Parses production logs and checks which routes are used out of all the routes that are defined.

routes_check.rake

  desc 'Show basic controller usage stats'
  task :controllers => :environment do
    logfiles = Dir['log/%s.log*' % Rails.env].sort
    logs_gz, logs_txt = logfiles.partition{|f| Pathname.new(f).extname == '.gz' }
    results = `ag Started -A 1 #{logs_txt.join(' ')}`
    unless logs_gz.empty?
      results << `zcat #{logs_gz.join(' ')} |ag Started -A 1`
    end
    Event = Struct.new(:http_method, :uri_path, :client_ip, :requested_at_str, :controller_name, :controller_action, :format) do
      def requested_at
        Chronic.parse(requested_at_str)
      end
      def action_fmt
        [controller_name, controller_action].join('#')
      end
    end
    events_raw = results.lines.each_cons(2)
    events = events_raw.map{|lines|
      next unless lines.first =~ /Started/ && lines.last =~ /Processing/
      # Started GET "/auth/signin" for 1.2.3.4 at 2018-07-30 09:22:15 -0400 ()
      # Processing by UserSessionController#new as HTML ()
      started_m = /Started (?<http_method>\w+) "(?<uri_path>[^ ]*)" for (?<client_ip>\d+\.\d+\.\d+\.\d+) at (?<requested_at_str>[^ ]+ [^ ]+ [^ ]+)(?: .*)?/.match(lines.first)&.named_captures
      processing_m = /Processing by (?<controller_name>[^ ]+)#(?<controller_action>\w+) as (?<format>[^ ]+)(?: .*)?/.match(lines.last)&.named_captures
      next if started_m.nil?
      next if processing_m.nil?
      e = Event.new(*started_m.merge(processing_m).values)
      e
    }.compact

    logged_controller_action_events = events.group_by(&:action_fmt)

    defined_controller_actions = []
    Zeitwerk::Loader.eager_load_all
    ApplicationController.descendants.each do |clazz|
      methods = clazz.instance_methods - ApplicationController.instance_methods
      methods.each do |method|
        defined_controller_actions << OpenStruct.new(controller_name: clazz.name, controller_action: method, action_fmt: "#{clazz.name}##{method}")
      end
    end

    all_controller_actions = (logged_controller_action_events.keys + defined_controller_actions.map(&:action_fmt)).compact.uniq.sort

    table = Terminal::Table.new headings: %w[Action Requests Earliest Latest Latest_rel]
    all_controller_actions.each do |controller_action|
      events = logged_controller_action_events[controller_action]
      if events.present?
        dates = events.map(&:requested_at)
        min_date = dates.min.to_date
        max_date = dates.max
        #puts "%d\t%s (earliest: %s, latest: %s (%s)" % [events.count, controller_action, min_date, max_date, time_ago_in_words(max_date)]
        table << [controller_action, events.count, min_date, max_date, time_ago_in_words(max_date)]
      else
        table << [controller_action, Rainbow('No Log').gray, nil, nil, nil]
      end
    end
    puts table
  end