public function __construct($options = [], $headers = [])
{
if (!function_exists('curl_init')) {
throw new ClientException('curl extension is not loaded: http://php.net/curl');
}
$defaultOptions = ['timeout' => 10, 'max_redirects' => 10, 'proxy' => '', 'ssl_certificates' => '@manaphp/Http/Client/ca.pem', 'verify_host' => true];
$this->_options = array_merge($defaultOptions, $options);
$defaultHeaders = ['User-Agent' => 'ManaPHP/httpClient'];
$this->_headers = array_merge($defaultHeaders, $headers);
}