An automated Ruby script for grabbing the latest Mac Chromium build

chromium_updater.rb

#!/usr/bin/env ruby

# A simple Ruby script to update Chromium from dev build.
# Currently only works on Mac and Win32.
# If you want progress bar, sudo gem install ruby-progressbar       
# Read more about progress bar here: http://github.com/nex3/ruby-progressbar/tree/master 
# Usage:
#   ruby chromium_updater.rb 

require 'fileutils'
require 'open-uri'
require 'tmpdir'

module ChromiumBuild
  BUILD_SNAPSHOT_URL = 'http://commondatastorage.googleapis.com/chromium-browser-snapshots'
  
  class Updater
    attr_accessor :install_path, :build_dir, :platform

    def initialize( install_path, build_dir, platform )
      self.install_path = install_path
      self.build_dir = build_dir
      self.platform = platform.to_s
      @latest_revision_uri = URI.parse("#{BUILD_SNAPSHOT_URL}/#{@platform.capitalize}/LAST_CHANGE")
    end
    
    def update
      build
      unpack
      cleanup
    end
    
    def unpack
      ## platform specific
    end
    
    def cleanup
      ## platform specific
    end
    
    def build
      @build ||= get_build
    end
    
    begin
      # Use http://github.com/nex3/ruby-progressbar/tree/master 
      # sudo gem install nex3-ruby-progressbar
      require 'rubygems'
      require 'progressbar'
      def get_build
        @build = File.open(File.join(build_dir, build_filename), 'wb')
        pbar = nil
        open(latest_build_uri,
            :content_length_proc => lambda {|t|
              if t && 0 < t
                pbar = ProgressBar.new("Downloading #{latest_build_uri}", t)
                pbar.file_transfer_mode
              end
            },
            :progress_proc => lambda {|s|
              pbar.set s if pbar
            }) {|f| @build.write(f.read) }
      ensure
        @build.close
        pbar && pbar.finish
        return @build        
      end
    # start download w/o using progress bar
    rescue LoadError => e
      def get_build
        @build = File.open(File.join(build_dir, build_filename), 'w')
        puts latest_build_uri
        @build.write(latest_build_uri.read)
      ensure
        @build.close
        return @build
      end
    end
    
    def latest_revision
      @latest_revision ||= get_latest_revision
    end
    
    protected      
      def latest_build_uri
        URI.parse "#{BUILD_SNAPSHOT_URL}/#{@platform.capitalize}/#{latest_revision}/#{build_filename}"
      end
      
      def get_latest_revision
        @latest_revision = @latest_revision_uri.read
      end
      
      def build_filename
        "#{build_basename}.zip"
      end

      def build_basename
        "chrome-#{@platform}"
      end
  end
  
  class Win32Updater < Updater
    def initialize( install_path="C:/Program Files/Google/Chromium", build_dir=Dir.tmpdir )
        super(install_path, build_dir, 'win')
    end
    
    def unpack
        begin
            puts %x["C:/Program Files/7-Zip/7z.exe" e #{build.path} -o#{File.join(build_dir, build_basename)} -y]
        rescue
            puts 'Error: Please install 7-zip under C:\Program Files\7-Zip\\'
            exit
        end
        begin
            FileUtils.cp_r  Dir.glob(extracted_app_path + "/*"), install_path, :verbose => true, :preserve => true
        rescue
            puts "Error: Please close Chromium before updating"
            exit
        end
    end
    
    def build_basename
        "chrome-#{@platform}32"
    end
    
    def cleanup
      FileUtils.rm_rf Dir.glob(File.join(build_dir, "#{build_basename}*")), :verbose => true
    end
    
    private 
        def extracted_app_path
            File.join build_dir, build_basename
        end
  end
  
  class MacUpdater < Updater
    def initialize( install_path='/Applications/Chromium.app', build_dir=Dir.tmpdir )
      super(install_path, build_dir, 'mac')
    end
    
    def unpack
        `unzip #{build.path} -d #{build_dir}`
        FileUtils.rm_rf install_path
        FileUtils.cp_r  extracted_app_path, install_path, :verbose => true, :preserve => true
    end
    
    def cleanup
      FileUtils.rm_rf Dir.glob(File.join(build_dir, "#{build_basename}*")), :verbose => true
    end
    
    private 
      def extracted_app_path
        File.join build_dir, build_basename, 'Chromium.app'
      end
  end
  
end

module Platform
    def self.is_mac?
        RUBY_PLATFORM.downcase.include?("darwin")
    end

    def self.is_windows?
        RUBY_PLATFORM.downcase.include?("w32")
     end

    def self.is_linux?
        RUBY_PLATFORM.downcase.include?("linux")
    end
end

if __FILE__ == $0
  if Platform.is_mac?
    updater = ChromiumBuild::MacUpdater.new
  elsif Platform.is_windows?
    updater = ChromiumBuild::Win32Updater.new
  end
  
  unless updater
    puts "unsupported platform #{RUBY_PLATFORM}"
    exit
  end
 
  puts "Downloading rev ##{updater.latest_revision}..."
  updater.get_build
  puts "Unpacking..."
  updater.unpack
  puts "Cleaning up..."
  updater.cleanup
  puts "All done!"
end

• updated with new paths of chromium builds
• MacUpdater: added the option "preserve" to cp_r in order to make Chromium.app executable

• using the new google api for downloads (commondatastorage.googleapis.com/chromium-browser-snapshots)