Elastica\Transport\Guzzle::_createPsr7Request PHP Метод

    protected function _createPsr7Request(Request $request, Connection $connection)
    {
        $req = new Psr7\Request($request->getMethod(), $this->_getActionPath($request), $connection->hasConfig('headers') && is_array($connection->getConfig('headers')) ? $connection->getConfig('headers') : []);
        $data = $request->getData();
        if (!empty($data) || '0' === $data) {
            if ($req->getMethod() == Request::GET) {
                $req = $req->withMethod(Request::POST);
            }
            if ($this->hasParam('postWithRequestBody') && $this->getParam('postWithRequestBody') == true) {
                $request->setMethod(Request::POST);
                $req = $req->withMethod(Request::POST);
            }
            $req = $req->withBody(Psr7\stream_for(is_array($data) ? JSON::stringify($data, JSON_UNESCAPED_UNICODE) : $data));
        }
        return $req;
    }