<?php
/**
* Slim Framework (https://slimframework.com)
*
* @license https://github.com/slimphp/Slim/blob/4.x/LICENSE.md (MIT License)
*/
declare(strict_types=1);
namespace Slim;
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 RuntimeException;
use Slim\Interfaces\AdvancedCallableResolverInterface;
use Slim\Interfaces\CallableResolverInterface;
use Slim\Interfaces\MiddlewareDispatcherInterface;
use function class_exists;
use function function_exists;
use function is_callable;
use function is_string;
use function preg_match;
use function sprintf;
class MiddlewareDispatcher implements MiddlewareDispatcherInterface
{
/**
* Tip of the middleware call stack
*/
protected RequestHandlerInterface $tip;
protected ?CallableResolverInterface $callableResolver;
protected ?ContainerInterface $container;
public function __construct(
RequestHandlerInterface $kernel,
?CallableResolverInterface $callableResolver = null,
?ContainerInterface $container = null
) {
$this->seedMiddlewareStack($kernel);
$this->callableResolver = $callableResolver;
$this->container = $container;
}
/**
* {@inheritdoc}
*/
public function seedMiddlewareStack(RequestHandlerInterface $kernel): void
{
$this->tip = $kernel;
}
/**
* Invoke the middleware stack
*/
public function handle(ServerRequestInterface $request): ResponseInterface
{
return $this->tip->handle($request);
}
/**
* Add a new middleware to the stack
*
* Middleware are organized as a stack. That means middleware
* that have been added before will be executed after the newly
* added one (last in, first out).
*
* @param MiddlewareInterface|string|callable $middleware
*/
public function add($middleware): MiddlewareDispatcherInterface
{
if ($middleware instanceof MiddlewareInterface) {
return $this->addMiddleware($middleware);
}
if (is_string($middleware)) {
return $this->addDeferred($middleware);
}
if (is_callable($middleware)) {
return $this->addCallable($middleware);
}
/** @phpstan-ignore-next-line */
throw new RuntimeException(
'A middleware must be an object/class name referencing an implementation of ' .
'MiddlewareInterface or a callable with a matching signature.'
);
}
/**
* Add a new middleware to the stack
*
* Middleware are organized as a stack. That means middleware
* that have been added before will be executed after the newly
* added one (last in, first out).
*/
public function addMiddleware(MiddlewareInterface $middleware): MiddlewareDispatcherInterface
{
$next = $this->tip;
$this->tip = new class ($middleware, $next) implements RequestHandlerInterface {
private MiddlewareInterface $middleware;
private RequestHandlerInterface $next;
public function __construct(MiddlewareInterface $middleware, RequestHandlerInterface $next)
{
$this->middleware = $middleware;
$this->next = $next;
}
public function handle(ServerRequestInterface $request): ResponseInterface
{
return $this->middleware->process($request, $this->next);
}
};
return $this;
}
/**
* Add a new middleware by class name
*
* Middleware are organized as a stack. That means middleware
* that have been added before will be executed after the newly
* added one (last in, first out).
*/
public function addDeferred(string $middleware): self
{
$next = $this->tip;
$this->tip = new class (
$middleware,
$next,
$this->container,
$this->callableResolver
) implements RequestHandlerInterface {
private string $middleware;
private RequestHandlerInterface $next;
private ?ContainerInterface $container;
private ?CallableResolverInterface $callableResolver;
public function __construct(
string $middleware,
RequestHandlerInterface $next,
?ContainerInterface $container = null,
?CallableResolverInterface $callableResolver = null
) {
$this->middleware = $middleware;
$this->next = $next;
$this->container = $container;
$this->callableResolver = $callableResolver;
}
public function handle(ServerRequestInterface $request): ResponseInterface
{
if ($this->callableResolver instanceof AdvancedCallableResolverInterface) {
$callable = $this->callableResolver->resolveMiddleware($this->middleware);
return $callable($request, $this->next);
}
$callable = null;
if ($this->callableResolver instanceof CallableResolverInterface) {
try {
$callable = $this->callableResolver->resolve($this->middleware);
} catch (RuntimeException $e) {
// Do Nothing
}
}
if (!$callable) {
$resolved = $this->middleware;
$instance = null;
$method = null;
// Check for Slim callable as `class:method`
if (preg_match(CallableResolver::$callablePattern, $resolved, $matches)) {
$resolved = $matches[1];
$method = $matches[2];
}
if ($this->container && $this->container->has($resolved)) {
$instance = $this->container->get($resolved);
if ($instance instanceof MiddlewareInterface) {
return $instance->process($request, $this->next);
}
} elseif (!function_exists($resolved)) {
if (!class_exists($resolved)) {
throw new RuntimeException(sprintf('Middleware %s does not exist', $resolved));
}
$instance = new $resolved($this->container);
}
if ($instance && $instance instanceof MiddlewareInterface) {
return $instance->process($request, $this->next);
}
$callable = $instance ?? $resolved;
if ($instance && $method) {
$callable = [$instance, $method];
}
if ($this->container && $callable instanceof Closure) {
$callable = $callable->bindTo($this->container);
}
}
if (!is_callable($callable)) {
throw new RuntimeException(
sprintf(
'Middleware %s is not resolvable',
$this->middleware
)
);
}
return $callable($request, $this->next);
}
};
return $this;
}
/**
* Add a (non-standard) callable middleware to the stack
*
* Middleware are organized as a stack. That means middleware
* that have been added before will be executed after the newly
* added one (last in, first out).
*/
public function addCallable(callable $middleware): self
{
$next = $this->tip;
if ($this->container && $middleware instanceof Closure) {
/** @var Closure $middleware */
$middleware = $middleware->bindTo($this->container);
}
$this->tip = new class ($middleware, $next) implements RequestHandlerInterface {
/**
* @var callable
*/
private $middleware;
/**
* @var RequestHandlerInterface
*/
private $next;
public function __construct(callable $middleware, RequestHandlerInterface $next)
{
$this->middleware = $middleware;
$this->next = $next;
}
public function handle(ServerRequestInterface $request): ResponseInterface
{
return ($this->middleware)($request, $this->next);
}
};
return $this;
}
}