Brewstrap: Taps the taps, installs the formulae & casks

brewstrap.rb

#!/usr/bin/env ruby
require 'yaml'

CONFIG_FILE_NAME          = 'brewstrap.yml'
COMMAND_INSTALL_CASK      = 'brew install caskroom/cask/brew-cask'
COMMAND_BREW_UPDATE       = 'brew update'
COMMAND_FORMULA_INSTALL   = 'brew install'
COMMAND_BREW_TAP          = 'brew tap'
COMMAND_BREW_CASK_INSTALL = 'brew cask install --appdir=/Applications'

def perform_command(command)
  puts "Performing command: #{command}"
  IO.popen(command) do |io|
    while (line = io.gets) do
      puts line
    end
  end
end

def perform_command_per_item(items, command)
  items.each{ |item| perform_command("#{command} #{item}") }
end

def check_for_homebrew!
  puts "Checking for homebrew\n"
  if system('brew --version')
    puts "Homebrew installed...\n"
  else
    puts 'Please install Homebrew! Run the following command:'
    puts 'ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"'
    abort "Exiting..."
  end
  puts
end

def install_cask_if_needed
  puts "Checking for brew cask\n"
  if system('brew cask --version')
    puts "Brew cask installed...\n"
  else
    puts "Installing brew cask...\n"
    perform_command(COMMAND_INSTALL_CASK)
  end
  puts
end

def load_config
  abort "Cannot find #{CONFIG_FILE_NAME}" unless File.exist?(CONFIG_FILE_NAME)
  YAML.load_file(CONFIG_FILE_NAME)
end

check_for_homebrew!
install_cask_if_needed
perform_command(COMMAND_BREW_UPDATE)

config    = load_config
taps      = config.fetch('taps', [])
formulae  = config.fetch('formulae', [])
casks     = config.fetch('casks', [])

puts "\nInstalling taps...\n"
perform_command_per_item(taps, COMMAND_BREW_TAP)

puts "\nInstalling formulae...\n"
perform_command_per_item(formulae, COMMAND_FORMULA_INSTALL)

puts "\nInstalling casks...\n"
perform_command_per_item(casks, COMMAND_BREW_CASK_INSTALL)

brewstrap.yml

taps:
  - git-duet/tap
formulae:
  - ssh-copy-id
  - tmux
  - tree
  - wget
  - rbenv
  - rbenv-gem-rehash
  - git-duet
casks:
  - iterm2
  - appcode
  - atom
  - textmate
  - sublime-text
  - flycut
  - shiftit
  - bettertouchtool
  - google-chrome
  - firefox
  - google-hangouts
  - screenhero
  - xquartz