Exciting incoming addition to GetPaid: credits

Last week, we peered into the top secret skunkworks of dixond and well, let the cat out of the bag about an exciting new extension coming to GetPaid any day now :) Ok, so maybe skunkworks is a bit of exageration...but I deal with developers who are hard to get to talk! It is often classified (in heads) until checked in...thanks to a shocking burst of verbosity, we got this insight:

(12:04:11 AM) dixond: effectively what I've built is a way to turn a Plone site with GetPaid into an advertising channel, where people can pay to publish their content for a fixed time. The basic framework and concept can be extended then to other things also.

Stepping down from dixond's elloquent marketing-speak, the use case is something like this: A user needs some credit to make their content public in some way (ie "for a week" or by virtue of a group membership).

OK, the nuts and bolts:
1) ICreditRegistry for storing the credits (can obviously be in RDBMS but my trivial implementation uses ZODB and BTrees)
2) TickingMachine subscriber that knows about ICreditPublishedContent and applies some rules around send reminder emails, depublish, etc
3) Archetypes schema extender profile for ICreditPublishedContent to track stuff like 'weeks remaining published'
4) Various portlets to allow purchasing credit and using that credit to publish ICreditPublishedContent
5) A few basic content types to represent the credit being purchased

Basically, what I've been building is a way to buy 'non-things' much like the notion of the 'donatable' type and to keep track of them and then use them for controlling access to arbitrary actions later. At present it works great, I'm spending most of my time 'generic-ifying' it so that it can be re-used elsewhere and isn't tied too closely to my specific use-case. Also on the list are other credit types like 'group membership' etc. Once I've generic-ified it enough this should be 'easy'.

Currently, three packages: getpaid.creditpublish, getpaid.creditregistry, getpaid.purchasablecredit

Future extensions could also allow content to be accessed by using credits, if a payment processor is implemented which consumes credits.

What are others saying: "that's a really needed usecase of getpaid - lots of people will be hopping happy :)" -duffyd on #getpaid