Pretty reformat of JSON file

json_pretty.rb

#!/usr/bin/env ruby

json_file = ARGV[0]
if json_file == nil 
	puts "Usage: #{$PROGRAM_NAME} <json file> [out_file]"
	exit
end

require 'json'

begin
	object = JSON.parse(IO.read json_file)
	out_file = ARGV.fetch(1, json_file)
	IO.write out_file, JSON.pretty_generate(object)
rescue JSON::ParserError => e
	puts "parse failed"
end