Go SEPA provides tools and utilities for generating SEPA-XML Files and validating the input.
go get github.com/nirnanaaa/go-sepa
Verifying creditor identifier (ci):
ci := sepa.NewCreditorIdentifier("DE98ZZZ09999999999")
sanitized, err := ci.Validate()
Verifying IBAN (iban):
iban := sepa.NewIBAN("DE21700519950000007229")
sanitized, err := iban.Validate()