OnKillRun feature

[decanus]

A helper to run a function if a command is killed.

[CLAassistant]

All committers have signed the CLA.

[marckhouzam]

Cool idea @decanus !
I haven't tried it out yet but it looks useful.
This will need some tests and documentation.
cc @jpmcb

[talbright]

This is a good idea...we had to implement this outside of cobra (which is fine.) But I think this establishes a good practice that all CLI's should have OOB. Some lint issues to clean up, at a quick glance it should be safe to annotate out SA1017. Not sure about the others...

[marckhouzam]

@decanus Sorry for the delay. Can you rebase this to make CI pass?

[decanus]

@marckhouzam done!

[marckhouzam]

This is really great @decanus ! I love it!
I would like to include it in the next release of Cobra.

Would you be able to add a small paragraph of documentation after this section https://github.com/spf13/cobra/blob/main/site/content/user_guide.md#prerun-and-postrun-hooks

And a unit test would be important to make sure this does not break in the future.

Finally, there are a couple of linter errors to fix.

Thanks a lot!

[marckhouzam]

I was thinking about how this new feature would be used. I like the fact that the OnKillRun can be defined for a specific command. But what if I wanted to create a global OnKillRun for all the commands? For example to always intercept ^C?

Would that be a likely scenario?

[marckhouzam]

@decanus Are you still interested in getting this merged?

[marckhouzam]

I think we also need os.Interrupt for things to work on Windows

[prochac]

They seem to be supported for Windows, yet use of syscall package can be tricky for cross-platform Go.
/usr/lib/go/src/syscall/types_windows.go

[rojer]

found this through google - would be nice to get this finished and merged, but i guess for now i'll have to roll my own signal handler

[marckhouzam]

I'm still interested in merging this @decanus but CI is failing.
Also, a very small doc and test would be important.