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# Copyright 2012 GRNET S.A. All rights reserved.
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#
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# Redistribution and use in source and binary forms, with or
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# without modification, are permitted provided that the following
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# conditions are met:
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#
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#   1. Redistributions of source code must retain the above
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#      copyright notice, this list of conditions and the following
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#      disclaimer.
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#
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#   2. Redistributions in binary form must reproduce the above
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#      copyright notice, this list of conditions and the following
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#      disclaimer in the documentation and/or other materials
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#      provided with the distribution.
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#
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# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
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# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
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# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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# POSSIBILITY OF SUCH DAMAGE.
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#
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# The views and conclusions contained in the software and
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# documentation are those of the authors and should not be
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# interpreted as representing official policies, either expressed
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# or implied, of GRNET S.A.
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import pika
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import json
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import uuid
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from urlparse import urlparse
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from hashlib import sha1
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from random import random
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from time import time
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def exchange_connect(exchange, vhost='/'):
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    """Format exchange as a URI: rabbitmq://user:pass@host:port/exchange"""
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    parts = urlparse(exchange)
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    if parts.scheme != 'rabbitmq':
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        return None
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    if len(parts.path) < 2 or not parts.path.startswith('/'):
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        return None
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    exchange = parts.path[1:]
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    connection = pika.BlockingConnection(pika.ConnectionParameters(
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                    host=parts.hostname, port=parts.port, virtual_host=vhost,
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                    credentials=pika.PlainCredentials(parts.username, parts.password)))
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    channel = connection.channel()
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    channel.exchange_declare(exchange=exchange, type='topic', durable=True)
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    return (connection, channel, exchange)
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def exchange_close(conn):
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    connection, channel, exchange = conn
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    connection.close()
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def exchange_send(conn, key, value):
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    """Messages are sent to exchanges at a key."""
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    connection, channel, exchange = conn
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    channel.basic_publish(exchange=exchange,
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                          routing_key=key,
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                          body=json.dumps(value))
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def exchange_route(conn, key, queue):
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    """Set up routing of keys to queue."""
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    connection, channel, exchange = conn
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    channel.queue_declare(queue=queue, durable=True,
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                          exclusive=False, auto_delete=False)
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    channel.queue_bind(exchange=exchange,
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                       queue=queue,
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                       routing_key=key)
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def queue_callback(conn, queue, cb):
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    def handle_delivery(channel, method_frame, header_frame, body):
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        #print 'Basic.Deliver %s delivery-tag %i: %s' % (header_frame.content_type,
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        #                                                method_frame.delivery_tag,
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        #                                                body)
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        if cb:
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            cb(json.loads(body))
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        channel.basic_ack(delivery_tag=method_frame.delivery_tag)
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    connection, channel, exchange = conn
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    channel.basic_consume(handle_delivery, queue=queue)
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def queue_start(conn):
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    connection, channel, exchange = conn
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    channel.start_consuming()
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class Receipt(object):
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    def __init__(self, client, user, instance, resource, value, details={}):
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        self.eventVersion = '1.0'
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        self.occurredMillis = int(time() * 1000)
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        self.receivedMillis = self.occurredMillis
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        self.clientID = client
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        self.userID = user
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        self.instanceID = instance
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        self.resource = resource
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        self.value = value
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        self.details = details
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        hash = sha1()
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        hash.update(json.dumps([client, user, resource, value, details, random()]))
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        self.id = hash.hexdigest()
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    def format(self):
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        return self.__dict__