Feature Toggleのために、flipper gemを導入

.traceroute.yml

@@ -35,3 +35,6 @@ ignore_unreachable_actions:
   - .*#recaptcha_enabled?
   - .*#valid_recaptcha?
   - .*#system_test_entrypoint
+  - .*#authorize_feature
+  - .*#authorized_feature?
+  - .*#authorized_feature!

Gemfile

@@ -32,6 +32,7 @@ gem 'diffy'
 gem 'discord-notifier'
 gem 'discordrb', '~> 3.5', require: false
 gem 'doorkeeper'
+gem 'flipper-active_record', '~> 1.3'
 gem 'good_job', '~> 3.14', github: 'komagata/good_job'
 gem 'google-cloud-storage', '~> 1.25', require: false
 gem 'holiday_jp'

Gemfile.lock

@@ -196,6 +196,11 @@ GEM
     ffi (1.17.1)
     ffi (1.17.1-arm64-darwin)
     ffi (1.17.1-x86_64-linux-gnu)
+    flipper (1.3.4)
+      concurrent-ruby (< 2)
+    flipper-active_record (1.3.4)
+      activerecord (>= 4.2, < 9)
+      flipper (~> 1.3.4)
     foreman (0.88.1)
     fugit (1.11.1)
       et-orbi (~> 1, >= 1.2.11)
@@ -676,6 +681,7 @@ DEPENDENCIES
   doorkeeper
   dotenv-rails
   ffi (= 1.17.1)
+  flipper-active_record (~> 1.3)
   foreman
   good_job (~> 3.14)!
   google-cloud-storage (~> 1.25)

app/controllers/application_controller.rb

@@ -3,6 +3,7 @@
 class ApplicationController < ActionController::Base
   include Authentication
   include TestAuthentication if Rails.env.test?
+  include FeatureToggle
   include PolicyHelper
   helper_method :staging?
   protect_from_forgery with: :exception

app/controllers/concerns/feature_toggle.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module FeatureToggle
+  extend ActiveSupport::Concern
+
+  included do
+    helper_method :authorized_feature?
+  end
+
+  def authorized_feature?(feature_key)
+    Flipper[feature_key].enabled?(current_user)
+  end
+
+  def authorized_feature!(feature_key)
+    raise ActionController::RoutingError, 'Feature disabled' unless authorized_feature?(feature_key)
+  end
+
+  def authorize_feature(feature_key, actors)
+    Array(actors).flatten.each do |actor|
+      Flipper.enable_actor(feature_key, actor)
+    end
+  end
+end

config/initializers/flipper.rb

@@ -0,0 +1,45 @@
+Rails.application.configure do
+  ## Memoization ensures that only one adapter call is made per feature per request.
+  ## For more info, see https://www.flippercloud.io/docs/optimization#memoization
+  # config.flipper.memoize = true
+
+  ## Flipper preloads all features before each request, which is recommended if:
+  ##   * you have a limited number of features (< 100?)
+  ##   * most of your requests depend on most of your features
+  ##   * you have limited gate data combined across all features (< 1k enabled gates, like individual actors, across all features)
+  ##
+  ## For more info, see https://www.flippercloud.io/docs/optimization#preloading
+  # config.flipper.preload = true
+
+  ## Warn or raise an error if an unknown feature is checked
+  ## Can be set to `:warn`, `:raise`, or `false`
+  # config.flipper.strict = Rails.env.development? && :warn
+
+  ## Show Flipper checks in logs
+  # config.flipper.log = true
+
+  ## Reconfigure Flipper to use the Memory adapter and disable Cloud in tests
+  # config.flipper.test_help = true
+
+  ## The path that Flipper Cloud will use to sync features
+  # config.flipper.cloud_path = "_flipper"
+
+  ## The instrumenter that Flipper will use. Defaults to ActiveSupport::Notifications.
+  # config.flipper.instrumenter = ActiveSupport::Notifications
+end
+
+Flipper.configure do |config|
+  ## Configure other adapters that you want to use here:
+  ## See http://flippercloud.io/docs/adapters
+  # config.use Flipper::Adapters::ActiveSupportCacheStore, Rails.cache, expires_in: 5.minutes
+end
+
+## Register a group that can be used for enabling features.
+##
+##   Flipper.enable_group :my_feature, :admins
+##
+## See https://www.flippercloud.io/docs/features#enablement-group
+#
+# Flipper.register(:admins) do |actor|
+#  actor.respond_to?(:admin?) && actor.admin?
+# end

db/migrate/20250616101406_create_flipper_tables.rb

@@ -0,0 +1,22 @@
+class CreateFlipperTables < ActiveRecord::Migration[6.1]
+  def up
+    create_table :flipper_features do |t|
+      t.string :key, null: false
+      t.timestamps null: false
+    end
+    add_index :flipper_features, :key, unique: true
+
+    create_table :flipper_gates do |t|
+      t.string :feature_key, null: false
+      t.string :key, null: false
+      t.text :value
+      t.timestamps null: false
+    end
+    add_index :flipper_gates, [:feature_key, :key, :value], unique: true, length: { value: 255 }
+  end
+
+  def down
+    drop_table :flipper_gates
+    drop_table :flipper_features
+  end
+end

db/schema.rb

@@ -328,6 +328,22 @@
     t.index ["question"], name: "index_faqs_on_question", unique: true
   end
 
+  create_table "flipper_features", force: :cascade do |t|
+    t.string "key", null: false
+    t.datetime "created_at", precision: 6, null: false
+    t.datetime "updated_at", precision: 6, null: false
+    t.index ["key"], name: "index_flipper_features_on_key", unique: true
+  end
+
+  create_table "flipper_gates", force: :cascade do |t|
+    t.string "feature_key", null: false
+    t.string "key", null: false
+    t.text "value"
+    t.datetime "created_at", precision: 6, null: false
+    t.datetime "updated_at", precision: 6, null: false
+    t.index ["feature_key", "key", "value"], name: "index_flipper_gates_on_feature_key_and_key_and_value", unique: true
+  end
+
   create_table "followings", force: :cascade do |t|
     t.integer "follower_id"
     t.integer "followed_id"

test/controllers/concerns/feature_toggle_test.rb

@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+class FeatureToggleTest < ActionDispatch::IntegrationTest
+  fixtures :users
+
+  class ExampleController < ApplicationController
+    include FeatureToggle
+
+    attr_accessor :current_user
+  end
+
+  setup do
+    @user = users(:kimura)
+    @controller = ExampleController.new
+    @controller.current_user = @user
+  end
+
+  test 'authorized_feature?' do
+    # All features are disabled by default
+    assert_not @controller.authorized_feature?(:some_feature)
+
+    Flipper.enable(:some_feature, @user)
+    assert @controller.authorized_feature?(:some_feature)
+  end
+
+  test 'authorized_feature!' do
+    # All features are disabled by default
+    error = assert_raises(ActionController::RoutingError) do
+      @controller.authorized_feature!(:some_feature)
+    end
+    assert_equal 'Feature disabled', error.message
+
+    Flipper.enable(:some_feature, @user)
+    assert_nil @controller.authorized_feature!(:some_feature)
+  end
+
+  test 'authorize_feature' do
+    @controller.authorize_feature(:some_feature, [users(:kensyu), User.admins, User.mentor])
+
+    assert_not Flipper[:some_feature].enabled?(@controller.current_user)
+    assert Flipper[:some_feature].enabled?(users(:kensyu))
+    assert Flipper[:some_feature].enabled?(User.admins.to_a.sample)
+    assert Flipper[:some_feature].enabled?(User.mentor.to_a.sample)
+  end
+end