Building your First Telegram Bot
Dive deep into developing and deploying your very own Chatbot!
Chatbots are often touted as a revolution in the way users interact with technology and businesses. They have a fairly simple interface compared with traditional apps, as they only require users to chat, and the chatbots are supposed to understand and do whatever the user demands from them, at least in theory.
Chatbots boost operational efficiency and bring cost savings to businesses while offering convenience and added services to internal employees and external customers. They allow companies to easily resolve many types of customer queries and issues while reducing the need for human interaction. With chatbots, a business can scale, personalize, and be proactive all at the same time — which is an important differentiator.
There are a lot of options when it comes to where you can deploy your chatbot, and one of the most common uses are social media platforms, as most people use them on a regular basis. The same can be said of instant messaging apps, though with some limitations.
Telegram is one of the more popular IM platforms today, as it allows you to store messages on the cloud instead of just your device and it boasts good multi-platform support, as you can have Telegram on Android, iOS, Windows, and just about any other platform that can support the web version. Building a chatbot on Telegram is fairly simple and requires few steps that take very little time to complete. The chatbot can be integrated in Telegram groups and channels, and it also works on its own.
Furthermore, we’ll be creating a base bot which could be extended according to your needs!
Our example will involve building a bot using Flask. To complete this, you will need Python 3 installed on your system as well as decent Python coding skills. Also, a good understanding of how apps work would be a good addition, but not a must, as we will be going through most of the stuff we present in detail.
And of course, you also need a Telegram account, which is absolutely free. You can sign up here.
Bringing Your Telegram Bot to Life
To create a chatbot on Telegram, you need to contact the BotFather, which is essentially a bot used to create other bots.
The command you need is /newbot which leads to the following steps to create your bot:
Your bot should have two attributes: a name and a username. The name will show up for your bot, while the username will be used for mentions and sharing.
After choosing your bot name and username — which must end with “bot” — you will get a message containing your access token, and you’ll obviously need to save your access token and username for later, as you will be needing them.
Let’s get to the Code
We will be using Windows in this tutorial.
First, let’s create a virtual environment. It helps isolate your project’s requirements from your global Python environment.
C:\> python -m venv botEnvNow we will have a botEnv/ directory which will contain all the Python libraries we will be using. Go ahead and activate botEnv using the following command:
C:\> botEnv\Scripts\activateThe libraries we need for our bot are:
- Flask: A micro web framework built in Python.
- Python-telegram-bot: A Telegram wrapper in Python.
- Decouple: A Python library to store parameters in .env files.
You can install them in the virtual environment using pip command.
Now let’s browse our project directory.
Telegram-Bot-Base
|--botEnv
|--.env
|--app.pyIn the .env file we will need three variables:
API_KEY = "here goes your access token from BotFather"
BOT_USER_NAME = "the username you entered"
URL = "the hosting link that we will create later" Now let’s go back to our app.py and go through the code step by step:
# import everything
from flask import Flask, request, abort
import telegram
from decouple import config# Fetch variables from .env
API_KEY = config('API_KEY')
USER_NAME = config('BOT_USER_NAME')
URL = config('URL')# initiate bot object with out API key
bot = telegram.Bot(token=API_KEY)
Now we have the bot object which will be used for any action we require the bot to perform.
# start the flask app
app = Flask(__name__)We also need to bind functions to specific routes. In other words, we need to tell Flask what to do when a specific address is called. More detailed info about Flask and routes can be found here.
In our example, the route function responds to a URL which is basically /{token}, and this is the URL Telegram will call to get responses for messages sent to the bot.
@app.route('/{}'.format(API_KEY), methods=['POST'])
def respond():
# retrieve the message in JSON and transform it to Telegram object
update = telegram.Update.de_json(request.get_json(force=True), bot) chat_id = update.message.chat.id
msg_id = update.message.message_id if(update.message.text == None):
return 'ok' # Telegram understands UTF-8, so encode text for its compatibility
text = (update.message.text.encode('utf-8').decode()).lower() # the first time you chat with the bot AKA the welcoming message
if '/start' in text:
bot_welcome = """
Hi, I'm the base bot.\nWanna know more about my source code ??\nHop onto this link: https://github.com/San-B-09/Telegram-Bot-Base
"""
bot.sendMessage(chat_id=chat_id, text=bot_welcome,
reply_to_message_id=msg_id)
elif "hi" in text:
bot_welcome = """
Welcome to Base Bot.
"""
bot.sendMessage(chat_id=chat_id, text=bot_welcome,
reply_to_message_id=msg_id) elif "bye" in text:
bot_welcome = """
Byee!\nHave a productive time!
"""
bot.sendMessage(chat_id=chat_id, text=bot_welcome,
reply_to_message_id=msg_id) return 'ok'
The intuitive way to make this function to work is that we will call it every second, so that it checks whether a new message has arrived, but we won’t be doing that. Instead, we will be using Webhook which provides us a way of letting the bot call our server whenever a message is called, so that we don’t need to make our server suffer in a while loop waiting for a message to come.
So, we will make a function that we ourselves need to call to activate the Webhook of Telegram, basically telling Telegram to call a specific link when a new message arrives. We will call this function one time only, when we first create the bot. If you change the app link, then you will need to run this function again with the new link you have.
The route here can be anything; you’re the one who will call it:
@app.route('/set_webhook', methods=['GET', 'POST'])
def set_webhook():
s = bot.setWebhook('{URL}{HOOK}'.format(URL=URL, HOOK=API_KEY))
if s:
return "webhook setup ok"
else:
return "webhook setup failed"Let’s take a look at the full version of app.py:
That’s the last bit of code you will write in our tutorial. Now we can progress to the last step, launching our app on localhost and then on Heroku.
Launch Our App on localhost
We need a couple of things before we make our app.
Telegram can’t communicate with the localhost directly and hence we’ll need a public URL to communicate with the bot.
Here, we’ll be using ngrok tunneling. ngrok is a free tool that allows us to tunnel from a public URL to our application running locally. You can download ngrok from here.
Activate the ngrok tunnel using following command:
C:\> ngrok http 5000Copy the https URL tunneled to localhost to the URL variable of .env file.
Note: Make sure you append / at the end of URL in .env file.
Now run the app.py file. Then copy the ngrok URL and add to the end of the link /setwebhook so that the address will be something like https://<ngrok code>.ngrok.io/setwebhook. If you see GET /set_webhook 200 OK on ngrok’s terminal, that means you are ready to go!
Launch Our App on Heroku
We need a couple of things before we make our app, including Git installed on your system.
Heroku can’t know what libraries your project uses, so we have to tell it using the requirements.txt file—a common problem is that you misspell requirements, so be careful—to generate the requirements file using pip:
C:\> pip freeze > requirements.txtNote: Make sure requirements.txt is created under appropriate environment.
Now you have your requirements file ready to go.
Now you need the Procfile which tells Heroku where our app starts, so create a Procfile file and add the following:
web: gunicorn app:appNote: Make sure you add guicorn to the requirements.txt separately for Heroku to install guicorn.
From your Heroku dashboard, create a new app. Once you do, it will direct you to the Deploy page. Then, click on open app and copy the domain of the app which will be something like https://appname.herokuapp.com/ and paste it in the URL variable inside .env.
Now, go back to the Deploy tab and proceed with the steps:
Log in to Heroku:
C:\> heroku loginPlease note that this method sometimes gets stuck in waiting for login, if this happens to you, try to log in using:
C:\> heroku login -iInitialize a Git repository in our directory:
C:\> git init
C:\> heroku git:remote -a {heroku-project-name}Deploy the app:
C:\> git add .
C:\> git commit -m "heroku commit"
C:\> git push heroku masterAt this point, you will see the building progress in your terminal. If everything went okay, you will see something like this:
remote: -----> Launching...
remote: Released v6
remote: https://project-name.herokuapp.com/ deployed to Heroku
remote:
remote: Verifying deploy... done.Now go to the app page (the link of the domain you copied before) and add to the end of the link /set_webhook so that the address will be something like https://appname.herokuapp.com/set_webhook. If you see webhook setup ok, that means you are ready to go!
Go talk to your BOT!
Now you can have your bot work the way you want — go ahead, make you customizations and create the next big thing!
I hope you had fun building your first Telegram bot.
