Small Ruby script that minifies (or un-minifies) JSON files.

minify_json.rb

#!/usr/bin/env ruby

require 'json'

script_name = File.basename(__FILE__)
prettify = false

if ARGV.count < 1
  puts "Minifies JSON files."
  puts ""
  puts "Usage: #{script_name} file.json"
  puts ""
  puts "Options:"
  puts " -p Prettify JSON instead."
  exit
end

ARGV.each do |file|

  if file == '-p' then 
    prettify = true
  else
    data_raw = File.read(file, encoding: 'bom|utf-8')
    old_size = data_raw.length
    new_size = 1
    data = JSON.parse(data_raw)
    File.open(file, 'w') do |f|
      new_json = prettify ? JSON.pretty_generate(data) : JSON.generate(data)
      new_size = new_json.length
      f << new_json
    end
    compression = (new_size.to_f / old_size.to_f) * 100
    puts "  #{file} - ratio: #{'%.2f' % compression}%"
  end

end

puts "Done."