Didit - Simple Ruby Dependency Injection

Didit is a tiny gem that gives you a simple dependency injection mechanism with package scanning for the Ruby programming language. It extends the base class "Object" with a number of operation you can use to decorate your classes with.

To create a class that is a service one could do the following:

class MyService
    as_service
end

Now, when the ServiceScan runs and loads the ruby file, it will recognize this class a service and registers it for safe keeping. Any service is able to inject other services, or a list of services of a certain type. To inject MyService into another service do the following:

class AnotherService
     as_service
     inject :my_service
end

This will automatically generate a method called 'my_service' that returns the one instance to our MyService class. It is also possible to get a list of certain service objects:

class BaseService; end
class A < BaseService; as_service; end
class B < BaseService; as_service; end;

class AnotherService
    as_service
    inject_list BaseService, as: "service_list"
end

Now, in your methods you can us the 'service_list' method to retrieve an array of available BaseService implementations.

Finally, it is possible to run code after the service has been initialized and all the injectables have been setup properly. To do this, specify a method that is ran post_construct, like so:

class AnotherService
    as_service

    post_construct :after_init

    def after_init
        puts "Run afterwards"
    end
end