new_contents: #!/usr/bin/python3
  #
  #  This file is part of the KNOT Project
  #
  #  Copyright (c) 2019, CESAR. All rights reserved.
  #
  #   This library is free software; you can redistribute it and/or
  #   modify it under the terms of the GNU Lesser General Public
  #   License as published by the Free Software Foundation; either
  #   version 2.1 of the License, or (at your option) any later version.
  #
  #   This library 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 General Public License for more details.
  #
  #   You should have received a copy of the GNU Lesser General Public
  #   License along with this library; if not, write to the Free Software
  #   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  
  import pika
  import logging
  
  logging.basicConfig(
      format='%(asctime)s %(message)s',
      level=logging.INFO,
      datefmt='%Y-%m-%d %H:%M:%S')
  
  connection = pika.BlockingConnection(
      pika.ConnectionParameters(host='localhost'))
  channel = connection.channel()
  
  cloud_exchange = 'cloud'
  fog_exchange = 'fog'
  
  EVENT_UNREGISTER = 'device.unregister'
  KEY_UNREGISTERED = 'device.unregistered'
  
  channel.exchange_declare(exchange=fog_exchange, durable=True,
  exchange_type='topic')
  channel.exchange_declare(exchange=cloud_exchange, durable=True,
  exchange_type='topic')
  
  result = channel.queue_declare('', exclusive=True)
  queue_name = result.method.queue
  
  channel.queue_bind(
          exchange=cloud_exchange, queue=queue_name, routing_key='device.*')
  
  def callback(ch, method, properties, body):
      logging.info("%r:%r" % (method.routing_key, body))
  
      if method.routing_key == EVENT_UNREGISTER:
          message = body
          channel.basic_publish(exchange=fog_exchange,
                                routing_key=KEY_UNREGISTERED, body=message)
  
      logging.info(" [x] Sent %r" % (message))
  
  channel.basic_consume(
      queue=queue_name, on_message_callback=callback, auto_ack=True)
  
  logging.info('Listening to messages')
  channel.start_consuming()
  
subject: Add mock script to test messages in amqp