public function createToken($endpoint, $region, $username)
    {
        $uri = new Uri($endpoint);
        $uri = $uri->withPath('/');
        $uri = $uri->withQuery('Action=connect&DBUser=' . $username);

        $request = new Request('GET', $uri);
        $signer = new SignatureV4('rds-db', $region);
        $provider = $this->credentialProvider;

        $url = (string) $signer->presign(
            $request,
            $provider()->wait(),
            '+15 minutes'
        )->getUri();

        // Remove 2 extra slash from the presigned url result
        return substr($url, 2);
    }