From 1630e3748d05fe4facb9acd462c9eb8669afdbca Mon Sep 17 00:00:00 2001
From: Diego Sampaio <chinello@gmail.com>
Date: Thu, 21 Sep 2023 15:39:15 -0300
Subject: [PATCH] move badwords to its own file

---
 .../services/messages/hooks/badwords.ts       | 26 ++++++
 .../server/services/messages/service.ts       | 82 ++++++++-----------
 2 files changed, 58 insertions(+), 50 deletions(-)
 create mode 100644 apps/meteor/server/services/messages/hooks/badwords.ts

diff --git a/apps/meteor/server/services/messages/hooks/badwords.ts b/apps/meteor/server/services/messages/hooks/badwords.ts
new file mode 100644
index 000000000000..17641d8f9c7f
--- /dev/null
+++ b/apps/meteor/server/services/messages/hooks/badwords.ts
@@ -0,0 +1,26 @@
+export async function configureBadWords(badWordsList?: string, goodWordsList?: string) {
+	const { default: Filter } = await import('bad-words');
+
+	const options = {
+		list:
+			badWordsList
+				?.split(',')
+				.map((word) => word.trim())
+				.filter(Boolean) || [],
+		// library definition does not allow optional definition
+		exclude: undefined,
+		splitRegex: undefined,
+		placeHolder: undefined,
+		regex: undefined,
+		replaceRegex: undefined,
+		emptyList: undefined,
+	};
+
+	const badWords = new Filter(options);
+
+	if (goodWordsList?.length) {
+		badWords.removeWords(...goodWordsList.split(',').map((word) => word.trim()));
+	}
+
+	return badWords;
+}
diff --git a/apps/meteor/server/services/messages/service.ts b/apps/meteor/server/services/messages/service.ts
index 8afd4de0fa2c..9f0426de9d15 100644
--- a/apps/meteor/server/services/messages/service.ts
+++ b/apps/meteor/server/services/messages/service.ts
@@ -2,7 +2,7 @@ import type { IMessageService } from '@rocket.chat/core-services';
 import { ServiceClassInternal } from '@rocket.chat/core-services';
 import type { IMessage, MessageTypesValues, IUser, IRoom } from '@rocket.chat/core-typings';
 import { Messages } from '@rocket.chat/models';
-import Filter from 'bad-words';
+import type BadWordsFilter from 'bad-words';
 
 import { deleteMessage } from '../../../app/lib/server/functions/deleteMessage';
 import { sendMessage } from '../../../app/lib/server/functions/sendMessage';
@@ -10,47 +10,33 @@ import { updateMessage } from '../../../app/lib/server/functions/updateMessage';
 import { executeSendMessage } from '../../../app/lib/server/methods/sendMessage';
 import { executeSetReaction } from '../../../app/reactions/server/setReaction';
 import { settings } from '../../../app/settings/server';
+import { configureBadWords } from './hooks/badwords';
 
-class BadWordsFilter {
-	private static instance: Filter;
+export class MessageService extends ServiceClassInternal implements IMessageService {
+	protected name = 'message';
 
-	private constructor() {
-		// no op
-	}
+	private badWordsFilter?: BadWordsFilter;
 
-	static configure(badWordsList?: string, goodWordsList?: string) {
-		const options = {
-			list:
-				badWordsList
-					?.split(',')
-					.map((word) => word.trim())
-					.filter(Boolean) || [],
-			// library definition does not allow optional definition
-			exclude: undefined,
-			splitRegex: undefined,
-			placeHolder: undefined,
-			regex: undefined,
-			replaceRegex: undefined,
-			emptyList: undefined,
-		};
-
-		BadWordsFilter.instance = new Filter(options);
-
-		if (goodWordsList?.length) {
-			BadWordsFilter.instance.removeWords(...goodWordsList.split(',').map((word) => word.trim()));
-		}
+	async created() {
+		await this.configureBadWords();
 	}
 
-	static getFilter() {
-		if (!BadWordsFilter.instance) {
-			throw new Error('BadWordsFilter not configured');
+	private async configureBadWords() {
+		if (!this.isBadWordsFilterEnabled()) {
+			return;
 		}
-		return BadWordsFilter.instance;
-	}
-}
 
-export class MessageService extends ServiceClassInternal implements IMessageService {
-	protected name = 'message';
+		settings.watchMultiple(
+			['Message_AllowBadWordsFilter', 'Message_BadWordsFilterList', 'Message_BadWordsWhitelist'],
+			async ([enabled, badWordsList, whiteList]) => {
+				if (!enabled) {
+					this.badWordsFilter = undefined;
+					return;
+				}
+				this.badWordsFilter = await configureBadWords(badWordsList as string, whiteList as string);
+			},
+		);
+	}
 
 	async sendMessage({ fromId, rid, msg }: { fromId: string; rid: string; msg: string }): Promise<IMessage> {
 		return executeSendMessage(fromId, { rid, msg });
@@ -104,32 +90,28 @@ export class MessageService extends ServiceClassInternal implements IMessageServ
 		room: IRoom;
 		user: Pick<IUser, '_id' | 'username' | 'name'>;
 	}): Promise<IMessage> {
-		// TODO move BadWordsFilter.configure to constructor and watch for settings changes
-		const badWordsList = settings.get<string>('Message_BadWordsFilterList');
-		const whiteList = settings.get<string>('Message_BadWordsWhitelist');
-		BadWordsFilter.configure(badWordsList, whiteList);
-
-		// TODO looks like this one was not being used
+		// TODO looks like this one was not being used (so I'll left it commented)
 		// await this.joinDiscussionOnMessage({ message, room, user });
 
-		message = await this.filterBadWords(message);
+		// conditionals here should be fast, so they won't add up for each message
+		if (this.isBadWordsFilterEnabled()) {
+			message = await this.filterBadWords(message);
+		}
 
 		return message;
 	}
 
-	private async filterBadWords(message: IMessage): Promise<IMessage> {
-		if (!message.msg) {
-			return message;
-		}
+	private isBadWordsFilterEnabled() {
+		return !!settings.get('Message_AllowBadWordsFilter');
+	}
 
-		if (!settings.get('Message_AllowBadWordsFilter')) {
+	private async filterBadWords(message: IMessage): Promise<IMessage> {
+		if (!message.msg || !this.badWordsFilter) {
 			return message;
 		}
 
 		try {
-			const filter = BadWordsFilter.getFilter();
-
-			message.msg = filter.clean(message.msg);
+			message.msg = this.badWordsFilter.clean(message.msg);
 		} catch (error) {
 			// ignore
 		}