DCI and Ruby

What is DCI and how can we use it with Ruby?

Transcript

1. DCI and Ruby
2. What is DCI? Trygve Reenskaug (MVC, UML) Data, context and interaction OOP paradigm Goals Improve readability Separation of code System state instead of object state End user style of thinking
4. Theatre Director Actors Scene Roles
5. Data “What the system is” - Actor Simple object Basic functionality / no interaction with other objects Object thinking instead of class thinking
6. Context “How the system looks and starts” - Director Represents one or more use cases Identify objects and assign them roles at runtime Use case functionality = data objects with assigned roles combined
7. Interaction “What the system does” - Role Roles played by objects Stateless call methods on self (= playing object) Interactions are generic
9. Example Waitress Complex Model (my waitress, employee, person in restaurant) Placing an order CustomerOrdersMeal Object Actors: Customer, Waitress Extend Customer with Consumer and Waitress with MenuCard and OrderManager Call waitress.order_meal(customer, meal)
10. Conflict or Complementary? Fat Model? MVC / Model2? REST? Ruby? Rails?
11. DCI in Rails Data => ActiveRecord Model Context => Controller action or separate workflow class Roles => Module to mix in
12. Sources http://en.wikipedia.org/wiki/Data,_Context,_and_Interaction http://andrzejonsoftware.blogspot.com http://nicksda.apotomo.de/2011/12/ruby-on-rest-2- representers-and-the-dci-pattern/ http://mikepackdev.com/blog_posts/24-the-right-way-to- code-dci-in-ruby
13. Learn more... http://www.leansoftwarearchitecture.com/ http://vimeo.com/8235394