gistfile1.rb

# In attribute file:
my_gem_packages = [
  "nokigiri", # Only a gem name, without a version requirement or other options"
  ["bundler", "=1.0.0"], # A gem with a version requirement
  ["rails", "~>2.3.9", "--no-ri --no-rdoc --source http://rubygems.org"], # A gem with a version requirement and options"
  ["json", nil, "--source http://rubygems.org"] # Gem with options but no version requirement
]

# In recipe:

my_gem_packages.each do |name, ver, opts|
  gem_package(name) do
    action :install
    version ver if ver
    options opts if opts
  end
end