Add collection cache versioning

Cache versioning enables the same cache key to be reused when the object
being cached changes by moving the volatile part of the cache key out of
the cache key and into a version that is embedded in the cache entry.

This is already occurring when the object being cached is an
`ActiveRecord::Base`, but when caching an `ActiveRecord::Relation`
we are currently still putting the volatile information (max updated at
and count) as part of the cache key.

This PR moves the volatile part of the relations `cache_key` into the
`cache_version` to support recycling cache keys for
`ActiveRecord::Relation`s.

1 files changed, 4 insertions, 0 deletions

diff --git a/railties/lib/rails/application/configuration.rb b/railties/lib/rails/application/configuration.rb
index b79dbdbc6f..d743c1c0d9 100644
--- a/railties/lib/rails/application/configuration.rb
+++ b/railties/lib/rails/application/configuration.rb
@@ -142,6 +142,10 @@ module Rails
             active_storage.queues.analysis = :active_storage_analysis
             active_storage.queues.purge    = :active_storage_purge
           end
+
+          if respond_to?(:active_record)
+            active_record.collection_cache_versioning = true
+          end
         else
           raise "Unknown version #{target_version.to_s.inspect}"
         end