TypedModel

A Ruby library for defining data schemas via classes with typed fields and built in hydration and serialization

• data mapping (data -> object -> data)
• declared types
• declared validations
• Nested models

Installation

Add this line to your application's Gemfile:

gem 'typed_model'

And then execute:

$ bundle

Or install it yourself as:

$ gem install typed_model

Usage

Employee
  include ModelBase

  attribute :a_boolean, type: :boolean
  attribute :an_integer, type: :integer
  attribute :a_timestamp, type: :timestamp
  attribute :widget1, type: :map
  attribute :address, type: a_c
  attribute :addresses, seq_of: a_c
  attribute :colors, type: :seq
end

Sequences

  # non-empty/nil sequence
  attribute :a_seq, type: :seq, :validations [:required]
  
  attribute :a_seq, seq_of: :string
  
  attribute :a_seq, seq_of: Address
  
  # sequence of string -> integer maps
  attribute :a_Seq, seq_of: [:string, :integer]
  
  attribute :a_seq, seq_of: { type: Adress, :validations [:some_validation] }

Maps

  # string -> string
  attribute :a_map, :map_of [:string, :integer]
  
  attribute :a_map, type: :map, validations: [:required]
  
  # map of maps
  attribute :map_of_maps, :map_of [:string, [:string, :integer]]
  
  # map of maps
  attribute :a_map, :map_of [{type: :string, validators: [:some_check]},
                             {type: Address, validators: [:required]},
                    :validators [:required]

Validations

Primitive types (e.g. :string, :integer, :timestamp, :boolean, etc) are automatically validated.

Custom validations

Via :keyword or Validator instance

    class Employee
        ...
        attribute :name, validations: [:my_validation]

        def assert_my_validation(attr)
          add_error(attr, 'some error')
        end
     end
     

    validator = Validator.new(:foo) do
       ['some error']
    end
    
    class Employee
       ...
       attribute :name, validations: [validator]

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/[USERNAME]/typed_model.

License

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