Web form with telegram bot

app.py

## This code makes a web form to send messages to telegram users
## pip install aiogram quart flask-wtf
## QUART_APP=app:app quart run

import logging
logger = logging.getLogger(__name__)

import asyncio, secrets
from aiogram import (
    Bot,
    Dispatcher,
)
from quart import (
    Quart,
    current_app,
    flask_patch,
    jsonify,
    request,
)
from flask_wtf import FlaskForm
from wtforms import (
    StringField,
    SubmitField,
    TextAreaField,
)

token = "123456:ABC-DEF1234ghIkl-zyx57W2v1u123ew11"
bot = Bot(token = token)
dispatcher = Dispatcher(bot)
app = Quart(__name__)
app.secret_key = secrets.token_urlsafe(32)

@app.before_serving
async def before_serving():
    ## There are other ways to do this, I do it like this because I then
    ## can access the dispatcher object with current_app.dispatcher
    setattr(current_app, 'dispatcher', dispatcher)
    loop = asyncio.get_event_loop()
    ## You can start the webhooks here instead
    loop.create_task(dispatcher.start_polling(
        reset_webhook = True,
        timeout = 20,
        relax = 0.1,
        fast = True,
        allowed_updates = None,
    ))

@app.after_serving
async def after_serving():
    await dispatcher.storage.close()
    await dispatcher.storage.wait_closed()

class SendMessageForm(FlaskForm):
    chat_id_field = StringField('select chat', default = 1)
    text_field = TextAreaField('message', default = u"Nevermind")
    submit = SubmitField('send')

@app.route('/', methods = ['GET', 'POST'])
async def send_message():
    message = None
    form = SendMessageForm(formdata = await request.form)
    if request.method == "POST":
        try:
            await dispatcher.bot.send_message(
                chat_id = int(form['chat_id_field'].data),
                text = str(form['text_field'].data),
            )
        except Exception as exception:
            return jsonify(repr(exception))
            raise
    return f"""
<form action="" method="post">
<p>
{form.chat_id_field.label}<br>
{form.chat_id_field(size=5, placeholder = form.chat_id_field.description)}<br>
</p>
<p>{form.text_field.label}<br />{form.text_field}</p>
<p>{form.submit}</p>
</form>
"""

app.run()