flood's handling of pool lifetimes/data scoping

[Aaron Bannert <aa...@clove.org>]

I've been thinking about how to handle data lifetime scoping in
flood and have come up with a solution, but I want some feedback
before I jump in and do it.

Theoretically, one instance of flood might need data that is scoped
at each of the following lifetimes:

all farms
each farm
all farmers
each farmer
all profiles
each profile

and possibly also:
each use of a urllist
each url in a urllist

and maybe even:
each flood (global per-process level)


Potentially, a lower-level iterator like a profile may want to store
data at a higher level like a farm. I don't see it working the other way
around, since farms don't know much about their farmers other than when
they start and stop. So the question is: How do the lower-level iterators
get access to the higher-level scopes (aka pools)? Since we'll always have
this hierarchy, perhaps we can take advantage of that somehow to allow
a lower level access to it's "parent's" pool? Ideas?

-aaron