Transition guide to Version 4.0

What's new?

All changes can also be reviewed in our official documentation!

Dispatcher

The Dispatcher class has now a cleaner interface and more precise Message filtering. Instead of many methods with long names like Dispatcher.addTelegramMessageHandler(handler), we now only have two of those methods:

addHandler(handler, group=0)

Register a handler. A handler must be an instance of a subclass of telegram.ext.Handler. All handlers are organized in groups, the default group is int(0), but any object can identify a group. Every update will be tested against each handler in each group from first-added to last-added. If the update has been handled in one group, it will not be tested against other handlers in that group. That means an update can only be handled 0 or 1 times per group, but multiple times across all groups.

Parameters:

handler (Handler) – A Handler instance
group (optional[object]) – The group identifier. Default is 0

addErrorHandler(callback)

This method remains unchanged.

So, the addHandler method is accepting an object of a subclass of telegram.ext.Handler. Let's see how that looks in real life:

from telegram.ext import MessageHandler, filters

def text_callback(bot, update):
  print("New text message: " + update.message.text)

dispatcher.addHandler(MessageHandler([filters.TEXT], text_callback))

As you can see here, the MessageHandler class is one of the included Handler subclasses. All that was possible before is still possible, but now more organized and more explicit. Lets take a quick look at another handler class, the RegexHandler:

from telegram.ext import RegexHandler

def name_callback(bot, update, groupdict):
  print("The name of the user is: " + groupdict['name'])

name_regex = r'My name is (?P<name>.*)'
dispatcher.addHandler(RegexHandler(name_regex, text_callback, pass_groupdict=True))

Here you can see the optional argument groupdict passed to the handler callback function. Note that it is necessary to specify this explicitly when creating the Handler object.

Other changes

• You can easily implement your own handlers. Just subclass telegram.ext.handler and take a look at the implementation of the provided handlers.
• Instead of addTelegramInlineHandler there are now InlineHandler, ChosenInlineResultHandler and CallbackQueryHandler
• There is no replacement for addUnknownTelegramCommandHandler. Instead, it is recommended to use RegexHandler(r'/.*', ...) and add it as the last handler
• The UpdateQueue class and context parameters have been removed

Bot API 2.0

Please read the documentation of the Telegram Bot API to learn about all the new things in version 2 of the bot API. This section covers only those changes that are not backwards compatible and not listed in the Recent Changes list.

• new_chat_participant and left_chat_participant of the Message class are now new_chat_member and left_chat_member
• The following parameters on InlineResult and InlineQueryResult objects are removed in favor of InlineMessageContent:

• message_text
• parse_mode
• disable_web_page_preview

• In InlineQueryResultPhoto the parameter mime_type as been removed. JPEG is now required.

The telegram.ext module

The classes Updater, Dispatcher and JobQueue that were previously available for import directly from telegram are now located in telegram.ext.