[DEX-2143] feat: tooling for proxy mode

.gitlab-ci.yml

@@ -8,7 +8,7 @@ tests:
   image: dreg.sbmt.io/dhub/library/ruby:$RUBY_VERSION
   parallel:
     matrix:
-      - RUBY_VERSION: ['3.0', '3.1', '3.2', '3.3']
+      - RUBY_VERSION: ['3.1', '3.2', '3.3']
   before_script:
     - gem install bundler -v 2.5.7
     - bin/setup

.rubocop.yml

@@ -1,17 +1,54 @@
-inherit_gem:
-  sbmt-dev: config/rubocop.yml
+inherit_from: .rubocop_todo.yml
+
+# We want Exclude directives from different
+# config files to get merged, not overwritten
+inherit_mode:
+  merge:
+    - Exclude
 
 AllCops:
   TargetRubyVersion: 3.3
   TargetRailsVersion: 7.1
-  Exclude:
-    - spec/support/grpc/**/*
+  NewCops: enable
+  SuggestExtensions: false
+
+require:
+  # Performance cops are bundled with Standard
+  - rubocop-performance
+  - rubocop-rails
+  - rubocop-rspec
+  # Standard's config uses custom cops,
+  # so it must be loaded
+  - standard
+
+inherit_gem:
+  standard: config/base.yml
+
+# rubocop-rails
+Rails/SkipsModelValidations:
+  Enabled: false
 
-Style/StringLiterals:
-  EnforcedStyle: single_quotes
+# rubocop-rspec
+RSpec/AnyInstance:
+  Enabled: false
 
-RSpec/FilePath:
+RSpec/MultipleExpectations:
   Enabled: false
 
-RSpec/SpecFilePathFormat:
+RSpec/LetSetup:
   Enabled: false
+
+RSpec/StubbedMock:
+  Enabled: false
+
+RSpec/MessageSpies:
+  Enabled: false
+
+RSpec/NestedGroups:
+  Max: 10
+
+RSpec/ExampleLength:
+  Max: 35
+
+RSpec/MultipleMemoizedHelpers:
+  Max: 15

Appraisals

@@ -3,19 +3,18 @@
 # See compatibility table at https://www.fastruby.io/blog/ruby/rails/versions/compatibility-table.html
 
 versions_map = {
-  '6.1' => %w[3.0],
-  '7.0' => %w[3.1],
-  '7.1' => %w[3.2 3.3]
+  "7.0" => %w[3.1],
+  "7.1" => %w[3.2 3.3]
 }
 
-current_ruby_version = RUBY_VERSION.split('.').first(2).join('.')
+current_ruby_version = RUBY_VERSION.split(".").first(2).join(".")
 
 versions_map.each do |rails_version, ruby_versions|
   ruby_versions.each do |ruby_version|
     next if ruby_version != current_ruby_version
 
     appraise "railties-#{ruby_version}-#{rails_version}" do
-      gem 'railties', "~> #{rails_version}.0"
+      gem "railties", "~> #{rails_version}.0"
     end
   end
 end

Gemfile

@@ -1,10 +1,5 @@
 # frozen_string_literal: true
 
-source 'https://nexus.sbmt.io/repository/rubygems/'
+source "https://nexus.sbmt.io/repository/rubygems/"
 
 gemspec
-
-source 'https://nexus.sbmt.io/repository/ruby-gems-sbermarket/' do
-  gem 'sbmt-app', '~> 1.34'
-  gem 'sbmt-dev', '~> 0.14'
-end

Rakefile

@@ -1,11 +1,11 @@
 # frozen_string_literal: true
 
-require 'bundler/gem_tasks'
-require 'rspec/core/rake_task'
+require "bundler/gem_tasks"
+require "rspec/core/rake_task"
 
 RSpec::Core::RakeTask.new(:spec)
 
-require 'rubocop/rake_task'
+require "rubocop/rake_task"
 
 RuboCop::RakeTask.new
 

config/initializers/strangler.rb

@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+Rails.application.config.after_initialize do
+  Sbmt::Strangler::Builder.call!
+end

config/initializers/yabeda.rb

@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module Sbmt
+  module Strangler
+    module Metrics
+      module Yabeda
+        ::Yabeda.configure do
+          group :sbmt_strangler do
+            counter :params_usage,
+              comment: "Parameters usage counter",
+              tags: %i[params controller action]
+            counter :work_mode,
+              comment: "Strangler mode counter: proxy, parallel, render",
+              tags: %i[mode params controller action]
+          end
+        end
+      end
+    end
+  end
+end

lib/sbmt/strangler.rb

@@ -0,0 +1,64 @@
+# frozen_string_literal: true
+
+require "rails"
+require "dry-monads"
+require "yabeda"
+require "faraday"
+require "faraday/net_http_persistent"
+require "oj"
+
+begin
+  require "sentry-rails"
+rescue LoadError
+  # optional dependency
+end
+
+require_relative "strangler/configurable"
+require_relative "strangler/action"
+require_relative "strangler/controller"
+require_relative "strangler/configuration"
+require_relative "strangler/mixin"
+require_relative "strangler/builder"
+require_relative "strangler/action_invoker"
+require_relative "strangler/const_definer"
+require_relative "strangler/error_tracker"
+require_relative "strangler/logger"
+require_relative "strangler/http"
+
+require_relative "strangler/engine"
+
+module Sbmt
+  module Strangler
+    module_function
+
+    # Public: Configure strangler.
+    #
+    #   Sbmt::Strangler.configure do |config|
+    #     config.controller(...) do |controller|
+    #       controller.action(...) do {...}
+    #     end
+    #   end
+    #
+    # Yields Sbmt::Strangler::Configuration instance.
+    def configure
+      yield configuration if block_given?
+    end
+
+    # Public: Returns Sbmt::Strangler::Configuration instance.
+    def configuration
+      @configuration ||= Configuration.new
+    end
+
+    def action_controller_base_class
+      @action_controller_base_class ||= configuration.action_controller_base_class.constantize
+    end
+
+    def error_tracker
+      @error_tracker ||= configuration.error_tracker.constantize
+    end
+
+    def logger
+      @logger ||= configuration.logger.constantize
+    end
+  end
+end

lib/sbmt/strangler/action.rb

@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+module Sbmt
+  module Strangler
+    class Action
+      extend Sbmt::Strangler::Configurable
+
+      option :params_tracking_allowlist, :headers_allowlist, default_from: :@controller
+
+      attr_accessor :proxy_url, :proxy_http_verb
+      attr_reader :name
+
+      def initialize(name, controller, &)
+        @name = name
+        @controller = controller
+
+        yield(self)
+      end
+    end
+  end
+end

lib/sbmt/strangler/action_invoker.rb

@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+module Sbmt
+  module Strangler
+    class ActionInvoker
+      WORK_MODE = {
+        proxy: "proxy"
+      }.freeze
+
+      def initialize(action, rails_controller)
+        @action = action
+        @rails_controller = rails_controller
+      end
+
+      delegate :http_params, :http_request, :render_proxy_response, :track_params_usage,
+        :track_work_tactic, to: :@rails_controller
+
+      def call
+        track_params_usage
+        track_work_tactic(WORK_MODE[:proxy])
+
+        response = http_request(http_params)
+        render_proxy_response(response)
+      end
+    end
+  end
+end

lib/sbmt/strangler/builder.rb

@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+module Sbmt
+  module Strangler
+    class Builder
+      class << self
+        def call!(configuration = Sbmt::Strangler.configuration)
+          configuration.controllers.each do |controller|
+            unless Object.const_defined?(controller.name)
+              Sbmt::Strangler::ConstDefiner.call!(controller.name, Class.new(Sbmt::Strangler.action_controller_base_class))
+            end
+
+            controller.name.constantize.class_eval do
+              include Sbmt::Strangler::Mixin
+
+              controller.actions.each do |action|
+                define_method(action.name) do
+                  @strangler_action = action
+
+                  Sbmt::Strangler::ActionInvoker.new(action, self).call
+                end
+              end
+            end
+          end
+        end
+      end
+    end
+  end
+end

lib/sbmt/strangler/configurable.rb

@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+
+module Sbmt
+  module Strangler
+    module Configurable
+      def option(*hash)
+        hash in [*attributes, Hash => options]
+
+        attributes.each do |attribute|
+          define_method :"#{attribute}=" do |value|
+            instance_variable_set(:"@#{attribute}", value)
+          end
+
+          define_method attribute.to_s do
+            value = instance_variable_get(:"@#{attribute}")
+            return value if value
+
+            if options[:default_from]
+              value = instance_variable_get(options[:default_from])&.public_send(attribute)
+            end
+
+            value || options[:default]
+          end
+        end
+      end
+    end
+  end
+end

lib/sbmt/strangler/configuration.rb

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+module Sbmt
+  module Strangler
+    class Configuration
+      extend Sbmt::Strangler::Configurable
+
+      option :params_tracking_allowlist, :headers_allowlist, default: []
+      option :action_controller_base_class, default: "ActionController::Base"
+      option :error_tracker, default: "Sbmt::Strangler::ErrorTracker"
+      option :logger, default: "Sbmt::Strangler::Logger"
+
+      attr_reader :controllers, :http
+
+      def initialize(options = {})
+        @controllers = []
+        @http = ActiveSupport::OrderedOptions.new.tap do |c|
+          c.client = "Sbmt::Strangler::Http::Client"
+          c.keepalive_pool_size = Sbmt::Strangler::Http::DEFAULT_KEEPALIVE_POOL_SIZE
+          c.keepalive_idle_timeout = Sbmt::Strangler::Http::DEFAULT_KEEPALIVE_IDLE_TIMEOUT
+          c.timeout = Sbmt::Strangler::Http::DEFAULT_TIMEOUT
+          c.read_timeout = Sbmt::Strangler::Http::DEFAULT_READ_TIMEOUT
+          c.write_timeout = Sbmt::Strangler::Http::DEFAULT_WRITE_TIMEOUT
+          c.open_timeout = Sbmt::Strangler::Http::DEFAULT_OPEN_TIMEOUT
+        end
+      end
+
+      def controller(name, &)
+        @controllers.push(Sbmt::Strangler::Controller.new(name, self, &))
+      end
+    end
+  end
+end

lib/sbmt/strangler/const_definer.rb

@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+module Sbmt
+  module Strangler
+    class ConstDefiner
+      class << self
+        def call!(name, klass)
+          const_names = name.split("::")
+          class_name = const_names.pop
+          module_name = if const_names.any?
+            define_modules(const_names)
+          else
+            Object
+          end
+
+          module_name.const_set(class_name, klass)
+        end
+
+        private
+
+        def define_modules(module_names)
+          module_names.reduce(Object) do |parent_module_name, module_name|
+            define_module(module_name, parent_module_name)
+            "#{parent_module_name}::#{module_name}".constantize
+          end
+        end
+
+        def define_module(module_name, parent_module_name)
+          return if parent_module_name.const_defined?(module_name)
+
+          parent_module_name.const_set(module_name, Module.new)
+        end
+      end
+    end
+  end
+end