A stab at using RequestStore (https://github.com/steveklabnik/request_store) as a rails Cache::Store

request_cache_store.rb

class RequestCacheStore < ActiveSupport::Cache::Store

  # Delete all entries with keys matching the pattern.
  #
  # Options are passed to the underlying cache implementation.
  #
  # All implementations may not support this method.
  def delete_matched(matcher, options = nil)
    options = merged_options(options)
    instrument(:delete_matched, matcher.inspect) do
      matcher = key_matcher(matcher, options)
      RequestStore.keys.each do |key|
        delete_entry(key, options) if key.match(matcher)
      end
    end
  end

  # Increment an integer value in the cache.
  #
  # Options are passed to the underlying cache implementation.
  #
  # All implementations may not support this method.
  def increment(name, amount = 1, options = nil)
    options = merged_options(options)
    if num = read(name, options)
      num = num.to_i + amount
      write(name, num, options)
      num
    else
      nil
    end
  end

  # Decrement an integer value in the cache.
  #
  # Options are passed to the underlying cache implementation.
  #
  # All implementations may not support this method.
  def decrement(name, amount = 1, options = nil)
    options = merged_options(options)
    if num = read(name, options)
      num = num.to_i - amount
      write(name, num, options)
      num
    else
      nil
    end
  end

  # Cleanup the cache by removing expired entries.
  #
  # Options are passed to the underlying cache implementation.
  #
  # All implementations may not support this method.
  def cleanup(options = nil)
    options = merged_options(options)
    RequestStore.store.keys.each do |key|
      entry = RequestStore.store[key]
      delete_entry(key, options) if entry && entry.expired?
    end
  end

  # Clear the entire cache. Be careful with this method since it could
  # affect other processes if shared cache is being used.
  #
  # Options are passed to the underlying cache implementation.
  #
  # All implementations may not support this method.
  def clear(options = nil)
    RequestStore.clear!
  end

  protected

  # Read an entry from the cache implementation. Subclasses must implement
  # this method.
  def read_entry(key, options) # :nodoc:
    RequestStore.store[key]
  end

  # Write an entry to the cache implementation. Subclasses must implement
  # this method.
  def write_entry(key, entry, options) # :nodoc:
    RequestStore.store[key] = entry
  end

  # Delete an entry from the cache implementation. Subclasses must
  # implement this method.
  def delete_entry(key, options) # :nodoc:
    RequestStore.store.delete(key)
  end

end