// interface to get back a signed certificate. There is no guarantee that the SAN
// in the request will be returned - server may replace it.
type Client interface {
	CSRSign(csrPEM []byte, certValidTTLInSec int64) ([]string, error)
	Close()
	// Retrieve CA root certs If CA publishes API endpoint for this
	GetRootCertBundle() ([]string, error)
}