CacheAssociations

CacheAssociations is a simple cache implementation to make Low-Level caching collaborate with Association caching.

Installation

Add this line to your application's Gemfile:

gem 'cache_associations'

And then execute:

$ bundle

Or install it yourself as:

$ gem install cache_associations

Usage

class User < ApplicationRecord
  include CacheAssociations

  has_one :profile
  cache_association :profile do 
    # Put your cache name here
    # 
    # This is the default naming convention,
    # so if you follow the naming strategy,
    # you are free with providing the block
    [self.class.name, id, 'profile', update_at.to_i]
  end

  # you do not need to provide a block to specify the cache 
  # name, this will provide you a default name composed of  
  # [reflection.klass.name, send(reflection.foreign_key)]
  cache_global_association :profile

  def factorial_1000
    (1..1000).inject(:*)
  end
  cache_method :factorial_1000 # use cached_factorial_1000
end

class Profile < ApplicationRecord
  belongs_to :user, touch: true
end

The cache_association defines a method cached_profile to fetch data from the cache store. You may also specify additional options via the options argument, it's the same as ActiveSupport::Cache::Store#fetch, such as setting :expires_in will set an expiration time on the cache. And cache_association accepts an optional block to define the cache name, it's [self.class.name, id, name, updated_at.to_i] in default.

You can use cache_method to cache something else, like attributes and methods.

irb> u = User.take
irb> u.cached_profile # fetch from the cache store
irb> u.profile # fetch the cached version
irb> u.profile.reload # refetch from the database
  Profile Load (1.4ms) SELECT  "profiles".* FROM "profiles" WHERE "profiles"."user_id" = $1 LIMIT $2  [["id", 1], ["LIMIT", 1]]
irb> u.clear_caching_on_association(:profile) # clear the cache

You may customize what the data you cached, the cached method accepts an optional block that determines how to cache data. But it will break the original association, so you should be careful with this feature.

irb> u = User.take
irb> u.cached_profile do "gotcha" end
=> "gotcha"
irb> u.profile # it breaks
(Object doesn't support #inspect)
=> 
irb> u.profile.reload # restore
  Profile Load (1.4ms) SELECT  "profiles".* FROM "profiles" WHERE "profiles"."user_id" = $1 LIMIT $2  [["id", 1], ["LIMIT", 1]]

Development

After checking out the repo, run bin/setup to install dependencies. 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/FX-HAO/cache_associations. 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.

Code of Conduct

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