#!/usr/bin/env python

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import sys
import logging

from pithos.lib.queue import (exchange_connect, exchange_close,
    exchange_send, exchange_route, queue_callback, queue_start)

from optparse import OptionParser


BROKER_HOST = 'localhost'
BROKER_PORT = 5672
BROKER_USER = 'guest'
BROKER_PASSWORD = 'guest'
BROKER_VHOST = '/'

CONSUMER_QUEUE = 'feed'
CONSUMER_EXCHANGE = 'sample'
CONSUMER_KEY = '#'

DEBUG = False


if __name__ == '__main__':
    parser = OptionParser()
    parser.add_option('-v', '--verbose', action='store_true', default=False,
                      dest='verbose', help='Enable verbose logging')
    parser.add_option('--host', default=BROKER_HOST, dest='host',
                      help='RabbitMQ host (default: %s)' % BROKER_HOST)
    parser.add_option('--port', default=BROKER_PORT, dest='port',
                      help='RabbitMQ port (default: %s)' % BROKER_PORT, type='int')
    parser.add_option('--user', default=BROKER_USER, dest='user',
                      help='RabbitMQ user (default: %s)' % BROKER_USER)
    parser.add_option('--password', default=BROKER_PASSWORD, dest='password',
                      help='RabbitMQ password (default: %s)' % BROKER_PASSWORD)
    parser.add_option('--vhost', default=BROKER_VHOST, dest='vhost',
                      help='RabbitMQ vhost (default: %s)' % BROKER_VHOST)
    parser.add_option('--queue', default=CONSUMER_QUEUE, dest='queue',
                      help='RabbitMQ queue (default: %s)' % CONSUMER_QUEUE)
    parser.add_option('--exchange', default=CONSUMER_EXCHANGE, dest='exchange',
                      help='RabbitMQ exchange (default: %s)' % CONSUMER_EXCHANGE)
    parser.add_option('--key', default=CONSUMER_KEY, dest='key',
                      help='RabbitMQ key (default: %s)' % CONSUMER_KEY)
    parser.add_option('--callback', default=None, dest='callback',
                      help='Callback function to consume messages')
    parser.add_option('--test', action='store_true', default=False,
                      dest='test', help='Produce a dummy message for testing')
    opts, args = parser.parse_args()
    
    if opts.verbose:
        DEBUG = True
    logging.basicConfig(format='%(asctime)s [%(levelname)s] %(name)s %(message)s',
                        datefmt='%Y-%m-%d %H:%M:%S',
                        level=logging.DEBUG if DEBUG else logging.INFO)
    logger = logging.getLogger('dispatcher')
    
    exchange = 'rabbitmq://%s:%s@%s:%s/%s' % (opts.user, opts.password, opts.host, opts.port, opts.exchange)
    connection = exchange_connect(exchange)
    if opts.test:
        exchange_send(connection, opts.key, {"test": "0123456789"})
        exchange_close(connection)
        sys.exit()
    
    callback = None
    if opts.callback:
        cb = opts.callback.rsplit('.', 1)
        if len(cb) == 2:
            __import__(cb[0])
            cb_module = sys.modules[cb[0]]
            callback = getattr(cb_module, cb[1])
    
    def handle_message(msg):
        logger.debug('%s', msg)
        if callback:
            callback(msg)
    
    exchange_route(connection, opts.key, opts.queue)
    queue_callback(connection, opts.queue, handle_message)
    try:
        queue_start(connection)
    except KeyboardInterrupt:
        pass