The dnscaa package provides a library (not yet) and command-line tool to fetch the DNS CAA (Certification Authority Authorization) records for a hostname.
$ go build cmd/digcaa/digcaa.go
$ ./digcaa www.comodo.com
2 records found
comodo.com. 1199 IN CAA 0 iodef "mailto:sslabuse@comodoca.com"
comodo.com. 1199 IN CAA 0 issue "comodoca.com"
Or use go run to compile-and-run the command:
$ go run cmd/digcaa/digcaa.go www.comodo.com
2 records found
comodo.com. 1199 IN CAA 0 iodef "mailto:sslabuse@comodoca.com"
comodo.com. 1199 IN CAA 0 issue "comodoca.com"