Question

是否有任何类型的before_filter等效项可以与Rails.cache.fetch一起使用？

我在运行多个构建的测试环境中使用memcached，并希望设置一种方法来根据全局级别的环境变量修改我的密钥，而不是每次调用Rails.cache.fetch。< / p>

如果有其他方法可以解决这个我目前尚未发现的问题，我愿意接受建议。

Answer 1

您可以使用namespace选项或设置环境变量RAILS_CACHE_ID RAILS_APP_VERSION来附加缓存键名称。

来自rails/activesupport/lib/active_support/cache.rb

  # Expands out the +key+ argument into a key that can be used for the
  # cache store. Optionally accepts a namespace, and all keys will be
  # scoped within that namespace.
  #
  # If the +key+ argument provided is an array, or responds to +to_a+, then
  # each of elements in the array will be turned into parameters/keys and
  # concatenated into a single key. For example:
  #
  #   expand_cache_key([:foo, :bar])               # => "foo/bar"
  #   expand_cache_key([:foo, :bar], "namespace")  # => "namespace/foo/bar"
  #
  # The +key+ argument can also respond to +cache_key+ or +to_param+.
  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

挂钩前的Rails.cache.fetch

1 个答案: