    protected function getFluidTemplateObject(string $templateFilename): StandaloneView
+    {
+        $view = GeneralUtility::makeInstance(StandaloneView::class);
+        $view->setLayoutRootPaths(['EXT:backend/Resources/Private/Layouts']);
+        $view->setPartialRootPaths(['EXT:backend/Resources/Private/Partials']);
+        $view->setTemplateRootPaths(['EXT:backend/Resources/Private/Templates/ShortcutToolbarItem']);
+        $view->setTemplate($templateFilename);
+        $view->getRequest()->setControllerExtensionName('Backend');
+
+        return $view;
+    }
+
+    /**
+     * Returns the current BE user.
+     *
+     * @return \TYPO3\CMS\Core\Authentication\BackendUserAuthentication
+     */
+    protected function getBackendUser()
+    {
+        return $GLOBALS['BE_USER'];
+    }
+
+    /**
+     * @return \TYPO3\CMS\Core\Localization\LanguageService
+     */
+    protected function getLanguageService()
+    {
+        return $GLOBALS['LANG'];
+    }
+}

typo3/sysext/backend/Classes/Backend/ToolbarItems/SystemInformationToolbarItem.php

@@ -0,0 +1,440 @@
+<?php
+namespace TYPO3\CMS\Backend\Backend\ToolbarItems;
+
+/*
+ * 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!
+ */
+
+use TYPO3\CMS\Backend\Routing\UriBuilder;
+use TYPO3\CMS\Backend\Toolbar\Enumeration\InformationStatus;
+use TYPO3\CMS\Backend\Toolbar\ToolbarItemInterface;
+use TYPO3\CMS\Core\Core\Environment;
+use TYPO3\CMS\Core\Core\SystemEnvironmentBuilder;
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Page\PageRenderer;
+use TYPO3\CMS\Core\Routing\RouteNotFoundException;
+use TYPO3\CMS\Core\Utility\CommandUtility;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Core\Utility\StringUtility;
+use TYPO3\CMS\Core\Utility\VersionNumberUtility;
+use TYPO3\CMS\Extbase\Object\ObjectManager;
+use TYPO3\CMS\Extbase\SignalSlot\Dispatcher;
+use TYPO3\CMS\Fluid\View\StandaloneView;
+
+/**
+ * Render system info toolbar item
+ */
+class SystemInformationToolbarItem implements ToolbarItemInterface
+{
+    /**
+     * Number displayed as badge on the dropdown trigger
+     *
+     * @var int
+     */
+    protected $totalCount = 0;
+
+    /**
+     * Holds the highest severity
+     *
+     * @var InformationStatus
+     */
+    protected $highestSeverity;
+
+    /**
+     * The CSS class for the badge
+     *
+     * @var string
+     */
+    protected $severityBadgeClass = '';
+
+    /**
+     * @var array
+     */
+    protected $systemInformation = [];
+
+    /**
+     * @var array
+     */
+    protected $systemMessages = [];
+
+    /**
+     * @var Dispatcher
+     */
+    protected $signalSlotDispatcher;
+
+    /**
+     * @var int
+     */
+    protected $maximumCountInBadge = 99;
+
+    /**
+     * Constructor
+     */
+    public function __construct()
+    {
+        $this->getPageRenderer()->loadRequireJsModule('TYPO3/CMS/Backend/Toolbar/SystemInformationMenu');
+        $this->highestSeverity = InformationStatus::cast(InformationStatus::STATUS_INFO);
+    }
+
+    /**
+     * Add a system message.
+     * This is a callback method for signal receivers.
+     *
+     * @param string $text The text to be displayed
+     * @param string $status The status of this system message
+     * @param int $count Will be added to the total count
+     * @param string $module The associated module
+     * @param string $params Query string with additional parameters
+     */
+    public function addSystemMessage($text, $status = InformationStatus::STATUS_OK, $count = 0, $module = '', $params = '')
+    {
+        $this->totalCount += (int)$count;
+
+        /** @var InformationStatus $messageSeverity */
+        $messageSeverity = InformationStatus::cast($status);
+        // define the severity for the badge
+        if ($messageSeverity->isGreaterThan($this->highestSeverity)) {
+            $this->highestSeverity = $messageSeverity;
+        }
+
+        $this->systemMessages[] = [
+            'module' => $module,
+            'params' => $params,
+            'count' => (int)$count,
+            'status' => $messageSeverity,
+            'text' => $text
+        ];
+    }
+
+    /**
+     * Add a system information.
+     * This is a callback method for signal receivers.
+     *
+     * @param string $title The title of this system information
+     * @param string $value The associated value
+     * @param string $iconIdentifier The icon identifier
+     * @param string $status The status of this system information
+     */
+    public function addSystemInformation($title, $value, $iconIdentifier, $status = InformationStatus::STATUS_NOTICE)
+    {
+        $this->systemInformation[] = [
+            'title' => $title,
+            'value' => $value,
+            'iconIdentifier' => $iconIdentifier,
+            'status' => $status
+        ];
+    }
+
+    /**
+     * Checks whether the user has access to this toolbar item
+     *
+     * @return bool TRUE if user has access, FALSE if not
+     */
+    public function checkAccess()
+    {
+        return $this->getBackendUserAuthentication()->isAdmin();
+    }
+
+    /**
+     * Render system information dropdown
+     *
+     * @return string Icon HTML
+     */
+    public function getItem()
+    {
+        return $this->getFluidTemplateObject('SystemInformationToolbarItem.html')->render();
+    }
+
+    /**
+     * Render drop down
+     *
+     * @return string Drop down HTML
+     */
+    public function getDropDown()
+    {
+        if (!$this->checkAccess()) {
+            return '';
+        }
+
+        $this->collectInformation();
+
+        $uriBuilder = GeneralUtility::makeInstance(UriBuilder::class);
+        $view = $this->getFluidTemplateObject('SystemInformationDropDown.html');
+
+        try {
+            $environmentToolUrl = (string)$uriBuilder->buildUriFromRoute('tools_toolsenvironment');
+        } catch (RouteNotFoundException $e) {
+            $environmentToolUrl = '';
+        }
+
+        $view->assignMultiple([
+            'environmentToolUrl' => $environmentToolUrl,
+            'messages' => $this->systemMessages,
+            'count' => $this->totalCount > $this->maximumCountInBadge ? $this->maximumCountInBadge . '+' : $this->totalCount,
+            'severityBadgeClass' => $this->severityBadgeClass,
+            'systemInformation' => $this->systemInformation
+        ]);
+        return $view->render();
+    }
+
+    /**
+     * No additional attributes needed.
+     *
+     * @return array
+     */
+    public function getAdditionalAttributes()
+    {
+        return [];
+    }
+
+    /**
+     * This item has a drop down
+     *
+     * @return bool
+     */
+    public function hasDropDown()
+    {
+        return true;
+    }
+
+    /**
+     * Position relative to others
+     *
+     * @return int
+     */
+    public function getIndex()
+    {
+        return 75;
+    }
+
+    /**
+     * Collect the information for the menu
+     */
+    protected function collectInformation()
+    {
+        $this->getTypo3Version();
+        $this->getWebServer();
+        $this->getPhpVersion();
+        $this->getDatabase();
+        $this->getApplicationContext();
+        $this->getComposerMode();
+        $this->getGitRevision();
+        $this->getOperatingSystem();
+
+        $this->emitGetSystemInformation();
+        $this->emitLoadMessages();
+
+        $this->severityBadgeClass = !$this->highestSeverity->equals(InformationStatus::STATUS_NOTICE) ? 'badge-' . (string)$this->highestSeverity : '';
+    }
+
+    /**
+     * Gets the TYPO3 version
+     */
+    protected function getTypo3Version()
+    {
+        $this->systemInformation[] = [
+            'title' => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:toolbarItems.sysinfo.typo3-version',
+            'value' => VersionNumberUtility::getCurrentTypo3Version(),
+            'iconIdentifier' => 'information-typo3-version'
+        ];
+    }
+
+    /**
+     * Gets the webserver software
+     */
+    protected function getWebServer()
+    {
+        $this->systemInformation[] = [
+            'title' => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:toolbarItems.sysinfo.webserver',
+            'value' => $_SERVER['SERVER_SOFTWARE'],
+            'iconIdentifier' => 'information-webserver'
+        ];
+    }
+
+    /**
+     * Gets the PHP version
+     */
+    protected function getPhpVersion()
+    {
+        $this->systemInformation[] = [
+            'title' => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:toolbarItems.sysinfo.phpversion',
+            'value' => PHP_VERSION,
+            'iconIdentifier' => 'information-php-version'
+        ];
+    }
+
+    /**
+     * Get the database info
+     */
+    protected function getDatabase()
+    {
+        foreach (GeneralUtility::makeInstance(ConnectionPool::class)->getConnectionNames() as $connectionName) {
+            $this->systemInformation[] = [
+                'title' => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:toolbarItems.sysinfo.database',
+                'titleAddition' => $connectionName,
+                'value' => GeneralUtility::makeInstance(ConnectionPool::class)
+                    ->getConnectionByName($connectionName)
+                    ->getServerVersion(),
+                'iconIdentifier' => 'information-database'
+            ];
+        }
+    }
+
+    /**
+     * Gets the application context
+     */
+    protected function getApplicationContext()
+    {
+        $applicationContext = GeneralUtility::getApplicationContext();
+        $this->systemInformation[] = [
+            'title'  => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:toolbarItems.sysinfo.applicationcontext',
+            'value'  => (string)$applicationContext,
+            'status' => $applicationContext->isProduction() ? InformationStatus::STATUS_OK : InformationStatus::STATUS_WARNING,
+            'iconIdentifier' => 'information-application-context'
+        ];
+    }
+
+    /**
+     * Adds the information if the Composer mode is enabled or disabled to the displayed system information
+     */
+    protected function getComposerMode()
+    {
+        if (!Environment::isComposerMode()) {
+            return;
+        }
+
+        $this->systemInformation[] = [
+            'title' => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:toolbarItems.sysinfo.composerMode',
+            'value' => $GLOBALS['LANG']->sL('LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:labels.enabled'),
+            'iconIdentifier' => 'information-composer-mode'
+        ];
+    }
+
+    /**
+     * Gets the current GIT revision and branch
+     */
+    protected function getGitRevision()
+    {
+        if (!StringUtility::endsWith(TYPO3_version, '-dev') || SystemEnvironmentBuilder::isFunctionDisabled('exec')) {
+            return;
+        }
+        // check if git exists
+        CommandUtility::exec('git --version', $_, $returnCode);
+        if ((int)$returnCode !== 0) {
+            // git is not available
+            return;
+        }
+
+        $revision = trim(CommandUtility::exec('git rev-parse --short HEAD'));
+        $branch = trim(CommandUtility::exec('git rev-parse --abbrev-ref HEAD'));
+        if (!empty($revision) && !empty($branch)) {
+            $this->systemInformation[] = [
+                'title' => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:toolbarItems.sysinfo.gitrevision',
+                'value' => sprintf('%s [%s]', $revision, $branch),
+                'iconIdentifier' => 'information-git'
+            ];
+        }
+    }
+
+    /**
+     * Gets the system kernel and version
+     */
+    protected function getOperatingSystem()
+    {
+        switch (PHP_OS_FAMILY) {
+            case 'Linux':
+                $icon = 'linux';
+                break;
+            case 'Darwin':
+                $icon = 'apple';
+                break;
+            case 'Windows':
+                $icon = 'windows';
+                break;
+            default:
+                $icon = 'unknown';
+        }
+        $this->systemInformation[] = [
+            'title' => 'LLL:EXT:core/Resources/Private/Language/locallang_core.xlf:toolbarItems.sysinfo.operatingsystem',
+            'value' => PHP_OS . ' ' . php_uname('r'),
+            'iconIdentifier' => 'information-os-' . $icon
+        ];
+    }
+
+    /**
+     * Emits the "getSystemInformation" signal
+     */
+    protected function emitGetSystemInformation()
+    {
+        $this->getSignalSlotDispatcher()->dispatch(__CLASS__, 'getSystemInformation', [$this]);
+    }
+
+    /**
+     * Emits the "loadMessages" signal
+     */
+    protected function emitLoadMessages()
+    {
+        $this->getSignalSlotDispatcher()->dispatch(__CLASS__, 'loadMessages', [$this]);
+    }
+
+    /**
+     * Returns a new standalone view, shorthand function
+     *
+     * @param string $filename Which templateFile should be used.
+     * @return StandaloneView
+     */
+    protected function getFluidTemplateObject(string $filename): StandaloneView
+    {
+        $view = GeneralUtility::makeInstance(StandaloneView::class);
+        $view->setLayoutRootPaths(['EXT:backend/Resources/Private/Layouts']);
+        $view->setPartialRootPaths(['EXT:backend/Resources/Private/Partials/ToolbarItems']);
+        $view->setTemplateRootPaths(['EXT:backend/Resources/Private/Templates/ToolbarItems']);
+
+        $view->setTemplate($filename);
+
+        $view->getRequest()->setControllerExtensionName('Backend');
+        return $view;
+    }
+
+    /**
+     * Returns the current BE user.
+     *
+     * @return \TYPO3\CMS\Core\Authentication\BackendUserAuthentication
+     */
+    protected function getBackendUserAuthentication()
+    {
+        return $GLOBALS['BE_USER'];
+    }
+
+    /**
+     * Returns current PageRenderer
+     *
+     * @return PageRenderer
+     */
+    protected function getPageRenderer()
+    {
+        return GeneralUtility::makeInstance(PageRenderer::class);
+    }
+
+    /**
+     * Get the SignalSlot dispatcher
+     *
+     * @return Dispatcher
+     */
+    protected function getSignalSlotDispatcher()
+    {
+        if (!isset($this->signalSlotDispatcher)) {
+            $this->signalSlotDispatcher = GeneralUtility::makeInstance(ObjectManager::class)->get(Dispatcher::class);
+        }
+        return $this->signalSlotDispatcher;
+    }
+}

typo3/sysext/backend/Classes/Backend/ToolbarItems/UserToolbarItem.php

@@ -0,0 +1,188 @@
+<?php
+namespace TYPO3\CMS\Backend\Backend\ToolbarItems;
+
+/*
+ * 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!
+ */
+
+use TYPO3\CMS\Backend\Domain\Repository\Module\BackendModuleRepository;
+use TYPO3\CMS\Backend\Routing\UriBuilder;
+use TYPO3\CMS\Backend\Toolbar\ToolbarItemInterface;
+use TYPO3\CMS\Core\Database\Connection;
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Utility\ExtensionManagementUtility;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Fluid\View\StandaloneView;
+
+/**
+ * User toolbar item
+ *
+ * @internal This class is a specific Backend implementation and is not considered part of the Public TYPO3 API.
+ */
+class UserToolbarItem implements ToolbarItemInterface
+{
+    /**
+     * Item is always enabled
+     *
+     * @return bool TRUE
+     */
+    public function checkAccess()
+    {
+        return true;
+    }
+
+    /**
+     * Render username and an icon
+     *
+     * @return string HTML
+     */
+    public function getItem()
+    {
+        $backendUser = $this->getBackendUser();
+        $view = $this->getFluidTemplateObject('UserToolbarItem.html');
+        $view->assignMultiple([
+            'currentUser' => $backendUser->user,
+            'switchUserMode' => $backendUser->user['ses_backuserid'],
+        ]);
+        return $view->render();
+    }
+
+    /**
+     * Render drop down
+     *
+     * @return string HTML
+     */
+    public function getDropDown()
+    {
+        $backendUser = $this->getBackendUser();
+
+        /** @var BackendModuleRepository $backendModuleRepository */
+        $backendModuleRepository = GeneralUtility::makeInstance(BackendModuleRepository::class);
+        $uriBuilder = GeneralUtility::makeInstance(UriBuilder::class);
+
+        $mostRecentUsers = [];
+        if (ExtensionManagementUtility::isLoaded('beuser')
+            && $backendUser->isAdmin()
+            && (int)$backendUser->user['ses_backuserid'] === 0
+            && isset($backendUser->uc['recentSwitchedToUsers'])
+            && is_array($backendUser->uc['recentSwitchedToUsers'])
+        ) {
+            $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable('be_users');
+            $result = $queryBuilder
+                ->select('uid', 'username', 'realName')
+                ->from('be_users')
+                ->where(
+                    $queryBuilder->expr()->in('uid', $queryBuilder->createNamedParameter($backendUser->uc['recentSwitchedToUsers'], Connection::PARAM_INT_ARRAY))
+                )->execute();
+
+            // Flip the array to have a "sorted" list of items
+            $mostRecentUsers = array_flip($backendUser->uc['recentSwitchedToUsers']);
+
+            while ($row = $result->fetch()) {
+                $row['switchUserLink'] = (string)$uriBuilder->buildUriFromRoute(
+                    'system_BeuserTxBeuser',
+                    [
+                        'SwitchUser' => $row['uid']
+                    ]
+                );
+
+                $mostRecentUsers[$row['uid']] = $row;
+            }
+
+            // Remove any item that is not an array (means, the stored uid is not available anymore)
+            $mostRecentUsers = array_filter($mostRecentUsers, function ($record) {
+                return is_array($record);
+            });
+
+            $availableUsers = array_keys($mostRecentUsers);
+            if (!empty(array_diff($backendUser->uc['recentSwitchedToUsers'], $availableUsers))) {
+                $backendUser->uc['recentSwitchedToUsers'] = $availableUsers;
+                $backendUser->writeUC();
+            }
+        }
+
+        $view = $this->getFluidTemplateObject('UserToolbarItemDropDown.html');
+        $view->assignMultiple([
+            'modules' => $backendModuleRepository->findByModuleName('user')->getChildren(),
+            'logoutUrl' => (string)$uriBuilder->buildUriFromRoute('logout'),
+            'switchUserMode' => $this->getBackendUser()->user['ses_backuserid'],
+            'recentUsers' => $mostRecentUsers,
+        ]);
+        return $view->render();
+    }
+
+    /**
+     * Returns an additional class if user is in "switch user" mode
+     *
+     * @return array
+     */
+    public function getAdditionalAttributes()
+    {
+        $result = [
+            'class' => 'toolbar-item-user'
+        ];
+        if ($this->getBackendUser()->user['ses_backuserid']) {
+            $result['class'] .= ' su-user';
+        }
+        return $result;
+    }
+
+    /**
+     * This item has a drop down
+     *
+     * @return bool
+     */
+    public function hasDropDown()
+    {
+        return true;
+    }
+
+    /**
+     * Position relative to others
+     *
+     * @return int
+     */
+    public function getIndex()
+    {
+        return 80;
+    }
+
+    /**
+     * Returns the current BE user.
+     *
+     * @return \TYPO3\CMS\Core\Authentication\BackendUserAuthentication
+     */
+    protected function getBackendUser()
+    {
+        return $GLOBALS['BE_USER'];
+    }
+
+    /**
+     * Returns a new standalone view, shorthand function
+     *
+     * @param string $filename Which templateFile should be used.
+     *
+     * @return StandaloneView
+     */
+    protected function getFluidTemplateObject(string $filename): StandaloneView
+    {
+        $view = GeneralUtility::makeInstance(StandaloneView::class);
+        $view->setLayoutRootPaths(['EXT:backend/Resources/Private/Layouts']);
+        $view->setPartialRootPaths(['EXT:backend/Resources/Private/Partials/ToolbarItems']);
+        $view->setTemplateRootPaths(['EXT:backend/Resources/Private/Templates/ToolbarItems']);
+
+        $view->setTemplate($filename);
+
+        $view->getRequest()->setControllerExtensionName('Backend');
+        return $view;
+    }
+}