ActiveRecord::PGEnum

This gem is a small monkeypatch to ActiveRecord so that your schema.rb file can support PostgreSQL's native enumerated types.

This will allow you to use enum columns in your database without replacing schema.rb with structure.sql.

Version support

Currently only Rails 5.2 is supported. Support for previous versions going back to 4.1 are planned.

Installation

Add this line to your application's Gemfile:

gem 'activerecord-pg_enum'

And then execute:

$ bundle

Or install it yourself as:

$ gem install activerecord-pg_enum

Usage

Migrations

Defining a new ENUM

class AddContactMethodType < ActiveRecord::Migration[5.2]
  def up
    create_enum "contact_method_type", %w[Email Phone]
  end

  def down
    drop_enum "contact_method_type"
  end
end

Adding a value to an existing ENUM

class AddSMSToContactMethodType < ActiveRecord::Migration[5.2]
  def up
    add_enum_value "contact_method_type", "SMS", before: "Phone"
  end

  def down
    raise ActiveRecord::IrreversibleMigration
  end
end

Helper Methods

class ContactInfo < ActiveRecord::Base
  include ActiveRecord::PGEnum::Helper

  pg_enum contact_method: %w[Email SMS Phone]
end

pg_enum is a wrapper around the official enum method that converts array syntax into strings. The above example is equivalent to:

class ContactInfo < ActiveRecord::Base
  include ActiveRecord::PGEnum::Helper

  enum contact_method: { Email: "Email", SMS: "SMS", Phone: "Phone" }
end

There's no technical reason why you couldn't detect enum columns at startup time and automatically do this wireup, but I feel that the benefit of self-documenting outweighs the convenience.

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/getflywheel/activerecord-pg_enum.

License

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