go get github.com/luanruisong/ga-decoder
func main(){
url := `otpauth-migration://offline?data={data str}`
res, err := ga_decoder.DecoderMigrationPayload(url)
if err != nil {
panic(err)
}
fmt.Println(res)
for _, v := range res.OtpParameters {
fmt.Println(ga_decoder.DecodeSecret(v.Secret))
}
}