README.md

Object Context

Retrieve and relate objects within contexts. Provides dependency injection convenience inspired by the simplicity of Google's Guice.

Basic composition

Declare required component objects for a class using .construct_with

require 'conject'

class Wood
  def to_s; "Wood"; end
end

class Nails
  def to_s; "Nails"; end
end

class Fence
  construct_with :wood, :nails

  def to_s
    "I'm made of #{wood} and #{nails}"
  end
end

fence = Conject.default_object_context.get(:fence)
puts fence
#=> "I'm made of Wood and Nails"

Configuring objects

Call #configure_object or #configure_objects to configure one or more objects wrt their construction or handling.

• :cache [true|false] - Enable/disable object caching in context. If false, a new instance is created for every request for an object with the given name. Default true.
• :construct [Proc|Lambda] - Anonymous function to call to provide the named object. Will be cached like any other object, subject to :cache configuration for this context.

Eg. context.configure_objects({ :wood => { :cache => false }, :nails => { :construct => lambda do "The nails" end}, }) # context[:wood] != context[:wood] # context[:nails] == "The nails"

Modules as namespaces

module Chart
  class Presenter
    construct_with 'chart/model', 'chart/view'

    def to_s
      "I'm a Chart::Presenter composed of a #{model} and a #{view}"
    end
  end
end

Subcontexts

first_fence = nil
second_fence = nil

Conject.default_object_context.in_subcontext do |sub|
  first_fence = sub[:fence]
end

Conject.default_object_context.in_subcontext do |sub|
  second_fence = sub[:fence]
end

# second_fence != first_fence