public function make_http_request($uri, $headers, $content)
    {
        $post = curl_init($uri);
        curl_setopt_array($post, array(
            CURLOPT_POST => true,
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_HTTPHEADER => $headers,
            CURLOPT_POSTFIELDS => json_encode($content)
        ));
        $response = curl_exec($post);
        if (curl_error($post) != '')
            throw new \RuntimeException('Failed to publish: ' . 
                    curl_error($post));
        return array($response, 
                intval(curl_getinfo($post, CURLINFO_HTTP_CODE)));
    }