$server = new React\Http\HttpServer(
    new React\Http\Middleware\StreamingRequestMiddleware(),
    function (ServerRequestInterface $request, callable $next) {
        if (($request->getHeader('Content-Encoding')[0] ?? null) === 'gzip') {
            $decompressor = new \Clue\React\Zlib\Decompressor(ZLIB_ENCODING_GZIP);
            /** @var React\Stream\ReadableStreamInterface $body */
            $body = $request->getBody();
            $body->pipe($decompressor);
            $stream = new \React\Http\Io\ReadableBodyStream($decompressor);
            $request = $request->withBody($stream);
        }
        return $next($request);
    },
    function (ServerRequestInterface $request) {

        echo 'Receive data!' . PHP_EOL;
        $body = $request->getBody();

        return new React\Promise\Promise(function ($resolve, $reject) use ($body, ...

/**
 * a hacky private property value extractor from any object
 * @return Closure function(object $object, string $property) {}
 */
function propertyReader(): Closure
{
    return function &(object $object, string $property) {
        $value = &Closure::bind(function &() use ($property) {
            return $this->$property;
        }, $object, $object)->__invoke();
        return $value;
    };
}


$server = new React\Http\HttpServer(
    new StreamingRequestMiddleware(),
    function (ServerRequestInterface $request, callable $next) {
        return $next($request->withAttribute('source-body', $request->getBody()));
    },
    new GzipStreamMiddleware(),
    function (ServerRequestInterface $request, callable $next) {
        /** @var \React\Http\Io\HttpBodyStream $sourceBody */
        $sourceBody = $request->getAttribute('source-body');
        /** @var \React\Http\Io\ChunkedDecoder $input */
        $input = $sourceBody->input; // public property
        $reader = propertyReader();
        /** @var \React\Http\Io\CloseProtectionStream $input */
        $closeInput = $input = $reader($input, 'input'); //input is private, we have to extract it...
        /** @var \React\Socket\Connection $input */
        $input = $reader($input, 'input'); //input is private, we have to extract it...
        $stream = $input->stream; // real stream
        $closeInput->on('close', function () use ($stream) {
            // the close handler from `CloseProtectionStream` is reattached the stream to the loop,
            // we do not need this and this will bring us to the internal PHP max stream count handling.
            // So we remove this stream and right now and all works fine, ugly but effective!
            Loop::get()->removeReadStream($stream);
        });
        return $next($request);
    },
    function (ServerRequestInterface $request) {
//          ...