#!/usr/bin/env python # # A library that provides a Python interface to the Telegram Bot API # Copyright (C) 2015-2018 # Leandro Toledo de Souza # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU Lesser Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU Lesser Public License for more details. # # You should have received a copy of the GNU Lesser Public License # along with this program. If not, see [http://www.gnu.org/licenses/]. """This module contains the class Updater, which tries to make creating Telegram bots intuitive.""" import logging import ssl from threading import Thread, Lock, current_thread, Event from time import sleep from signal import signal, SIGINT, SIGTERM, SIGABRT from queue import Queue from telegram import Bot, TelegramError from telegram.ext import Dispatcher, JobQueue from telegram.error import Unauthorized, InvalidToken, RetryAfter, TimedOut from telegram.utils.helpers import get_signal_name from telegram.utils.request import Request from telegram.utils.webhookhandler import (WebhookServer, WebhookAppClass) logging.getLogger(__name__).addHandler(logging.NullHandler()) class Updater(object): """ This class, which employs the :class:`telegram.ext.Dispatcher`, provides a frontend to :class:`telegram.Bot` to the programmer, so they can focus on coding the bot. Its purpose is to receive the updates from Telegram and to deliver them to said dispatcher. It also runs in a separate thread, so the user can interact with the bot, for example on the command line. The dispatcher supports handlers for different kinds of data: Updates from Telegram, basic text commands and even arbitrary types. The updater can be started as a polling service or, for production, use a webhook to receive updates. This is achieved using the WebhookServer and WebhookHandler classes. Attributes: bot (:class:`telegram.Bot`): The bot used with this Updater. user_sig_handler (:obj:`signal`): signals the updater will respond to. update_queue (:obj:`Queue`): Queue for the updates. job_queue (:class:`telegram.ext.JobQueue`): Jobqueue for the updater. dispatcher (:class:`telegram.ext.Dispatcher`): Dispatcher that handles the updates and dispatches them to the handlers. running (:obj:`bool`): Indicates if the updater is running. Args: token (:obj:`str`, optional): The bot's token given by the @BotFather. base_url (:obj:`str`, optional): Base_url for the bot. workers (:obj:`int`, optional): Amount of threads in the thread pool for functions decorated with ``@run_async``. bot (:class:`telegram.Bot`, optional): A pre-initialized bot instance. If a pre-initialized bot is used, it is the user's responsibility to create it using a `Request` instance with a large enough connection pool. private_key (:obj:`bytes`, optional): Private key for decryption of telegram passport data. private_key_password (:obj:`bytes`, optional): Password for above private key. user_sig_handler (:obj:`function`, optional): Takes ``signum, frame`` as positional arguments. This will be called when a signal is received, defaults are (SIGINT, SIGTERM, SIGABRT) setable with :attr:`idle`. request_kwargs (:obj:`dict`, optional): Keyword args to control the creation of a `telegram.utils.request.Request` object (ignored if `bot` argument is used). The request_kwargs are very useful for the advanced users who would like to control the default timeouts and/or control the proxy used for http communication. Note: You must supply either a :attr:`bot` or a :attr:`token` argument. Raises: ValueError: If both :attr:`token` and :attr:`bot` are passed or none of them. """ _request = None def __init__(self, token=None, base_url=None, workers=4, bot=None, private_key=None, private_key_password=None, user_sig_handler=None, request_kwargs=None): if (token is None) and (bot is None): raise ValueError('`token` or `bot` must be passed') if (token is not None) and (bot is not None): raise ValueError('`token` and `bot` are mutually exclusive') if (private_key is not None) and (bot is not None): raise ValueError('`bot` and `private_key` are mutually exclusive') self.logger = logging.getLogger(__name__) con_pool_size = workers + 4 if bot is not None: self.bot = bot if bot.request.con_pool_size < con_pool_size: self.logger.warning( 'Connection pool of Request object is smaller than optimal value (%s)', con_pool_size) else: # we need a connection pool the size of: # * for each of the workers # * 1 for Dispatcher # * 1 for polling Updater (even if webhook is used, we can spare a connection) # * 1 for JobQueue # * 1 for main thread if request_kwargs is None: request_kwargs = {} if 'con_pool_size' not in request_kwargs: request_kwargs['con_pool_size'] = con_pool_size self._request = Request(**request_kwargs) self.bot = Bot(token, base_url, request=self._request, private_key=private_key, private_key_password=private_key_password) self.user_sig_handler = user_sig_handler self.update_queue = Queue() self.job_queue = JobQueue(self.bot) self.__exception_event = Event() self.dispatcher = Dispatcher( self.bot, self.update_queue, job_queue=self.job_queue, workers=workers, exception_event=self.__exception_event) self.last_update_id = 0 self.running = False self.is_idle = False self.httpd = None self.__lock = Lock() self.__threads = [] def _init_thread(self, target, name, *args, **kwargs): thr = Thread(target=self._thread_wrapper, name=name, args=(target,) + args, kwargs=kwargs) thr.start() self.__threads.append(thr) def _thread_wrapper(self, target, *args, **kwargs): thr_name = current_thread().name self.logger.debug('{0} - started'.format(thr_name)) try: target(*args, **kwargs) except Exception: self.__exception_event.set() self.logger.exception('unhandled exception in %s', thr_name) raise self.logger.debug('{0} - ended'.format(thr_name)) def start_polling(self, poll_interval=0.0, timeout=10, clean=False, bootstrap_retries=-1, read_latency=2., allowed_updates=None): """Starts polling updates from Telegram. Args: poll_interval (:obj:`float`, optional): Time to wait between polling updates from Telegram in seconds. Default is 0.0. timeout (:obj:`float`, optional): Passed to :attr:`telegram.Bot.get_updates`. clean (:obj:`bool`, optional): Whether to clean any pending updates on Telegram servers before actually starting to poll. Default is False. bootstrap_retries (:obj:`int`, optional): Whether the bootstrapping phase of the `Updater` will retry on failures on the Telegram server. * < 0 - retry indefinitely (default) * 0 - no retries * > 0 - retry up to X times allowed_updates (List[:obj:`str`], optional): Passed to :attr:`telegram.Bot.get_updates`. read_latency (:obj:`float` | :obj:`int`, optional): Grace time in seconds for receiving the reply from server. Will be added to the `timeout` value and used as the read timeout from server (Default: 2). Returns: :obj:`Queue`: The update queue that can be filled from the main thread. """ with self.__lock: if not self.running: self.running = True # Create & start threads self.job_queue.start() dispatcher_ready = Event() self._init_thread(self.dispatcher.start, "dispatcher", ready=dispatcher_ready) self._init_thread(self._start_polling, "updater", poll_interval, timeout, read_latency, bootstrap_retries, clean, allowed_updates) dispatcher_ready.wait() # Return the update queue so the main thread can insert updates return self.update_queue def start_webhook(self, listen='127.0.0.1', port=80, url_path='', cert=None, key=None, clean=False, bootstrap_retries=0, webhook_url=None, allowed_updates=None): """ Starts a small http server to listen for updates via webhook. If cert and key are not provided, the webhook will be started directly on http://listen:port/url_path, so SSL can be handled by another application. Else, the webhook will be started on https://listen:port/url_path Args: listen (:obj:`str`, optional): IP-Address to listen on. Default ``127.0.0.1``. port (:obj:`int`, optional): Port the bot should be listening on. Default ``80``. url_path (:obj:`str`, optional): Path inside url. cert (:obj:`str`, optional): Path to the SSL certificate file. key (:obj:`str`, optional): Path to the SSL key file. clean (:obj:`bool`, optional): Whether to clean any pending updates on Telegram servers before actually starting the webhook. Default is ``False``. bootstrap_retries (:obj:`int`, optional): Whether the bootstrapping phase of the `Updater` will retry on failures on the Telegram server. * < 0 - retry indefinitely (default) * 0 - no retries * > 0 - retry up to X times webhook_url (:obj:`str`, optional): Explicitly specify the webhook url. Useful behind NAT, reverse proxy, etc. Default is derived from `listen`, `port` & `url_path`. allowed_updates (List[:obj:`str`], optional): Passed to :attr:`telegram.Bot.set_webhook`. Returns: :obj:`Queue`: The update queue that can be filled from the main thread. """ with self.__lock: if not self.running: self.running = True # Create & start threads self.job_queue.start() self._init_thread(self.dispatcher.start, "dispatcher"), self._init_thread(self._start_webhook, "updater", listen, port, url_path, cert, key, bootstrap_retries, clean, webhook_url, allowed_updates) # Return the update queue so the main thread can insert updates return self.update_queue def _start_polling(self, poll_interval, timeout, read_latency, bootstrap_retries, clean, allowed_updates): # pragma: no cover # Thread target of thread 'updater'. Runs in background, pulls # updates from Telegram and inserts them in the update queue of the # Dispatcher. self.logger.debug('Updater thread started (polling)') self._bootstrap(bootstrap_retries, clean=clean, webhook_url='', allowed_updates=None) self.logger.debug('Bootstrap done') def polling_action_cb(): updates = self.bot.get_updates( self.last_update_id, timeout=timeout, read_latency=read_latency, allowed_updates=allowed_updates) if updates: if not self.running: self.logger.debug('Updates ignored and will be pulled again on restart') else: for update in updates: self.update_queue.put(update) self.last_update_id = updates[-1].update_id + 1 return True def polling_onerr_cb(exc): # Put the error into the update queue and let the Dispatcher # broadcast it self.update_queue.put(exc) self._network_loop_retry(polling_action_cb, polling_onerr_cb, 'getting Updates', poll_interval) def _network_loop_retry(self, action_cb, onerr_cb, description, interval): """Perform a loop calling `action_cb`, retrying after network errors. Stop condition for loop: `self.running` evaluates False or return value of `action_cb` evaluates False. Args: action_cb (:obj:`callable`): Network oriented callback function to call. onerr_cb (:obj:`callable`): Callback to call when TelegramError is caught. Receives the exception object as a parameter. description (:obj:`str`): Description text to use for logs and exception raised. interval (:obj:`float` | :obj:`int`): Interval to sleep between each call to `action_cb`. """ self.logger.debug('Start network loop retry %s', description) cur_interval = interval while self.running: try: if not action_cb(): break except RetryAfter as e: self.logger.info('%s', e) cur_interval = 0.5 + e.retry_after except TimedOut as toe: self.logger.debug('Timed out %s: %s', description, toe) # If failure is due to timeout, we should retry asap. cur_interval = 0 except InvalidToken as pex: self.logger.error('Invalid token; aborting') raise pex except TelegramError as te: self.logger.error('Error while %s: %s', description, te) onerr_cb(te) cur_interval = self._increase_poll_interval(cur_interval) else: cur_interval = interval if cur_interval: sleep(cur_interval) @staticmethod def _increase_poll_interval(current_interval): # increase waiting times on subsequent errors up to 30secs if current_interval == 0: current_interval = 1 elif current_interval < 30: current_interval += current_interval / 2 elif current_interval > 30: current_interval = 30 return current_interval def _start_webhook(self, listen, port, url_path, cert, key, bootstrap_retries, clean, webhook_url, allowed_updates): self.logger.debug('Updater thread started (webhook)') use_ssl = cert is not None and key is not None if not url_path.startswith('/'): url_path = '/{0}'.format(url_path) # Create Tornado app instance app = WebhookAppClass(url_path, self.bot, self.update_queue) # Form SSL Context # An SSLError is raised if the private key does not match with the certificate if use_ssl: try: ssl_ctx = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH) ssl_ctx.load_cert_chain(cert, key) except ssl.SSLError: raise TelegramError('Invalid SSL Certificate') else: ssl_ctx = None # Create and start server self.httpd = WebhookServer(port, app, ssl_ctx) if use_ssl: # DO NOT CHANGE: Only set webhook if SSL is handled by library if not webhook_url: webhook_url = self._gen_webhook_url(listen, port, url_path) self._bootstrap( max_retries=bootstrap_retries, clean=clean, webhook_url=webhook_url, cert=open(cert, 'rb'), allowed_updates=allowed_updates) elif clean: self.logger.warning("cleaning updates is not supported if " "SSL-termination happens elsewhere; skipping") self.httpd.serve_forever() @staticmethod def _gen_webhook_url(listen, port, url_path): return 'https://{listen}:{port}{path}'.format(listen=listen, port=port, path=url_path) def _bootstrap(self, max_retries, clean, webhook_url, allowed_updates, cert=None, bootstrap_interval=5): retries = [0] def bootstrap_del_webhook(): self.bot.delete_webhook() return False def bootstrap_clean_updates(): self.logger.debug('Cleaning updates from Telegram server') updates = self.bot.get_updates() while updates: updates = self.bot.get_updates(updates[-1].update_id + 1) return False def bootstrap_set_webhook(): self.bot.set_webhook( url=webhook_url, certificate=cert, allowed_updates=allowed_updates) return False def bootstrap_onerr_cb(exc): if not isinstance(exc, Unauthorized) and (max_retries < 0 or retries[0] < max_retries): retries[0] += 1 self.logger.warning('Failed bootstrap phase; try=%s max_retries=%s', retries[0], max_retries) else: self.logger.error('Failed bootstrap phase after %s retries (%s)', retries[0], exc) raise exc # Cleaning pending messages is done by polling for them - so we need to delete webhook if # one is configured. # We also take this chance to delete pre-configured webhook if this is a polling Updater. # NOTE: We don't know ahead if a webhook is configured, so we just delete. if clean or not webhook_url: self._network_loop_retry(bootstrap_del_webhook, bootstrap_onerr_cb, 'bootstrap del webhook', bootstrap_interval) retries[0] = 0 # Clean pending messages, if requested. if clean: self._network_loop_retry(bootstrap_clean_updates, bootstrap_onerr_cb, 'bootstrap clean updates', bootstrap_interval) retries[0] = 0 sleep(1) # Restore/set webhook settings, if needed. Again, we don't know ahead if a webhook is set, # so we set it anyhow. if webhook_url: self._network_loop_retry(bootstrap_set_webhook, bootstrap_onerr_cb, 'bootstrap set webhook', bootstrap_interval) def stop(self): """Stops the polling/webhook thread, the dispatcher and the job queue.""" self.job_queue.stop() with self.__lock: if self.running or self.dispatcher.has_running_threads: self.logger.debug('Stopping Updater and Dispatcher...') self.running = False self._stop_httpd() self._stop_dispatcher() self._join_threads() # Stop the Request instance only if it was created by the Updater if self._request: self._request.stop() def _stop_httpd(self): if self.httpd: self.logger.debug('Waiting for current webhook connection to be ' 'closed... Send a Telegram message to the bot to exit ' 'immediately.') self.httpd.shutdown() self.httpd = None def _stop_dispatcher(self): self.logger.debug('Requesting Dispatcher to stop...') self.dispatcher.stop() def _join_threads(self): for thr in self.__threads: self.logger.debug('Waiting for {0} thread to end'.format(thr.name)) thr.join() self.logger.debug('{0} thread has ended'.format(thr.name)) self.__threads = [] def signal_handler(self, signum, frame): self.is_idle = False if self.running: self.logger.info('Received signal {} ({}), stopping...'.format( signum, get_signal_name(signum))) self.stop() if self.user_sig_handler: self.user_sig_handler(signum, frame) else: self.logger.warning('Exiting immediately!') import os os._exit(1) def idle(self, stop_signals=(SIGINT, SIGTERM, SIGABRT)): """Blocks until one of the signals are received and stops the updater. Args: stop_signals (:obj:`iterable`): Iterable containing signals from the signal module that should be subscribed to. Updater.stop() will be called on receiving one of those signals. Defaults to (``SIGINT``, ``SIGTERM``, ``SIGABRT``). """ for sig in stop_signals: signal(sig, self.signal_handler) self.is_idle = True while self.is_idle: sleep(1)