easy-going-rails/lib/semantic/dev_loader.rb

module Semantic
  # use the Zeitwerk autoloader to reattach_appender for development autoreloading feature
  class DevLoader
    def initialize
      Rails.autoloaders.main.on_load('ApplicationController') do
        append_ansi_formatter
        append_subscriber_once
      end
      append_ansi_formatter
    end

    private

    def append_ansi_formatter
      SemanticLogger.clear_appenders!
      formatter = Semantic::AnsiFormatter.new
      SemanticLogger.add_appender(io: $stdout,
                                  formatter:,
                                  filter: ->(log) { !formatter.reject(log) })
    end

    def append_subscriber_once
      return unless @previous_subscribe.nil?

      @previous_subscribe = ActiveSupport::Notifications.subscribe 'start_processing.action_controller' do |event|
        Semantic::LogSubscriber.new.start_processing(event)
      end
    end
  end
end