// GoToSocial // Copyright (C) GoToSocial Authors admin@gotosocial.org // SPDX-License-Identifier: AGPL-3.0-or-later // // This program is free software: you can redistribute it and/or modify // it under the terms of the GNU Affero General Public License as published by // the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU Affero General Public License for more details. // // You should have received a copy of the GNU Affero General Public License // along with this program. If not, see . package regexes import ( "bytes" "regexp" "sync" "mvdan.cc/xurls/v2" ) const ( users = "users" actors = "actors" statuses = "statuses" inbox = "inbox" outbox = "outbox" followers = "followers" following = "following" liked = "liked" publicKey = "main-key" follow = "follow" blocks = "blocks" reports = "reports" schemes = `(http|https)://` // Allowed URI protocols for parsing links in text. alphaNumeric = `\p{L}\p{M}*|\p{N}` // A single number or script character in any language, including chars with accents. usernameGrp = `(?:` + alphaNumeric + `|\.|\-|\_)` // Non-capturing group that matches against a single valid username character. domainGrp = `(?:` + alphaNumeric + `|\.|\-|\:)` // Non-capturing group that matches against a single valid domain character. mentionName = `^@(` + usernameGrp + `+)(?:@(` + domainGrp + `+))?$` // Extract parts of one mention, maybe including domain. mentionFinder = `(?:^|\s)(@` + usernameGrp + `+(?:@` + domainGrp + `+)?)` // Extract all mentions from a text, each mention may include domain. emojiShortcode = `\w{2,30}` // Pattern for emoji shortcodes. maximumEmojiShortcodeLength = 30 emojiFinder = `(?:\b)?:(` + emojiShortcode + `):(?:\b)?` // Extract all emoji shortcodes from a text. emojiValidator = `^` + emojiShortcode + `$` // Validate a single emoji shortcode. usernameStrict = `^[a-z0-9_]{1,64}$` // Pattern for usernames on THIS instance. maximumUsernameLength = 64 usernameRelaxed = `[a-z0-9_\.]{1,}` // Relaxed version of username that can match instance accounts too. misskeyReportNotesFinder = `(?m)(?:^Note: ((?:http|https):\/\/.*)$)` // Extract reported Note URIs from the text of a Misskey report/flag. ulid = `[0123456789ABCDEFGHJKMNPQRSTVWXYZ]{26}` // Pattern for ULID. ulidValidate = `^` + ulid + `$` // Validate one ULID. /* Path parts / capture. */ userPathPrefix = `^/?` + users + `/(` + usernameRelaxed + `)` userPath = userPathPrefix + `$` userWebPathPrefix = `^/?` + `@(` + usernameRelaxed + `)` userWebPath = userWebPathPrefix + `$` publicKeyPath = userPathPrefix + `/` + publicKey + `$` inboxPath = userPathPrefix + `/` + inbox + `$` outboxPath = userPathPrefix + `/` + outbox + `$` followersPath = userPathPrefix + `/` + followers + `$` followingPath = userPathPrefix + `/` + following + `$` likedPath = userPathPrefix + `/` + liked + `$` followPath = userPathPrefix + `/` + follow + `/(` + ulid + `)$` likePath = userPathPrefix + `/` + liked + `/(` + ulid + `)$` statusesPath = userPathPrefix + `/` + statuses + `/(` + ulid + `)$` blockPath = userPathPrefix + `/` + blocks + `/(` + ulid + `)$` reportPath = `^/?` + reports + `/(` + ulid + `)$` filePath = `^/?(` + ulid + `)/([a-z]+)/([a-z]+)/(` + ulid + `)\.([a-z0-9]+)$` ) var ( // LinkScheme captures http/https schemes in URLs. LinkScheme = func() *regexp.Regexp { rgx, err := xurls.StrictMatchingScheme(schemes) if err != nil { panic(err) } return rgx }() // MentionName captures the username and domain part from // a mention string such as @whatever_user@example.org, // returning whatever_user and example.org (without the @ symbols). // Will also work for characters with umlauts and other accents. // See: https://regex101.com/r/9tjNUy/1 for explanation and examples. MentionName = regexp.MustCompile(mentionName) // MentionFinder extracts whole mentions from a piece of text. MentionFinder = regexp.MustCompile(mentionFinder) // EmojiValidator validates an emoji shortcode. EmojiValidator = regexp.MustCompile(emojiValidator) // EmojiFinder extracts emoji strings from a piece of text. // See: https://regex101.com/r/478XGM/1 EmojiFinder = regexp.MustCompile(emojiFinder) // Username can be used to validate usernames of new signups on this instance. Username = regexp.MustCompile(usernameStrict) // MisskeyReportNotes captures a list of Note URIs from report content created by Misskey. // See: https://regex101.com/r/EnTOBV/1 MisskeyReportNotes = regexp.MustCompile(misskeyReportNotesFinder) // UserPath validates and captures the username part from eg /users/example_username. UserPath = regexp.MustCompile(userPath) // UserWebPath validates and captures the username part from eg /@example_username. UserWebPath = regexp.MustCompile(userWebPath) // PublicKeyPath parses a path that validates and captures the username part from eg /users/example_username/main-key PublicKeyPath = regexp.MustCompile(publicKeyPath) // InboxPath parses a path that validates and captures the username part from eg /users/example_username/inbox InboxPath = regexp.MustCompile(inboxPath) // OutboxPath parses a path that validates and captures the username part from eg /users/example_username/outbox OutboxPath = regexp.MustCompile(outboxPath) // FollowersPath parses a path that validates and captures the username part from eg /users/example_username/followers FollowersPath = regexp.MustCompile(followersPath) // FollowingPath parses a path that validates and captures the username part from eg /users/example_username/following FollowingPath = regexp.MustCompile(followingPath) // LikedPath parses a path that validates and captures the username part from eg /users/example_username/liked LikedPath = regexp.MustCompile(likedPath) // ULID parses and validate a ULID. ULID = regexp.MustCompile(ulidValidate) // FollowPath parses a path that validates and captures the username part and the ulid part // from eg /users/example_username/follow/01F7XT5JZW1WMVSW1KADS8PVDH FollowPath = regexp.MustCompile(followPath) // LikePath parses a path that validates and captures the username part and the ulid part // from eg /users/example_username/liked/01F7XT5JZW1WMVSW1KADS8PVDH LikePath = regexp.MustCompile(likePath) // StatusesPath parses a path that validates and captures the username part and the ulid part // from eg /users/example_username/statuses/01F7XT5JZW1WMVSW1KADS8PVDH // The regex can be played with here: https://regex101.com/r/G9zuxQ/1 StatusesPath = regexp.MustCompile(statusesPath) // BlockPath parses a path that validates and captures the username part and the ulid part // from eg /users/example_username/blocks/01F7XT5JZW1WMVSW1KADS8PVDH BlockPath = regexp.MustCompile(blockPath) // ReportPath parses a path that validates and captures the ulid part // from eg /reports/01GP3AWY4CRDVRNZKW0TEAMB5R ReportPath = regexp.MustCompile(reportPath) // FilePath parses a file storage path of the form [ACCOUNT_ID]/[MEDIA_TYPE]/[MEDIA_SIZE]/[FILE_NAME] // eg 01F8MH1H7YV1Z7D2C8K2730QBF/attachment/small/01F8MH8RMYQ6MSNY3JM2XT1CQ5.jpeg // It captures the account id, media type, media size, file name, and file extension, eg // `01F8MH1H7YV1Z7D2C8K2730QBF`, `attachment`, `small`, `01F8MH8RMYQ6MSNY3JM2XT1CQ5`, `jpeg`. FilePath = regexp.MustCompile(filePath) ) // bufpool is a memory pool of byte buffers for use in our regex utility functions. var bufpool = sync.Pool{ New: func() any { buf := bytes.NewBuffer(make([]byte, 0, 512)) return buf }, } // ReplaceAllStringFunc will call through to .ReplaceAllStringFunc in the provided regex, but provide you a clean byte buffer for optimized string writes. func ReplaceAllStringFunc(rgx *regexp.Regexp, src string, repl func(match string, buf *bytes.Buffer) string) string { buf := bufpool.Get().(*bytes.Buffer) //nolint defer bufpool.Put(buf) return rgx.ReplaceAllStringFunc(src, func(match string) string { buf.Reset() // reset use return repl(match, buf) }) }