ActionKit

Action kit is a bunch of patterns I've used around the excellent interactor gem.

This is currently half-baked as its just being extracted from projects. Hopefully I will find some time to make it more robust.

Installation

Add this line to your application's Gemfile:

gem 'action_kit', github: 'robhurring/action_kit'

And then execute:

$ bundle

Or install it yourself as:

$ gem install action_kit

Usage

Basic Context Contracts

Action provides very basic input/output contracts by checking that the context has the proper expects keys set, and returns the proper promises keys on successful runs.

# app/actions/login_user.rb
class LoginUser
  include Action

  expects :username, :password
  promises :logged_in

  def call
    if User.login(username, password)
      context.logged_in = true
    else
      context.fail!
    end
  end

  private

  delegate :username, :password, to: :context
end

Basic Caching

ActionCache provides basic interactor result caching.

Caching defaults to using Marshal as its serializer to keep complex objects safe -- this can be swapped out by changing ActionCache.serializer to anything that implements #dump and #load (see: ActionCache::Serializer::Marshal)
To swap out the cache you can change ActionCache.cache to any object that implements #fetch(key, options, &block) (see: ActionCache::Cache::Worthless)

NOTE: This only caches successful calls. If context.failure? is true then no caching will take place.

WARNING: Merging OpenStruct contexts is tricky and not one-size-fits-all (at least not yet). Have a look at the context merging strategies to see what can work. The default is paranoid and only sets new keys on the context instead of overwriting anything.

# config/initializers/action_kit
ActionKit::ActionCache.cache = Rails.cache
ActionKit::ActionCache.logger = Rails.logger
ActionKit::ActionCache.enabled = !Rails.env.test?

# app/actions/get_user.rb
class GetUser
  include Action
  include ActionCache

  cache_key do |context|
    %(users:#{context.username})
  end

  expires_in 1.hour

  expects :username
  promises :user

  def call
    response = api.get(username)

    if response.success?
      context.user = response.user
    else
      context.fail!(error: response.error)
    end
  end

  private

  delegate :username, to: :context

  def api
    Company::API::Users
  end
end

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake rspec 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. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/[USERNAME]/action_kit. 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.

License

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

robhurring / action_kit