Rails rendering extension for server-side html caching

Why do I need this?

To improve fragment caching efficiency in Rails by only caching the things that change. CacheRocket may be used in with other Rails caching strategies such as Russian Doll caching.

Install

Add this line to your Gemfile:

gem 'cache_rocket'

Add this line to a helper file, likely your ApplicationHelper:

include CacheRocket

Use

This gem allows you to cache a partial of static html and replace inner dynamic html. Here is an example scenario:

You have some html that you would like to cache, but cannot because of some uncacheable code nested in the DOM. For example:

file.html.haml:

= render 'container'

_container.html.haml:

.lots
  .of
    .htmls
      = render 'dynamic'

_dynamic.html.haml:

= complicated_uncacheable_stuff

In the scenario above, you can't cache anything. With cache_rocket, you can:

file.html.haml:

= render_cached 'container', replace: 'dynamic'

_container.html.haml:

- cache "container" do
  .lots
    .of
      .htmls
        = cache_replace_key 'dynamic'

_dynamic.html.haml:

= complicated_uncacheable_stuff

In the above example, you could also remove the _dynamic.html.haml file like so:

file.html.haml:

= render_cached 'container', replace: { dynamic: complicated_uncacheable_stuff }

Options

render_cached provides several calling styles:

Single partial to replace

render_cached "container", replace: "inner"

Array of partials to replace

render_cached "container", replace: ["inner", "footer"]

Hash of keys to replace with values

render_cached "container", replace: { key_name: a_helper_method(object) }

Block containing a hash of keys to replace with values

render_cached "container" do
  { key_name: a_helper_method(object) }
end

Render a collection with hash of keys, using a Proc for each collection item

render_cached "container", collection: objects,
  replace: { key_name: ->(object){ a_helper_method(object) } }

Render a collection with block syntax

render_cached "container", collection: objects do
  { key_name: ->(object){ a_helper_method(object) } }
end

Contribute

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request