src/Uri/UriGenerator.php
protected function scheme()
    {
        if ($this->cachedHttps === true) {
            $this->https = true;
        }

        return "http" . ($this->https === true ? 's' : '') . "://";
    }
protected function scheme()
    {
        if ($this->cachedHttps === true) {
            $this->https = true;
        }

        return "http" . ($this->https === true ? 's' : '') . "://";
    }
Get url scheme.

@return string