My first Telegram Bot

devop |

TL;DR This post is kind of a protocol of the initial setup of our Telegram Planets bot. In about 10 minutes, you can send notifications to a chat with curl.

Do not waste time. Get started!

Q: How do I create a bot? Start a chat with ... the Botfather

Creating a new bot is as easy as /newbot and answering some questions.

You'll get a URL like t.me/<your_bot_name>_bot and a token for the HTTP API.

And a hint where to go next: "For a description of the Bot API, see this page: https://core.telegram.org/bots/api"

To give the bot a bit more personality, the Botfather offers some more commands:

command description
/setname change a bot's name
/setdescription change bot description
/setabouttext change bot about info
/setuserpic change bot profile photo
/setcommands change the list of commands

Let's look around in the Telegram Bot API...

All requests have the following format: https://api.telegram.org/bot<token>/METHOD_NAME

Calling getMe reveals basic information about our bot:

$ curl -X GET https://api.telegram.org/bot123456:ABCDEF/getMe
{
    "ok": true,
    "result": {
        "id": 123456,
        "is_bot": true,
        "first_name": "PlanetsFather",
        "username": "planets_father_bot"
    }
}

That was easy...maybe we should getUpdates now?

{
    "ok": true,
    "result": []
}

As promised by the docs another JSON document "which always has a Boolean field ‘ok’". No updates - We have to start a chat with our fresh bot:

hello

and try again getUpdates

{
    "ok": true,
    "result": [
        {
            "update_id": 630248673,
            "message": {
                "message_id": 7,
                "from": {
                    "id": 1234,
                    "is_bot": false,
                    "first_name": "planets",
                    "language_code": "en-US"
                },
                "chat": {
                    "id": 5678,
                    "first_name": "planets",
                    "type": "private"
                },
                "date": 1504891788,
                "text": "Hello"
            }
        }
    ]
}

Now extract the chat id 5678:

$ TELEGRAM_BOT_TOKEN=$(<bot-token.txt)
$ curl -s https://api.telegram.org/bot${TELEGRAM_BOT_TOKEN}/getUpdates | jq -r '.result[0].message.chat.id'
5678

This chatId is where our notifications should go as well.

We are good to go for push notifications to the chat. Let's sendmessage to the chat

$ curl -X POST https://api.telegram.org/bot123456:ABCDEF/sendmessage \
    -H 'content-type: application/json' \
    -d '{ "chat_id": 171765575, "text": "Hello from Planets bot" }'

Nice.

The initial contact with our bot is there. Stay tuned...