Telegram: 1. Basic

The following tutorial shows how to run a regular DFF script in Telegram. It asks users for the ‘/start’ command and then loops in one place.

Here, PollingTelegramInterface class and telebot library are used for accessing telegram API in polling mode.

Telegram API token is required to access telegram API.

# installing dependencies
%pip install -q dff[telegram]

Note: you may need to restart the kernel to use updated packages.

import os

from dff.script import conditions as cnd
from dff.script import labels as lbl
from dff.script import RESPONSE, TRANSITIONS, Message
from dff.messengers.telegram import PollingTelegramInterface
from dff.pipeline import Pipeline
from dff.utils.testing.common import is_interactive_mode

In order to integrate your script with Telegram, you need an instance of TelegramMessenger class and one of the following interfaces: PollingMessengerInterface or WebhookMessengerInterface.

TelegramMessenger encapsulates the bot logic. Like Telebot, TelegramMessenger only requires a token to run. However, all parameters from the Telebot class can be passed as keyword arguments.

The two interfaces connect the bot to Telegram. They can be passed directly to the DFF Pipeline instance.

script = {
    "greeting_flow": {
        "start_node": {
            TRANSITIONS: {"greeting_node": cnd.exact_match(Message("/start"))},
        },
        "greeting_node": {
            RESPONSE: Message("Hi"),
            TRANSITIONS: {lbl.repeat(): cnd.true()},
        },
        "fallback_node": {
            RESPONSE: Message("Please, repeat the request"),
            TRANSITIONS: {"greeting_node": cnd.exact_match(Message("/start"))},
        },
    }
}

# this variable is only for testing
happy_path = (
    (Message("/start"), Message("Hi")),
    (Message("Hi"), Message("Hi")),
    (Message("Bye"), Message("Hi")),
)

interface = PollingTelegramInterface(token=os.environ["TG_BOT_TOKEN"])

pipeline = Pipeline.from_script(
    script=script,
    start_label=("greeting_flow", "start_node"),
    fallback_label=("greeting_flow", "fallback_node"),
    messenger_interface=interface,
    # The interface can be passed as a pipeline argument.
)


def main():
    pipeline.run()


if __name__ == "__main__" and is_interactive_mode():
    # prevent run during doc building
    main()