Cloudflare Workers Telegram Bot

This past week I spent rewriting

`cf-workers-telegram-bot`.

Here I'm going to show you the newly updated API that anyone can use to run a

Telegram Bot on Cloudflare Workers or any other serverless platform.

Project Setup

First you need to set up a new Cloudflare Workers project using wrangler.

npm create cloudflare@latest

This will prompt you for a project name first. Choose a name for your new

project or use the default.

Next you'll be prompted for the type of application you want to deploy. You

should choose a "Hello World" Worker.

After that you'll be asked a few more questions, like if you want to use

TypeScript, and Git (optional, but recommended). You don't need to deploy just

yet.

Adding Your Bot Token

Next you can add the token you get from @BotFather on Telegram as a secret so

you don't have to keep it in the code.

npx wrangler secret put TOKEN

Once you've created your project and created your secret you'll want to install

the cf-workers-telegram-bot library to start coding.

cd your-new-project
npm i @codebam/cf-workers-telegram-bot

This will give you access to my TelegramBot class for creating a Telegram Bot.

Writing the Bot

To get started you can open src/index.ts in your favorite editor such as

vscode or vim. Then you can import like this.

import TelegramBot, { TelegramExecutionContext } from '@codebam/cf-workers-telegram-bot';

Then you can simply write your bot like this.

export default {
  async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
    const bot = new TelegramBot(env.TOKEN);
    await bot.on('start', async function (context: TelegramExecutionContext) {
      switch (context.update_type) {
	case 'message':
	  await context.reply('Hello from Cloudflare workers');
	  break;

	default:
	  break;
      }
    }).handle(request.clone());
    return new Response('ok');
  },
};

Deployment and Webhook

Now you're ready to deploy.

npx wrangler deploy

You can set your webhook by going to the URL you've been given plus your token and ?command=set.

Like this. https://telegram-bot.username.workers.dev/YOURTOKENHERE?command=set

Now when you send your bot a message on Telegram it should respond with Hello from Cloudflare workers.

Starter Template

If you've got this far and you don't want to code it all by yourself, you can

fork my repository here to get

started with a working copy.