The framework includes a set of interfaces and components intended to simplify dependency injection and object construction in your application.
Note
Container implementation is fully compatible with PSR-11 Container.
You can always access the container directly in your code by requesting Psr\Container\ContainerInterface:
use Psr\Container\ContainerInterface;
class HomeController
{
public function index(ContainerInterface $container): void
{
dump($container->get(App\App::class));
}
}
Spiral support both method and constructor injections for your classes:
class UserMailer
{
protected Mailer $mailer;
public function __construct(Mailer $mailer)
{
$this->mailer = $mailer;
}
public function do(): void
{
$this->mailer->sendMail(...);
}
}
The Mailer dependency will be automatically delivered by the container (auto-wiring).
Note
Note, your controllers, commands, and jobs support method injection.
You can configure container by creating a set of bindings between aliases or interfaces to concrete implementations.
Use Bootloaders to define bindings.
We can either use Spiral\Core\BinderInterface or Spiral\Core\Container to configure the application container.
To bind interface to concrete implementation:
use Spiral\Core\Container;
//...
public function boot(Container $container): void
{
$container->bind(MyInterface::class, MyImplementation::class);
}
To bind singleton:
use Spiral\Core\Container;
//...
public function boot(Container $container): void
{
$container->bindSingleton(MyImplementation::class, MyImplementation::class);
}
To bind with specific parameters:
use Spiral\Core\Container;
//...
public function boot(Container $container): void
{
$container->bindSingleton(MyImplementation::class, bind(MyImplementation::class, [
'param' => 'value'
]));
}
Note
Read about Config Objects to see how to manage config dependencies.
You can also use closure to configure your class automatically:
use Spiral\Core\Container;
//...
public function boot(Container $container): void
{
$container->bindSingleton(MyImplementation::class, function() {
return new MyImplementation('some-value');
});
}
Closures also support dependencies:
use Spiral\Core\Container;
//...
public function boot(Container $container): void
{
$container->bindSingleton(MyImplementation::class, function(SomeClass $class) {
return new MyImplementation($class);
});
}
To check if container has binding use:
dump($container->has(MyImplementation::class));
To remove the container binding:
$container->removeBinding(MyService::class);
You can skip singleton binding by implementing Spiral\Core\Container\SingletonInterface in your class:
use Spiral\Core\Container\SingletonInterface;
class MyService implements SingletonInterface
{
public function method(): void
{
//...
}
}
Now, the container will automatically treat this class as a singleton in your application:
protected function index(MyService $service)
{
dump($this->container->get(MyService::class) === $service);
}
In some cases, you might want to construct a desired class without resolving all of it's __constructor dependencies.
You can use Spiral\Core\FactoryInterface for that purpose:
public function makeClass(FactoryInterface $factory): MyClass
{
return $factory->make(MyClass::class, [
'parameter' => 'value'
// other dependencies will be resolved automatically
]);
}
If you want to resolve method arguments to dynamic target (i.e., controller method) use Spiral\Core\ResolverInterface:
abstract class Handler
{
protected ResolverInterface $resolver;
public function __construct(ResolverInterface $resolver)
{
$this->resolver = $resolver;
}
public function run(array $params): bool
{
$method = new \ReflectionMethod($this, 'do'); // the method to invoke with method injection
$method->setAccessible(true);
return $method->invokeArgs(
$this,
$this->resolver->resolveArguments($method, $params) // resolve missing arguments
);
}
}
Method do now can request method injection:
class MyHandler extends Handler
{
public function do(SomeClass $some): bool
{
// ...
}
}
In some cases, you might want to invoke a desired method with auto wiring all of it's dependencies.
You can use Spiral\Core\InvokerInterface for that purpose:
public function invokeMethod(\Spiral\Core\InvokerInterface $invoker): mixed
{
return $invoker->invoke([$instance, 'handle'], [
'parameter' => 'value'
// other dependencies will be resolved automatically
]);
}
if you pass as first callable array value a string ['foo', 'bar'], so it will be requested from the container.
$container->bind('some-job', SomeJob::class);
// ...
public function invokeMethod(\Spiral\Core\InvokerInterface $invoker): mixed
{
return $invoker->invoke(['some-job', 'handle'], [ // some-job will be requested from the container
'parameter' => 'value'
// other dependencies will be resolved automatically
]);
}
Note
Invokable method can have aspublicasprotectedandprivitevisibility.
In some cases, you might want to invoke a desired closure with auto wiring all of it's dependencies.
public function invokeMethod(\Spiral\Core\InvokerInterface $invoker): mixed
{
return $invoker->invoke(function (MyClass $class, string $parameter) {
return new MyClassService($class);
}, [
'parameter' => 'value'
// other dependencies will be resolved automatically
]);
}
Spiral Framework attempts to hide the container implementation and configuration from your domain layer by providing rich auto-wiring functionality. Though auto-wiring rules are straightforward, it's essential to learn them to avoid framework misbehavior.
Framework container can automatically resolve the constructor or method dependencies by providing instances of concrete classes.
class MyController
{
public function __construct(
OtherClass $class,
SomeInterface $some
) {
}
}
In a provided example, the container will attempt to give the instance of OtherClass by automatically constructing it.
However, SomeInterface would not be resolved unless you have the proper binding in your container.
$container->bind(SomeInterface::class, SomeClass::class);
Please note, the container will try to resolve all constructor dependencies (unless you manually provide some values). It means that all class dependencies must be available, or parameter must be declared as optional:
// will fail if `value` dependency not provided
__construct(OtherClass $class, $value)
// will use `null` as `value` if no other value provided
__construct(OtherClass $class, $value = null)
// will fail if SomeInterface does not point to the concrete implementation
__construct(OtherClass $class, SomeInterface $some)
// will use null as value of `some` if no concrete implementation is provided
__construct(OtherClass $class, SomeInterface $some = null)
In addition to regular method injections, the container can resolve the injection context automatically. Such a technique provides us the ability to request multiple databases using the following statement:
protected function index(Database $primary, Database $secondary): void
{
dump($primary);
dump($secondary);
}
Note
Whereprimaryandsecondaryare database names.
Implement Spiral\Core\Container\InjectorInterface to create injection factory and define class responsible for such
injections:
class MyClassInjector implements InjectorInterface
{
public function createInjection(\ReflectionClass $class, string $context = null)
{
return new MyClass($context);
}
}
Where MyClass is:
class MyClass
{
public string $name;
public function __construct(string $name)
{
$this->name = $name;
}
}
Make sure to register inject in the container:
$container->bindInjector(MyClass::class, MyClassInjector::class);
As a result we can request instance of MyClass using method arguments:
public function method(MyClass $john, MyClass $bob): void
{
dump($john); // $john->name === 'john'
dump($bob); // $bob->name === 'bob'
}
You can always bypass contextual injection in Spiral\Core\FactoryInterface:
dump($factory->make(MyClass::class, ['name' => 'abc']));
A lot of internal application services reside in a memory in the form of singleton objects. Such objects do not
implement static getInstance, but rather configured to remain in container between requests.
Declaring your service or controller as a singleton is the shortest path to get small performance improvement, however, some rules must be applied to avoid memory and state leaks.
The framework provides multiple ways to declare a class object as a singleton. At first, you can create Bootloader in which you can bind class under its name:
class ServiceBootloader extends Bootloader
{
protected const SINGLETONS = [
Service::class => Service::class
];
}
Now, you will always receive the same instance from the IoC container by doing the injection.
The alternative approach does not require Bootloader and can be defined via class itself, implement
interface Spiral\Core\Container\SingletonInterface to declare to the container that class must be constructed only
once:
use Spiral\Core\Container\SingletonInterface;
class Service implements SingletonInterface
{
// ...
}
Note
You can implement a singleton interface in services, controllers, middleware, etc. Do not implement it in Repositories and mappers as these classes state are managed by ORM.
By keeping your services in memory between requests, you can avoid doing some complex initializations and computations over and over. However, you must remember that your services must be designed in stateless fashion and do not contain any user data.
You can not:
Spiral\Http\Request\InputManager instead)Spiral\Session\SessionScope instead)Spiral\Security\GuardScope instead)You are allowed to store data in services that can not change between user requests. For example, if your application relies on heavy XML as configuration source:
class Service implements SingletonService
{
private ?array $configCache = null;
public function getConfig(): array
{
if ($this->configCache !== null) {
return $this->configCache;
}
$this->configCache = $this->readConfig(); // heavy operation
return $this->configCache;
}
}
Using such an approach, you can perform complex computations only once and rely on RAM cache on later user requests.