Application deployment with Chef

Transcript

1. Application deployment with Chef Igor Afonov

2. ‣ Ruby developer ‣ I’m participating in Chef development Developers

   Sys Admins DevOps I’m here About Me

3. Configuration Management Chef Quick Intro Application Deployment FAQ Q &

   A Agenda

4. Configuration Management

5. "Keep track of all the stuff you do to take

   a system from 'bare metal' to 'doing its job'." - Adam Jacob

6. ๏ Remember everything ๏ Keep notes in notepad ๏ Maintain

   wiki ๏ Bash scripts ๏ Automation frameworks

7. Opscode Chef

8. ๏ Configuration management framework ๏ Open source ๏ Created by

   Adam Jacob ๏ Maintained by Opscode

9. ๏ Client-server architecture ๏ Idempotence ๏ Declarative ๏ Ruby everywhere

10. Crash course

11. chef-server push pull VCS chef-client node chef-client node chef-client node

    server chef repository developer Workflow

12. cookbook recipe chef-repository resource resource resource Code structure

13. Resource

14. package 'apache2' do action :install provider Chef::Provider::Package::Apt version '2.4' end

15. Cookbook File Cron Deploy Directory Env Execute* File Git Group

    HTTP Request Ifconfig Link Log Mount Ohai Package PowerShell Script User Remote Directory Remote File Route Ruby Block SCM Script Service Subversion Template Bundled resources

16. Provider

17. package apt pacman macports Resource Providers Interface Implementation

18. service "redis" do action :start end Method call Parameter1 Parameter2

    # lib/chef/platform.rb - Chef::Platform :macosx => { :default => { ... :package => Chef::Provider::Package::Macports, :service => Chef::Provider::Service::Macosx, ... } } # lib/chef/provider/service/macosx.rb class Chef::Provider::Service::Macosx < Chef::Provider::Service::Simple def start if @current_resource.running Chef::Log.debug("#{@new_resource} already running, not starting") else shell_out!("launchctl load -w '#{@plist}'") end end end

19. Recipe

20. package "postfix" do action :install end %w{main master}.each do |config|

    template "/etc/postfix/#{config}.cf" do source "#{config}.cf.erb" owner "root" group "root" mode 0644 end end

21. Cookbook

22. cookbook |-attributes |-files |-libraries |-recipes |-templates |---metadata.rb

23. ๏ Cookbooks should be data-driven ๏ Do not hardcode anything

    ๏ Control behavior via: ๏ Attributes ๏ Databags ๏ Search

24. Node

25. ๏ Host that runs chef-client ๏ Has attributes ๏ Has

    run list

26. Role

27. name "mail-server" description "Installs and configures postfix MTA" default_attributes :postfix

    => { "mydomain" => "domain.com", "myorigin" => "domain.com" } run_list "recipe[postfix]"

28. Chef repository

29. chef-repo |-cookbooks |-data_bags |-roles |-environments |---Rakefile https://github.com/opscode/chef-repo

30. chef-server push pull VCS chef-client node chef-client node chef-client node

    server chef repository developer The big picture

31. ๏ Authenticate node ๏ Synchronize cookbooks ๏ Compile ๏ Converge

    chef-client run

32. ๏ Resource is a unit of work ๏ Provider take

    real action ๏ Recipe is collection of resources ๏ Cookbook is reusable set of recipes ๏ Code is pushed to chef-server ๏ Node pulls code from chef-server and runs it Recap

33. Deployment

34. ๏ Get the code from VCS ๏ Put the code

    to the right place ๏ Do some rituals Three easy* steps * Not true

35. Real-world example

36. internet nginx unicorn unicorn unicorn Simple Rails deployment

37. Get the code & put it to the right place

    application 'copycopter' do repository 'git@github.com:iafonov/copycopter-server.git' revision 'master' path '/var/www/apps/copycopter' end

38. Pick the SCM strategy application 'copycopter' do repository 'git@github.com:iafonov/copycopter-server.git' revision

    'master' path '/var/www/apps/copycopter' strategy :deploy_revision # :deploy_timestamped end

39. Set the code owner application 'copycopter' do repository 'git@github.com:iafonov/copycopter-server.git' revision

    'master' path '/var/www/apps/copycopter' strategy :deploy_revision owner 'deploy' group 'deploy' end

40. Install library dependencies application 'copycopter' do repository 'git@github.com:iafonov/copycopter-server.git' revision 'master'

    path '/var/www/apps/copycopter' strategy :deploy_revision owner 'deploy' group 'deploy' packages ['libxml2-dev', 'libxslt-dev'] end

41. Run migrations application 'copycopter' do repository 'git@github.com:iafonov/copycopter-server.git' revision 'master' path

    '/var/www/apps/copycopter' strategy :deploy_revision owner 'deploy' group 'deploy' packages ['libxml2-dev', 'libxslt-dev'] migrate true end

42. Restart service application 'copycopter' do repository 'git@github.com:iafonov/copycopter-server.git' revision 'master' path

    '/var/www/apps/copycopter' strategy :deploy_revision owner 'deploy' group 'deploy' packages ['libxml2-dev', 'libxslt-dev'] migrate true restart_command 'service copycopter restart' end

43. ๏ rails ๏ java_webapp ๏ tomcat ๏ django ๏ ...

    Sub-resources

44. Rails application 'copycopter' do ... rails do gems ['bundler'] database

    do username node['mysql']['username'] password node['mysql']['password'] database 'copycopter_production' end end end

45. Unicorn application 'copycopter' do ... rails do ... end unicorn

    do worker_processes 4 port 8080 end end

46. nginx application 'copycopter' do ... rails do ... end unicorn

    do ... end nginx_load_balancer do static_files '/public' => 'public' application_server_role 'copycopter_app_server' end end

47. ๏ before_deploy ๏ before_migrate ๏ before_symlink ๏ before_restart ๏ after_restart

    Callbacks

48. Run backups application 'copycopter' do ... before_deploy do execute 'run_backups'

    do command 'rsync ....' end end end

49. Notify monitoring system application 'copycopter' do ... before_deploy do execute

    'run_backups' do command 'rsync ....' end end after_restart do StatsD.gauge("#{node.name}.deploy") end end

50. ๏ Chef allows declaratively describe deploy process ๏ A lot

    of technology stacks are supported via sub-resources ๏ You can precisely control each step of process Recap

51. FAQ

52. When you should automate your infrastructure?

53. Which tool should you use?

54. What are benefits of using automation tools?

55. Q & A afonov@gmail.com http://iafonov.github.com @iafonov

56. Thank You! afonov@gmail.com http://iafonov.github.com @iafonov