Is it possible to shut down a service from its client?

edit

Hi,

It's indeed possible, but I wouldn't recommend it to you, as other node can still be using this service, or the service can probably be restarted in other way (for example, wait a parameter to be on, or wait for an other service to be called).

To make the server kill himself : What you can do is to set a flag to shutdown the service : (Warning : not safe, the script can terminate before the response is sent, use at your own risk)

from beginner_tutorials.srv import *
import rospy

manual_shutdown = False

def handle_add_two_ints(req):
    global manual_shutdown
    print "Returning [%s + %s = %s]"%(req.a, req.b, (req.a + req.b))
    response = AddTwoIntsResponse(req.a + req.b)
    manual_shutdown = True
    return response 

def add_two_ints_server():
    rospy.init_node('add_two_ints_server')
    s = rospy.Service('add_two_ints', AddTwoInts, handle_add_two_ints)
    print "Ready to add two ints."
    r = rospy.Rate(10)
    while not rospy.is_shutdown() and not manual_shutdown:
        r.sleep()
    rospy.sleep(1)
    s.shutdown()

if __name__ == "__main__":
    add_two_ints_server()

Also, you can replace the signal_shutdown by what you want or even put the "manual_shutdown" in the while-loop and do thing after the loop.

I used a while loop instead of rospy.spin() , you can check why here : https://answers.ros.org/question/1103...

For completion, you can check these questions : https://answers.ros.org/question/1981... or https://answers.ros.org/question/1099...

Edit 2 : To make the client kill the server (make a node kill another node):

You can apply the method 1 above to create a "kill me" service and call it from the client.

Or even simpler, you just have to use the rosnode command :

node1:

import rospy
def node1():
    rospy.init_node('node1')
    r = rospy.Rate(10)
    while not rospy.is_shutdown():
        r.sleep()

if __name__ == "__main__":
    node1()

node 2:

import rospy
from subprocess import call
def node2():
    rospy.init_node('node2')
    rospy.sleep(10) # Wait 10 second to kill node1
    call(["rosnode", "kill", "node1"], shell=True) # be careful here https://stackoverflow.com/questions/3172470/actual-meaning-of-shell-true-in-subprocess

if __name__ == "__main__":
    node2()

Edit 1 : Some more answers :

(1) My code is not good at all so I edited it, if you don't return immediately after setting manual_shutdown = True, the client will have an error since the connection is broken (in rospy, all callback are in a thread). The error :

ERROR: transport error completing service call: unable to receive data from sender, check sender's logs for details

You can try it by adding a rospy.sleep(1) after the manual_shutdown=True to see the error

You can try to minimize the effect by putting the flag to True just before the return and putting a rospy.sleep() after the loop, but it's quite a ugly method. I'm still searching a correct way to do this

(2) you can add and you SHOULD add a rospy.sleep() or a rospy.rate() in the loop in Python, otherwise you CPU will work for nothing. You can check with the command top the CPU usage :

top without rospy.rate(10 ... (more)