Building a serverless Telegram bot

Mon, 03 Sep 2018 18:48:00 +0000

With the arrival of FaaS and all the serverless infrastructure providers (AWS, Google Cloud, Azure, etc) now is easy to deploy our own Telegram bot.

A Webhook-based bot it’s the perfect use case for serverless computing, using for example Google Cloud Functions we’ll have all these advantages:

Our function will be associated to a public endpoint (IPv4 and IPv6) over HTTPS (using a valid certificate provided by Google)
Pay only for function invocations and its compute resources consumption, so it could be cheaper than paying for a server powered on all the time
No server management
Scales automatically

Requirements

Before start building your bot you’ll need to:

Register a new bot following these instructions core.telegram.org/bots in order to get an API token
Using a Google Cloud account, register a new project, enable the Cloud Functions API and install the Cloud SDK following the official quickstart

Code

In a few lines of Python you can code a simple echo bot that will reply with the same message that it receives:

 text
 text
 
# main.py
import os
import telegram

def webhook(request):
 bot = telegram.Bot(token=os.environ["TELEGRAM_TOKEN"])
 if request.method == "POST":
 update = telegram.Update.de_json(request.get_json(force=True), bot)
 chat_id = update.message.chat.id
 # Reply with the same message
 bot.sendMessage(chat_id=chat_id, text=update.message.text)
 return "ok"

The only dependency needed is the amazing python-telegram-bot library:

 text
 text
 
# requirements.txt 
python-telegram-bot==11.1.0

Automation on Pablo Seminario

Building a serverless Telegram bot

Requirements

Code