I'm using ROS 2 Foxy on Ubuntu 20.04.

Something wacky is going on with my Durations.

#!/usr/bin/env python3

from control_msgs.action import FollowJointTrajectory

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

from trajectory_msgs.msg import JointTrajectoryPoint


class TrajectoryActionClient(Node):
    def __init__(self):
        super().__init__('trajectory_action_client')
        self._action_client = ActionClient(self, FollowJointTrajectory,
                                           '/stretch_controller/follow_joint_trajectory')

        goal = FollowJointTrajectory.Goal()
        goal.trajectory.joint_names = ['wrist_extension']
        p0 = JointTrajectoryPoint()
        p0.positions = [0.1]
        p0.velocities = [0.0]
        p0.accelerations = [0.0]
        goal.trajectory.points.append(p0)

        p1 = JointTrajectoryPoint()
        p1.positions = [0.1]
        p1.velocities = [0.0]
        p1.accelerations = [0.0]
        p1.time_from_start = Duration(seconds=5).to_msg()
        goal.trajectory.points.append(p1)

        self._send_goal_future = self._action_client.send_goal_async(goal)
        self._send_goal_future.add_done_callback(self.goal_response_callback)

    def goal_response_callback(self, future):
        goal_handle = future.result()
        if not goal_handle.accepted:
            return

        self._get_result_future = goal_handle.get_result_async()
        self._get_result_future.add_done_callback(self.get_result_callback)

    def get_result_callback(self, future):
        rclpy.shutdown()


def main(args=None):
    rclpy.init(args=args)
    node = TrajectoryActionClient()
    rclpy.spin(node)


if __name__ == '__main__':
    main()

If I run this code as is, I get the following:

terminate called after throwing an instance of 'eprosima::fastcdr::exception::NotEnoughMemoryException'
  what():  Not enough memory in the buffer stream

But if I comment out the line

p1.time_from_start = Duration(seconds=5).to_msg()

It runs fine. Changing it to

p1.time_from_start.sec = 5

also doesn't work.