MiddlewareStack::create()   A
last analyzed

Complexity

Conditions 2
Paths 2

Size

Total Lines 7
Code Lines 4

Duplication

Lines 0
Ratio 0 %

Importance

Changes 0
Metric Value
cc 2
eloc 4
nc 2
nop 2
dl 0
loc 7
rs 10
c 0
b 0
f 0
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<?php
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declare(strict_types=1);
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namespace Tebe\Pvc\Middleware;
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use Psr\Http\Message\ResponseInterface;
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use Psr\Http\Message\ServerRequestInterface;
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use Psr\Http\Server\MiddlewareInterface;
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use Psr\Http\Server\RequestHandlerInterface;
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class MiddlewareStack implements RequestHandlerInterface
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{
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    /**
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     * @var RequestHandlerInterface
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     */
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    private $requestHandler;
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    /**
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     * @var MiddlewareInterface[]
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     */
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    private $middlewares = [];
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    /**
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     * @param RequestHandlerInterface $requestHandler
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     */
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    private function __construct(RequestHandlerInterface $requestHandler)
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    {
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        $this->requestHandler = $requestHandler;
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    }
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    /**
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     * @param RequestHandlerInterface $requestHandler
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     * @param MiddlewareInterface[] $middlewares LIFO array of middlewares
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     * @return self
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     */
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    public static function create(RequestHandlerInterface $requestHandler, array $middlewares = []): self
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    {
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        $stack = new self($requestHandler);
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        foreach ($middlewares as $middleware) {
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            $stack = $stack->push($middleware);
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        }
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        return $stack;
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    }
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    /**
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     * @param ServerRequestInterface $request
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     * @return ResponseInterface
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     */
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    public function handle(ServerRequestInterface $request): ResponseInterface
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    {
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        $next = $this->peek();
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        if (null === $next) {
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            return $this->requestHandler->handle($request);
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        }
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        return $next->process($request, $this->pop());
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    }
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    /**
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     * Creates a new stack with the given middleware pushed.
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     *
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     * @param MiddlewareInterface $middleware
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     * @return self
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     */
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    public function push(MiddlewareInterface $middleware): self
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    {
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        $stack = clone $this;
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        array_unshift($stack->middlewares, $middleware);
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        return $stack;
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    }
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    /**
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     * @return MiddlewareInterface|null
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     */
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    private function peek()
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    {
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        return reset($this->middlewares) ?: null;
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    }
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    /**
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     * @return self
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     */
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    private function pop(): self
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    {
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        $stack = clone $this;
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        array_shift($stack->middlewares);
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        return $stack;
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    }
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}
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