Reverse engineer *.js.map files to *.coffee

jsmap2coffee.rb

#!/usr/bin/env ruby

require "json"
require "fileutils"

# Find all *.js.map files in current directory
files = Dir["./**/*.js.map"]

# Parse out the JSON
mapfiles = files.map { |f| JSON.parse File.read(f) }

# Set where the output should go
export_directory = "./source"

# Nuke the previous output
exec "rm -rf #{export_directory}" if File.directory?(export_directory)

# Iterate over all the sources and resurrect them.
mapfiles.each do |mapfile|
  mapfile["sources"].each_with_index do |source, index|

    # Create a directory for each file.
    outdir = File.dirname("#{export_directory}/#{source}")
    FileUtils.mkdir_p(outdir) unless File.directory?(outdir)

    # Create each file and write out the contents
    outfile = "#{export_directory}/#{source}"
    contents = mapfile["sourcesContent"][index]
    File.open(outfile, "w") { |f| f.write contents }

  end
end