Adding defaults to your bot

Introduction

As of version 12.4, PTB supports passing default values for arguments such as parse_mode to reduce the need for repetition. For this purpose, the Defaults class was introduced. This makes it possible to set defaults for often used arguments. These are set at the creation of the bot and are immutable.

What can be set to a default

• parse_mode
• disable_notification
• disable_web_page_preview
• allow_sending_without_reply
• timeout
• quote
• tzinfo
• run_async

Example

Here is a show case for setting parse_mode to ParseMode.HTML and tzinfo to pytz.timezone('Europe/Berlin') by default:

import pytz
import datetime as dtm

from telegram import ParseMode
from telegram.ext import Updater, MessageHandler, Filters, Defaults


def job(context):
    chat_id = context.job.context
    local_now = dtm.datetime.now(context.bot.defaults.tzinfo)
    utc_now = dtm.datetime.utcnow()
    text = 'Running job at {} in timezone {}, which equals {} UTC.'.format(
        local_now, context.bot.defaults.tzinfo, utc_now
    )
    context.bot.send_message(chat_id=chat_id, text=text)


def echo(update, context):
    # Send with default parse mode
    update.message.reply_text('<b>{}</b>'.format(update.message.text))
    # Override default parse mode locally
    update.message.reply_text('*{}*'.format(update.message.text), parse_mode=ParseMode.MARKDOWN)
    update.message.reply_text('*{}*'.format(update.message.text), parse_mode=None)

    # Schedule job
    context.job_queue.run_once(job, dtm.datetime.now() + dtm.timedelta(seconds=1),
                               context=update.effective_chat.id)


def main():
    """Instantiate a Defaults object"""
    defaults = Defaults(parse_mode=ParseMode.HTML, tzinfo=pytz.timezone('Europe/Berlin'))

    """Start the bot."""
    updater = Updater("TOKEN", use_context=True, defaults=defaults)

    # Get the dispatcher to register handlers
    dp = updater.dispatcher

    # on non command text message - echo the message on Telegram
    dp.add_handler(MessageHandler(Filters.text & ~Filters.command, echo))

    # Start the Bot
    updater.start_polling()
    updater.idle()


if __name__ == '__main__':
    main()