Mount apt cache of a Vagrant box in the host to spin up the packages installation

gistfile1.md

This is a little trick I use to spin up the packages instalation on Debian/Ubuntu boxes in Vagrant.

I add a simple function that checks if a directory named something similar to ~/.vagrant.d/cache/apt/opscode-ubuntu-12.04/partial (it may have another path in Windows or MacOS) and create the directory if it doesn't already exist.

def local_cache(box_name)
  cache_dir = File.join(File.expand_path(Vagrant::Environment::DEFAULT_HOME),
                        'cache',
                        'apt',
                        box_name)
  partial_dir = File.join(cache_dir, 'partial')
  FileUtils.mkdir_p(partial_dir) unless File.exists? partial_dir
  cache_dir
end

I put this funcion in my Vagrantfile so I can use it like this:

Vagrant::Config.run do |config|
  config.vm.box = "opscode-ubuntu-12.04"
  config.vm.box_url = "https://opscode-vm.s3.amazonaws.com/vagrant/boxes/opscode-ubuntu-12.04.box"
  cache_dir = local_cache(config.vm.box)

  config.vm.share_folder "v-cache",
                         "/var/cache/apt/archives/",
                         cache_dir

end

The result is that the apt cache inside the VM (/var/cache/apt/archives/) is always mounted on the same directory on the host (~/.vagrant.d/cache/apt/opscode-ubuntu-12.04/ in this case) and apt just download the packages the first time or if the package has been updated.

This save me a lot of time while I'm developing or debuging Chef cookbooks. Mostly when my recipes need to install many packages.

This is an excellent tip. Many thanks.

It seems the folder share syntax had changed in the version of Vagrant I downloaded. I needed:

config.vm.synced_folder cache_dir, "/var/cache/apt/archives/"

Other than that it worked great!

Nifty - thanks very much for sharing.

Vagrant::Environment::DEFAULT_HOME no more exists change File.expand_path(Vagrant::Environment::DEFAULT_HOME) to File.dirname(FILE)

Doesn't that make the cache local to the Vagrant project instead of the user's home directory?

@gimier File.dirname(__FILE__) is just the path to your Vagrantfile, which means it will not be in the home directory.
Maybe instead hardcode ~/.vagrant/d instead?

Also everybody should be using https://github.com/fgrehm/vagrant-cachier instead. It's like this gist, but a proper Vagrant plugin... and it's awesome!