typo3-extbase-plugin

name

typo3-extbase-plugin

description

Build TYPO3 v13+/v14+ Extbase frontend plugins from scratch — covers all layers from ext_localconf.php plugin registration through Domain Models, Repositories, Controllers, TCA configuration, TypoScript setup, ext_tables.sql, and Services.yaml dependency injection. Use this skill when creating a new Extbase plugin, adding a new controller or action, creating a new domain model with properties (including sys_category relations, fe_users ownership, Country fields, ObjectStorage relations, FileReference images), configuring TCA for custom tables, registering plugins in tt_content, or troubleshooting Extbase persistence mapping issues. Also use when adding CRUD operations (list, show, new, create, edit, update, delete) to a controller or integrating frontend user access control.

TYPO3 Extbase Plugin

Complete workflow for building Extbase frontend plugins in a TYPO3 v13+/v14+ site package.

Quick Reference — File Touchpoints

Every Extbase plugin touches these files. Work through them in this order to avoid forward-reference errors:

#	File	Purpose
1	ext_tables.sql	DB schema for custom tables
2	Configuration/TCA/tx_<ext>_domain_model_<model>.php	Backend form config per model
3	Classes/Domain/Model/<Model>.php	PHP domain model
4	Classes/Domain/Repository/<Model>Repository.php	Repository class
5	Configuration/Extbase/Persistence/Classes.php	Persistence mapping (only for non-standard table names)
6	Classes/Controller/<Name>Controller.php	Controller with actions
7	ext_localconf.php	configurePlugin() — wire controllers + actions
8	Configuration/TCA/Overrides/30_tt_content_<plugin>.php	registerPlugin() — make it insertable
9	Configuration/Services.yaml	DI: mark controller public: true
10	Configuration/Sets/<set>/TypoScript/plugin.typoscript	View paths + settings
11	Resources/Private/Templates/<Controller>/<Action>.html	Fluid templates

Workflow

1. Database Schema (ext_tables.sql)

Define columns TYPO3 does not auto-create. Convention: tx_<extkey>_domain_model_<modelname>.

CREATE TABLE tx_mysitepackage_domain_model_example (
    uid int(11) NOT NULL auto_increment,
    pid int(11) DEFAULT '0' NOT NULL,
    PRIMARY KEY (uid),
    title varchar(255) DEFAULT '' NOT NULL,
    description text,
    -- relation counters (int, not the actual FK)
    images int(11) unsigned DEFAULT '0' NOT NULL,
    categories int(11) unsigned DEFAULT '0' NOT NULL,
    -- fe_user ownership: store uid, not object
    fe_user int(11) unsigned DEFAULT '0' NOT NULL
);

[!IMPORTANT] For ObjectStorage relations (images, categories, inline children), the DB column stores a count, not a foreign key. TYPO3 manages the MM table or foreign_field internally.

2. TCA Configuration

See references/tca-patterns.md for complete field-type examples including type => 'category', type => 'country', type => 'file', type => 'inline', and type => 'select' with foreign_table => 'fe_users'.

3. Domain Model

See references/domain-model-patterns.md for property types, ObjectStorage relations, sys_category integration, and the Category shim pattern.

4. Repository

<?php
declare(strict_types=1);
namespace Vendor\MySitePackage\Domain\Repository;

use TYPO3\CMS\Extbase\Persistence\Repository;

class ExampleRepository extends Repository
{
}

Override ENTITY_CLASSNAME only when the repository must return a mapped model class (e.g., for sys_category):

class CategoryRepository extends Repository
{
    public const ENTITY_CLASSNAME = \Vendor\MySitePackage\Domain\Model\Category::class;
}

5. Persistence Mapping (Configuration/Extbase/Persistence/Classes.php)

Only needed when a model maps to a table whose name does not follow the tx_<ext>_domain_model_<name> convention:

<?php
declare(strict_types=1);

return [
    // Map to core sys_category table
    \Vendor\MySitePackage\Domain\Model\Category::class => [
        'tableName' => 'sys_category',
    ],
    // Map fe_users to a custom model
    \Vendor\MySitePackage\Domain\Model\FrontendUser::class => [
        'tableName' => 'fe_users',
    ],
    // Property name → DB column name mapping
    \Vendor\MySitePackage\Domain\Model\Blog::class => [
        'tableName' => 'tx_blog_domain_model_blog',
        'properties' => [
            'categories' => ['fieldName' => 'category'],
        ],
    ],
];

6. Controller

See references/controller-patterns.md for the full CRUD pattern, frontend user access control via Context, CountryProvider integration, and initializeAction patterns for DateTimeConverter.

7. Plugin Registration (ext_localconf.php)

<?php
declare(strict_types=1);
defined('TYPO3') or die();

\TYPO3\CMS\Extbase\Utility\ExtensionUtility::configurePlugin(
    'MySitePackage',                // Extension name (UpperCamelCase, no vendor)
    'ExampleList',                  // Plugin name (unique within extension)
    [
        \Vendor\MySitePackage\Controller\ExampleController::class => 'list, show',
    ],
    // Non-cacheable actions (forms, writes, user-specific)
    [
        \Vendor\MySitePackage\Controller\ExampleController::class => 'show',
    ]
);

Rules:

• First arg is extension name in UpperCamelCase without vendor prefix
• Cacheable = safe to cache the output; non-cacheable = must re-render every request
• Any action that writes data (create, update, delete) or shows user-specific content must be non-cacheable

8. Backend Registration (Configuration/TCA/Overrides/30_tt_content_<plugin>.php)

<?php
declare(strict_types=1);

\TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerPlugin(
    'MySitePackage',
    'ExampleList',
    'Example List'          // Label shown in backend dropdown
);

9. Dependency Injection (Configuration/Services.yaml)

services:
  _defaults:
    autowire: true
    autoconfigure: true
    public: false

  Vendor\MySitePackage\:
    resource: '../Classes/*'

  Vendor\MySitePackage\Controller\ExampleController:
    public: true

Every controller must be registered as public: true.

10. TypoScript Plugin Setup

plugin.tx_mysitepackage {
    view {
        templateRootPaths {
            10 = EXT:my_site_package/Resources/Private/Templates/
        }
        partialRootPaths {
            10 = EXT:my_site_package/Resources/Private/Partials/
        }
        layoutRootPaths {
            10 = EXT:my_site_package/Resources/Private/Layouts/
        }
    }
    settings {
        # Custom plugin settings accessible via {settings.key} in Fluid
        storagePid = 5
    }
}

11. Fluid Templates

Template path convention: Resources/Private/Templates/<ControllerName>/<ActionName>.html

Example for list action: Resources/Private/Templates/Example/List.html

Common Pitfalls

Pitfall	Symptom	Fix
Missing public: true in Services.yaml	Controller not found / 404	Add controller entry to Services.yaml
Persistence mapping missing for sys_category	InvalidClassException	Create Category shim + Classes.php mapping
Cacheable action shows stale user data	Wrong user's data displayed	Move action to non-cacheable list
ObjectStorage not initialized	"Call to member function on null"	Initialize in __construct() + initializeObject()
DB column missing for relation	Count always 0	Add int(11) unsigned DEFAULT '0' column in ext_tables.sql
configurePlugin vs registerPlugin confused	Plugin not insertable in backend	configurePlugin = ext_localconf.php; registerPlugin = TCA/Overrides