Request

15class Request implements RequestInterface16{17    use MessageTrait;18    use RequestTrait;19    /**20     * @param string $method HTTP method21     * @param string|UriInterface $uri URI22     * @param array $headers Request headers23     * @param string|resource|StreamInterface|null $body Request body24     * @param string $version Protocol version25     */26    public function __construct(string $method, $uri, array $headers = [], $body = null, string $version = '1.1')27    {28        if (!$uri instanceof UriInterface) {29            $uri = new Uri($uri);30        }31        $this->method = $method;32        $this->uri = $uri;33        $this->setHeaders($headers);34        $this->protocol = $version;35        if (!$this->hasHeader('Host')) {36            $this->updateHostFromUri();37        }38        // If we got no body, defer initialization of the stream until Request::getBody()39        if ('' !== $body && null !== $body) {40            $this->stream = Stream::create($body);41        }42    }43}