Create middlewares/logPresence (#104)

example.config.js

@@ -1,7 +1,5 @@
 'use strict';
 
-/* eslint-disable sort-keys */
-
 /*
  * Create `config.js` by running `cp example.config.js config.js`
  * in the project folder, then edit it.
@@ -36,6 +34,13 @@ module.exports = {
 
 	chats: {
 
+		/**
+		 * @type {(number | false)}
+		 * Chat to send member join/leave notifications to.
+		 * Pass false to disable this feature.
+		 */
+		presenceLog: false,
+
 		/**
 		 * @type {(number | false)}
 		 * Chat to send report notifications to.

handlers/middlewares/index.js

@@ -1,6 +1,5 @@
 'use strict';
 
-const millisecond = require('millisecond');
 const { Composer } = require('telegraf');
 
 const composer = new Composer();
@@ -18,6 +17,7 @@ const removeChannelForwardsHandler = require('./removeChannelForwards');
 const removeCommandsHandler = require('./removeCommands');
 const syncStatusHandler = require('./syncStatus');
 const updateUserDataHandler = require('./updateUserData');
+const presenceLogHandler = require('./logPresence');
 const updateGroupTitleHandler = require('./updateGroupTitle');
 
 composer.on('new_chat_members', addedToGroupHandler);
@@ -32,9 +32,8 @@ composer.on('new_chat_title', updateGroupTitleHandler);
 composer.on('text', removeCommandsHandler);
 composer.on(
 	[ 'new_chat_members', 'left_chat_member' ],
-	deleteJoinsAfter === false
-		? Composer.passThru()
-		: deleteAfter(millisecond(deleteJoinsAfter))
+	deleteAfter(deleteJoinsAfter),
+	presenceLogHandler,
 );
 
 module.exports = composer;

handlers/middlewares/logPresence.js

@@ -0,0 +1,28 @@
+'use strict';
+
+const { chats = {} } = require('../../config');
+
+function getUsername(user) {
+	let str = user.first_name;
+	if (user.last_name) str += ' ' + user.last_name;
+	if (user.username) str += ' (@' + user.username + ')';
+	return str;
+}
+function log(ctx, next) {
+	if (!chats.presenceLog) return next();
+	if (ctx.updateSubTypes[0] === 'new_chat_members') {
+		ctx.telegram.sendMessage(
+			chats.presenceLog,
+			ctx.message.new_chat_members.map(getUsername).join(', ') +
+				' #joined ' + ctx.chat.title
+		);
+	} else if (ctx.updateSubTypes[0] === 'left_chat_member') {
+		ctx.telegram.sendMessage(
+			chats.presenceLog,
+			getUsername(ctx.message.left_chat_member) +
+				' #left ' + ctx.chat.title
+		);
+	}
+	return next();
+}
+module.exports = log;

utils/tg.js

@@ -40,7 +40,9 @@ const displayUser = user =>
  * @returns {undefined}
  */
 const deleteAfter = ms => (ctx, next) => {
-	setTimeout(ctx.deleteMessage, ms);
+	if (ms !== false) {
+		setTimeout(ctx.deleteMessage, millisecond(ms));
+	}
 	next();
 };