active_model_type_validator

ActiveModelTypeValidator

Provides two ActiveModel validators:

1. One to validate that an attribute is of the correct type. Multiple types are allowed.
2. One to validate the contents of an attribute by calling #valid? on it, performing the same job as ActiveRecord's validates_associated.

Installation

Add this line to your application's Gemfile:

gem 'active_model_type_validator'

And then execute:

$ bundle

Or install it yourself as:

$ gem install active_model_type_validator

Usage

The usage is fairly standard. The object_type validator takes one option :type which is either a type name (string, symbol or type) or an array of type names. The contents validator needs no options. Both take the standard options all validators do, except that object_type ignores the :allow_blank option (you should use :allow_nil if you need equivalent behavior).

Examples:

class MyClass
    include ActiveModel::Model
    include ActiveModel::Validations

    validates :string_field, object_type: { type: String }
    validates :integer_field, object_type: { type: Integer }
    validates :numeric_field, object_type: { type: [Integer, Float] }
    validates :object_field, contents: true, object_type: { type: ChildClass }

    attr_accessor :string_field
    attr_accessor :integer_field
    attr_accessor :numeric_field
    attr_accessor :object_field

    def initialize
        @string_field = 'my string'
        @integer_field = 42
        @numeric_field = 7
        @object_field = ChildClass.new
    end

end

The contents validator adds what's equivalent to ActiveModel's associated validator, passing if calling #valid? on the attribute returns true.

The object_type validator lets you test ActiveModel objects used in an API to make sure they contain objects of the expected types rather than something you aren't expecting. It fills in a gap I was annoyed by when I validate incoming API objects immediately upon receiving them and go no further if they fail validation.

Contributing

1. Fork it ( https://github.com/tknarr/active_model_type_validator/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request