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TYPO3 Explained
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TYPO3 Explained

  • Introduction
  • API A-Z
    • Assets
    • Authentication
      • CSRF-like request token handling
      • Multi-factor authentication
    • Autoloading
      • ComposerClassLoader
    • Backend APIs
      • Access control
        • Users and groups
        • Password reset functionality
        • Roles
        • Options
        • Other Options
        • File mounts
        • Backend users module
      • Backend modules API
        • Modules.php
          • 3rd level
          • Toplevel
        • Backend GUI
        • DocHeaderComponent
        • ModuleData
        • ModuleInterface
        • ModuleProvider
        • ModuleTemplate
        • ModuleTemplateFactory
        • TypoScript
        • Sudo mode
      • JavaScript
        • ES6 in the TYPO3 Backend
        • RequireJS (Deprecated)
          • Use RequireJS in your own extension
          • Dependency handling
          • Loading your own or other RequireJS modules
          • Shim Library to Use it as Own RequireJS Modules
        • Client-side templating
        • Various JavaScript modules
          • Modals
          • Multi-step wizard
          • DocumentService (jQuery.ready substitute)
          • SessionStorage wrapper
        • Ajax request
        • Event API
        • Navigation via JavaScript
        • JavaScript form helpers
      • Ajax
      • Backend layout
      • Backend routing
      • Backend user object
      • Broadcast channels
      • Button components
      • Clipboard
      • Context menus
      • Custom Permissions
      • LoginProvider
      • UriBuilder
    • Bitsets & Enumerations
      • How to use enumerations
      • How to use bitsets
    • Caching
      • Quick start for integrators
      • Configuration
      • Caching framework architecture
      • Cache frontends
      • Developer information
    • System categories
    • Commands
      • List Core commands
      • Tutorial
    • Content Elements & Plugins
      • Create a custom content element type
      • Custom data processors
      • Create plugins
      • Configure custom backend preview for content element
      • Add content elements to the Content Element Wizard
      • Best practices
    • Content Security Policy
    • Context API and aspects
    • Country API
    • Cropping images
      • General Configuration
      • Crop variants configuration per content element
    • Database
      • Introduction
      • Configuration
      • Database structure
      • Upgrade table and field definitions
      • Basic create, read, update, and delete operations (CRUD)
      • Class overview
      • ConnectionPool
      • Query builder
      • Connection
      • Expression builder
      • Restriction builder
      • Result
      • Driver middlewares
      • Various tips and tricks
    • Database records
    • DataHandler
      • Introduction
      • DataHandler basics
      • Using the DataHandler in scripts
      • The "/record/commit" route
    • Debugging
    • Dependency injection
    • Deprecation Handling
    • Environment
    • Error and exception handling
      • Configuration
      • Error Handler
      • Production exception handler
      • Debug exception handler
      • Examples
      • How to extend the error and exception handling
    • Events and hooks
      • Extending the TYPO3 Core
      • Event dispatcher (PSR-14 events)
      • Event list
        • Backend
          • AfterBackendPageRenderEvent
          • AfterFormEnginePageInitializedEvent
          • AfterHistoryRollbackFinishedEvent
          • AfterPageColumnsSelectedForLocalizationEvent
          • AfterPagePreviewUriGeneratedEvent
          • AfterPageTreeItemsPreparedEvent
          • AfterRecordSummaryForLocalizationEvent
          • BeforeFormEnginePageInitializedEvent
          • BeforeHistoryRollbackStartEvent
          • BeforeModuleCreationEvent
          • BeforePagePreviewUriGeneratedEvent
          • BeforeSearchInDatabaseRecordProviderEvent
          • CustomFileControlsEvent
          • IsContentUsedOnPageLayoutEvent
          • IsFileSelectableEvent
          • ModifyAllowedItemsEvent
          • ModifyButtonBarEvent
          • ModifyClearCacheActionsEvent
          • ModifyDatabaseQueryForContentEvent
          • ModifyDatabaseQueryForRecordListingEvent
          • ModifyEditFormUserAccessEvent
          • ModifyFileReferenceControlsEvent
          • ModifyFileReferenceEnabledControlsEvent
          • ModifyGenericBackendMessagesEvent
          • ModifyImageManipulationPreviewUrlEvent
          • ModifyInlineElementControlsEvent
          • ModifyInlineElementEnabledControlsEvent
          • ModifyLinkExplanationEvent
          • ModifyLinkHandlersEvent
          • ModifyNewContentElementWizardItemsEvent
          • ModifyPageLayoutContentEvent
          • ModifyPageLayoutOnLoginProviderSelectionEvent
          • ModifyQueryForLiveSearchEvent
          • ModifyRecordListHeaderColumnsEvent
          • ModifyRecordListRecordActionsEvent
          • ModifyRecordListTableActionsEvent
          • ModifyResultItemInLiveSearchEvent
          • PageContentPreviewRenderingEvent
          • RenderAdditionalContentToRecordListEvent
          • SwitchUserEvent
          • SystemInformationToolbarCollectorEvent
        • Core
          • Authentication
            • AfterGroupsResolvedEvent
            • AfterUserLoggedInEvent
            • AfterUserLoggedOutEvent
            • BeforeRequestTokenProcessedEvent
            • BeforeUserLogoutEvent
            • LoginAttemptFailedEvent
          • Cache
            • CacheFlushEvent
            • CacheWarmupEvent
          • Configuration
            • AfterFlexFormDataStructureIdentifierInitializedEvent
            • AfterFlexFormDataStructureParsedEvent
            • AfterTcaCompilationEvent
            • BeforeFlexFormDataStructureIdentifierInitializedEvent
            • BeforeFlexFormDataStructureParsedEvent
            • ModifyLoadedPageTsConfigEvent
            • SiteConfigurationBeforeWriteEvent
            • SiteConfigurationLoadedEvent
          • Core
            • BootCompletedEvent
          • Database
            • AlterTableDefinitionStatementsEvent
          • DataHandling
            • AppendLinkHandlerElementsEvent
            • IsTableExcludedFromReferenceIndexEvent
          • Domain
            • AfterRecordLanguageOverlayEvent
            • BeforePageLanguageOverlayEvent
            • BeforeRecordLanguageOverlayEvent
            • RecordAccessGrantedEvent
          • Html
            • BrokenLinkAnalysisEvent
          • Mail
            • AfterMailerInitializationEvent
            • AfterMailerSentMessageEvent
            • BeforeMailerSentMessageEvent
          • Package
            • AfterPackageActivationEvent
            • AfterPackageDeactivationEvent
            • BeforePackageActivationEvent
            • PackagesMayHaveChangedEvent
          • Page
            • BeforeJavaScriptsRenderingEvent
            • BeforeStylesheetsRenderingEvent
          • Password policy
            • EnrichPasswordValidationContextDataEvent
          • Resource
            • AfterDefaultUploadFolderWasResolvedEvent
            • AfterFileAddedEvent
            • AfterFileAddedToIndexEvent
            • AfterFileCommandProcessedEvent
            • AfterFileContentsSetEvent
            • AfterFileCopiedEvent
            • AfterFileCreatedEvent
            • AfterFileDeletedEvent
            • AfterFileMarkedAsMissingEvent
            • AfterFileMetaDataCreatedEvent
            • AfterFileMetaDataDeletedEvent
            • AfterFileMetaDataUpdatedEvent
            • AfterFileMovedEvent
            • AfterFileProcessingEvent
            • AfterFileRemovedFromIndexEvent
            • AfterFileRenamedEvent
            • AfterFileReplacedEvent
            • AfterFileUpdatedInIndexEvent
            • AfterFolderAddedEvent
            • AfterFolderCopiedEvent
            • AfterFolderDeletedEvent
            • AfterFolderMovedEvent
            • AfterFolderRenamedEvent
            • AfterResourceStorageInitializationEvent
            • AfterVideoPreviewFetchedEvent
            • BeforeFileAddedEvent
            • BeforeFileContentsSetEvent
            • BeforeFileCopiedEvent
            • BeforeFileCreatedEvent
            • BeforeFileDeletedEvent
            • BeforeFileMovedEvent
            • BeforeFileProcessingEvent
            • BeforeFileRenamedEvent
            • BeforeFileReplacedEvent
            • BeforeFolderAddedEvent
            • BeforeFolderCopiedEvent
            • BeforeFolderDeletedEvent
            • BeforeFolderMovedEvent
            • BeforeFolderRenamedEvent
            • BeforeResourceStorageInitializationEvent
            • EnrichFileMetaDataEvent
            • GeneratePublicUrlForResourceEvent
            • ModifyFileDumpEvent
            • ModifyIconForResourcePropertiesEvent
            • SanitizeFileNameEvent
          • Security
            • InvestigateMutationsEvent
            • PolicyMutatedEvent
          • Tree
            • ModifyTreeDataEvent
          • TypoScript
            • AfterTemplatesHaveBeenDeterminedEvent
            • EvaluateModifierFunctionEvent
        • Extbase
          • Configuration
            • BeforeFlexFormConfigurationOverrideEvent
          • Mvc
            • AfterRequestDispatchedEvent
            • BeforeActionCallEvent
          • Persistence
            • AfterObjectThawedEvent
            • EntityAddedToPersistenceEvent
            • EntityPersistedEvent
            • EntityRemovedFromPersistenceEvent
            • EntityUpdatedInPersistenceEvent
            • ModifyQueryBeforeFetchingObjectDataEvent
            • ModifyResultAfterFetchingObjectDataEvent
        • ExtensionManager
          • AfterExtensionDatabaseContentHasBeenImportedEvent
          • AfterExtensionFilesHaveBeenImportedEvent
          • AfterExtensionStaticDatabaseContentHasBeenImportedEvent
          • AvailableActionsForExtensionEvent
        • Filelist
          • ModifyEditFileFormDataEvent
          • ProcessFileListActionsEvent
        • Frontend
          • AfterCacheableContentIsGeneratedEvent
          • AfterCachedPageIsPersistedEvent
          • AfterLinkIsGeneratedEvent
          • AfterPageAndLanguageIsResolvedEvent
          • AfterPageWithRootLineIsResolvedEvent
          • BeforePageIsResolvedEvent
          • FilterMenuItemsEvent
          • ModifyCacheLifetimeForPageEvent
          • ModifyHrefLangTagsEvent
          • ModifyPageLinkConfigurationEvent
          • ModifyResolvedFrontendGroupsEvent
          • ShouldUseCachedPageDataIfAvailableEvent
        • FrontendLogin
          • BeforeRedirectEvent
          • LoginConfirmedEvent
          • LoginErrorOccurredEvent
          • LogoutConfirmedEvent
          • ModifyLoginFormViewEvent
          • PasswordChangeEvent
          • SendRecoveryEmailEvent
        • Impexp
          • BeforeImportEvent
        • Info
          • ModifyInfoModuleContentEvent
        • Install
          • ModifyLanguagePackRemoteBaseUrlEvent
          • ModifyLanguagePacksEvent
        • Linkvalidator
          • BeforeRecordIsAnalyzedEvent
          • ModifyValidatorTaskEmailEvent
        • Lowlevel
          • ModifyBlindedConfigurationOptionsEvent
        • Redirects
          • AfterAutoCreateRedirectHasBeenPersistedEvent
          • BeforeRedirectMatchDomainEvent
          • ModifyAutoCreateRedirectRecordBeforePersistingEvent
          • ModifyRedirectManagementControllerViewDataEvent
          • RedirectWasHitEvent
          • SlugRedirectChangeItemCreatedEvent
        • Seo
          • ModifyUrlForCanonicalTagEvent
        • Setup
          • AddJavaScriptModulesEvent
        • Workspaces
          • AfterCompiledCacheableDataForWorkspaceEvent
          • AfterDataGeneratedForWorkspaceEvent
          • AfterRecordPublishedEvent
          • GetVersionedDataEvent
          • ModifyVersionDifferencesEvent
          • SortVersionedDataEvent
      • Hooks
      • JavaScript Event API
        • Regular event
        • Debounce event
        • Throttle event
        • RequestAnimationFrame event
    • File abstraction
      • Basic concepts
      • Architecture
        • Overview
        • Folders
        • Database structure
        • Components
        • PSR-14 events
      • Administration
        • Permissions
        • File storages
        • Maintenance
      • Using FAL
        • Using FAL in the frontend
        • TCA definition
        • The StorageRepository class
        • Working with files, folders and file references
        • Working with collections
        • Searching for files
      • File collections
    • Feature toggle API
    • Custom file processors
    • Flash messages
      • Flash messages API
      • Flash messages in Extbase
      • Flash messages renderer
      • JavaScript-based flash messages (Notification API)
    • FlexForms
      • T3DataStructure
        • Elements
        • Sheet References
        • Parsing a Data Structure
    • Fluid
      • ViewHelper reference
      • Introduction to Fluid
      • Fluid syntax
      • Using Fluid in TYPO3
      • cObject ViewHelper
      • Property additionalAttributes
      • Developing a custom ViewHelper
    • FormEngine
      • Introduction
      • Main rendering workflow
      • Data compiling
      • Rendering
    • Form protection tool
    • Global values
      • Constants
    • Icon API
    • Link handling
      • Link handler configuration
      • LinkBrowser API
      • The LinkHandler API
        • The PageLinkHandler
        • The RecordLinkHandler
        • Implementing a custom LinkHandler
        • Events to modify link handler
      • Core link handler
      • Frontend link builder
      • LinkBrowser Tutorials
        • Browse records of a table
        • Create a custom link browser
    • Localization
      • Supported languages
      • Managing translations
      • Translation servers
        • Localization with Crowdin
          • Extension integration
          • Online translation with Crowdin
          • Workflow
          • Frequently asked questions (FAQ)
        • Custom translation servers
      • Localization API
        • LanguageService
        • LanguageServiceFactory
        • Locale
        • LocalizationUtility (Extbase)
      • XLIFF Format
      • Working with XLIFF files
    • Locking API
    • Logging
      • Quickstart
      • Logger
      • Configuration
      • The LogRecord model
      • Log writers
      • Log processors
    • Mail API
    • Message bus
    • Mount points
    • Namespaces
    • Page types
      • Types of pages
      • Redirect Headers
      • Create new Page Type
    • Pagination
    • Parsing HTML
    • Password hashing
      • Troubleshooting
    • Password policies
    • Requests
      • Bootstrapping
      • Middlewares (Request handling)
      • TYPO3 request object
      • TYPO3 request attributes
        • Application type
        • Current content object
        • Frontend controller
        • Frontend TypoScript
        • Frontend user
        • Language
        • Module
        • ModuleData
        • Nonce
        • Normalized parameters
        • Route
        • Routing
        • Site
        • Target
    • Routing
      • Introduction
      • Page based
      • For extensions
      • Extending
      • Examples
    • RTE
      • CKEditor Rich Text Editor
      • Rendering in the Frontend
      • Rich text editors in the TYPO3 backend
        • Introduction
        • Plugging in a custom RTE
      • Rich Text Editors (RTE) in the TYPO3 frontend
        • Including a Rich Text Editor (RTE) in the frontend
      • RTE Transformations
        • Introduction
        • Transformation overview
      • Historical Perspective on RTE Transformations
        • Properties and Transformations
        • RTE Transformations in Content Elements
    • SEO
      • Canonical API
      • MetaTag API
      • Page title API
      • XML sitemap
    • Services
      • Introduction
      • Using Services
        • Service precedence
        • Simple usage
        • Use with subtypes
        • Calling a chain of services
      • Configuration
        • Override service registration
        • Service configuration
        • Service type configuration
      • Developer's Guide
        • Introducing a new service type
        • Implementing a service
        • Service API
        • Services API
    • Sessions
      • User session management
      • Session storage framework
    • Site handling
      • Basics
      • Creation
      • Base variants
      • Adding Languages
      • Error handling
        • Page-based error handler
        • Fluid-based error handler
        • Writing a custom page error handler
      • Static routes
      • Environment variables
      • Usage in TypoScript + Fluid
      • Usage
      • Usage in TCA
      • Site settings
      • Console tools
      • PHP API
      • Extended configuration
    • Soft references
    • Symfony expression language
    • System Overview
    • System registry
    • TSFE
    • TYPO3 information
    • Webhooks and reactions
    • Versioning and Workspaces
    • XCLASSes
  • Administration
    • Installation
      • Classic mode installation
        • TYPO3 release integrity
      • Composer-based Installation
      • Server installations
        • Composer on the server
      • System Requirements
    • Deployment
      • Initial Deployment
      • Incremental Deployment
      • Automated deployment
      • Environments
        • Configuring environments
        • Database
        • User Uploads
      • Tools
        • Rsync
        • Deployer
        • Git and Composer
      • CI/CD Automation
      • Docker Container
    • In Production
      • Backups
      • Security
      • Logging
      • Reverse Proxy
      • OPcache
    • Admin Tools
      • Maintenance
      • Settings
      • Upgrade
      • Environment
      • Content Security Policy
      • Extensions
    • Upgrades
      • Patch/Bugfix update
      • Major upgrade
        • Pre-upgrade
        • Upgrade the Core
        • Post-upgrade
      • Upgrading extensions
      • Third-party tools
      • Classic mode upgrade
      • Applying Core patches
      • Migrate a TYPO3 project to Composer
        • Requirements
        • Migration steps
        • Migrating public web assets
        • Version control
      • Migrate content
    • Docker
      • Docker demo
      • Docker Compose demo
      • Extend an Image
      • Automate TYPO3 Setup
      • In production
        • Distribution
        • Database considerations
        • File Permissions
        • Ports
        • Reverse Proxy
    • Directory structure
      • Classic mode installation
      • Flag files
    • Version Control (Git)
    • System Settings
      • Maintenance Mode
      • Production Settings
    • Backend users
      • Adding Backend Users
      • Changing the backend language
      • Backend Privileges
      • Backend Users
      • Groups
      • Setting up User Permissions
      • Page Permissions
      • Setting up a User
    • Troubleshooting
      • TYPO3
      • System Modules
      • PHP
      • Web Server
      • Database
    • Extension management
      • Composer
      • Installing Extensions - Classic mode
    • Permissions
      • General recommendations
      • Setting up backend user groups
  • Configuration
    • Overview
    • Glossary
    • Configuration module
    • $GLOBALS
    • System configuration
      • BE - backend configuration
      • DB - Database connections
      • EXT - Extension manager configuration
      • FE - frontend configuration
      • GFX - graphics configuration
      • HTTP - tune requests
      • LOG - Logging configuration
      • MAIL settings
      • SYS - System configuration
    • TypoScript
      • Introduction
      • Syntax
      • Frontend TypoScript
      • TSconfig
      • PHP API
      • Myths and FAQ
    • User settings configuration
      • ['columns'] Section
      • ['showitem'] section
      • Extending the user settings
      • View the configuration
    • YAML
      • YAML API
      • YAML syntax
      • Services.yaml
  • Coding guidelines
    • Introduction
    • PHP architecture
      • Services
      • Static Methods, static Classes, Utility Classes
      • Traits
      • Working with exceptions
    • PHP
      • General requirements for PHP files
      • File structure
      • PHP syntax formatting
      • Using phpDoc
    • PHP Best Practice
      • Named arguments
      • Singletons
      • Handling deprecations
      • Namespaces and class names of user files
    • JavaScript
    • TypeScript
    • TypoScript
    • TSconfig
    • XLIFF
    • YAML
    • reStructuredText
  • Extension development
    • The concept of TYPO3 extensions
    • File structure
      • composer.json
      • ext_conf_template.txt
      • ext_emconf.php
      • ext_localconf.php
      • ext_tables.php
      • ext_tables.sql
      • ext_tables_static+adt.sql
      • ext_typoscript_constants.typoscript
      • ext_typoscript_setup.typoscript
      • Classes
      • Configuration
        • Backend
        • Extbase
          • Persistence
        • TCA
        • TsConfig
        • TypoScript
        • ContentSecurityPolicies.php
        • Icons.php
        • page.tsconfig
        • RequestMiddlewares.php
        • Services.yaml
        • user.tsconfig
      • Documentation
      • Resources
        • Private
          • Language
        • Public
      • Tests
    • Site package
      • Introduction
    • Howto
      • Backend modules
        • Modules.php
        • Plain controller
        • Extbase controller
        • Security Considerations
        • Tutorials
      • Events
      • Model extensions
      • TCA extension
        • Storing the changes
        • Customization Examples
        • Verifying the TCA
      • Frontend plugin
      • Localization
        • Multi-language Fluid templates
        • Localization in PHP
        • TypoScript
      • Publishing
        • Publish your extension in the TER
      • External HTTP requests
      • Update
        • Extension scanner
        • Upgrade wizards
          • Concept
          • Implementation
      • Configuration
      • Distributions
      • Kickstart
      • Extension repositories
      • Documentation
    • Extbase
      • Introduction
      • Reference
        • Domain
          • Extbase model - extending AbstractEntity
            • Persistence
            • Relations
            • Hydrating
            • Localization
          • Repository
        • Controller
          • ActionController
          • Error action
          • Property mapping
          • Type converters
        • View
        • URI builder (Extbase)
        • Registration of frontend plugins
        • TypoScript configuration
        • Annotations
        • Validation
          • Custom Validator
        • File upload
        • Caching
        • Localization
        • URI arguments and reserved keywords
      • Examples
    • Best practises
      • Extension Key
      • Naming
      • Configuration Files
      • Software design
      • Loading order
    • Tutorials
      • Kickstart
        • Make
          • Create a new backend controller
          • Create a new console command
      • Tea
        • Create an extension
        • Create a directory structure
        • Model: a bag of tea
        • Repository
        • Controller
      • Components
        • composer.json
        • Models
        • Persistance
      • Extbase
  • Security guidelines
    • Overview
    • Security Team
    • Versions & Updates
    • Security Threats
    • Guidelines
    • System Administrators
      • Role Definition
      • Code Integrity
      • File permissions
      • Restrict HTTP access
      • Directory indexing
      • File extension handling
      • Content security policy
      • Database access
      • Backups
      • HTTPS & encryption
      • Insecure Uploads
      • Server environment
    • Extension development
    • Integration
      • Install tool
      • Global TYPO3 configuration options
      • Security-related warnings after login
      • Reports and logs
      • Users and access privileges
      • TYPO3 extensions
      • TypoScript
      • Content elements
    • Editor security
    • Analyze & Repair
      • Detect a hacked website
      • Take the website offline
      • Analyzing a hacked site
      • Repair/restore
      • Further actions
  • Testing
    • Extension testing
    • Project testing
    • Unit tests
      • Introduction
      • Running
    • Functional tests
      • Introduction
    • Acceptance tests
    • Test Runners: Organize and execute tests
    • Testing tutorials
      • Testing enetcache
      • Acceptance testing of site_introduction
  • About This Manual
  • Sitemap
  1. TYPO3 Explained
  2. Extension development
  3. Best practises
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Last rendered: Jun 30, 2025 15:01

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