This is supported in Rails 7.1+

rails/rails#49100

Also note:

enum something: { ... }

is now deprecated: rails/rails#50987

and

enum :something, { ... }, validate: true

should be used

EnumAttributesValidation

Enum Attributes Validation provides validation functionality for enum attributes in models. It validates inclusion for the specified enum keys. If values are nil the record is saved.

Installation

Add to Gemfile:

gem 'enum_attributes_validation'

And then execute:

$ bundle

Or install it yourself as:

$ gem install enum_attributes_validation

Usage

Use built in method to specify which enum attributes you want to validate.

class Dog < ApplicationRecord
  enum gender: { male: 0, female: 1 }
  enum hair_color: { brown: 0, black: 1, blonde: 2 }

  validate_enum_attributes :gender, :hair_color
end

dog = Dog.new(hair_color: :brown, gender: :female)
dog.save
# => <Dog gender: "female", hair_color: "brown" >

dog = Dog.new
dog.save
# => <Dog gender: nil, hair_color: nil >

dog = Dog.new(hair_color: nil, gender: nil)
dog.save
# => <Dog gender: nil, hair_color: nil >

Or use the singular method.

class Dog < ApplicationRecord
  enum gender: { male: 0, female: 1 }
  enum hair_color: { brown: 0, black: 1, blonde: 2 }

  validate_enum_attribute :gender
end

Custom error messages

To show a custom error message:

class Dog < ApplicationRecord
  enum gender: { male: 0, female: 1 }

  validate_enum_attribute :gender, message: "Some string msg..."
end

Translations

To use translations you need to update your locale file as follows

en:
  activerecord:
    errors:
      models:
        #your_model_name#:
          attributes:
            #your_attribute_name#::
              invalid_enum: "can't be %{value}. Valid values are: %{valid_values}"

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/CristiRazvi/enum_attributes_validation.

License

MIT License.