Never Cache *preview* blog entries

[jefftriplett]

One pain point we run into when sharing draft blog entries is that someone will spot a typo, and then we have to add an extra query string to the URL to bust the cache.

In theory, marking this as never cache could save us some headaches.

[thibaudcolas]

That’d be great! I’ve marked this as a bug as I can’t see how caching drafts can ever be a good thing.

[thibaudcolas]

Chatting about this with @bmispelon, this should be relatively simple. The caching is done in our reverse proxy layer (Fastly), which respects cache-related headers. So we’d need to make sure the view that serves blog entries sets that header when the blog entries are unpublished.

And add tests to make sure this is working as expected (cache off when serving live blog content, off when serving drafts).