Reduce Vagrant code duplication by using functions

Aug 27, 2016 linux

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I use Vagrant for most of my server management. One thing I noticed is that my Vagrantfile can get pretty large - especially if I have multiple environments that share the same configuration.

Then it occurred to me - this is just a ruby file! So, I decided to use a function to limit down some of my configuration.

I have a lot of duplication around the sections of my file where I configure an ansible provisioner.

For example, see this configuration:

local.vm.provision "ansible" do |ansible|
  ansible.playbook = "ansible/playbook.yml"
  ansible.host_key_checking = true
  ansible.sudo = true
    
  ansible.host_key_checking = false
  ansible.extra_vars = {
    server_name: local.vm.hostname,
    server_env: "development"
  }
end

The first three lines in this particular configuration are used for every configuration in my file (in some instances, there are many more files). So, instead, I decided to create the following method at the top of the configuration block:

def shared_ansible_config(ansible)
  ansible.playbook = "ansible/playbook.yml"
  ansible.host_key_checking = true
  ansible.sudo = true
end

Then, I called this function while passing in the configuration object to it in my provision statement like so:

local.vm.provision "ansible" do |ansible|
  shared_ansible_config ansible
    
  ansible.host_key_checking = false
  ansible.extra_vars = {
    server_name: local.vm.hostname,
    server_env: "development"
  }
end

There - less code duplication! :)