Add implementation of telegram bot (#2889)

* Add implementation of telegram bot

* Fix linting

* More linting issues

* Fixed linting

examples/telegram.js

@@ -0,0 +1,43 @@
+/*
+* This example is a very simple way of connecting to a telegram group
+* For this example you'll need Telegraf installed. This can be done with `npm install telegraf`
+* You need to do this before running this example:
+* - You need to get a telegram bot token from @botfather
+* - You need to get the id of the group you want to use
+*/
+
+if (process.argv.length < 6 || process.argv.length > 8) {
+  console.log('Usage : node telegram.js <telegram bot token> <group id> <host> <port> [<name>] [<password>]')
+  process.exit(1)
+}
+
+// Load Telegraf
+const { Telegraf } = require('telegraf')
+const telegram = new Telegraf(process.argv[2])
+
+// Load mineflayer
+const mineflayer = require('mineflayer')
+const bot = mineflayer.createBot({
+  host: process.argv[4],
+  port: parseInt(process.argv[5]),
+  username: process.argv[6] || 'telegram',
+  password: process.argv[7]
+})
+
+telegram.on('text', async (ctx) => {
+  // check if message was reveived from chosen group
+  if (ctx.update.message.chat.id.toString() === process.argv[3]) {
+    // send message to mc server
+    bot.chat(`${ctx.update.message.from.first_name} ${ctx.update.message.from.last_name}: ${ctx.update.message.text}`)
+  }
+})
+
+// Redirect in-game messages to telegram group
+bot.on('chat', (username, message) => {
+  // Ignore messages from the bot itself
+  if (username === bot.username) return
+  telegram.telegram.sendMessage(process.argv[3], username + ': ' + message)
+})
+
+// Login telegram bot
+telegram.launch()