Service Modules

Lightning talk about refactoring Rails services from classes/objects to stateless modules.

Presented at the Ruby on Rails Oceania meetup on 11 July 2017.

Presentation slide deck markdown and speaker notes (useable in Deckset):
https://github.com/paulfioravanti/presentations/tree/master/service_modules

Transcript

1. Service Modules A minor refactoring @paulfioravanti 1
2. @paulfioravanti 2
3. Service Classes @paulfioravanti 3
4. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if user && BCrypt::Password.new(user.password_digest) == params[:password] sign_in user redirect_to dashboard_path else flash[:alert] = "Login failed." render "new" end end end @paulfioravanti 4
5. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if user && BCrypt::Password.new(user.password_digest) == params[:password] sign_in user redirect_to dashboard_path else flash[:alert] = "Login failed." render "new" end end end @paulfioravanti 5
6. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if user && BCrypt::Password.new(user.password_digest) == params[:password] sign_in user redirect_to dashboard_path else flash[:alert] = "Login failed." render "new" end end end @paulfioravanti 6
7. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if user && BCrypt::Password.new(user.password_digest) == params[:password] sign_in user redirect_to dashboard_path else flash[:alert] = "Login failed." render "new" end end end @paulfioravanti 7
8. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if user && BCrypt::Password.new(user.password_digest) == params[:password] sign_in user redirect_to dashboard_path else flash[:alert] = "Login failed." render "new" end end end @paulfioravanti 8
9. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if user && BCrypt::Password.new(user.password_digest) == params[:password] sign_in user redirect_to dashboard_path else flash[:alert] = "Login failed." render "new" end end end @paulfioravanti 9
10. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if user && BCrypt::Password.new(user.password_digest) == params[:password] # ... else # ... end end end @paulfioravanti 10
11. class UserAuthenticator def initialize(user) @user = user end def authenticated?(unencrypted_password) return false unless @user BCrypt::Password.new(@user.password_digest) == unencrypted_password end end @paulfioravanti 11
12. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if UserAuthenticator.new(user).authenticated?(params[:password]) # ... else # ... end end end @paulfioravanti 12
13. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if UserAuthenticator.new(user).authenticated?(params[:password]) sign_in user redirect_to dashboard_path else flash[:alert] = "Login failed." render "new" end end end @paulfioravanti 13
14. ! @paulfioravanti 14
15. BUT @paulfioravanti 15
16. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if UserAuthenticator.new(user).authenticated?(params[:password]) # ... else # ... end end end @paulfioravanti 16
17. authenticator = UserAuthenticator.new(user) authenticator.authenticated? @paulfioravanti 17
18. authenticator = UserAuthenticator.new(user) authenticator.authenticated? authenticator.two_factor_enabled? @paulfioravanti 18
19. authenticator = UserAuthenticator.new(user) authenticator.authenticated? authenticator.two_factor_enabled? authenticator.authenticate_with_facebook @paulfioravanti 19
20. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if UserAuthenticator.new(user).authenticated?(params[:password]) # ... else # ... end end end @paulfioravanti 20
21. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if UserAuthenticator.authenticated?(user, params[:password]) # ... else # ... end end end @paulfioravanti 21
22. class UserAuthenticator def initialize(user) @user = user end def authenticated?(unencrypted_password) return false unless @user BCrypt::Password.new(@user.password_digest) == unencrypted_password end end @paulfioravanti 22
23. class UserAuthenticator def authenticated?(unencrypted_password) return false unless @user BCrypt::Password.new(@user.password_digest) == unencrypted_password end end @paulfioravanti 23
24. class UserAuthenticator def authenticated?(user, unencrypted_password) return false unless @user BCrypt::Password.new(@user.password_digest) == unencrypted_password end end @paulfioravanti 24
25. class UserAuthenticator def authenticated?(user, unencrypted_password) return false unless user BCrypt::Password.new(user.password_digest) == unencrypted_password end end @paulfioravanti 25
26. class UserAuthenticator def self.authenticated?(user, unencrypted_password) return false unless user BCrypt::Password.new(user.password_digest) == unencrypted_password end end @paulfioravanti 26
27. class UserAuthenticator def self.authenticated?(user, unencrypted_password) return false unless user BCrypt::Password.new(user.password_digest) == unencrypted_password end end @paulfioravanti 27
28. ! @paulfioravanti 28
29. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if UserAuthenticator.authenticated?(user, params[:password]) # ... else # ... end end end @paulfioravanti 29
30. BUT @paulfioravanti 30
31. class UserAuthenticator def self.authenticated?(user, unencrypted_password) return false unless user BCrypt::Password.new(user.password_digest) == unencrypted_password end end @paulfioravanti 31
32. class UserAuthenticator def self.authenticated?(user, unencrypted_password) return false unless user BCrypt::Password.new(user.password_digest) == unencrypted_password end end @paulfioravanti 32
33. module UserAuthenticator def self.authenticated?(user, unencrypted_password) return false unless user BCrypt::Password.new(user.password_digest) == unencrypted_password end end @paulfioravanti 33
34. module UserAuthenticator def self.authenticated?(user, unencrypted_password) return false unless user BCrypt::Password.new(user.password_digest) == unencrypted_password end end @paulfioravanti 34
35. module UserAuthenticator module_function def self.authenticated?(user, unencrypted_password) return false unless user BCrypt::Password.new(user.password_digest) == unencrypted_password end end @paulfioravanti 35
36. module UserAuthenticator module_function def authenticated?(user, unencrypted_password) return false unless user BCrypt::Password.new(user.password_digest) == unencrypted_password end end @paulfioravanti 36
37. module UserAuthenticator module_function def authenticated?(user, unencrypted_password) return false unless user BCrypt::Password.new(user.password_digest) == unencrypted_password end end @paulfioravanti 37
38. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if UserAuthenticator.authenticated?(user, params[:password]) sign_in user redirect_to dashboard_path else flash[:alert] = "Login failed." render "new" end end end @paulfioravanti 38
39. class SessionsController < ApplicationController def create user = User.find_by(email: params[:email]) if UserAuthenticator.authenticated?(user, params[:password]) sign_in user redirect_to dashboard_path else flash[:alert] = "Login failed." render "new" end end end @paulfioravanti 39
40. Do you REALLY need that OBJECT? @paulfioravanti 40
41. if not, go module @paulfioravanti 41
42. Thanks! @paulfioravanti @paulfioravanti 42