liberation/redis-limpyd — pull request #11 by twidi (2012-06-12 08:36:49+00:00)
Title: Add fields for primary key management

Two fields:

* PKField: primary key field with free keys (user MUST set them, freely
(string, or int saved as string by redis)
* AutoPKField : auto-increment version of PKField

Some things to know:

* If no PKField defined for a model, a default AutiPKField, named `pk`
is created

* If a specific primary key is defined on a model, a subclass cannot
define another one.

* All stuff about setting & checking a primary key (including collection
of all primary keys of a model) is managed on the PKField, not on the
model (so a user can redefine the behaviour)

* It's not possible to update the pk field value of an instance