listener_connection_header.py

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#!/usr/bin/env python
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# Revision $Id: gossipbot 3529 2009-01-23 22:35:53Z sfkwc $

## listener_connection_header looks at the connection header
## from the received message to determine who it is talking to.

PKG = 'rospy_tutorials'
import roslib; roslib.load_manifest(PKG)

import sys 

import rospy
from std_msgs.msg import String

NAME = 'listener_connection_header'

def callback(data):
    chatter = data.data
    if 'callerid' in data._connection_header:
        who = data._connection_header['callerid']
    else:
        who = 'unknown'
    if 'cookies' in data._connection_header:
        print "%s just offered me %s cookies"%(who, data._connection_header['cookies'])
    else:
        print "I just heard %s from %s"%(chatter, who)
    
def listener_header():
    rospy.Subscriber("chatter", String, callback)
    rospy.init_node(NAME, anonymous=True)
    rospy.spin()
        
if __name__ == '__main__':
    try:
        listener_header()
    except KeyboardInterrupt, e:
        pass
    print "exiting"