LifeCycle pattern dosn't work (for me at least)

[DrShIkIgAmy]

Here's the problem:
I have LifeCycleNode implemented as component. The node has to received some data from a service to pass Configuration state. I bet you've already got the point. The configuration func is deadlocked. Because I can't return control to a component_container, cause configuration is not finished. I can't finish configuration, cause I've not received the data from the service (stiil awaiting). To receive response some of spins has to be called, but I can't do this, because my node will be double-registrated in that case. I cannot create another node (for client purpose) and destroy it after response is received, because any new node inside component derive name from parent. I cannot create sub-node, cause my node is derived from LifeCycleNode.
May be messed up a little bit, but it seems to me, that is is a bug.

[fujitatomoya]

@DrShIkIgAmy thanks for creating issue, but i am not really sure about the case that you described. could you provide self-contained reproducible sample to this problem you have?

[tgroechel]

If I'm parsing this correctly @DrShIkIgAmy , are you referring to the deadlock issue of calling a service within a running callback? I.e., #773

Issue is:

• on_change_state calls a user callback (e.g., on_configure)
• within on_configure you call an external service
• the lc executor is stuck servicing this on_configure and can therefor not process any response (i.e., deadlocked)

This is likely addressed by #2213

[fujitatomoya]

@tgroechel thanks for the info, #773 (comment) could be something we can do right now in the application.

[ros-discourse]

This issue has been mentioned on ROS Discourse. There might be relevant details there:

https://discourse.ros.org/t/deferrable-canceleable-lifecycle-transitions/32318/1