Hanami: because sometimes, you need to re-invent the wheel

Hanami is a modern web framework for Ruby. It’s a full-featued MVC framework with asset integration. What could it possibly have to offer over Rails? As it turns out, quite a bit: a lightweight framework, OOP, plain old Ruby and, above all, simplicity. Sometimes it is worth it to re-invent the wheel.

Presented at Utrecht.rb.

Transcript

2. What would you like to complain about? [ ] Too much magic [ ] Too much boilerplate source: @phillip_webb
3. What would you like to complain about? [ ✔ ] Too much magic [ ] Too much boilerplate source: @phillip_webb
4. ARJAN VAN DER GAAG (@AVDGAAG) HANAMI …because sometimes, you need to
 re-invent the wheel
5. ARJAN VAN DER GAAG arjanvandergaag.nl • @avdgaag • brightin
6. “Hanami is a Ruby MVC web framework comprised of many micro-libraries. It has a simple, stable API, a minimal DSL, and prioritises the use of plain objects over magical, over-complicated classes with too much responsibility.”
7. “The natural repercussion of using simple objects with clear responsibilities
 is more boilerplate code.”
8. ARJAN VAN DER GAAG (@AVDGAAG) CONTROLLER
9. ARJAN VAN DER GAAG (@AVDGAAG) class Create include Web::Action def call(params) # book = ... redirect_to routes.book_path(book.id) end end
10. ARJAN VAN DER GAAG (@AVDGAAG) class Create include Web::Action params do param :book do param :pages, type: Integer, size: 0..9999 param :title, presence: true end end def call(params) if params.valid? # ... end end end
11. ARJAN VAN DER GAAG (@AVDGAAG) MINIMAL INTERFACES
12. ARJAN VAN DER GAAG (@AVDGAAG) class Show include Web::Action expose :book def call(params) @book = BookRepository.find(params[:id]) end end
13. ARJAN VAN DER GAAG (@AVDGAAG) RSpec.describe Show do it 'is successful' do response = Show.new.call('id' => '1') expect(response[0]).to eql(200) end end
14. ARJAN VAN DER GAAG (@AVDGAAG) class Show include Web::Action expose :book def initialize(repository: BookRepository) @repository = repository end def call(params) @book = @repository.find(params[:id]) end end
15. ARJAN VAN DER GAAG (@AVDGAAG) RSpec.describe Show do it 'exposes the book found in the repository' do book = Book.new action = Show.new(repository: double(find: book)) action.call('id' => '1') expect(action.exposures[:book]).to be(book) end end
16. ARJAN VAN DER GAAG (@AVDGAAG) VIEW
17. ARJAN VAN DER GAAG (@AVDGAAG) class ApplicationController < ActionController::Base helper :all end
18. ARJAN VAN DER GAAG (@AVDGAAG) module Web::Views::Books class Index include Web::View end end
19. ARJAN VAN DER GAAG (@AVDGAAG) module Web::Views::Books class Index include Web::View def render 'hello, world' end end end
20. ARJAN VAN DER GAAG (@AVDGAAG) module Web::Views::Books class Index include Web::View include MyHelper end end
21. ARJAN VAN DER GAAG (@AVDGAAG) module Web::Views::Books class Index include Web::View def books locals[:books] end end end
22. ARJAN VAN DER GAAG (@AVDGAAG) module Web::Views::Books class Index include Web::View def books locals[:books].map do |book| Web::Presenters::BookPresenter.new(book) end end end end
23. ARJAN VAN DER GAAG (@AVDGAAG) module Web::Presenters class BookPresenter include Hanami::Presenter def title super.upcase end end end
24. ARJAN VAN DER GAAG (@AVDGAAG) module Web::Presenters class BookPresenter include Hanami::Presenter def title super.upcase end end end book = Book.new(title: 'Pride & Prejudice') presenter = Web::Presenters::BookPresenter.new(book) presenter.title # => "PRIDE &AMP; PREJUDICE"
25. ARJAN VAN DER GAAG (@AVDGAAG) MODEL
26. ARJAN VAN DER GAAG (@AVDGAAG) class Book include Hanami::Entity attributes :title, :author, :pages end Book.new(title: '1984') # => #<Book @id=nil @title='1984' @author=nil
 # @pages=nil>
27. ARJAN VAN DER GAAG (@AVDGAAG) class BookRepository include Hanami::Repository end BookRepository.find(1) # => #<Book @id=1 @title="1984" @author="George # Orwell" @pages=1234> BookRepository.persist(Book.new(title: '1984')) # => #<Book @id=2 @title="1984" @author=nil # @pages=nil>
28. ARJAN VAN DER GAAG (@AVDGAAG) class AccountRepository include Hanami::Repository def self.find_by_username(username) query do where(username: username) end.first end end
29. ARJAN VAN DER GAAG (@AVDGAAG) MONOLITH FIRST
30. LIB APPS/WEB
31. LIB APPS/WEB APPS/API
32. LIB APPS/WEB APPS/ADMIN APPS/API
33. ARJAN VAN DER GAAG (@AVDGAAG) WASTE OF EFFORT TO RE- CREATE LOTS OF MOSTLY THE SAME TOOLS?
34. ARJAN VAN DER GAAG (@AVDGAAG) SOMETIMES, YOU NEED TO
 RE-INVENT THE WHEEL
35. “With large, ongoing software projects, a lot of the features that help with simple demo apps become irrelevant. Or worse, they become disadvantages and bottlenecks, and sometimes downright obstacles to any further development.” Filip Hracek, The ‘Hello World’ Fallacy
36. ARJAN VAN DER GAAG (@AVDGAAG) SIMPLICITY > CONVENIENCE
37. ARJAN VAN DER GAAG (@AVDGAAG) YOU’RE WRITING RUBY
38. What would you like to complain about? [ ✔ ] Too much magic [ ] Too much boilerplate source: @phillip_webb
39. ARJAN VAN DER GAAG (@AVDGAAG) SEE HANAMIRB.ORG
40. ARJAN VAN DER GAAG (@AVDGAAG) EMACS INTEGRATION https://github.com/avdgaag/projectile-hanami
41. ARJAN VAN DER GAAG arjanvandergaag.nl • @avdgaag • brightin