punycode.go (1460B)
1 // GoToSocial 2 // Copyright (C) GoToSocial Authors admin@gotosocial.org 3 // SPDX-License-Identifier: AGPL-3.0-or-later 4 // 5 // This program is free software: you can redistribute it and/or modify 6 // it under the terms of the GNU Affero General Public License as published by 7 // the Free Software Foundation, either version 3 of the License, or 8 // (at your option) any later version. 9 // 10 // This program is distributed in the hope that it will be useful, 11 // but WITHOUT ANY WARRANTY; without even the implied warranty of 12 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 // GNU Affero General Public License for more details. 14 // 15 // You should have received a copy of the GNU Affero General Public License 16 // along with this program. If not, see <http://www.gnu.org/licenses/>. 17 18 package util 19 20 import ( 21 "strings" 22 23 "golang.org/x/net/idna" 24 ) 25 26 // Punify converts the given domain to lowercase 27 // then to punycode (for international domain names). 28 // 29 // Returns the resulting domain or an error if the 30 // punycode conversion fails. 31 func Punify(domain string) (string, error) { 32 domain = strings.ToLower(domain) 33 return idna.ToASCII(domain) 34 } 35 36 // DePunify converts the given punycode string 37 // to its original unicode representation (lowercased). 38 // Noop if the domain is (already) not puny. 39 // 40 // Returns an error if conversion fails. 41 func DePunify(domain string) (string, error) { 42 out, err := idna.ToUnicode(domain) 43 return strings.ToLower(out), err 44 }