Fried::Dependency

Easily define object dependencies and inject them

Installation

Add this line to your application's Gemfile:

gem "fried-dependency"

And then execute:

$ bundle

Or install it yourself as:

$ gem install fried-dependency

Usage

Define object dependencies:

class A
end

class B
end

class D
end

class C
  include Fried::Dependency::Schema

  dependency :a, A
  dependency :b, B

  def call
    puts a.inspect
    puts b.inspect
  end
end

c = C.new
c.call # Prints <A...> and  <B...>

c = C.new(a: D.new)
c.call # Prints <D...> and <B...>

You can also specify default values:

class A
end
class B
  attr_accessor :num

  def initialize(num)
    self.num = num
  end
end

class C
  include Fried::Dependency::Schema

  dependency :a, A, -> { 123 }
  # It optionally accepts `type` or `type` and `obj`.
  # - `type` is the class of the dependency (B in this case)
  # - `obj` is the instance being initialized (C.new in this case)
  dependency :b, B, ->(type, obj) { type.new(obj.a) }

  def call
    puts b.num.to_s
  end
end

c = C.new
c.call # Prints 123

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/Fire-Dragon-DoL/fried-dependency.