ActiveRecord::Relatives

This tool will help you find all the associations and their ids related with given model.

Installation

Add this line to your application's Gemfile:

gem 'activerecord-relatives'

And then execute:

$ bundle

Or install it yourself as:

$ gem install activerecord-relatives

Usage

This tool will find all ids related with given model. Let's say your models look something like this:

class User < ActiveRecord::Base
  has_many :comments
  has_many :posts
end

class Post < ActiveRecord::Base
  belongs_to :author, class_name: 'User'
end

class Comment < ActiveRecord::Base
  belongs_to :post
end

and your data looks like this:

user1 = User.create! #=> #<User id: 1>
post1 = Post.create(author: user1) #=> #<Post id: 1 ...>
post2 = Post.create(author: user1) #=> #<Post id: 2 ...>
Comment.create!(post: post1) #=> #<Comment id: 1 ...>

user2 = User.create! #=> #<User id: 2>
post3 = Post.create(author: user1) #=> #<Post id: 3 ...>
Comment.create!(post: post3) #=> #<Comment id: 3 ...>

then ActiveRecord::Relatives will return all ids which are somehow related for a given record:

ActiveRecord::Relatives.call(user1) # => { Post => [1, 2], Comment => [1] }

Requirements

In order to make this tool work you need to have your associations properly set

Usage examples

This tool can be handy for various tasks, like:

• removing records with all associations
• detecting data which has missing associations (like, after incomplete delete)
• analyzing dependencies
• detecting circular dependencies
• detecting out of sync objects (like, objects which are related with multiple users, but they shouldn't)
• detecting god models
• generating UML diagrams
• you name it :)

Removing records with all associations

ActiveRecord::Base.transaction do
  ActiveRecord::Relatives.call(user1).each do |model, data|
    model.unscoped.where(id: data.ids).delete_all
  end
end

Detecting out of sync objects

records_without_user = []
ActiveRecord::Relatives.call(User.all.unscoped).each do |model, data|
  records_without_user << model.unscoped.where.not(id: data.ids)
end

Analyzing dependencies

post_dependency = ActiveRecord::Relatives
  .call(user1)
  .dependencies
  .detect { |dependency| dependency.key?(Post) }
post_dependency.depends_on #=> [User, Image, ...]

Development

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. 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/samesystem/activerecord-relatives. 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 ActiveRecord::Relatives project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.