generate a (partial) rubygems mirror

rubygem_mirror.sh

## Purpose: create a partial Rubygems mirror on Debian (7 AKA wheezy)
## Design goal: no system wide gems other than Debian packages

# make sure bundler, ruby-builder (required for generate_index) + rubygems-integration (required for gem<->builder integration) are available:
% sudo apt-get install ruby-bundler ruby-builder rubygems-integration

# We use gem-mirror (http://rubygems.org/gems/gem-mirror / https://github.com/YorickPeterse/gem-mirror), so
# install gem-mirror gem itself (requires ruby >=1.9) in local directory for execution via bundler:
% cat Gemfile
source 'https://rubygems.org/'
gem "gem-mirror"
% ruby1.9.1 -S bundle install --path=vendor

# Initialize mirror (creates template config.rb file):
% ruby1.9.1 -S bundle exec gem-mirror init

# Adjust gem-mirror configuration:
% cat config.rb
# This is the main configuration file for your RubyGems mirror. Here you can
# change settings such as the location to store Gem files in and what sources
# and Gems you'd like to mirror.
GemMirror.configuration.configure do
  # The directory to store indexing information as well as the Gem files in.
  destination File.expand_path('../public', __FILE__)

  # Directory to use for storing SHA512 checksums of each Gem.
  checksums File.expand_path('../public/checksums', __FILE__)

  # When set to `true` development dependencies of Gems will also be mirrored.
  development false

  # If you're mirroring a lot of Gems you'll probably want to switch the
  # logging level to Logger::ERROR or Logger::INFO to reduce the amount of
  # noise.
  logger.level = Logger::DEBUG

  # A source is a remote location that you want to mirror. The first parameter
  # of this method is the human readable name, the second one the URL. The
  # supplied block is used to determine what Gems (and versions) to mirror.
  source 'rubygems', 'https://rubygems.org' do
    gem "selenium-webdriver"
    gem "rspec"
    gem "syntax"
    gem 'rubyzip'
    gem 'childprocess'
    gem 'diff-lcs'
    gem 'websocket'
  end
end

# Update mirror (retrieving gems):
% ruby1.9.1 -S bundle exec gem-mirror update

# Checksums:
% ruby1.9.1 -S bundle exec gem-mirror checksums

# (NOTE: "gem-mirror index" as well as "ruby1.9.1 -S bundle exec gem1.9.1 generate_index --directory public/"
# are broken when executed inside the bundler directory, they announce the bundler gems from the vendor
# directory instead, see https://github.com/YorickPeterse/gem-mirror/issues/9 for details.)
# Generate index:
% gem1.9.1 generate_index --no-legacy --directory public

# Now you can announce the public directory through your webserver, like
% sudo ln -s /srv/mirror/rubygems/public/ /var/www/rubygems