pburkholder / pdb_motd Goto Github PK

TDD for Chef Cookbooks: Getting Started

Prerequisites:

• ChefDK:

  curl https://omnitruck.chef.io/install.sh |
    sudo bash -s -- -c current -P chefdk
  eval "$(/opt/chefdk/bin/chef shell-init bash)"
  

• git:

  git clone https://github.com/pburkholder/pdb_motd.git
  cd pdb_motd
  

• Vagrant

Nordstom's chefDK bootstrap cookbook: https://github.com/Nordstrom/chefdk_bootstrap

curl https://raw.githubusercontent.com/Nordstrom/chefdk_bootstrap/master/bootstrap | bash

Use 'kitchen-dokken' for testing

• Docker Toolbox, then

docker-machine create --driver virtualbox default
eval "$(docker-machine env default)"

• In this working dir:

  chef gem install kitchen-dokken
  export KITCHEN_LOCAL_YAML=.kitchen.dokken.yml
  kitchen create # should do all the background image downloads, takes a while
  

Rationale for this cookbook demo:

• Inductive Learners
• Examples > Theory
• Start simple (or even trivial)

User story from Legal:

• As user connecting via SSH to a node,
• I expect to see a login message,
• This system is the property of DevOpsDC

The last developer had a 1/2 completed cookbook:

• recipes/default.rb with attributes for path, message:

  file node['motd']['path'] do
    content node['motd']['message']
  end
  

• Rakefile with test tasks
• Tests in:

  spec/unit/recipes/default_spec.rb
  test/integration/default/inspec/default_spec.rb
  

Plan of Attack:

• Look at the tests; try to understand them
• Run the test suite
  • if something breaks, fix it
  • repeat until tests pass
• Do TDD for new ownership with above steps

Plan of Attack:

• Look at the tests; try to understand them
• Run the test suite
  • if something breaks, fix it
  • repeat until tests pass
• Do TDD for new ownership with above steps

Review ChefSpec default_spec.rb

spec/unit/recipes/default_spec.rb

require 'spec_helper'

describe 'pdb_motd::default' do
  let(:chef_run) {
    ChefSpec::SoloRunner.new.converge(described_recipe)
  }

  it 'should create MOTD' do
    expect(chef_run).to render_file('/etc/motd')
      .with_content('Property of DevOpsDC')
  end
end

Review Integration default_spec.rb

test/integration/default/inspec/default_spec

require 'inspec'

describe file('/etc/motd') do
  its(:content) { should match(/Property of DevOpsDC/) }
end

Rake default task:

rake -n
** Invoke default (first_time)
** Invoke cop (first_time)
** Execute (dry run) cop
** Invoke foodcritic (first_time)
** Execute (dry run) foodcritic
** Invoke spec (first_time)
** Execute (dry run) spec
** Execute (dry run) default

Plan of Attack:

• Look at the tests; try to understand them
• Run the test suite
  • if something breaks, fix it
  • repeat until tests pass
• Do TDD for new ownership with above steps

Demo - rake

Demo - rake kitchen

kitchen login
/opt/chef/embedded/bin/chef-client \
  -z -c /opt/kitchen/client.rb \
  -j /opt/kitchen/dna.json -l warn -F doc

Plan of Attack:

• Look at the tests; try to understand them
• Run the test suite
  • if something breaks, fix it
  • repeat until tests pass
• Do TDD for new ownership with above steps

Demo

Recap: Plan of Attack:

• Look at the tests; try to understand them
• Run the test suite
  • if something breaks, fix it
  • repeat until tests pass
• Do TDD for new content with above steps

Summary:

• Chef is Ruby
• We use TDD when developing Ruby, including
  • Rubocop/Foodcritic: style
  • Rspec/ChefSpec: unit testing
  • Test-Kitchen: integration testing

DISCUSSION: Why does Rakefile use shell commands instead of Ruby tasks?

So beginners try each of the commands in isolation, e.g.:

rubocop
rspec
foodcritic .

Fini.

Presentation prerequisites (for OsX)

brew install npm
npm install -g reveal-md
reveal-md README.md