rclcpp_action std::runtime_error when killing action server

[fafux]

Hi, I am working on Ubuntu 24.04 with ROS2 jazzy.
I followed the tutorials on how to "Writing an action server and client (C++)". I launched the server and then the client as written in the tutorial. If I send a SIGINT to the server while the action is executing (^C) I get an std::runtime_error specifically:

[INFO] [1740584812.433644455] [rclcpp]: signal_handler(signum=2)
terminate called after throwing an instance of 'std::runtime_error'
  what():  Asked to publish result for goal that does not exist

I think this is a bug. The runtime error is thrown before rclcpp::shutdown() is called. As far as I know the server should send a notification to the client that the goal was canceled or aborted, call rclcpp::shutdown(), and finish cleanly. The problem is that, with this bug, the resources are not released.

[sloretz]

Just adding the location of the exception:

rclcpp/rclcpp_action/src/server.cpp

Line 733 in 48a4761

throw std::runtime_error("Asked to publish result for goal that does not exist");

[fujitatomoya]

about the exception on action server, i think you met the racy condition. I cannot reproduce this issue though.

root@tomoyafujita:~/ros2_ws/colcon_ws# ros2 run action_tutorials_cpp fibonacci_action_server
[INFO] [1741309035.485585161] [fibonacci_action_server]: Received goal request with order 10
[INFO] [1741309035.486094219] [fibonacci_action_server]: Executing goal
[INFO] [1741309035.486319267] [fibonacci_action_server]: Publish feedback
[INFO] [1741309036.486456961] [fibonacci_action_server]: Publish feedback
^C[INFO] [1741309037.169525708] [rclcpp]: signal_handler(signum=2)
root@tomoyafujita:~/ros2_ws/colcon_ws# ros2 run action_tutorials_cpp fibonacci_action_server
[INFO] [1741309042.508744397] [fibonacci_action_server]: Received goal request with order 10
[INFO] [1741309042.509333889] [fibonacci_action_server]: Executing goal
[INFO] [1741309042.509530099] [fibonacci_action_server]: Publish feedback
[INFO] [1741309043.509735177] [fibonacci_action_server]: Publish feedback
^C[INFO] [1741309044.408719362] [rclcpp]: signal_handler(signum=2)
root@tomoyafujita:~/ros2_ws/colcon_ws# ros2 run action_tutorials_cpp fibonacci_action_server
[INFO] [1741309049.774068952] [fibonacci_action_server]: Received goal request with order 10
[INFO] [1741309049.776226357] [fibonacci_action_server]: Executing goal
[INFO] [1741309049.777100021] [fibonacci_action_server]: Publish feedback
[INFO] [1741309050.776877790] [fibonacci_action_server]: Publish feedback
^C[INFO] [1741309051.480142554] [rclcpp]: signal_handler(signum=2)

The runtime error is thrown before rclcpp::shutdown() is called.

i think Context::shutdown() is called by deferred signal handler when the SIGINT comes in, it shuts down all the context gracefully.

As far as I know the server should send a notification to the client that the goal was canceled or aborted

this seems like a bug, unexpected behavior.
action client is waiting for the result, and action server actually tries to publish action_msgs::msg::GoalStatus::STATUS_CANCELED during destruction.

rclcpp/rclcpp_action/include/rclcpp_action/server_goal_handle.hpp

Lines 246 to 251 in 48a4761

	// Cancel goal if handle was allowed to destruct without reaching a terminal state
	if (try_canceling()) {
	auto null_result = std::make_shared<typename ActionT::Impl::GetResultService::Response>();
	null_result->status = action_msgs::msg::GoalStatus::STATUS_CANCELED;
	on_terminal_state_(uuid_, null_result);
	}