function update_user_avatar()
{
$user_service = new User_service();
$user_model = new User_model();
$user_model->set_user_avatar($this->input->post('user_avatar', TRUE));
$user_model->set_user_id($this->input->post('user_id', TRUE));
$result = $user_service->update_user_avatar($user_model);
//update session profile pic into new pic
$this->session->set_userdata('USER_PROPIC', $this->input->post('user_avatar', TRUE));
echo $result;
}