【serverside_challenge_2 : sasaki】プランごとの電気料金を返すAPIの実装

serverside_challenge_2/challenge/.rspec

@@ -0,0 +1 @@
+--require spec_helper

serverside_challenge_2/challenge/.rubocop.yml

@@ -0,0 +1,27 @@
+inherit_from: .rubocop_todo.yml
+
+require: rubocop-rails # 必須
+
+AllCops:
+  # 除外するディレクトリ（自動生成されるファイル）
+  Exclude:
+    - 'db/**/*'
+    - 'config/**/*'
+    - 'bin/**/*'
+    - 'test/**/*'
+    - 'spec/rails_helper.rb'
+    - 'spec/spec_helper.rb'
+    - 'Gemfile'
+    - 'Rakefile'
+  NewCops: enable
+
+Style/Documentation:
+  Enabled: false
+
+Lint/EmptyBlock:
+  Exclude:
+    - 'spec/factories/**/*'
+
+Metrics/BlockLength:
+  Exclude:
+    - 'spec/**/*'

serverside_challenge_2/challenge/.rubocop_todo.yml

@@ -0,0 +1,26 @@
+# This configuration was generated by
+# `rubocop --auto-gen-config --auto-gen-only-exclude --exclude-limit 999999`
+# on 2024-05-17 06:56:05 UTC using RuboCop version 1.63.5.
+# The point is for the user to remove these configuration records
+# one by one as the offenses are removed from the code base.
+# Note that changes in the inspected code, or installation of new
+# versions of RuboCop, may require this file to be generated again.
+
+# Offense count: 4
+# Configuration parameters: Include.
+# Include: app/models/**/*.rb
+Rails/UniqueValidationWithoutIndex:
+  Exclude:
+    - 'app/models/basic_rate.rb'
+    - 'app/models/electricity_plan.rb'
+    - 'app/models/provider.rb'
+    - 'app/models/usage_rate.rb'
+
+# Offense count: 3
+# This cop supports safe autocorrection (--autocorrect).
+# Configuration parameters: EnforcedStyle, ConsistentQuotesInMultiline.
+# SupportedStyles: single_quotes, double_quotes
+Style/StringLiterals:
+  Exclude:
+    # - 'app/mailers/application_mailer.rb'
+    # - 'config.ru'

serverside_challenge_2/challenge/Gemfile

@@ -34,15 +34,23 @@ gem "bootsnap", require: false
 # gem "image_processing", "~> 1.2"
 
 # Use Rack CORS for handling Cross-Origin Resource Sharing (CORS), making cross-origin AJAX possible
-# gem "rack-cors"
+gem 'rack-cors'
 
 group :development, :test do
   # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem
   gem "debug", platforms: %i[ mri mingw x64_mingw ]
+  gem 'rspec-rails'
+  gem 'factory_bot_rails'
 end
 
 group :development do
   # Speed up commands on slow machines / big apps [https://github.com/rails/spring]
   # gem "spring"
+  gem 'rubocop', require: false
+  gem 'rubocop-performance', require: false
+  gem 'rubocop-rails', require: false
 end
 
+group :test do
+  gem 'shoulda-matchers'
+end

serverside_challenge_2/challenge/Gemfile.lock

@@ -66,6 +66,7 @@ GEM
       i18n (>= 1.6, < 2)
       minitest (>= 5.1)
       tzinfo (~> 2.0)
+    ast (2.4.2)
     bootsnap (1.18.3)
       msgpack (~> 1.2)
     builder (3.2.4)
@@ -75,7 +76,13 @@ GEM
     debug (1.9.1)
       irb (~> 1.10)
       reline (>= 0.3.8)
+    diff-lcs (1.5.1)
     erubi (1.12.0)
+    factory_bot (6.4.6)
+      activesupport (>= 5.0.0)
+    factory_bot_rails (6.4.3)
+      factory_bot (~> 6.4)
+      railties (>= 5.0.0)
     globalid (1.2.1)
       activesupport (>= 6.1)
     i18n (1.14.1)
@@ -84,6 +91,8 @@ GEM
     irb (1.11.2)
       rdoc
       reline (>= 0.4.2)
+    json (2.7.2)
+    language_server-protocol (3.17.0.3)
     loofah (2.22.0)
       crass (~> 1.0.2)
       nokogiri (>= 1.12.0)
@@ -111,13 +120,19 @@ GEM
       racc (~> 1.4)
     nokogiri (1.16.2-x86_64-linux)
       racc (~> 1.4)
+    parallel (1.24.0)
+    parser (3.3.1.0)
+      ast (~> 2.4.1)
+      racc
     pg (1.5.4)
     psych (5.1.2)
       stringio
     puma (5.6.8)
       nio4r (~> 2.0)
     racc (1.7.3)
     rack (2.2.8)
+    rack-cors (2.0.2)
+      rack (>= 2.0.0)
     rack-test (2.1.0)
       rack (>= 1.3)
     rails (7.0.8)
@@ -148,16 +163,61 @@ GEM
       rake (>= 12.2)
       thor (~> 1.0)
       zeitwerk (~> 2.5)
+    rainbow (3.1.1)
     rake (13.1.0)
     rdoc (6.6.2)
       psych (>= 4.0.0)
+    regexp_parser (2.9.1)
     reline (0.4.2)
       io-console (~> 0.5)
+    rexml (3.2.6)
+    rspec-core (3.13.0)
+      rspec-support (~> 3.13.0)
+    rspec-expectations (3.13.0)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.13.0)
+    rspec-mocks (3.13.1)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.13.0)
+    rspec-rails (6.1.2)
+      actionpack (>= 6.1)
+      activesupport (>= 6.1)
+      railties (>= 6.1)
+      rspec-core (~> 3.13)
+      rspec-expectations (~> 3.13)
+      rspec-mocks (~> 3.13)
+      rspec-support (~> 3.13)
+    rspec-support (3.13.1)
+    rubocop (1.63.5)
+      json (~> 2.3)
+      language_server-protocol (>= 3.17.0)
+      parallel (~> 1.10)
+      parser (>= 3.3.0.2)
+      rainbow (>= 2.2.2, < 4.0)
+      regexp_parser (>= 1.8, < 3.0)
+      rexml (>= 3.2.5, < 4.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (>= 2.4.0, < 3.0)
+    rubocop-ast (1.31.3)
+      parser (>= 3.3.1.0)
+    rubocop-performance (1.21.0)
+      rubocop (>= 1.48.1, < 2.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
+    rubocop-rails (2.24.1)
+      activesupport (>= 4.2.0)
+      rack (>= 1.1)
+      rubocop (>= 1.33.0, < 2.0)
+      rubocop-ast (>= 1.31.1, < 2.0)
+    ruby-progressbar (1.13.0)
+    shoulda-matchers (6.2.0)
+      activesupport (>= 5.2.0)
     stringio (3.1.0)
     thor (1.3.0)
     timeout (0.4.1)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
+    unicode-display_width (2.5.0)
     websocket-driver (0.7.6)
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.5)
@@ -170,9 +230,16 @@ PLATFORMS
 DEPENDENCIES
   bootsnap
   debug
+  factory_bot_rails
   pg (~> 1.1)
   puma (~> 5.0)
+  rack-cors
   rails (~> 7.0.8)
+  rspec-rails
+  rubocop
+  rubocop-performance
+  rubocop-rails
+  shoulda-matchers
   tzinfo-data
 
 RUBY VERSION

serverside_challenge_2/challenge/app/channels/application_cable/channel.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ApplicationCable
   class Channel < ActionCable::Channel::Base
   end

serverside_challenge_2/challenge/app/channels/application_cable/connection.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ApplicationCable
   class Connection < ActionCable::Connection::Base
   end

serverside_challenge_2/challenge/app/controllers/api/electricity_rate_simulations_controller.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Api
+  class ElectricityRateSimulationsController < ApplicationController
+    def index
+      params = electricity_rate_simulation_params
+      electricity_rate_simulation = ElectricityRateSimulation.new(params['amperage'], params['usage_kwh'])
+
+      raise ActiveModel::ValidationError, electricity_rate_simulation if electricity_rate_simulation.invalid?
+
+      simulation_result = electricity_rate_simulation.execute
+
+      render json: simulation_result
+    end
+
+    private
+
+    def electricity_rate_simulation_params
+      params.require(%i[amperage usage_kwh])
+      params.permit(:amperage, :usage_kwh)
+    end
+  end
+end

serverside_challenge_2/challenge/app/controllers/application_controller.rb

@@ -1,2 +1,16 @@
+# frozen_string_literal: true
+
 class ApplicationController < ActionController::API
+  rescue_from ActionController::ParameterMissing, with: :parameter_missing
+  rescue_from ActiveModel::ValidationError, with: :validation_error
+
+  private
+
+  def parameter_missing(error)
+    render json: { error: error.message }, status: :bad_request
+  end
+
+  def validation_error(error)
+    render json: { error: error.model.errors.full_messages }, status: :unprocessable_entity
+  end
 end

serverside_challenge_2/challenge/app/jobs/application_job.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ApplicationJob < ActiveJob::Base
   # Automatically retry jobs that encountered a deadlock
   # retry_on ActiveRecord::Deadlocked

serverside_challenge_2/challenge/app/mailers/application_mailer.rb

@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 class ApplicationMailer < ActionMailer::Base
-  default from: "[email protected]"
-  layout "mailer"
+  default from: '[email protected]'
+  layout 'mailer'
 end

serverside_challenge_2/challenge/app/models/application_record.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ApplicationRecord < ActiveRecord::Base
   primary_abstract_class
 end

serverside_challenge_2/challenge/app/models/basic_rate.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+class BasicRate < ApplicationRecord
+  belongs_to :electricity_plan
+
+  validates :amperage, presence: true, uniqueness: { scope: :electricity_plan_id }
+  validates :rate, presence: true
+  validates :rate, numericality: { greater_than_or_equal_to: 0 }
+
+  scope :find_rate_by_amperage, ->(amperage) { find_by(amperage:).rate }
+end

serverside_challenge_2/challenge/app/models/electricity_plan.rb

@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+class ElectricityPlan < ApplicationRecord
+  belongs_to :provider
+  has_many :basic_rates, dependent: :destroy
+  has_many :usage_rates, dependent: :destroy
+
+  validates :name, presence: true
+  validates :name, uniqueness: { scope: :provider_id }
+
+  def calculate_total_amount(amperage, usage_kwh)
+    total_price = BigDecimal(0)
+
+    # 基本料金
+    total_price += basic_rates.find_rate_by_amperage(amperage)
+    # 従量料金
+    total_price += UsageRate.calculate_total(usage_kwh, usage_rates)
+
+    total_price.floor
+  end
+end

serverside_challenge_2/challenge/app/models/electricity_rate_simulation.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+class ElectricityRateSimulation
+  include ActiveModel::Model
+  include ActiveModel::Attributes
+  include ActiveRecord::AttributeMethods::BeforeTypeCast
+
+  attribute :amperage, :integer
+  attribute :usage_kwh, :integer
+
+  validates :amperage, presence: true, numericality: { only_integer: true }
+  validates :amperage, inclusion: { in: [10, 15, 20, 30, 40, 50, 60] }
+  validates :usage_kwh, presence: true, numericality: { only_integer: true, greater_than_or_equal_to: 0 }
+
+  def initialize(amperage, usage_kwh)
+    super(amperage:, usage_kwh:)
+  end
+
+  def execute
+    ElectricityPlan.preload(:provider, :basic_rates, :usage_rates).map do |plan|
+      calculate_rate_plan(plan)
+    end
+  end
+
+  def calculate_rate_plan(plan)
+    return SimulationResult.not_found_basic_amperage(plan) if plan.basic_rates.find_by(amperage:).blank?
+
+    total_amount = plan.calculate_total_amount(amperage, usage_kwh)
+
+    SimulationResult.new(plan, total_amount)
+  end
+end

serverside_challenge_2/challenge/app/models/provider.rb

@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+class Provider < ApplicationRecord
+  has_many :electricity_plans, dependent: :destroy
+
+  validates :name, presence: true
+  validates :name, uniqueness: true
+end

serverside_challenge_2/challenge/app/models/simulation_result.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+class SimulationResult
+  attr_reader :provider_name, :plan_name, :total_amount, :error_message
+
+  def initialize(plan, total_amount, error_message = nil)
+    @provider_name = plan.provider&.name
+    @plan_name = plan.name
+    @total_amount = total_amount
+    @error_message = error_message
+  end
+
+  def self.not_found_basic_amperage(plan)
+    new(plan, nil, 'アンペア数に対応する基本料金が見つからないため料金を計算できません')
+  end
+end