• Benjamin Franzke's avatar
    [FEATURE] Add symfony dependency injection for core and extbase · 0cf8053e
    Benjamin Franzke authored
    This feature is a combined approach using two containers/concepts:
    1) symfony/dependency-injection (now exposed as official TYPO3 API):
       Supports: autoconfiguration, autowiring using Service.{yaml,php}
    2) service providers (fork of the experimental interfaces in
       container-interop/service-provider, sometimes called PSR-11+)
       Supports: factory-style configuration using plain php code
       provided for internal use and possible future public use.
    1) Symfony dependency injection is provided to be used by extensions
    and throughout the TYPO3 core for (auto)wiring of services (classes).
    Extensions can control symfony's dependency injection use a file
    located in Configuration/Services.yaml, if they need more flexibility
    they may also use Configuration/Services.php which can
    use symfony's ContainerConfigurator or ContainerBuilder.
    2) Service providers are used (within TYPO3 core) to provide
    dependency injection for services used in the install tool which require
    failsafe boot. This is based on container-interop/service-provider.
    container-interop/service-provider is supposed to become a PSR but is
    still marked experimental, therefore this commit adds an implementation
    to TYPO3 provided for internal use only – it is not public API.
    We do still include it (as @interal fork) right now, to adapt to this
    upcoming PSR from the very beginning, in order to actually push the
    development of this proposal forward.
    Service providers in failsafe mode are consumed by a simplistic,
    non-compiled container.
    Symfony's container is too slow when running uncached (as the compilation,
    recursive directory lookups and autowiring needs to be performed on every
    invocation). We do not want caching for recovery maintenance tasks
    which would not be able to recover from scenarios with broken caches.
    Services that are configured through service providers, are both available
    in the non compiled install tool container and in the symfony container.
    They do *not* need to be defined twice. The two "worlds" are bridged
    using a ServiceProviderCompilerPass which creates symfony DI definitions
    from service-provider factories. The code is a derivative of the code from
    the (outdated) symfony bundle
     * inject* methods are now supported for all classes (not just Extbase)
       It is suggested to use constructor based injection, this feature
       is available to provide maximum compatibility to the old Extbase DI.
     * Autoconfiguration based on interface implementation.
       (current) autoconfigured interface are:
         SingletonInterface,  MiddlewareInterface, RequestHandlerInterface,
         LoggerAwareInterface, ControllerInterface, ViewHelperInterface
         (we expect more to follow in subsequent commits)
    Included adaptions
    In order to demonstrate and to be able to verify the features of this
    patch, some classes are adapted to use or support dependency injection:
     * RedirectHandler/RedirectService autowired/autoconfigured
     * Application classes and their dependencies are manually wired in
       service providers. This is required as the application runs in fail-
       safe mode when there is no configuration available (first install)
     * MiddlewareStack is composed in service providers and injected
       as a RequestHandler into the Http\Application classes (in order to
       prevent injecting the Container, which would be an anti pattern).
     * Middleware configuration is treated as service (like a registry),
       and retrieval is provided through service providers (the service
       providers default to the existing middleware configuration format)
     * The Middleware dispatcher now first tries to retrieve classes from
       the PSR-11 container, falling back to makeInstance if not available
     * Dependency Injection using symfony for all core Extbase Controllers
     * A Services.yaml is added for each core extension which contains
       classes that are used in frontend/backend context
     * A LateBoot service is added for install tool
    DI vs ext_localconf – loading order, legacy makeInstance support
    Dependency Injection containers solve most of the tasks that
    ext_localconf.php and GeneralUtility::makeInstance solve for Singletons:
    Service configuration and instance management.
    (Symfony) DI could therefore be used to replace both in the long run.
    Both are doing similar tasks when talking about Singletons:
    They create and configure services that are stored and shared in a
    central memory storage (container for DI, GU::$singletonInstances for
    our legacy TYPO3 case). That means they both actually conflict right
    now – in terms of: Who is responsible for creating a class?
    We've made a decision to connect these both: GeneralUtility::makeInstance
    will offload instantiation to the Container if the class is a) available
    and b) no runtime constructor arguments have been passed to makeInstance
    (which symfony DI doesn't support).
    The DI container itself does provides backwards compatibility to XCLASSES
    and class aliases use a new internal helper method makeInstanceForDi.
    ext_localconf's main design flaw is the mixture of initialization
    and configuration composition without assurance that all configuration
    is available before a configuration-dependent class is instantiated.
    Proper DI first reads all configuration and then performs all service
    injections on demand and pre calculated using a dependency tree – and
    therefore always in proper sequence.
    What we *don't* want (+ reasons)
     * Symfony Bundles
       pro: provide a defined way for container configuration)
       con: Requires the Symfony HTTP kernel which is not compatible with PSR7
     * Usage of Symfony\DependencyInjection\ExtensionInterface
       con: It is not useful as it cannot add new compiler passes
     * Handling of prototypes that need dependency injection *and* a way to
       to get custom constructor arguments passed (individual per class)
       While symfony DI can handle prototypes (called 'shared: false'), it
       does not support passing constructor arguments like the Extbase object
       manager does. We'll advocate to using a factory pattern for those
       prototypes instead.
     * Circular dependencies: This is not supported by symfony DI and isn't
       possible with service providers either
    Future changes (left out for brevity)
     * (cli) Build tool to warmup DI cache/state during deployment
     * Adaptions to (all) core dispatchers to prefer a PSR-11
       container over GeneralUtility::makeInstance
    Dependency changes
    composer require symfony/dependency-injection:^4.1 symfony/config:^4.1
    Releases: master
    Resolves: #88689
    Resolves: #84112
    Change-Id: I8efd817066b528a5953c56fdd027cb94b2bb8eb3
    Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/58255
    Tested-by: default avatarTobi Kretschmann <tobi@tobishome.de>
    Tested-by: default avatarJörg Bösche <typo3@joergboesche.de>
    Tested-by: default avatarAlexander Schnitzler <review.typo3.org@alexanderschnitzler.de>
    Tested-by: default avatarTYPO3com <noreply@typo3.com>
    Tested-by: default avatarBenjamin Franzke <bfr@qbus.de>
    Reviewed-by: default avatarTobi Kretschmann <tobi@tobishome.de>
    Reviewed-by: default avatarJörg Bösche <typo3@joergboesche.de>
    Reviewed-by: default avatarAlexander Schnitzler <review.typo3.org@alexanderschnitzler.de>
    Reviewed-by: default avatarBenjamin Franzke <bfr@qbus.de>