gistfile1.txt

bash 'install science app' do
  installed_version_file = "#{app[:base_dir]}/.#{app[:version]}-installed"
  cwd Chef::Config[:file_cache_path]
  code <<-BASH
    tar zxf #{app[:tarball]} -C #{app[:deploy_to]}
    cp #{app[:tarball]} #{app[:deploy_to]} 
    touch #{installed_version_file}   
  BASH
  not_if { ::File.exist?(installed_version_file) }
end

ruby_block "get digest" do
  block do
  requirements = File.open(app[:requirements_file],"rb")
  digest = Digest::MD5.hexdigest(requirements.read)
  virtual_env_tarball = "virtual_env-#{digest}.tgz"
  end
  action :create
end

remote_file "#{Chef::Config[:file_cache_path]}/#{virtual_env_tarball}" do
  source "#{node[:virtual_env][:base_url]}/#{digest}/#{virtual_env_tarball}"
  mode 0644
  action :create_if_missing
end