cc := e.clientConfig
	if cc == nil {
		return nil, nil
	}
	var address string
	if cc.URL != nil {
		address = *cc.URL
	}
	var certPool *x509.CertPool
	if len(cc.CABundle) > 0 {
		certPool = x509.NewCertPool()
		certPool.AppendCertsFromPEM(cc.CABundle)
	} else {
		var err error
		certPool, err = x509.SystemCertPool()
		if err != nil {
			return nil, err
		}
	}