Error happens when mock_node is restarted

[jeroenzwan]

This is the error received when shutting down the mock node and restarting it

[mros2_reasoner_node-1]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/action/server.py", line 324, in _execute_goal
[mros2_reasoner_node-1]     execute_result = await await_or_execute(execute_callback, goal_handle)
[mros2_reasoner_node-1]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 107, in await_or_execute
[mros2_reasoner_node-1]     return callback(*args)
[mros2_reasoner_node-1]   File "/home/jeroen/Thesis/pipeline_exemplar/build/mros2_reasoner/mros2_reasoner/ros_reasoner.py", line 130, in objective_action_callback
[mros2_reasoner_node-1]     self.remove_objective(old_objective.name)
[mros2_reasoner_node-1]   File "/home/jeroen/Thesis/pipeline_exemplar/build/mros2_reasoner/mros2_reasoner/reasoner.py", line 58, in remove_objective
[mros2_reasoner_node-1]     destroy_entity(old_fg_instance)
[mros2_reasoner_node-1]   File "/usr/local/lib/python3.10/dist-packages/owlready2/prop.py", line 986, in destroy_entity
[mros2_reasoner_node-1]     e.namespace.world.graph.destroy_entity(e.storid, destroyer, relation_updater, undoer_objs, undoer_datas)
[mros2_reasoner_node-1] AttributeError: 'NoneType' object has no attribute 'namespace'
[mros2_reasoner_node-1] Traceback (most recent call last):
[mros2_reasoner_node-1]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/action/server.py", line 324, in _execute_goal
[mros2_reasoner_node-1]     execute_result = await await_or_execute(execute_callback, goal_handle)
[mros2_reasoner_node-1]   File "/opt/ros/humble/local/lib/python3.10/dist-packages/rclpy/executors.py", line 107, in await_or_execute
[mros2_reasoner_node-1]     return callback(*args)
[mros2_reasoner_node-1]   File "/home/jeroen/Thesis/pipeline_exemplar/build/mros2_reasoner/mros2_reasoner/ros_reasoner.py", line 130, in objective_action_callback
[mros2_reasoner_node-1]     self.remove_objective(old_objective.name)
[mros2_reasoner_node-1]   File "/home/jeroen/Thesis/pipeline_exemplar/build/mros2_reasoner/mros2_reasoner/reasoner.py", line 58, in remove_objective
[mros2_reasoner_node-1]     destroy_entity(old_fg_instance)
[mros2_reasoner_node-1]   File "/usr/local/lib/python3.10/dist-packages/owlready2/prop.py", line 986, in destroy_entity
[mros2_reasoner_node-1]     e.namespace.world.graph.destroy_entity(e.storid, destroyer, relation_updater, undoer_objs, undoer_datas)
[mros2_reasoner_node-1] AttributeError: 'NoneType' object has no attribute 'namespace'

[chcorbato]

When reporting "errors" and similar issues, it is important to provide information to understand the context of the issue and be able to reproduce it (for some issues that you plan to solve in a couple of days it may seem irrelevant, but when things take more time, even you, not to speak of other developers will greatly appreciate that info):

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