Remove unused routes from config/routes.rb

remove_unused_routes

#!/bin/bash
########################################################################
# Add to Gemfile:
#
#   gem 'traceroute', '= 0.2.2'
#
# Then:

bundle install

printf "*** BEFORE ***\n"
time bundle exec rails runner "puts :hello"

bundle exec rake traceroute |
sed -ne '/^Unused/,/^Unreachable/p' |
sed -e '/^U/d' |
bundle exec ruby -e '
  require "active_support/inflector"

  ACTIONS = %w{index new create show edit update destroy}.map(&:to_sym)
  def limit_str(unused_actions)
    only_actions = ACTIONS - unused_actions
    if only_actions.empty?
      ""
    else
      except_actions = ACTIONS & unused_actions
      if except_actions.length < only_actions.length
        ", :except => #{except_actions.inspect}"
      else
        ", :only => #{only_actions.inspect}"
      end
    end
  end

  resources = Hash.new {|hash, key| hash[key] = [] }

  while line = gets
    resource, unused_action = line.chomp("\n").split("#")
    resources[resource.strip] << unused_action.to_sym
  end

  File.open("config/routes.rb") do |io|
    io.each_line do |line|
      case line
      when /resource :(\w+)(?:, :controller => '\''(.*?)'\'')?/
        if unused_actions = resources.delete($2 || $1.pluralize)
          line.sub!(/resource :#{$1}/, "resource :#{$1}#{limit_str(unused_actions)}")
        end
      when /resources :(\w+)(?:, :controller => '\''(.*?)'\'')?/
        if unused_actions = resources.delete($2 || $1)
          line.sub!(/resources :#{$1}/, "resources :#{$1}#{limit_str(unused_actions)}")
        end
      end
      puts line
    end
  end

  $stderr.puts "Leftover:"
  $stderr.puts resources.inspect
' > new_routes.rb

mv new_routes.rb config/routes.rb

printf "*** AFTER ***\n"
time bundle exec rails runner "puts :hello"

Be advised this script is brittle. At the end it prints out any routes that were not updated. In our case that happened because the non-updated route was not written with one of these patterns of symbols and strings.

  resource :thing
  resources :things
  resource :thing, :controller => 'controller'
  resuorces :things, :controller => 'controller'