20140406 loa days-tdd-with_puppet_tutorial

20140406 loa days-tdd-with_puppet_tutorial

• 1.
  TDD with Puppet ! LOADays 2014-04-06 Antwerp,BE! ! Garrett Honeycutt @learnpuppet [email protected] http://learnpuppet.com
• 2.
  # whoami
• 3.
  Where are we going? •Why test? • What makes a good module • Tools • SetupVM • Hack • Travis-ci • More Hacking 3
• 4.
  LearnPuppet.com • Training • 3day Intro course • 2 day advanced course • Consulting • Auditing 4
• 5.
  Why test? 5 • Confidenceto change things
• 6.
  Why test? 6 • Confidenceto change things • Know when you break something before deploying it
• 7.
  Why test? 7 • Confidenceto change things • Know when you break something before deploying it • Quickly test a matrix of Puppet and Ruby versions
• 8.
  Why test? 8 • Confidenceto change things • Know when you break something before deploying it • Quickly test a matrix of Puppet and Ruby versions • Test all OS’s without having to deploy it everywhere
• 9.
  Why test? 9 • Confidenceto change things • Know when you break something before deploying it • Quickly test a matrix of Puppet and Ruby versions • Test all OS’s without having to deploy it everywhere • Fast feedback
• 10.
  Why test? 10 • Confidenceto change things • Know when you break something before deploying it • Quickly test a matrix of Puppet and Ruby versions • Test all OS’s without having to deploy it everywhere • Prevent regression of old problems • Fast feedback
• 11.
  Why test? 11 • Confidenceto change things • Know when you break something before deploying it • Quickly test a matrix of Puppet and Ruby versions • Test all OS’s without having to deploy it everywhere • Prevent regression of old problems • Fast feedback • Even in an agile world, we still have design specs.
• 12.
  Why test first? •Puts a focus on what you want to accomplish. • Documents the functionality that you care about. • Makes you think about your design. • Save time by building the minimum viable product first. • You can refactor later. 12
• 13.
  What to test? •Each parameter • Each resource • Ensure that failure occurs when that’s expected • Conditional logic 13
• 14.
  What is actually tested? •Catalog is compiled with inputs such as setting values for facts and parameters • We test that things are or are not in the catalog • Simple :) 14
• 15.
  Semver • Explanation ofsemantic versioning - semver.org 15
• 16.
  What is 1.0.0 •README explains all parameters • Passes lint • Works with at least Ruby 1.8.7, 1.9.3, and 2.0.0 • Validates params • Tests all params • Tests all flows in logic 16
• 17.
  approach to writing modules •Write the README first, explaining all of your parameters and their valid values and their default values. • Add all of the parameters to your manifests with default values from the README. • Write the tests from the README. • Write just enough code to get your tests to pass. • Refactor as necessary. 17
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  18
• 21.
  Get VM • InstallVirtualBox - https://www.virtualbox.org/ • Install Vagrant - http://www.vagrantup.com/ • git clone https://github.com/ghoneycutt/learnpuppet-tdd-vagrant • cd learnpuppet-tdd-vagrant • vagrant up 21
• 22.
  Testing tools • Onlyif you are not using the providedVM $ sudo gem install -V puppet-lint rspec rspec-puppet puppetlabs_spec_helper --no-ri --no-rdoc • https://github.com/puppetlabs/puppet-syntax-vim • https://github.com/puppetlabs/puppet-syntax-emacs 22
• 23.
  RVM http://www.rvm.io/ ! • Allows youto easily switch between multiple versions of Ruby 23
• 24.
  Ruby Versions • 1.8.7 •1.9.3 • 2.0.0 • 2.1.0 (Coming with Puppet v3.5.0) 24
• 25.
  rspec-puppet http://rspec-puppet.com/ Thanks,Tim! 25
• 26.
  Puppet Module Skeleton • $git clone https://github.com/ghoneycutt/puppet- module-skeleton • $ mkdir -p `puppet config print vardir`/puppet- module/skeleton/ • $ rsync -avp --exclude .git puppet-module- skeleton/ `puppet config print vardir`/puppet- module/skeleton/ 26
• 27.
  Create a module •generate motd module $ puppet module generate forgename-motd 27
• 28.
  Components ghoneycutt-motd ghoneycutt-motd/.fixtures.yml ghoneycutt-motd/.gitignore ghoneycutt-motd/.travis.yml ghoneycutt-motd/Gemfile ghoneycutt-motd/LICENSE ghoneycutt-motd/Modulefile ghoneycutt-motd/README.md ghoneycutt-motd/Rakefile ghoneycutt-motd/manifests ghoneycutt-motd/manifests/init.pp ghoneycutt-motd/spec ghoneycutt-motd/spec/classes ghoneycutt-motd/spec/classes/init_spec.rb ghoneycutt-motd/spec/fixtures ghoneycutt-motd/spec/fixtures/manifests ghoneycutt-motd/spec/fixtures/manifests/site.pp ghoneycutt-motd/spec/fixtures/modules ghoneycutt-motd/spec/spec_helper.rb 28
• 29.
  Components ghoneycutt-motd ghoneycutt-motd/.fixtures.yml ghoneycutt-motd/.gitignore ghoneycutt-motd/.travis.yml ghoneycutt-motd/Gemfile ghoneycutt-motd/LICENSE ghoneycutt-motd/Modulefile ghoneycutt-motd/README.md ghoneycutt-motd/Rakefile ghoneycutt-motd/manifests ghoneycutt-motd/manifests/init.pp ghoneycutt-motd/spec ghoneycutt-motd/spec/classes ghoneycutt-motd/spec/classes/init_spec.rb ghoneycutt-motd/spec/fixtures ghoneycutt-motd/spec/fixtures/manifests ghoneycutt-motd/spec/fixtures/manifests/site.pp ghoneycutt-motd/spec/fixtures/modules ghoneycutt-motd/spec/spec_helper.rb 29
• 30.
  .fixtures.yml • List allof your dependencies from Modulefile 30
• 31.
  Gemfile • Used byBundler 31
• 32.
  .travis.yml • Configure travis-ci.org 32
• 33.
  spec_helper.rb • Code thatis run before your spec tests. • Configures the spec testing environment. 33
• 34.
  Rakefile • Validate syntax rakevalidate ! • Validate style rake lint 34
• 35.
  Rakefile • show alltasks rake -T 35
• 36.
  rake spec • rakespec calls • rake spec_prep • rake spec_standalone • rake spec_clean 36
• 37.
  run tests $ SPEC_OPTS="--formatdocumentation" rake spec_standalone 37
• 38.
  first test it { shouldcontain_file('motd').with({ 'ensure' => 'file', 'path' => '/etc/motd', 'owner' => 'root', 'group' => 'root', 'mode' => '0644', 'content' => nil, }) } 38
• 39.
  run tests • Itfails! Now let’s fill in the code. 39
• 40.
  testing params • Eachattribute of the file resource should be configurable through params. • Let’s test for values that should should work as well as what should produce an error. 40
• 41.
  testing paramsdescribe 'withpath specified' do context 'as a valid path' do let(:params) { { :path => '/usr/local/etc/motd' } } ! it { should contain_file('motd').with({ 'path' => '/usr/local/etc/motd', }) } end ! context 'as an invalid path' do let(:params) { { :path => 'invalid/path' } } ! it 'should fail' do expect { should contain_class('motd') }.to raise_error(Puppet::Error) end end 41
• 42.
  testing file content describe'with content parameter specified' do let(:params) { { :content => "Welcome to puppet.learnpuppet.comnnHave Fun!n" } } ! ! it { should contain_file('motd').with_content( %{Welcome to puppet.learnpuppet.com ! Have Fun! }) } end 42
• 43.
  reading tests $ grep-ie describe -e context spec/classes/init_spec.rb describe 'motd' do context 'with default values for all parameters' do describe 'with motd_file parameter specified' do context 'as a valid path' do context 'as an invalid path' do describe 'with motd_content parameter specified' do 43
• 44.
  Exercise Test all params •All attributes of file resource should be configurable. • Write tests first. • Then add code to the module. 44
• 45.
  four digit mode describe'with motd_mode specified' do context 'as a valid four digit entry' do let(:params) { { :mode => '0755' } } ! it { should contain_file('motd').with({ 'mode' => '0755', }) } end ! context 'as an invalid three digit entry' do let(:params) { { :mode => '755' } } ! it 'should fail' do expect { should contain_class('motd') }.to raise_error(Puppet::Error,/^motd::mode must be a four digit string./) end end end 45
• 46.
  for loops ['666','66666','invalid',true].each do|mode| context "as invalid value #{mode}" do let(:params) { { :motd_mode => mode } } ! it 'should fail' do expect { should contain_class('motd') }.to raise_error(Puppet::Error,/^motd::mode must be a four digit string./) end end end 46
• 47.
  Exercise Validate mode • Validatemode with validate_re() https://github.com/puppetlabs/puppetlabs-stdlib/tree/3.2.0#validate_re • Test your regex at http://rubular.com/ 47
• 48.
  resource relationships# package it{ should contain_package('ntp_package').with({ ... }) } ! # file it { should contain_file('ntp_config').with({ ... 'require' => 'Package[ntp]', }) } ! # service it { should contain_service('ntp_service').with({ ... 'subscribe' => 'File[ntp_config]', }) } 48
• 49.
  file content # checkfor a specific line ! it { should contain_file('ntp_conf').with_content(/^tinker panic 0$/) } 49
• 50.
  file content # whatif the whole line is optional? # in this case we test that it is not present ! it { should_not contain_file('ntp_conf').with_content(/^tinker panic 0$/) } 50
• 51.
  Exercise ntp module • Usethe last few slides to guide you on a module for NTP • Do the minimum amount of work to get the tests to pass. • Copy /etc/ntp.conf to your module as a starting place 51
• 52.
  specify facts context 'withdefault values for parameters on EL 6' do let(:facts) do { :osfamily => 'RedHat', :lsbmajdistrelease => '6', } end end 52
• 53.
  Exercise add OS tontp • Add support for another OS.This OS should have at least a different name for the package or service. 53
• 54.
  54 GitHub HowTo
• 55.
  Travis-ci.org • Free! • Matrixtesting • Integrates with GitHub • Tests every pull request automatically • Free! 55
• 56.
  .travis.yml--- env: - PUPPET_VERSION=3.3.2 - PUPPET_VERSION=3.4.2 notifications: email:false rvm: - 1.8.7 - 1.9.3 - 2.0.0 language: ruby before_script: "gem install --no-ri --no-rdoc bundler" script: 'bundle exec rake validate && bundle exec rake lint && SPEC_OPTS="--format documentation" bundle exec rake spec' gemfile: Gemfile 56
• 57.
  57 Integrate with Travis
• 58.
  Test functions # lib/puppet/parser/functions/yell.rb modulePuppet::Parser::Functions newfunction(:yell, :type => :rvalue, :doc => <<-EOS Takes one argument, a string to be capitalized. Returns the string in all caps. EOS ) do |args| raise(Puppet::ParseError, "yell(): Wrong number of arguments " + "given (#{args.size} for 1)") if args.size != 1 args[0].upcase end end 58
• 59.
  Test functions # spec/functions/yell_spec.rb require'spec_helper' describe 'yell' do it 'should run with correct number of arguments (1)' do should run.with_params('hello world').and_return('HELLO WORLD') end ! it 'should fail with no arguments' do should run.with_params().and_raise_error(Puppet::ParseError) end ! it 'should fail with more than one argument (2)' do should run.with_params('too','many').and_raise_error(Puppet::ParseError) end end 59
• 60.
  Defines# spec/defines/mkdir_p_spec.rb require 'spec_helper' describe'common::mkdir_p' do context 'should create new directory' do let(:title) { '/some/dir/structure' } ! it { should contain_exec('mkdir_p-/some/dir/structure').with({ 'command' => 'mkdir -p /some/dir/structure', 'unless' => 'test -d /some/dir/structure', }) } end ! context 'should fail with a path that is not absolute' do let(:title) { 'not/a/valid/absolute/path' } ! it do expect { should contain_exec('mkdir_p-not/a/valid/absolute/path').with({ 'command' => 'mkdir -p not/a/valid/absolute/path', 'unless' => 'test -d not/a/valid/absolute/path', }) }.to raise_error(Puppet::Error) end end end 60
• 61.
  Exercise Defines • Create adefine,‘say’, that takes a param,‘msg’ or if msg is not sent, use the title and pass that to a notify{} resource. • Write tests first, then write the define. • Bonus to create your own function to run on the msg, such as making it all lower case or l33t sp34k. 61
• 62.
  Hashes • https://github.com/ghoneycutt/puppet-module-vim/blob/master/ spec/classes/init_spec.rb 62
• 63.
  Exercise refactor ntp • Refactorntp module to use a hash to specify differences between OS’s 63
• 64.
  TDD with Puppet ! LOADays 2014-04-06 Antwerp,BE! ! Garrett Honeycutt @learnpuppet [email protected] http://learnpuppet.com