Ruby Object Mapper

Ruby Object Mapper is an implementation of the Data Mapper pattern in Ruby language. It consists of multiple loosely coupled pieces and uses a powerful relational algebra library called axiom.

Getting started

Currently the setup is a bit verbose. Automatization will come in the future once the API becomes stable.

gem install rom axiom-memory-adapter

1. Set up environment and define schema with mappings

  require 'rom'
  require 'axiom-memory-adapter'

  class User
    attr_reader :id, :name

    def initialize(attributes)
      @id, @name = attributes.values_at(:id, :name)
    end
  end

  env = ROM::Environment.setup(memory: 'memory://test') do
    schema do
      base_relation :users do
        repository :memory

        attribute :id,   Integer
        attribute :name, String

        key :id
      end
    end

    mapping do
      relation(:users) do
        map :id, :name
        model User
      end
    end
  end

2. Work with Plain Old Ruby Objects

  env.session do |session|
    user = session[:users].new(id: 1, name: 'Jane')
    session[:users].save(user)
    session.flush
  end

  jane = env[:users].restrict(name: 'Jane').one

Community

• #rom-rb channel on freenode
• Ruby Object Mapper mailing list

Authors

• Dan Kubb
• Markus Schirp
• Martin Gamsjaeger
• Piotr Solnica

License

See LICENSE file.