ROS Service Client

The Follow Along Examples:

Follow along: ROS Topic Subscriber Example

The program launching process along with parameter settings are all simplified and set up on the Jupyter Notebook Environment.

Open the 02_01_ros_service_server.ipynb Jupyter Notebook
Import the necessary python libraries and modules
Follow and Execute the example codes

(The Jetson Board used for these examples are => Jetson Nano)

Open the following jupyter notebook:

02_01_ros_service_server.ipynb
To run the cells within the notebook use Ctrl + Enter

Import print_function from __future__ module for Python3 compatibility
Import AddTwoInts, AddTwoIntsResponse from rospy_tutorials.srv module
Import rospy modules

from __future__ import print_function
from rospy_tutorials.srv import AddTwoInts,AddTwoIntsResponse
import rospy

Create handle_add_two_ints() function
Output req.a, req.b, req.a + req.b
Return instances of req.a + req.b in AddTwoIntsResponse

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

Create add_two_ints_server() function
Create add_two_ints_server Node
Create add_two_ints Service

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.")
    rospy.spin()

Execute the add_two_ints_server() function

add_two_ints_server()