Rails 2.3.8 Action Caching without layout (ajax and non-ajax requests)

rubyonrails-talk
1

Hi there,

I'm using Action Caching with Rails 2.3.8 on Heroku with Memcached (via Dalli Gem).

Without the layout parameter Action Caching works fine. However, as soon as I add layout => false I get problems: Normal non-ajax requests are cached fine, without the layout, as expected. But ajax requests are not properly cached: I get cache misses all the time. Then, when I log in to my app neither normal, nor ajax requests are cached at all.

I also tried to set :layout => Proc.new { |c| c.request.xhr? } When I do that ajax and normal requests are properly cached (no matter if logged out or logged in) but normal requests also cache the layout. Seems odd to me as normal requests should have :layout => false. I'm trying to debug this for hours now, but I haven't got a clue what's going on so far. What especially confuses me is that the logged in state of my app apparently has an influence on the caching behaviour.

Here is my full caching call (for the case of layout => false):

[code]caches_action :index, :layout => false,                       :cache_path => Proc.new { |c| c.params.clone.delete_if { |k,v| ['authenticity_token'].include? (k) }.merge(:xhr => c.request.xhr? ? 't' : 'f') }[/code]

I'd greatly appreciate any help on this!

Nico

2

Okay, I debugged a bit more and found out what the problem is (at least when locally in development environment). Inside the action cache content_for_layout is called to get the content to be cached if layout is set to false. This causes my ajax requests to be not cached because content_for_layout returns nil as I don't render the layout with ajax calls, only a partial. So I do need to set layout to true for ajax calls. However I can't do that the way I tried to, as the layout param doesn't accept a Proc. So I overwrote part of the ActionCacheFilter class to test the layout for a call method and call it if present. That works great locally! However, in production on Heroku with Memcached it still won't work properly. Ajax calls are not cached.

3

Okay, works fine now! I slightly changed the way I overwrote the ActionCacheFilter.