[WIP] Display descriptive error message when socket path too long

[jdavcs]

This should fix galaxyproject/galaxy#13982

Note: stderr=subprocess.PIPE is necessary to get a non-empty return value from Popen.communicate(). I'm not sure whether that may affect anything else. A galaxy runtime error will still be logged correctly.

[natefoo]

Thanks! Unfortunately, this causes problems with foreground mode (galaxy or galaxyctl start -f) since the process never detaches. I am not sure what the best option here is - we could check the length of the path ourselves, but that's not super portable. We could also test-create the socket in Gravity before starting supervisord.

[jdavcs]

Thanks! Unfortunately, this causes problems with foreground mode (galaxy or galaxyctl start -f) since the process never detaches. I am not sure what the best option here is - we could check the length of the path ourselves, but that's not super portable. We could also test-create the socket in Gravity before starting supervisord.

Yeah, that's what I was afraid of. Maybe test-create the socket first? (I thought about checking the path - but, as you said, not portable and we'd have to be conservative (103? 92 max?), so there could be many false positives)

[jdavcs]

@natefoo maybe something like this? (provided I fix what it's currently breaking). Or do you think we should implement what you proposed here?

Also, should we push bump to 22.09?

[natefoo]

It looks like this method is called any time the class is instantiated, so supervisord may be running and that would make this unsafe?

[jdavcs]

you're right - this is a no-go.