debian-python-amqp/demo/amqp_clock.py

79 lines
2.1 KiB
Python
Executable File

#!/usr/bin/env python
"""
AMQP Clock
Fires off simple messages at one-minute intervals to a topic
exchange named 'clock', with the topic of the message being
the local time as 'year.month.date.dow.hour.minute',
for example: '2007.11.26.1.12.33', where the dow (day of week)
is 0 for Sunday, 1 for Monday, and so on (similar to Unix crontab).
A consumer could then bind a queue to the routing key '#.0'
for example to get a message at the beginning of each hour.
2007-11-26 Barry Pederson <bp@barryp.org>
"""
from datetime import datetime
from optparse import OptionParser
from time import sleep
import amqp
Message = amqp.Message
EXCHANGE_NAME = 'clock'
TOPIC_PATTERN = '%Y.%m.%d.%w.%H.%M' # Python datetime.strftime() pattern
def main():
parser = OptionParser()
parser.add_option(
'--host', dest='host',
help='AMQP server to connect to (default: %default)',
default='localhost',
)
parser.add_option(
'-u', '--userid', dest='userid',
help='AMQP userid to authenticate as (default: %default)',
default='guest',
)
parser.add_option(
'-p', '--password', dest='password',
help='AMQP password to authenticate with (default: %default)',
default='guest',
)
parser.add_option(
'--ssl', dest='ssl', action='store_true',
help='Enable SSL with AMQP server (default: not enabled)',
default=False,
)
options, args = parser.parse_args()
conn = amqp.Connection(options.host, options.userid, options.password)
ch = conn.channel()
ch.exchange_declare(EXCHANGE_NAME, type='topic')
# Make sure our first message is close to the beginning
# of a minute
now = datetime.now()
if now.second > 0:
sleep(60 - now.second)
while True:
now = datetime.now()
msg = Message(timestamp=now)
msg_topic = now.strftime(TOPIC_PATTERN)
ch.basic_publish(msg, EXCHANGE_NAME, routing_key=msg_topic)
# Don't know how long the basic_publish took, so
# grab the time again.
now = datetime.now()
sleep(60 - now.second)
ch.close()
conn.close()
if __name__ == '__main__':
main()