Yiisoft\Middleware\Dispatcher\MiddlewareFactory::wrapCallable()

Size

Total Lines	69
Code Lines	30

Duplication

Lines	0
Ratio	0 %

Importance

Changes	14
Bugs	7	Features	0

4 Methods

Rating	Name	Duplication	Size	Complexity
A	MiddlewareFactory.php$0 ➔ __construct()	0	5	1
A	MiddlewareFactory.php$1 ➔ __construct()	0	4	1
A	MiddlewareFactory.php$1 ➔ process()	0	16	3
A	MiddlewareFactory.php$0 ➔ process()	0	18	2

<?php

declare(strict_types=1);

namespace Yiisoft\Middleware\Dispatcher;

use Closure;
use Psr\Container\ContainerInterface;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Server\MiddlewareInterface;
use Psr\Http\Server\RequestHandlerInterface;
use ReflectionNamedType;
use Yiisoft\Injector\Injector;

use function in_array;
use function is_array;
use function is_string;

/**
 * Creates a PSR-15 middleware based on the definition provided.
 */
final class MiddlewareFactory implements MiddlewareFactoryInterface
{
    private ContainerInterface $container;

    /**
     * @param ContainerInterface $container Container to use for resolving definitions.
     */
    public function __construct(ContainerInterface $container)
    {
        $this->container = $container;
    }

    /**
     * @param array|callable|string $middlewareDefinition Middleware definition in one of the following formats:
     *
     * - A name of PSR-15 middleware class. The middleware instance will be obtained from container and executed.
     * - A callable with `function(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface`
     *   signature.
     * - A controller handler action in format `[TestController::class, 'index']`. `TestController` instance will
     *   be created and `index()` method will be executed.
     * - A function returning a middleware. The middleware returned will be executed.
     *
     * For handler action and callable
     * typed parameters are automatically injected using dependency injection container.
     * Current request and handler could be obtained by type-hinting for {@see ServerRequestInterface}
     * and {@see RequestHandlerInterface}.
     */
    public function create($middlewareDefinition): MiddlewareInterface
    {
        $this->validateMiddleware($middlewareDefinition);

        if (is_string($middlewareDefinition)) {
            /** @var MiddlewareInterface */
            return $this->container->get($middlewareDefinition);
        }

        return $this->wrapCallable($middlewareDefinition);
    }

    /**
     * @param array|callable $callback
     */
    private function wrapCallable($callback): MiddlewareInterface
    {
        if (is_array($callback)) {
            return new class ($this->container, $callback) implements MiddlewareInterface {
                /**
                 * @psalm-var class-string
                 */
                private string $class;
                private string $method;
                private ContainerInterface $container;
                private array $callback;

                public function __construct(ContainerInterface $container, array $callback)
                {
                    [$this->class, $this->method] = $callback;
                    $this->container = $container;
                    $this->callback = $callback;
                }

                public function process(
                    ServerRequestInterface $request,
                    RequestHandlerInterface $handler
                ): ResponseInterface {
                    /** @var mixed $controller */
                    $controller = $this->container->get($this->class);

                    /** @var mixed $response */
                    $response = (new Injector($this->container))
                        ->invoke(
                            [$controller, $this->method],
                            MiddlewareFactory::resolveHandlerArguments($this->callback, $request, $handler)
                        );
                    if ($response instanceof ResponseInterface) {
                        return $response;
                    }

                    throw new InvalidMiddlewareDefinitionException($this->callback);
                }
            };
        }

        /** @var callable|Closure $callback */

        return new class ($callback, $this->container) implements MiddlewareInterface {
            private ContainerInterface $container;
            private $callback;

            public function __construct(callable $callback, ContainerInterface $container)
            {
                $this->callback = $callback;
                $this->container = $container;
            }

            public function process(
                ServerRequestInterface $request,
                RequestHandlerInterface $handler
            ): ResponseInterface {
                /** @var mixed $response */
                $response = (new Injector($this->container))->invoke(
                    $this->callback,
                    MiddlewareFactory::resolveHandlerArguments($this->callback, $request, $handler)
                );
                if ($response instanceof ResponseInterface) {
                    return $response;
                }
                if ($response instanceof MiddlewareInterface) {
                    return $response->process($request, $handler);
                }
                throw new InvalidMiddlewareDefinitionException($this->callback);
            }
        };
    }

    /**
     * @param array|callable|string $middlewareDefinition A name of PSR-15 middleware, a callable with
     * `function(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface` signature or
     * a handler action (an array of [handlerClass, handlerMethod]). For handler action and callable typed parameters
     * are automatically injected using dependency injection container passed to the route.
     * Current request and handler could be obtained by type-hinting for {@see ServerRequestInterface}
     * and {@see RequestHandlerInterface}.
     *
     * @throws InvalidMiddlewareDefinitionException
     */
    private function validateMiddleware($middlewareDefinition): void
    {
        if (is_string($middlewareDefinition) && is_subclass_of($middlewareDefinition, MiddlewareInterface::class)) {
            return;
        }

        if ($this->isCallable($middlewareDefinition)) {
            return;
        }

        throw new InvalidMiddlewareDefinitionException($middlewareDefinition);
    }

    /**
     * @param mixed $definition
     */
    private function isCallable($definition): bool
    {
        if ($definition instanceof Closure) {
            return true;
        }

        return is_array($definition)
            && array_keys($definition) === [0, 1]
            && is_string($definition[0])
            && is_string($definition[1])
            && in_array(
                $definition[1],
                class_exists($definition[0]) ? get_class_methods($definition[0]) : [],
                true
            );
    }

    /**
     * @param callable|Closure $callback
     * @param ServerRequestInterface $request
     * @param RequestHandlerInterface $handler
     *
     * @throws \ReflectionException
     *
     * @return array
     *
     * @internal
     */
    public static function resolveHandlerArguments(
        $callback,
        ServerRequestInterface $request,
        RequestHandlerInterface $handler
    ): array {
        if (is_array($callback)) {
            [$class, $method] = $callback;
            $parameters = (new \ReflectionMethod($class, $method))->getParameters();
        } else {
            $parameters = (new \ReflectionFunction(Closure::fromCallable($callback)))->getParameters();
        }
        /** @psalm-var array{array-key, mixed} $arguments */
        $arguments = [];

        foreach ($parameters as $parameter) {
            if (
                $parameter->hasType()
                && $parameter->getType() instanceof ReflectionNamedType
                && !$parameter->getType()->isBuiltin()
            ) {
                if ($parameter->getType()->getName() === ServerRequestInterface::class) {
                    $arguments[$parameter->getName()] = $request;
                } elseif ($parameter->getType()->getName() === RequestHandlerInterface::class) {
                    $arguments[$parameter->getName()] = $handler;
                }
            } elseif (array_key_exists($parameter->getName(), $request->getAttributes())) {
                $arguments[$parameter->getName()] = $request->getAttribute($parameter->getName());
            }
        }
        return $arguments;
    }
}