RequestHeaderParser.php

<?php

namespace React\Http;

use Evenement\EventEmitter;
use Exception;
use RingCentral\Psr7 as g7;

/**
 * @event headers
 * @event error
 *
 * @internal
 */
class RequestHeaderParser extends EventEmitter
{
    private $buffer = '';
    private $maxSize = 4096;

    public function feed($data)
    {
        $this->buffer .= $data;

        $endOfHeader = strpos($this->buffer, "\r\n\r\n");

        if (false !== $endOfHeader) {
            $currentHeaderSize = $endOfHeader;
        } else {
            $currentHeaderSize = strlen($this->buffer);
        }

        if ($currentHeaderSize > $this->maxSize) {
            $this->emit('error', array(new \OverflowException("Maximum header size of {$this->maxSize} exceeded."), $this));
            $this->removeAllListeners();
            return;
        }

        if (false !== $endOfHeader) {
            try {
                $this->parseAndEmitRequest();
            } catch (Exception $exception) {
                $this->emit('error', array($exception));
            }
            $this->removeAllListeners();
        }
    }

    private function parseAndEmitRequest()
    {
        list($request, $bodyBuffer) = $this->parseRequest($this->buffer);
        $this->emit('headers', array($request, $bodyBuffer));
    }

    private function parseRequest($data)
    {
        list($headers, $bodyBuffer) = explode("\r\n\r\n", $data, 2);

        $originalTarget = null;
        if (strpos($headers, 'OPTIONS * ') === 0) {
            $originalTarget = '*';
            $headers = 'OPTIONS / ' . substr($headers, 10);
        } elseif (strpos($headers, 'CONNECT ') === 0) {
            $parts = explode(' ', $headers, 3);
            $uri = parse_url('tcp://' . $parts[1]);

            // check this is a valid authority-form request-target (host:port)
            if (isset($uri['scheme'], $uri['host'], $uri['port']) && count($uri) === 3) {
                $originalTarget = $parts[1];
                $parts[1] = '/';
                $headers = implode(' ', $parts);
            }
        }

        $request = g7\parse_request($headers);

        // Do not assume this is HTTPS when this happens to be port 443
        // detecting HTTPS is left up to the socket layer (TLS detection)
        if ($request->getUri()->getScheme() === 'https') {
            $request = $request->withUri(
                $request->getUri()->withScheme('http')->withPort(443)
            );
        }

        if ($originalTarget !== null) {
            $request = $request->withUri(
                $request->getUri()->withPath(''),
                true
            )->withRequestTarget($originalTarget);
        }

        return array($request, $bodyBuffer);
    }
}