I was using rclpy.spinuntilfuture_complete to wait for an async service call to finish and this worked for a while but at some point it started causing my node to stop spinning permanently. I found some github issues that say explicitly that rclpy does not support calling spin recursively because it doesn't support re-entrant calls.

This is kind of unfortunate for my use case since I'll have to use a Multithreaded executor now, but I guess I struggle to understand when you would ever need to call rclpy.spinuntilfuture_complete if you weren't already inside of some kind of ROS callback.