Setup

• git clone
• bundle install

On the console

ModelWithKeyAndVersion = Struct.new(:cache_key, :cache_version)
model_1_cache_1 = ModelWithKeyAndVersion.new("model/1", "1")
model_1_cache_2 = ModelWithKeyAndVersion.new("model/1", "2")

Rails.cache.fetch(model_1_cache_1) { "woohoo" }
puts Rails.cache.read(model_1_cache_1) # => "woohoo"
puts Rails.cache.read(model_1_cache_2) # => "woohoo"

We expect different objects with a different cache_version to return different results.

In the View

bundle exec rake db:migrate
rails s

Then visit: http://localhost:3000/users

What does this page do? It creates an user object with name of "schneems" it renders a partial without cache, then renders the same partial twice with cache, note that the timestamp is exactly the same.

The view then modifies the object to have a name of "richard" and saves it. This should modify the cache_version. You can see the name change in the uncached partial render, however when the cache is used it displays "schneems" rather than "richard".

In short modifying an object does not appear to clear it's cache when using dalli.