ROS2_Action simple example code

 

https://docs.ros.org/en/eloquent/Tutorials/Actions/Writing-a-Py-Action-Server-Client.html

Writing an action server and client (Python) — ROS 2 Documentation: Eloquent documentation

 

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기본구

 

 

# SERVER

import time

import rclpy
from rclpy.action import ActionServer
from rclpy.node import Node

from action_tutorials_interfaces.action import Fibonacci


class FibonacciActionServer(Node):

    def __init__(self):
        super().__init__('fibonacci_action_server')
        self._action_server = ActionServer(
            self,
            Fibonacci,
            'fibonacci',
            self.execute_callback)

    def execute_callback(self, goal_handle):
        self.get_logger().info('Executing goal...')

        feedback_msg = Fibonacci.Feedback()
        feedback_msg.partial_sequence = [0, 1]

        for i in range(1, goal_handle.request.order):
            feedback_msg.partial_sequence.append(
                feedback_msg.partial_sequence[i] + feedback_msg.partial_sequence[i-1])
            self.get_logger().info('Feedback: {0}'.format(feedback_msg.partial_sequence))
            goal_handle.publish_feedback(feedback_msg)
            time.sleep(1)

        goal_handle.succeed()

        result = Fibonacci.Result()
        result.sequence = feedback_msg.partial_sequence
        return result

def main(args=None):
    rclpy.init(args=args)

    action_client = FibonacciActionServer()

    rclpy.spin(action_client)


if __name__ == '__main__':
    main()

 

# CLIENT

import rclpy
from rclpy.action import ActionClient
from rclpy.node import Node

from action_tutorials_interfaces.action import Fibonacci


class FibonacciActionClient(Node):

    def __init__(self):
        super().__init__('fibonacci_action_client')
        self._action_client = ActionClient(self, Fibonacci, 'fibonacci')
        self.tmp=True

    def send_goal(self, order):
        goal_msg = Fibonacci.Goal()
        goal_msg.order = order

        self._action_client.wait_for_server()

        self.get_logger().warning(f"{1} << Goal Service : {'Request'}")

        self._send_goal_future = self._action_client.send_goal_async(goal_msg, feedback_callback=self.feedback_callback)

        self._send_goal_future.add_done_callback(self.goal_response_callback)

    def goal_response_callback(self, future):
        self.get_logger().warning(f"{2} << Goal Service : {'Response'} < response : {future.result()}")
        goal_handle = future.result()
        if not goal_handle.accepted:
            self.get_logger().info('Goal rejected :(')
            return

        self._get_result_future = goal_handle.get_result_async()
        self.get_logger().warning(f"{3} << Result Service : {'Request'} < {self._get_result_future}")
        self._get_result_future.add_done_callback(self.get_result_callback)

    def get_result_callback(self, future):
        result = future.result().result
        self.get_logger().warning(f"{5} << Result Service : {'Response'} < Result : {result.sequence}")
        rclpy.shutdown()

    def feedback_callback(self, feedback_msg):
        if self.tmp is True:
            self.get_logger().warning(f"{4} << Feedback Topic : {'TOPIC'}")
            self.tmp = False
        feedback = feedback_msg.feedback
        self.get_logger().info('Received feedback: {0}'.format(feedback.partial_sequence))


def main(args=None):
    rclpy.init(args=args)

    action_client = FibonacciActionClient()

    action_client.send_goal(10)

    rclpy.spin(action_client)


if __name__ == '__main__':
    main()

 

print out