#!/usr/bin/env python # # A library that provides a Python interface to the Telegram Bot API # Copyright (C) 2015-2016 # 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 os import ssl from threading import Thread, Lock, current_thread, Event from time import sleep import subprocess from signal import signal, SIGINT, SIGTERM, SIGABRT from queue import Queue from telegram import Bot, TelegramError, NullHandler from telegram.ext import dispatcher, Dispatcher, JobQueue from telegram.error import Unauthorized, InvalidToken from telegram.utils.webhookhandler import (WebhookServer, WebhookHandler) logging.getLogger(__name__).addHandler(NullHandler()) class Updater(object): """ This class, which employs the Dispatcher class, provides a frontend to 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: Args: token (Optional[str]): The bot's token given by the @BotFather base_url (Optional[str]): workers (Optional[int]): Amount of threads in the thread pool for functions decorated with @run_async bot (Optional[Bot]): job_queue_tick_interval(Optional[float]): The interval the queue should be checked for new tasks. Defaults to 1.0 Raises: ValueError: If both `token` and `bot` are passed or none of them. """ def __init__(self, token=None, base_url=None, workers=4, bot=None, job_queue_tick_interval=1.0): 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 bot is not None: self.bot = bot else: self.bot = Bot(token, base_url) self.update_queue = Queue() self.job_queue = JobQueue(self.bot, job_queue_tick_interval) self.__exception_event = Event() self.dispatcher = Dispatcher(self.bot, self.update_queue, workers, self.__exception_event) self.last_update_id = 0 self.logger = logging.getLogger(__name__) self.running = False self.is_idle = False self.httpd = None self.__lock = Lock() self.__threads = [] """:type: list[Thread]""" 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') raise self.logger.debug('{0} - ended'.format(thr_name)) def start_polling(self, poll_interval=0.0, timeout=10, network_delay=2, clean=False, bootstrap_retries=0): """ Starts polling updates from Telegram. Args: poll_interval (Optional[float]): Time to wait between polling updates from Telegram in seconds. Default is 0.0 timeout (Optional[float]): Passed to Bot.getUpdates network_delay (Optional[float]): Passed to Bot.getUpdates clean (Optional[bool]): Whether to clean any pending updates on Telegram servers before actually starting to poll. Default is False. bootstrap_retries (Optional[int[): Whether the bootstrapping phase of the `Updater` will retry on failures on the Telegram server. | < 0 - retry indefinitely | 0 - no retries (default) | > 0 - retry up to X times Returns: 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._init_thread(self.dispatcher.start, "dispatcher") self._init_thread(self._start_polling, "updater", poll_interval, timeout, network_delay, bootstrap_retries, clean) # 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): """ 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 (Optional[str]): IP-Address to listen on port (Optional[int]): Port the bot should be listening on url_path (Optional[str]): Path inside url cert (Optional[str]): Path to the SSL certificate file key (Optional[str]): Path to the SSL key file clean (Optional[bool]): Whether to clean any pending updates on Telegram servers before actually starting the webhook. Default is False. bootstrap_retries (Optional[int[): Whether the bootstrapping phase of the `Updater` will retry on failures on the Telegram server. | < 0 - retry indefinitely | 0 - no retries (default) | > 0 - retry up to X times webhook_url (Optional[str]): Explicitly specifiy the webhook url. Useful behind NAT, reverse proxy, etc. Default is derived from `listen`, `port` & `url_path`. Returns: 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._init_thread(self.dispatcher.start, "dispatcher"), self._init_thread(self._start_webhook, "updater", listen, port, url_path, cert, key, bootstrap_retries, clean, webhook_url) # Return the update queue so the main thread can insert updates return self.update_queue def _start_polling(self, poll_interval, timeout, network_delay, bootstrap_retries, clean): """ Thread target of thread 'updater'. Runs in background, pulls updates from Telegram and inserts them in the update queue of the Dispatcher. """ cur_interval = poll_interval self.logger.debug('Updater thread started') self._bootstrap(bootstrap_retries, clean=clean, webhook_url='') while self.running: try: updates = self.bot.getUpdates(self.last_update_id, timeout=timeout, network_delay=network_delay) except TelegramError as te: self.logger.error("Error while getting Updates: {0}".format(te)) # Put the error into the update queue and let the Dispatcher # broadcast it self.update_queue.put(te) cur_interval = self._increase_poll_interval(cur_interval) else: if not self.running: if len(updates) > 0: self.logger.debug('Updates ignored and will be pulled ' 'again on restart.') break if updates: for update in updates: self.update_queue.put(update) self.last_update_id = updates[-1].update_id + 1 cur_interval = poll_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): self.logger.debug('Updater thread started') use_ssl = cert is not None and key is not None if not url_path.startswith('/'): url_path = '/{0}'.format(url_path) # Create and start server self.httpd = WebhookServer((listen, port), WebhookHandler, self.update_queue, url_path) if use_ssl: self._check_ssl_cert(cert, key) # 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')) elif clean: self.logger.warning("cleaning updates is not supported if " "SSL-termination happens elsewhere; skipping") self.httpd.serve_forever(poll_interval=1) def _check_ssl_cert(self, cert, key): # Check SSL-Certificate with openssl, if possible try: exit_code = subprocess.call( ["openssl", "x509", "-text", "-noout", "-in", cert], stdout=open(os.devnull, 'wb'), stderr=subprocess.STDOUT) except OSError: exit_code = 0 if exit_code is 0: try: self.httpd.socket = ssl.wrap_socket(self.httpd.socket, certfile=cert, keyfile=key, server_side=True) except ssl.SSLError as error: self.logger.exception('Failed to init SSL socket') raise TelegramError(str(error)) else: raise TelegramError('SSL Certificate invalid') @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, cert=None): retries = 0 while True: try: if clean: # Disable webhook for cleaning self.bot.setWebhook(webhook_url='') self._clean_updates() self.bot.setWebhook(webhook_url=webhook_url, certificate=cert) except (Unauthorized, InvalidToken): raise except TelegramError: msg = 'error in bootstrap phase; try={0} max_retries={1}'.format(retries, max_retries) if max_retries < 0 or retries < max_retries: self.logger.warning(msg) retries += 1 else: self.logger.exception(msg) raise else: break sleep(1) def _clean_updates(self): self.logger.debug('Cleaning updates from Telegram server') updates = self.bot.getUpdates() while updates: updates = self.bot.getUpdates(updates[-1].update_id + 1) def stop(self): """ Stops the polling/webhook thread, the dispatcher and the job queue """ self.job_queue.stop() with self.__lock: if self.running: self.logger.debug('Stopping Updater and Dispatcher...') self.running = False self._stop_httpd() self._stop_dispatcher() self._join_threads() # async threads must be join()ed only after the dispatcher # thread was joined, otherwise we can still have new async # threads dispatched self._join_async_threads() 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_async_threads(self): with dispatcher.async_lock: threads = list(dispatcher.async_threads) total = len(threads) for i, thr in enumerate(threads): self.logger.debug('Waiting for async thread {0}/{1} to end'.format(i, total)) thr.join() self.logger.debug('async thread {0}/{1} has ended'.format(i, total)) 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.stop() 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: 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)