Lotus.rb

An introduction to Lotus::Router, Lotus::Controller, and Lotus::View given at Sarma: Sarajevo Ruby meetup on 2014-03-20.

Transcript

2. Lotus is a full stack web framework for Ruby, built with lightness, performance and testability in mind. It aims to bring back OOP to web development, leveraging on stable APIs, a minimal DSL, and plain objects.
3. Does it replace Rails? Nope.
4. Philosophy • based on simplicity • less DSLs • few conventions • more objects • zero monkey-patching of the core language and standard lib • separation of concerns for MVC layers
5. Standalone frameworks • Lotus::Router • Lotus::Controller • Lotus::View
6. Release Strategy Release a component of the framework on the 23rd of every month
7. Lotus::Router Problem:
 No generic router for Ruby web apps
8. Lotus::Router require 'lotus-router' ! router = Lotus::Router.new do get '/hello', to: ->(env) { [200, {}, ['Hello, World!']] } get '/dashboard', to: 'dashboard#index' get '/middleware', to: RackMiddleware get '/rack-app', to: RackApp.new ! redirect '/legacy', to: '/' ! namespace 'admin' do get '/users', to: UsersController::Index end ! resources 'users' end ! Rack::Server.start app: app, Port: 2306
9. Lotus::Router require 'lotus-router' ! router = Lotus::Router.new do get '/hello', to: ->(env) { [200, {}, ['Hello, World!']] } get '/dashboard', to: 'dashboard#index' get '/middleware', to: RackMiddleware get '/rack-app', to: RackApp.new ! redirect '/legacy', to: '/' ! namespace 'admin' do get '/users', to: UsersController::Index end ! resources 'users' end ! Rack::Server.start app: app, Port: 2306
10. class Endpoint < Lotus::Routing::Endpoint def call(env) [200, {}, [super(params(env))]] end ! private def params(env) env.fetch('router.params') end end ! r = Lotus::Routing::EndpointResolver.new(endpoint: Endpoint) ! Application = Rack::Builder.new do app = Lotus::Router.new(resolver: r) do get '/' do 'Hello, World!' end ! get '/greet/:planet' do |params| "Hello from the #{ params[:planet] }!" end end run app end.to_app
11. class Endpoint < Lotus::Routing::Endpoint def call(env) [200, {}, [super(params(env))]] end ! private def params(env) env.fetch('router.params') end end ! r = Lotus::Routing::EndpointResolver.new(endpoint: Endpoint) ! Application = Rack::Builder.new do app = Lotus::Router.new(resolver: r) do get '/' do 'Hello, World!' end ! get '/greet/:planet' do |params| "Hello from the #{ params[:planet] }!" end end run app end.to_app
12. And now for something completely different
13. Lotus::Controller class Show include Lotus::Action ! def call(params) @article = Article.find params[:id] end end
14. But… Controller? class ArticlesController class Show include Lotus::Action ! def call(params) @article = Article.find params[:id] end end end
15. Or… class ArticlesController include Lotus::Controller ! action 'Index' do def call @articles = Article.all end end ! action 'Show' do def call(params) @article = Article.find params[:id] end end end
16. Featuring OOP • Single Responsibility Principle • Dependency Injection
17. DI in controllers class ArticlesController include Lotus::Controller ! action 'Index' do def initialize(repository = Article) @repository = repository end ! def call @articles = @repository.all end end end
18. No instance variables class ArticlesController include Lotus::Controller ! action 'Index' do expose :articles def initialize(repository = Article) @repository = repository end ! def call @articles = @repository.all end end end
19. Lotus::View class Index include Lotus::View ! def hi "Hi there, Sarma!" end end
20. and… Presenter! ! class ArticlePresenter include Lotus::Presenter ! def short_title title[0..15] end end
21. http://lotusrb.org/ http://lucaguidi.com/2014/01/28/building-sinatra-with- lotus.html