Move cache factory functionality into the cache backend classes.

[gergelypolonkai]

This is a partial solution to #213

[coveralls]

Coverage decreased (-0.009%) to 79.27% when pulling d6c43b5 on gergelypolonkai:remove-init-functions into b5fa578 on sh4nks:master.

[sh4nks]

Looks good to me!

[ThiefMaster]

type(self).__module__ is breaking any application that subclasses this class since it will then resolve to the module where the subclass is. So I think this should remain as a hardcoded 'flask_caching.backends.' + import_me

[gergelypolonkai]

This line only runs if the cache backend you specify in your config (in CACHE_TYPE) doesn’t contain a dot (see line 218). If you define your own backend, it will be of the form your_package.your_module.YourClass, so import_me won’t be mangled for you.

[ThiefMaster]

i was more thinking about the built-in cache types. CACHE_TYPE = 'null' for example. Why would I ever want that to resolve to something different than the built-in one?

[gergelypolonkai]

In that case, null gets expanded to flask_caching.backends.null; self.module is always flask_caching in this context; itʼs written this way so even if we rename the whole module, we donʼt have to modify it here.

[ThiefMaster]

It isn't if you subclass the Caching class in your own module. Then it resolves to that one :/

[gergelypolonkai]

Ah, so thatʼs what you meant! Sorry for not getting it earlier.

Yes, you are right. I didnʼt consider that when writing the code because i couldnʼt imagine a use case for that. Unless you want to submit a fix, iʼll look into it later this week.