[v2] Fat model, skinny controller

app/controllers/todos_controller.rb

@@ -56,10 +56,7 @@ def update
   def complete
     todo = current_user.todos.find(params[:id])
 
-    unless todo.completed?
-      todo.completed_at = Time.current
-      todo.save
-    end
+    todo.complete!
 
     render_json(200, todo: todo_as_json(todo))
   rescue ActiveRecord::RecordNotFound
@@ -69,10 +66,7 @@ def complete
   def activate
     todo = current_user.todos.find(params[:id])
 
-    unless todo.active?
-      todo.completed_at = nil
-      todo.save
-    end
+    todo.activate!
 
     render_json(200, todo: todo_as_json(todo))
   rescue ActiveRecord::RecordNotFound

app/controllers/users/registrations_controller.rb

@@ -2,35 +2,12 @@ class Users::RegistrationsController < ApplicationController
   def create
     user_params = params.require(:user).permit(:name, :password, :password_confirmation)
 
-    password = user_params[:password].to_s.strip
-    password_confirmation = user_params[:password_confirmation].to_s.strip
+    user = User.new(user_params)
 
-    errors = {}
-    errors[:password] = ["can't be blank"] if password.blank?
-    errors[:password_confirmation] = ["can't be blank"] if password_confirmation.blank?
-
-    if errors.present?
-      render_json(422, user: errors)
+    if user.save
+      render_json(201, user: user.as_json(only: [:id, :name, :token]))
     else
-      if password != password_confirmation
-        render_json(422, user: { password_confirmation: ["doesn't match password"] })
-      else
-        password_digest = Digest::SHA256.hexdigest(password)
-
-        user_data = {
-          name: user_params[:name],
-          token: SecureRandom.uuid,
-          password_digest: password_digest,
-        }
-
-        user = User.new(user_data)
-
-        if user.save
-          render_json(201, user: user.as_json(only: [:id, :name, :token]))
-        else
-          render_json(422, user: user.errors.as_json)
-        end
-      end
+      render_json(422, user: user.errors.as_json)
     end
   rescue ActionController::ParameterMissing => e
     render_json(400, error: e.message)

app/models/todo.rb

@@ -31,4 +31,24 @@ def status
 
     'active'
   end
+
+  def complete
+    self.completed_at = Time.current unless completed?
+  end
+
+  def complete!
+    complete
+
+    self.save if completed_at_changed?
+  end
+
+  def activate
+    self.completed_at = nil unless active?
+  end
+
+  def activate!
+    activate
+
+    self.save if completed_at_changed?
+  end
 end

app/models/user.rb

@@ -1,9 +1,45 @@
 class User < ApplicationRecord
   has_many :todos
 
+  attr_accessor :password, :password_confirmation
+
+  before_validation :normalize_and_fill_attributes
+
   with_options presence: true do
     validates :name
     validates :token, length: { is: 36 }, uniqueness: true
-    validates :password_digest, length: { is: 64 }
+    validates :password_digest, length: { is: 64 }, if: ->(user) { user.password_digest.present? }
   end
+
+  validate :password_must_be_filled, on: :create
+  validate :password_must_be_confirmed
+
+  private
+
+    def normalize_and_fill_attributes
+      self.name.try(:squish!)
+      self.password.try(:strip!)
+      self.password_confirmation.try(:strip!)
+
+      self.token = SecureRandom.uuid if token.blank?
+
+      if password_filled? && password == password_confirmation
+        self.password_digest = Digest::SHA256.hexdigest(password)
+      end
+    end
+
+    def password_must_be_filled
+      errors.add(:password, "can't be blank") if password.blank?
+      errors.add(:password_confirmation, "can't be blank") if password_confirmation.blank?
+    end
+
+    def password_must_be_confirmed
+      if password_filled? && password != password_confirmation
+        errors.add(:password_confirmation, "doesn't match password")
+      end
+    end
+
+    def password_filled?
+      password.present? && password_confirmation.present?
+    end
 end

test/controllers/users/registrations_controller/create_test.rb

@@ -13,7 +13,7 @@ class Users::RegistrationsControllerCreateTest < ActionDispatch::IntegrationTest
   end
 
   test "should respond with 400 when the user password params are missing" do
-    post users_registrations_url, params: { user: { password: '' } }
+    post users_registrations_url, params: { user: { name: 'User One' } }
 
     assert_response 422
 
@@ -29,7 +29,7 @@ class Users::RegistrationsControllerCreateTest < ActionDispatch::IntegrationTest
   end
 
   test "should respond with 400 when the user password params are differents" do
-    post users_registrations_url, params: { user: { password: '123', password_confirmation: '321' } }
+    post users_registrations_url, params: { user: { name: 'User Two', password: '123', password_confirmation: '321' } }
 
     assert_response 422