Miller

Write beautiful and descriptive code by adding configurable services with DSLs in a quick and easy manner.

Installation

Add this line to your application's Gemfile:

gem 'miller'

And then execute:

$ bundle

Or install it yourself as:

$ gem install miller

Usage

class ServiceBase
  include Miller.with(:name, :lastname)
  def full_name
    "#{name} #{lastname}"
  end
  # write your logic here
end

class Service < ServiceBase
  name 'John'
  lastname 'Doe'
end

Service.config.name # => 'John'
Service.config.lastname # => 'Doe'
inst = Service.new
inst.name # => 'John'
inst.lastname # => 'Doe'
inst.full_name # => 'John Doe'

IMPORTANT: Usually you will create a base class and then inherit from it for clarity as the previous example shows. The following examples are just to explain the features.

Blocks

  class Service
    include Miller.with(:name, :lastname)
    name { another_name }
    lastname 'Doe'

    def another_name
      "victor"
    end
  end
  Service.config.name # => Proc
  Service.config.lastname # => 'Doe'
  inst = Service.new
  inst.name # => 'victor'
  inst.lastname # => 'Doe'

Default Config

  class Service
    include Miller.with(:name, :lastname, default_config: { name: 'Henry', lastname: 'Miller' })
    lastname 'Doe'
  end
  Service.config.name # => 'Henry'
  Service.config.lastname # => 'Doe'
  inst = Service.new
  inst.name # => 'Henry'
  inst.lastname # => 'Doe'

Inheritance

If you require configs to be inherited by children use the following.

  class ServiceBase < Miller.base(:name, :lastname)
    name 'John'
    lastname 'Doe'
  end
  class Service < ServiceBase; end
  Service.config.name # => 'John'
  Service.config.lastname # => 'Doe'
  inst = Service.new
  inst.name # => 'John'
  inst.lastname # => 'Doe'

Override at instance level

WARNING: This can be useful but very dangerous please use it carefully.

  class Service
    include Miller.with(:name, :lastname)
    name 'John'
    lastname 'Doe'
  end
  Service.config.name # => 'John'
  Service.config.lastname # => 'Doe'
  inst = Service.new
  inst.name = 'Henry'
  inst.name # => 'Henry'
  inst.lastname # => 'Doe'

  class Service
    include Miller.with(:name, :lastname)
    name 'John'
    lastname 'Doe'
    def another_name
      'Martha'
    end
  end
  Service.config.name # => 'John'
  Service.config.lastname # => 'Doe'
  inst = Service.new
  inst.name = proc { another_name }
  inst.name # => 'Martha'
  inst.lastname # => 'Doe'

Errors

  class Service
    include Miller.with(:name, :lastname)
    name 'John'
    lastname 'Doe'
  end
  Service.config.foo # => Miller::ConfigNotSetError

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]/miller. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.