Here is yet another implementation for Grape cache. This implementation based on middlewares, a standard extension interface of Grape. Response body cached effectively on response status 200 in a format of API.

Add this line to your application's Gemfile:

gem 'another_grape_cache'

And then execute:

$ bundle

Or install it yourself as:

$ gem install another_grape_cache

    # config/another_grape_cache.rb
    
    AnotherGrapeCache.configure do |config|
      config.cache_backend = Rails.cache
      config.perform_caching = true
    end

• cache_backend - should implement a public interface of read/write/exists? as a standard Rails.cache
• perform_caching - toggles caching (might be disabled for dev)

    # app/api/posts/index_endpoint.rb
    
    include AnotherGrapeCache::CacheHelper

    helpers do
      def posts
        @posts ||= Post.limit(10)
      end
    end

    cache(max_age: 10.minutes, expires_in: 5.minutes, private_cache: true, cache_if: -> { rand(2) == 1 }) do
      posts.cache_key
    end
    
    get do
      present posts
    end

• max_age - ActiveSupport time range, max cache time for client. Max age set as directive of the HTTP header Cache-Control, default 0
• private_cache - Boolean, set private/public for the HTTP header Cache-Control, default false.
• expires_in - parameter for caching backend (max time to live).
• cache_if - a lambda which must return a Boolean value. The lambda is executed in the context of an endpoint
• block - should return a value for cache_key. This block is executed inside a route context, helpers are available there

Cache hit/miss status exposed as a HTTP header X-Cache-Status: MISS/HIT

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install.

Bug reports and pull requests are welcome on GitHub at https://github.com/SamMolokanov/another_grape_cache. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

The gem is available as open source under the terms of the MIT License.

Everyone interacting in the AnotherGrapeCache project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.