Stripping of caching headers prevents Rails stale?/ fresh_when method from working correctly

[endymonium]

Hi,

as all caching headers (HTTP_IF_MODIFIED_SINCE and HTTP_IF_NONE_MATCH) are stripped away in

rack-mini-profiler/lib/mini_profiler/profiler.rb

Line 275 in 334da48

env['HTTP_IF_MODIFIED_SINCE'] = ''

the internal Rails caching mechanism stops to work as intended.

Basically the stale? (http://apidock.com/rails/ActionController/Base/stale%3F) method will always return true. The result is the kind of odd behaviour, that the server regenerates the content, but correctly sets the return code to 304.

I wanted to use the mini profiler to check the impact of http caching in my application. I think this is especially an issue if you use the mini profiler also in production environments.

Jan

p.s. this discussion might also be interesting: rtomayko/rack-cache#24

[SamSaffron]

This is by design, only for profiled requests, it only impacts admins.

If we let caching through you don't get correct results.

[ryana]

This behavior is super unintuitive. I just wasted 3 hours on it. I posit that having this "by design" is a mistake. The profiler should be just that: a profiler. It's presence shouldn't force more work on the application server. If you're an admin, and you're looking at the mini-profiler output, then you're savvy enough to go into your Inspector panel and clear the cache when you want to force the server to perform the work.

[SamSaffron]

I am open to adding a config setting for this if you wish. PR welcome

[ryana]

Excellent! I'll whip something up.

[ryana]

Here you go! #96

[SamSaffron]

closing this cause we have a setting for disabling cache busting now