Managing Git Submodules in Rails

submodules.rake

# This is used for updating all of our Submodules

# PLUGINS
#
# ==== Description
#
# Define your rails plugins here to be managed by git submodules.
#
#
@plugins =  { 
              # :taggable     => "acts_as_taggable_redux", 
              :asset_packer     => "asset_packager", 
              :exception        => "exception_notification",
              # :openid           => "open_id_authentication",
              :paginate         => "will_paginate",
              :paperclip        => "paperclip",
              :geokit           => "geokit",
              :rspec            => "rspec",
              :rspec_rails      => "rspec_rails",
              :ssl_requirement  => "ssl_requirement",
              :cucumber         => "cucumber",
              :active_merchant  => "active_merchant"
            }

namespace :git do
  
  namespace :submodule do
    desc "When checking out the project, you're gonna need to init the submodules and then update them."
    task :update do
      system('git submodule init')
      system('git submodule update')
    end
    
    desc "Remove a submodule"
    task :remove, :submodule do |task, args|
      git_remove(args.submodule)
    end
      
  end
  
  namespace :update do
    
    # 
    # ==== Description
    #
    # Iterate through the PLUGINS hash so that each plugin
    # can show up as a rake task when doing rake -T
    #
    #
    @plugins.each do |type, file|
      desc "Update #{type.to_s} git submodule"
      task type do
        git_update(file)
      end
    end
    
    
    # Update All Git Submodules
    # 
    # ==== Description
    #
    # This will iterate through our plugins hash and update everything in
    # the hash.
    #
    #
    desc "Update all git submodules"
    task :all do
      @plugins.each do |type, file|
        puts "\nUPDATING & MERGING: #{type.to_s.upcase} Plugin via Git Submodule"
        puts "----------------------------------------------------------------\n"
        git_update(file)
        puts "----------------------------------------------------------------\n"
      end
      puts "\nUPDATING & MERGING: RAILS via Git Submodule"
      puts "----------------------------------------------------------------\n"
      Rake::Task['git:update:rails'].invoke
      puts "----------------------------------------------------------------\n"
    end
    
    
    # Rails
    #
    # ==== Description
    #
    # Update Rails to the latest Edge Version
    #
    #
    desc "Update Rails to the latest Edge Version"
    task :rails do
      git_update
    end

  end
  
end


# Git Update
#
# ==== Description
#
# This accepts a type, which should be a symbol, and then yields itself
# so that the file name of the plugin or rails can be defined.
# It then runs a system command and cd's the specified directory and
# does a git remote update to pull down the latest version of the plugin
# or rails itself and then merges it with the master.
#
#
def git_update(name = nil)
  dir = name.nil? ? "vendor/rails/" : "vendor/plugins/#{name}"
  system("cd #{dir} && git remote update && git merge origin/master")
end


# Git Remove
#
# ==== Description
#
# This will remove a git submodule from the cache.
#
#
def git_remove(submodule)
  system("git rm --cached vendor/plugins/#{submodule}")
end