Ergo\Http\Client::_buildRequest PHP Method

    private function _buildRequest($method, $path, $body = null, $contentType = null)
    {
        // copy default headers
        $headers = $this->_headers;
        // add Content-Type header if provided
        if ($contentType) {
            $headers[] = new HeaderField('Content-Type', $contentType);
        }
        $request = new Request($method, $this->_url->getUrlForRelativePath($path), $headers, $body);
        // pass the request through the filter chain
        foreach ($this->_filters as $filter) {
            $request = $filter->request($request);
        }
        return $request;
    }