code: func CertAuthorityInfo(ca services.CertAuthority) string {
  	var out []string
  	for _, keyPair := range ca.GetTLSKeyPairs() {
  		cert, err := tlsca.ParseCertificatePEM(keyPair.Cert)
  		if err != nil {
  			out = append(out, err.Error())
  		} else {
  			out = append(out, fmt.Sprintf("trust root(%v:%v)", cert.Subject.CommonName, cert.Subject.SerialNumber))
  		}
  	}
  	return fmt.Sprintf("cert authority(state: %v, phase: %v, roots: %v)", ca.GetRotation().State, ca.GetRotation().Phase, strings.Join(out, ", "))
  }
docs: // CertAuthorityInfo returns debugging information about certificate authority