I'm not sure that we need to see output in the logs if things are ok. If we don't want to see something in the logs on success, we'll want to change the code around to:

```ruby
if !verify(SITE_CONFIG['mailgun_api_key'],params['token'],params['timestamp'],params['signature'])
  Rails.logger.info "Cannot verify Mailgun signature"
  render_failure "Unacceptable signature", 406
  return
end
```