# Copyright (c) 2017  Janus Development Team
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

import json
from telegram.ext import Updater, MessageHandler, Filters

with open('config.json') as fp:
  config = json.load(fp)


def reply(bot, update):
  update.message.reply_text(update.message.text)


def main():
  updater = Updater(config['token'])
  updater.dispatcher.add_handler(MessageHandler(Filters.text, reply))
  updater.start_polling()
  updater.idle()


if __name__ == '__main__':
  main()

# Copyright (c) 2017  Janus Development Team
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

import json
import functools
import traceback
import sys
from telegram.ext import Updater, MessageHandler, Filters

with open('config.json') as fp:
  config = json.load(fp)


def handler(func):
  """
  Decorator for handlers that catches errors.
  """

  def wrapper(bot, update):
    try:
      return func(bot, update)
    except:
      exc_string = traceback.format_exc()
      print(exc_string, file=sys.stderr)
      if config.get('debug'):
        update.message.reply_text(exc_string)
      else:
        update.message.reply_text('Internal Error')

  return wrapper


@handler
def reply(bot, update):
  foo
  update.message.reply_text(update.message.text)


def main():
  updater = Updater(config['token'])
  updater.dispatcher.add_handler(MessageHandler(Filters.text, reply))
  updater.start_polling()
  updater.idle()


if __name__ == '__main__':
  main()

add exception handling to telegram bot