Setting and deleting cache in Django with tags

The Django cache system is real help when you need to keep your site as fast as possible. It offers multiple back-ends and is super easy to get started using. I just wish it had the ability to tag content when you are setting it in the cache. If you could do that then you could do bulk deleting of content based on tags. One use-case that comes up again and again for me is caching paginated results. If you have blog-entry1-page1 and blog-entry1-page2 both stored in the cache and want to delete them when a new entry is added what do you do? It’s hard if not impossible you know which paged set is currently in cache and we need to know the keys in order to delete them.

I searched and searched for a solution to this problem with not much help from google. I did find this post by Eric Florenzano which is close to the approach I took, but I wanted something more generic. So I decided to add two new methods cache.set_with_tags and cache.delete_by_tags to whatever cache backend you are using. Just to note this is only useful if you intend to utilize the low-level cache framework.

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