Designing a cache key calculating strategy that's manageable

Question

I am having trouble managing cache keys in my project.

Currently we use a define-at-wish strategy and uniqueness of keys are not guaranteed.

Every time some one want to cache a kind of object, a constant is defined in the module in a form like this:

BOOK_NOTE_KEY = "BKNT%d"

An BookNote object's cache key is like BOOK_NOTE_KEY % note.id.

I think this is not a good way, because cache keys are not manageable.

What strategy do you take in your projects?

Answer 1

You could use the full class name as a prefix/postfix. e.g. "YourNamespace.SubNamespace.BookNote.%d"

Or you could just generate a GUID for every class and use that as a prefix/postfix.

Answer 2

If you keep track of the last update time for each record (arguably a good practice anyway), then you can compose cache keys like:

BookNote/[id]-[last_updated]