Active Model Validates Intersection Of

A custom validation for Active Model that check if an array is included in another one.

Identical to the method validates_inclusion_of from ActiveModel but for array comparison.

Consider an User model that have some set of "default" permissions.

class User < ActiveRecord::Base
  DEFAULT_PERMISSION = ["read", "write", "share"]
  validates_intersection_of :permission, in: DEFAULT_PERMISSION
end

If you want to validate your user based on an array:

user = User.new(permission: ["read", "share"])
user.valid? #true

user = User.new(permission: ["read", "admin"])
user.valid? #false

This active model custom validation is for you!

Installation

Add this line to your application's Gemfile:

gem "active_model_validates_intersection_of"

And then execute:

$ bundle

Or install it yourself as:

$ gem install active_model_validates_intersection_of

If your framework doesn't auto require gems, don't forget to do it after require of active_model gem.

require "active_model"
require "active_model_validates_intersection_of"

Usage

Parameters

:in - Parameter is required. (Supports: Array, proc and lambda)
:within - Optional: A synonym(alias) for :in
:message - Optional: Specifies a custom error message

Validation

You can use the intersection validation in three differents ways: (Feel free to use what you liked more :))

class User < ActiveRecord::Base
  DEFAULT_PERMISSION = ["read", "write", "share"]

  # Using the alias validates_intersection_of
  validates_intersection_of :permission, in: DEFAULT_PERMISSION, message: "invalid permission"
  validates_intersection_of :permission, within: DEFAULT_PERMISSION, message: "invalid permission"

  # proc and lambda support
  validates_intersection_of :permission, in: proc { DEFAULT_PERMISSION }, message: "invalid permission"
  validates_intersection_of :permission, in: lambda { |l| DEFAULT_PERMISSION }, message: "invalid permission"

  # Using the validator explicit:
  validates_with ActiveModelValidatesIntersectionOf::Validator, attributes: [:permission], in: DEFAULT_PERMISSION
  validates_with ActiveModelValidatesIntersectionOf::Validator, attributes: [:permission], within: DEFAULT_PERMISSION

  #Using the validator implicit:
  validates :permission, intersection: { in: DEFAULT_PERMISSION, message: "invalid permission" }
  validates :permission, intersection: { within: DEFAULT_PERMISSION, message: "invalid permission" }

end

License

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

Contributing

First of all, thank you for wanting to help!

Fork it.
Create a feature branch - git checkout -b more_magic
Add tests and make your changes
Check if tests are ok - rake spec
Commit changes - git commit -am "Added more magic"
Push to Github - git push origin more_magic
Send a pull request! ❤️