Psr7Middlewares\Middleware\MethodOverride::getOverrideMethod PHP Метод

    private function getOverrideMethod(ServerRequestInterface $request)
    {
        if ($request->getMethod() === 'POST' && $this->postParam !== null) {
            $params = $request->getParsedBody();
            if (isset($params[$this->postParam])) {
                return strtoupper($params[$this->postParam]);
            }
        } elseif ($request->getMethod() === 'GET' && $this->getParam !== null) {
            $params = $request->getQueryParams();
            if (isset($params[$this->getParam])) {
                return strtoupper($params[$this->getParam]);
            }
        }
        return strtoupper($request->getHeaderLine(self::HEADER));
    }