UPGRADE FROM 4.3 to 4.4
=======================

Cache
-----

 * Added argument `$prefix` to `AdapterInterface::clear()`
 * Marked the `CacheDataCollector` class as `@final`.

Console
-------

 * Deprecated finding hidden commands using an abbreviation, use the full name instead
 * Deprecated returning `null` from `Command::execute()`, return `0` instead
 * Deprecated the `Application::renderException()` and `Application::doRenderException()` methods,
   use `renderThrowable()` and `doRenderThrowable()` instead.

Debug
-----

 * Deprecated the component in favor of the `ErrorHandler` component
 * Replace uses of `Symfony\Component\Debug\Debug` by `Symfony\Component\ErrorHandler\Debug`

Config
------

 * Deprecated overriding the `FilerLoader::import()` method without declaring the optional `$exclude` argument

DependencyInjection
-------------------

 * Made singly-implemented interfaces detection be scoped by file
 * Deprecated support for short factories and short configurators in Yaml

   Before:
   ```yaml
   services:
       my_service:
           factory: factory_service:method
   ```

   After:
   ```yaml
   services:
       my_service:
           factory: ['@factory_service', method]
   ```

 * Passing an instance of `Symfony\Component\DependencyInjection\Parameter` as class name to `Symfony\Component\DependencyInjection\Definition` is deprecated.

   Before:
   ```php
   new Definition(new Parameter('my_class'));
   ```

   After:
   ```php
   new Definition('%my_class%');
   ```

DoctrineBridge
--------------
 * Deprecated injecting `ClassMetadataFactory` in `DoctrineExtractor`, an instance of `EntityManagerInterface` should be
   injected instead.
 * Deprecated passing an `IdReader` to the `DoctrineChoiceLoader` when the query cannot be optimized with single id field.
 * Deprecated not passing an `IdReader` to the `DoctrineChoiceLoader` when the query can be optimized with single id field.
 * Deprecated `RegistryInterface`, use `Doctrine\Persistence\ManagerRegistry`.
 * Added a new `getMetadataDriverClass` method to replace class parameters in `AbstractDoctrineExtension`. This method
   will be abstract in Symfony 5 and must be declared in extending classes.

Filesystem
----------

 * Support for passing a `null` value to `Filesystem::isAbsolutePath()` is deprecated.

Form
----

 * Using different values for the "model_timezone" and "view_timezone" options of the `TimeType` without configuring a
   reference date is deprecated.
 * Using `int` or `float` as data for the `NumberType` when the `input` option is set to `string` is deprecated.
 * Overriding the methods `FormIntegrationTestCase::setUp()`, `TypeTestCase::setUp()` and `TypeTestCase::tearDown()` without the `void` return-type is deprecated.

FrameworkBundle
---------------

 * Deprecated calling `WebTestCase::createClient()` while a kernel has been booted, ensure the kernel is shut down before calling the method
 * Deprecated support for `templating` engine in `TemplateController`, use Twig instead
 * The `$parser` argument of `ControllerResolver::__construct()` and `DelegatingLoader::__construct()`
   has been deprecated.
 * The `ControllerResolver` and `DelegatingLoader` classes have been marked as `final`.
 * The `controller_name_converter` and `resolve_controller_name_subscriber` services have been deprecated.
 * Deprecated `routing.loader.service`, use `routing.loader.container` instead.
 * Not tagging service route loaders with `routing.route_loader` has been deprecated.
 * Overriding the methods `KernelTestCase::tearDown()` and `WebTestCase::tearDown()` without the `void` return-type is deprecated.
 * Marked the `RouterDataCollector` class as `@final`.

HttpClient
----------

 * Added method `cancel()` to `ResponseInterface`

HttpFoundation
--------------

 * `ApacheRequest` is deprecated, use `Request` class instead.
 * Passing a third argument to `HeaderBag::get()` is deprecated since Symfony 4.4, use method `all()` instead
 * [BC BREAK] `PdoSessionHandler` with MySQL changed the type of the lifetime column,
   make sure to run `ALTER TABLE sessions MODIFY sess_lifetime INTEGER UNSIGNED NOT NULL` to
   update your database.
 * `PdoSessionHandler` now precalculates the expiry timestamp in the lifetime column,
    make sure to run `CREATE INDEX EXPIRY ON sessions (sess_lifetime)` to update your database
    to speed up garbage collection of expired sessions.

HttpKernel
----------

 * The `DebugHandlersListener` class has been marked as `final`
 * Added new Bundle directory convention consistent with standard skeletons:

    ```
    └── MyBundle/
        ├── config/
        ├── public/
        ├── src/
        │   └── MyBundle.php
        ├── templates/
        └── translations/
    ```

   To make this work properly, it is necessary to change the root path of the bundle:

    ```php
    class MyBundle extends Bundle
    {
        public function getPath(): string
        {
            return \dirname(__DIR__);
        }
    }
    ```

   As many bundles must be compatible with a range of Symfony versions, the current
   directory convention is not deprecated yet, but it will be in the future.

 * Deprecated the second and third argument of `KernelInterface::locateResource`
 * Deprecated the second and third argument of `FileLocator::__construct`
 * Deprecated loading resources from `%kernel.root_dir%/Resources` and `%kernel.root_dir%` as
   fallback directories. Resources like service definitions are usually loaded relative to the
   current directory or with a glob pattern. The fallback directories have never been advocated
   so you likely do not use those in any app based on the SF Standard or Flex edition.
 * Getting the container from a non-booted kernel is deprecated
 * Marked the `AjaxDataCollector`, `ConfigDataCollector`, `EventDataCollector`,
   `ExceptionDataCollector`, `LoggerDataCollector`, `MemoryDataCollector`,
   `RequestDataCollector` and `TimeDataCollector` classes as `@final`.
 * Marked the `RouterDataCollector::collect()` method as `@final`.
 * The `DataCollectorInterface::collect()` and `Profiler::collect()` methods third parameter signature
   will be `\Throwable $exception = null` instead of `\Exception $exception = null` in Symfony 5.0.
 * Deprecated methods `ExceptionEvent::get/setException()`, use `get/setThrowable()` instead
 * Deprecated class `ExceptionListener`, use `ErrorListener` instead

Lock
----

 * Deprecated `Symfony\Component\Lock\StoreInterface` in favor of `Symfony\Component\Lock\BlockingStoreInterface` and
   `Symfony\Component\Lock\PersistingStoreInterface`.
 * `Factory` is deprecated, use `LockFactory` instead
 * Deprecated services `lock.store.flock`, `lock.store.semaphore`, `lock.store.memcached.abstract` and `lock.store.redis.abstract`,
   use `StoreFactory::createStore` instead.

Mailer
------

 * [BC BREAK] Changed the DSN to use for disabling delivery (using the `NullTransport`) from `smtp://null` to `null://null` (host doesn't matter).
 * [BC BREAK] Renamed class `SmtpEnvelope` to `Envelope` and `DelayedSmtpEnvelope` to `DelayedEnvelope`.
 * [BC BREAK] Added a required `string $transport` argument to `MessageEvent::__construct`.

Messenger
---------

 * [BC BREAK] Removed `SendersLocatorInterface::getSenderByAlias` added in 4.3.
 * [BC BREAK] Removed `$retryStrategies` argument from `Worker::__construct`.
 * [BC BREAK] Changed arguments of `ConsumeMessagesCommand::__construct`.
 * [BC BREAK] Removed `$senderClassOrAlias` argument from `RedeliveryStamp::__construct`.
 * [BC BREAK] Removed `UnknownSenderException`.
 * [BC BREAK] Removed `WorkerInterface`.
 * [BC BREAK] Removed `$onHandledCallback` of `Worker::run(array $options = [], callable $onHandledCallback = null)`.
 * [BC BREAK] Removed `StopWhenMemoryUsageIsExceededWorker` in favor of `StopWorkerOnMemoryLimitListener`.
 * [BC BREAK] Removed `StopWhenMessageCountIsExceededWorker` in favor of `StopWorkerOnMessageLimitListener`.
 * [BC BREAK] Removed `StopWhenTimeLimitIsReachedWorker` in favor of `StopWorkerOnTimeLimitListener`.
 * [BC BREAK] Removed `StopWhenRestartSignalIsReceived` in favor of `StopWorkerOnRestartSignalListener`.
 * Marked the `MessengerDataCollector` class as `@final`.

Mime
----

 * Removed `NamedAddress`, use `Address` instead (which supports a name now)

MonologBridge
--------------

 * The `RouteProcessor` has been marked final.

Process
-------

 * Deprecated the `Process::inheritEnvironmentVariables()` method: env variables are always inherited.

PropertyAccess
--------------

 * Deprecated passing `null` as 2nd argument of `PropertyAccessor::createCache()` method (`$defaultLifetime`), pass `0` instead.

Routing
-------

 * Deprecated `ServiceRouterLoader` in favor of `ContainerLoader`.
 * Deprecated `ObjectRouteLoader` in favor of `ObjectLoader`.

Security
--------

 * The `LdapUserProvider` class has been deprecated, use `Symfony\Component\Ldap\Security\LdapUserProvider` instead.
 * Implementations of `PasswordEncoderInterface` and `UserPasswordEncoderInterface` should add a new `needsRehash()` method
 * Deprecated returning a non-boolean value when implementing `Guard\AuthenticatorInterface::checkCredentials()`. Please explicitly return `false` to indicate invalid credentials.
 * The `ListenerInterface` is deprecated, extend `AbstractListener` instead.
 * Deprecated passing more than one attribute to `AccessDecisionManager::decide()` and `AuthorizationChecker::isGranted()` (and indirectly the `is_granted()` Twig and ExpressionLanguage function)

   **Before**
   ```php
   if ($this->authorizationChecker->isGranted(['ROLE_USER', 'ROLE_ADMIN'])) {
       // ...
   }
   ```

   **After**
   ```php
   if ($this->authorizationChecker->isGranted(new Expression("is_granted('ROLE_USER') or is_granted('ROLE_ADMIN')"))) {}

   // or:
   if ($this->authorizationChecker->isGranted('ROLE_USER')
      || $this->authorizationChecker->isGranted('ROLE_ADMIN')
   ) {}
   ```

SecurityBundle
--------------

 * Marked the `SecurityDataCollector` class as `@final`.

Serializer
----------

 * Deprecated the `XmlEncoder::TYPE_CASE_ATTRIBUTES` constant. Use `XmlEncoder::TYPE_CAST_ATTRIBUTES` instead.

Stopwatch
---------

 * Deprecated passing `null` as 1st (`$id`) argument of `Section::get()` method, pass a valid child section identifier instead.

Translation
-----------

 * Deprecated support for using `null` as the locale in `Translator`.
 * Deprecated accepting STDIN implicitly when using the `lint:xliff` command, use `lint:xliff -` (append a dash) instead to make it explicit.
 * Marked the `TranslationDataCollector` class as `@final`.

TwigBridge
----------

 * Deprecated to pass `$rootDir` and `$fileLinkFormatter` as 5th and 6th argument respectively to the
   `DebugCommand::__construct()` method, swap the variables position.
 * Deprecated accepting STDIN implicitly when using the `lint:twig` command, use `lint:twig -` (append a dash) instead to make it explicit.
 * Marked the `TwigDataCollector` class as `@final`.

TwigBundle
----------

 * Deprecated `twig.exception_controller` configuration option.

   If you were not using this option previously, set it to `null`:

   After:
   ```yaml
   twig:
       exception_controller: null
   ```

   If you were using this option previously, set it to `null` and use `framework.error_controller` instead:

   Before:
   ```yaml
   twig:
       exception_controller: 'App\Controller\MyExceptionController'
   ```

   After:
   ```yaml
   twig:
       exception_controller: null

   framework:
       error_controller: 'App\Controller\MyExceptionController'
   ```

   The new default exception controller will also change the error response content according to
   https://tools.ietf.org/html/rfc7807 for `json`, `xml`, `atom` and `txt` formats:

   Before (HTTP status code `200`):
   ```json
   {
       "error": {
           "code": 404,
           "message": "Sorry, the page you are looking for could not be found"
       }
   }
   ```

   After (HTTP status code `404`):
   ```json
   {
       "title": "Not Found",
       "status": 404,
       "detail": "Sorry, the page you are looking for could not be found"
   }
   ```

 * Deprecated the `ExceptionController` and `PreviewErrorController` controllers, use `ErrorController` from the HttpKernel component instead
 * Deprecated all built-in error templates, use the error renderer mechanism of the `ErrorHandler` component
 * Deprecated loading custom error templates in non-html formats. Custom HTML error pages based on Twig keep working as before:

   Before (`templates/bundles/TwigBundle/Exception/error.json.twig`):
   ```twig
   {
       "type": "https://example.com/error",
       "title": "{{ status_text }}",
       "status": {{ status_code }}
   }
   ```

   After (`App\Serializer\ProblemJsonNormalizer`):
   ```php
   class ProblemJsonNormalizer implements NormalizerInterface
   {
       public function normalize($exception, $format = null, array $context = [])
       {
           return [
               'type' => 'https://example.com/error',
               'title' => $exception->getStatusText(),
               'status' => $exception->getStatusCode(),
           ];
       }

       public function supportsNormalization($data, $format = null)
       {
           return 'json' === $format && $data instanceof FlattenException;
       }
   }
   ```

Validator
---------

 * [BC BREAK] Using null as `$classValidatorRegexp` value in `DoctrineLoader::__construct` or `PropertyInfoLoader::__construct` will not enable auto-mapping for all classes anymore, use `'{.*}'` instead.
 * Deprecated passing an `ExpressionLanguage` instance as the second argument of `ExpressionValidator::__construct()`.
 * Deprecated using anything else than a `string` as the code of a `ConstraintViolation`, a `string` type-hint will
   be added to the constructor of the `ConstraintViolation` class and to the `ConstraintViolationBuilder::setCode()`
   method in 5.0.
 * Deprecated passing an `ExpressionLanguage` instance as the second argument of `ExpressionValidator::__construct()`.
   Pass it as the first argument instead.
 * The `Length` constraint expects the `allowEmptyString` option to be defined
   when the `min` option is used.
   Set it to `true` to keep the current behavior and `false` to reject empty strings.
   In 5.0, it'll become optional and will default to `false`.
 * Overriding the methods `ConstraintValidatorTestCase::setUp()` and `ConstraintValidatorTestCase::tearDown()` without the `void` return-type is deprecated.
 * deprecated `Symfony\Component\Validator\Mapping\Cache\CacheInterface` and all implementations in favor of PSR-6.
 * deprecated `ValidatorBuilder::setMetadataCache`, use `ValidatorBuilder::setMappingCache` instead.
 * The `Range` constraint has a new message option `notInRangeMessage` that is used when both `min` and `max` values are set.
   In case you are using custom translations make sure to add one for this new message.
 * Marked the `ValidatorDataCollector` class as `@final`.

WebProfilerBundle
-----------------

 * Deprecated the `ExceptionController` class in favor of `ExceptionErrorController`
 * Deprecated the `TemplateManager::templateExists()` method

WebServerBundle
---------------

 * The bundle is deprecated and will be removed in 5.0.

Yaml
----

 * Deprecated accepting STDIN implicitly when using the `lint:yaml` command, use `lint:yaml -` (append a dash) instead to make it explicit.
