Cache interactions with Pre-Check and Post-Check are entirely unknown

[wrgeorge1983]

It's possible they already act as desired, or could be made that way quite easily. It's also possible it'll take some real digging into.

Since Checks are sort of "sub-tasks":

• Do (or should) they require their own cache config?
• Do (or should) they inherit the cache config of the parent task?
• If the Parent is a setconfig call, it should ALWAYS invalidate any cache after a PreCheck and before a PostCheck.

Task Start -> Pre Check -> SetConfig -> Poison Cache -> Post Check

[wrgeorge1983]

It's also possible anything involving pre/post checks should NEVER use the cache?

[tbotnz]

Currently the pre & post checks are invoked as apart of the same job.
with the current code the following would behavior would occur.

• if caching is applied on parent job, caching will apply to the pre & post checks
• if no caching is applied on the parent job, no caching will apply to the pre & post checks

my thoughts on this are:

• existing solution is simple and probably good enough
• any attempts to change this would likely require refactoring the pre & post checks themselves