provider/aws.go
func canonicalHostedZone(hostname string) string {
	for suffix, zone := range canonicalHostedZones {
		if strings.HasSuffix(hostname, suffix) {
			return zone
		}
	}

	return ""
}
func canonicalHostedZone(hostname string) string {
	for suffix, zone := range canonicalHostedZones {
		if strings.HasSuffix(hostname, suffix) {
			return zone
		}
	}

	return ""
}
// canonicalHostedZone returns the matching canonical zone for a given hostname.