unique_item_attributes_validator

A simple validator to verify the uniqueness of certain attributes from a collection. Should be compatible with all latest Rubies.

Add this line to your application's Gemfile:

gem "unique_item_attributes_validator"

And then execute:

$ bundle

Or install it yourself as:

$ gem install unique_item_attributes_validator

Let's say you've got a simple hero model:

class Hero
  include ActiveModel::Validations

  attr_accessor :alter_ego, :name, :superpower

  def initialize(alter_ego:, name:, superpower:)
    @alter_ego = alter_ego
    @name = name
    @superpower = superpower
  end
end

And you want to form a super team with a collection of heroes. Then..

class SuperTeam
  include ActiveModel::Validations

  attr_accessor :heroes

  def initialize(heroes:)
    @heroes = heroes
  end
end

But the alter_ego and the name attributes must be unique for the heroes of this collection. So..

class SuperTeam
  include ActiveModel::Validations

  attr_accessor :heroes

  validates :heroes, unique_item_attributes: [:alter_ego, :name] #YAY!

  def initialize(heroes:)
    @heroes = heroes
  end
end

And that's pretty much it! 😁

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.

Bug reports and pull requests are welcome on GitHub at https://github.com/equalize-squad/unique_item_attributes_validator.

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