Support for deadline on subscribers

[rdelfin]

I'm currently working on a ROS node that requires use of the subscriber node feature. While I can see there's a method for setting the deadline, I can't find a way of setting up a callback, similar to the deadline_callback option you can set in rclcpp. Is there an equivalent, or plan to add support for this feature?

[rdelfin]

If there is no plan I'm looking into making a PR for this. Doesn't look too complicated, but I'm sure I'll come to regret saying that

[m-dahl]

You are right, there is no mechanism like this implemented, and I have no plans to add it anytime soon. Feel free to make a PR, I will support best I can. If the functionality is exposed in rcl it shouldn't be too much work I think.