$this->load->library("unirest");
$response = $this->unirest->get($url, $headers = array());
$response = $this->unirest->post($url, $headers = array(), $body = NULL);
$response = $this->unirest->put($url, $headers = array(), $body = NULL);
$response = $this->unirest->patch($url, $headers = array(), $body = NULL);
$response = $this->unirest->delete($url, $headers = array());