This marks a major step towards centralizing some of the "spec" logic
and creating a single access point for them. Because `ImageSpecFields`
are just alternative interfaces for defining and registering specs,
they can be accessed and overridden in the same manner as other specs
(like those used by template tags): via the spec registry.
Somewhere along the line, a change got merged that stopped using the
receivers module. This re-integrates it and moves changes made to the
old receivers (static methods on ImageSpecField) to them.
This new feature gives the user more control over *when* their images
are validated. Image cache backends are now exclusively for controlling
the *how*. This means you won't have to write a lot of code when you
just want to change one or the other.
Signals are now connected without specifying the class and non-IK
models are filtered out in the receivers. This is necessary because of
a bug with how Django handles abstract models.
Closes#126
While this change means users can no longer specify their own filenames,
changing a property of a processor, for example, will now result in a
new image. This solves a lot of the previous invalidation issues.
* matthewwithanm/whencontrol:
Rename cache_state_backend to image_cache_backend
Add NonValidatingCacheStateBackend
Some documentation
Only invalidate spec file if source changes
Rename DefaultCacheStateBackend
generate method (optionally) saves file
Rename force flag to force-revalidation
Add clear method for when future validation is unwanted
Commands for validating and invalidating the cache
Fix var name typo
Spec files now accessible through _ik attr
Remove unused import
First shot at cache state backend implementation
Conflicts:
imagekit/models/fields.py
