[IMPROVE] Slack import: Parse channel and user mentions (#17637)

* Treating channel mentions similarly to user mentions

* First iteration, links not clickable client-side yet.

* Made channel links clickable. #general import not working yet, as well as channel names with umlauts

* Finished implementation of clickable links. Had to add dname field to channel objects and message parser to make matching by parser possible without changing display of channels by using fname.

Co-authored-by: pierre-lehnen-rc <55164754+pierre-lehnen-rc@users.noreply.github.com>

app/importer-slack/server/importer.js

@@ -16,6 +16,7 @@ import { Users, Rooms, Messages } from '../../models';
 import { insertMessage, createDirectRoom } from '../../lib';
 import { getValidRoomName } from '../../utils';
 import { settings } from '../../settings/server';
+import { MentionsParser } from '../../mentions/lib/MentionsParser';
 
 export class SlackImporter extends Base {
 	constructor(info, importRecord) {
@@ -242,6 +243,48 @@ export class SlackImporter extends Base {
 		});
 	}
 
+	parseMentions(message) {
+		const mentionsParser = new MentionsParser({
+			pattern: () => settings.get('UTF8_Names_Validation'),
+			useRealName: () => settings.get('UI_Use_Real_Name'),
+			me: () => 'me',
+		});
+
+		if (!message.mentions) {
+			message.mentions = [];
+		}
+		const users = mentionsParser.getUserMentions(message.msg);
+		users.forEach((user_id, index, arr) => {
+			const user = user_id.slice(1, user_id.length);
+			try {
+				if (user === 'all' || user === 'here') {
+					arr[index] = user;
+				} else {
+					arr[index] = Users.findOneByUsernameIgnoringCase(user);
+				}
+			} catch (e) {
+				this.logger.warn(`Failed to import user mention with name: ${ user }`);
+			}
+		});
+		message.mentions.push(...users);
+
+		if (!message.channels) {
+			message.channels = [];
+		}
+		const channels = mentionsParser.getChannelMentions(message.msg);
+		channels.forEach((channel_name, index, arr) => {
+			const chan = channel_name.slice(1, channel_name.length);
+			try {
+				const slackChannel = this.getSlackChannelFromName(chan);
+				arr[index] = Rooms.findOneById(slackChannel.rocketId);
+				arr[index].dname = chan; // Have to store name to display so parser can match it
+			} catch (e) {
+				this.logger.warn(`Failed to import channel mention with name: ${ chan }`);
+			}
+		});
+		message.channels.push(...channels);
+	}
+
 	processMessageSubType(message, room, msgDataDefaults, missedTypes) {
 		const ignoreTypes = { bot_add: true, file_comment: true, file_mention: true };
 
@@ -274,6 +317,7 @@ export class SlackImporter extends Base {
 					...msgDataDefaults,
 					msg: `_${ this.convertSlackMessageToRocketChat(message.text) }_`,
 				};
+				this.parseMentions(msgObj);
 				insertMessage(rocketUser, msgObj, room, this._anyExistingSlackMessage);
 				break;
 			}
@@ -304,6 +348,7 @@ export class SlackImporter extends Base {
 				if (message.icons) {
 					msgObj.emoji = message.icons.emoji;
 				}
+				this.parseMentions(msgObj);
 				insertMessage(botUser, msgObj, room, this._anyExistingSlackMessage);
 				break;
 			}
@@ -457,6 +502,7 @@ export class SlackImporter extends Base {
 						}
 					}
 
+					this.parseMentions(msgObj);
 					try {
 						insertMessage(this.getRocketUserFromUserId(message.user), msgObj, room, this._anyExistingSlackMessage);
 					} catch (e) {
@@ -970,6 +1016,7 @@ export class SlackImporter extends Base {
 			message = message.replace(/:uk:/g, ':gb:');
 			message = message.replace(/<(http[s]?:[^>|]*)>/g, '$1');
 			message = message.replace(/<(http[s]?:[^|]*)\|([^>]*)>/g, '[$2]($1)');
+			message = message.replace(/<#([^|]*)\|([^>]*)>/g, '#$2');
 
 			for (const userReplace of Array.from(this.userTags)) {
 				message = message.replace(userReplace.slack, userReplace.rocket);

app/mentions/lib/MentionsParser.js

@@ -79,11 +79,11 @@ export class MentionsParser {
 	replaceChannels = (msg, { temp, channels }) => msg
 		.replace(/'/g, '\'')
 		.replace(this.channelMentionRegex, (match, prefix, mention) => {
-			if (!temp && !(channels && channels.find((c) => c.name === mention))) {
+			if (!temp && !(channels && channels.find(function(c) { return c.dname ? c.dname === mention : c.name === mention; }))) {
 				return match;
 			}
 
-			const channel = channels && channels.find(({ name }) => name === mention);
+			const channel = channels && channels.find(function({ name, dname }) { return dname ? dname === mention : name === mention; });
 			const reference = channel ? channel._id : mention;
 			return `${ prefix }<a class="mention-link mention-link--room" data-channel="${ reference }">${ `#${ mention }` }</a>`;
 		})