module ActiveSupport::Cache

def expand_cache_key(key, namespace = nil)

The +key+ argument can also respond to +cache_key+ or +to_param+.

ActiveSupport::Cache.expand_cache_key([:foo, :bar], "namespace") # => "namespace/foo/bar"
ActiveSupport::Cache.expand_cache_key([:foo, :bar]) # => "foo/bar"

concatenated into a single key. For example:
each of elements in the array will be turned into parameters/keys and
If the +key+ argument provided is an array, or responds to +to_a+, then

scoped within that namespace.
cache store. Optionally accepts a namespace, and all keys will be
Expands out the +key+ argument into a key that can be used for the

def expand_cache_key(key, namespace = nil)
  expanded_cache_key = namespace ? +"#{namespace}/" : +""
  if prefix = ENV["RAILS_CACHE_ID"] || ENV["RAILS_APP_VERSION"]
    expanded_cache_key << "#{prefix}/"
  end
  expanded_cache_key << retrieve_cache_key(key)
  expanded_cache_key
end

def lookup_store(store = nil, *parameters)

# => returns MyOwnCacheStore.new
ActiveSupport::Cache.lookup_store(MyOwnCacheStore.new)

If the first argument is not a Symbol, then it will simply be returned:

# => same as: ActiveSupport::Cache::FileStore.new('/tmp/cache')
ActiveSupport::Cache.lookup_store(:file_store, '/tmp/cache')

class's constructor:
Any additional arguments will be passed to the corresponding cache store

# => returns a new ActiveSupport::Cache::MemCacheStore object
ActiveSupport::Cache.lookup_store(:mem_cache_store)

# => returns a new ActiveSupport::Cache::MemoryStore object
ActiveSupport::Cache.lookup_store(:memory_store)

For example:
store class under the ActiveSupport::Cache namespace will be created.
If you pass a Symbol as the first argument, then a corresponding cache

ActiveSupport::Cache::MemoryStore object will be returned.
If no arguments are passed to this method, then a new

Creates a new Store object according to the given options.

def lookup_store(store = nil, *parameters)
  case store
  when Symbol
    options = parameters.extract_options!
    # clean this up once Ruby 2.7 support is dropped
    # see https://github.com/rails/rails/pull/41522#discussion_r581186602
    if options.empty?
      retrieve_store_class(store).new(*parameters)
    else
      retrieve_store_class(store).new(*parameters, **options)
    end
  when Array
    lookup_store(*store)
  when nil
    ActiveSupport::Cache::MemoryStore.new
  else
    store
  end
end

def retrieve_cache_key(key)

def retrieve_cache_key(key)
  case
  when key.respond_to?(:cache_key_with_version) then key.cache_key_with_version
  when key.respond_to?(:cache_key)              then key.cache_key
  when key.is_a?(Array)                         then key.map { |element| retrieve_cache_key(element) }.to_param
  when key.respond_to?(:to_a)                   then retrieve_cache_key(key.to_a)
  else                                               key.to_param
  end.to_s
end

def retrieve_store_class(store)

Raises an error when the store class cannot be found.
Obtains the specified cache store class, given the name of the +store+.

def retrieve_store_class(store)
  # require_relative cannot be used here because the class might be
  # provided by another gem, like redis-activesupport for example.
  require "active_support/cache/#{store}"
rescue LoadError => e
  raise "Could not find cache store adapter for #{store} (#{e})"
else
  ActiveSupport::Cache.const_get(store.to_s.camelize)
end

Modules

Classes