Vagrant is a command line tool for managing virtual machines aimed at virtualising your development environment. It is essentially a wrapper around Oracle's VirtualBox but a very good one.

Getting started is really easy, there is a good quick start on the Vagrant website, or you can try my version to get a development environment I've been using - which is a basic box with some Python tools and postgres. Vagrant projects are initialised for a directory and simply contains a file called Vagrantfile (and an automatically generated .vagrant file). Generally speaking I would then do this once in each project root allowing the vagrant file to be version controlled and configured for an individual project. Then each developer can create a virtual machine from the same config and this keeps everybody on the same page.

sudo gem update --system
gem install vagrant
cd /path/to/project
vagrant init

You may not need the first step there, but I did on my mac. There is a detailed setup guide for different platforms here. So if you have any problems make sure you read that first.

In your current directory you should now have a file named Vagrantfile. This is a simple Ruby based configuration file. The Vagrantfile is well documented so we'll skip past that bit. Instead, copy the following into your vagrant file.

Vagrant::Config.run do |config|

  config.vm.box = "lucid32"
  config.vm.box_url = "http://files.vagrantup.com/lucid32.box"

  config.vm.forward_port("web", 8000, 8000)
  config.vm.network("33.33.00.10")

  config.vm.provision :chef_solo do |chef|

    chef.recipe_url = "http://cloud.github.com/downloads/d0ugal/chef_recipes/cookbooks.tar.gz"
    chef.cookbooks_path = [:vm, "cookbooks"]

    chef.add_recipe "main"
    chef.add_recipe "python"
    chef.add_recipe "postgres"

    chef.json.merge!({

      :project_name => "project_name",

      :system_packages => [],
      :python_global_packages => [],
      :python_packages => [],

    })

  end

end

After copying in, look for project_name and change that to something on your liking or you can just leave it for now.

If you have already been using vagrant, you will likely have the lucid box already. The vagrant quick start tips download it and call it 'base' since this is a common name I have changed it to something more explicit and safe. However, to avoid re-downloading you may want to change lucid32 to base in your config file.

What does this do? It setups up a new Ubuntu Lucid machine and runs some chef recipies against that are downloading from my chef github repository. The base machine that its built on is downloaded from the url in the config this is provided by the Vagrant team (I've not had a chance to make my own boxes yet).

The Chef cookbook then installs some system wide packages, creates a virtual environment, installs postgres and creates a database. These are not deploy ready scripts but rather more hacky scripts to quickly bootstrap a development env.

After saving, you can now do vagrant up this will take a while as it needs to download the ubuntu box to create the VM from. The time delay is mostly due to downloading of the box and also various packages like postgres so be warned if you have a slow or limited connection, this is likely to sum up to around 800mb or so.

After its finished, you should be able to do this.

vagrant ssh
workon project_name
ls -la

You will then be running from the virtual machine, but be in an activated Python virtual environment and in a directory that is mapped to the host machine. Thus the result of that should show the files for the directory that you started in. In my case I generally then need to do pip install -r requirements.txt and after that I can run the project - be it a Django website, or something different.

After this you can pretty much carry on as normal. There are a few things to note that may effect you. Any tools that rely on accessing the Python interpreter will not work as its not on a remote machine, I don't have a need for this so I've not worked out a solution. I simply use the python debugger directly in the ssh session. Editors like pyDev will likely loose some functionality here but there may be a work around...

When using Django's runserver, you need to specify an IP address. I've created a alias to make this easier. This assumes you are still connected to the virtual machine but if not, cd into the project directory and run vagrant ssh. How awesome is it to not need to remember IP's or logins?

djr
# is the same as
python manage.py runserver 0.0.0.0:8000

These shortcuts are best left for another post perhaps, but some more can be seen in my dotfiles repository.

To access the site itself, you'll then need to go to the IP address specified in the config file. In this case the full path will be http://33.33.00.10:8000 or since we have set the port forwarding in the config above you should be able to go to localhost:8000.

I'm still working out my complete workflow for vagrant but I'm using this machine as a base point for much of my work and creating a new machine for each project. The best thing so far for me is a recorded development environment that I can use to create a VM now or in 6 months when revisiting an older project. My main problem at the moment is the effort required to make big changes (new configs, new recipes etc.) but this should get easier as I make more.

If you have any idea's or suggestions please let me know.