Crafting Gems: RailsConf 2013

Gems underpin almost every piece of Ruby code we write – and so, being able to write your own gems is not only incredibly useful, it provides an avenue for code reuse and open source sharing.

During this session, Pat will talk about the ecosystem around gems and the knowledge required to write your own gems. He’ll also cover some of the tools available to assist with this, along with ideal approaches and best practices for gem development.

Transcript

1. Cut and Polish A Guide to Crafting Gems
2. Pat Allan @pat freelancing-gods.com
5. Say Hello!
6. “Use rubygems to publish your gem to rubygems”
7. “Use rubygems to publish your gem to rubygems”
8. “Use gem to publish your gem to rubygems”
9. “Use gem to publish your gem to rubygems”
10. “Use the gem command to publish your gem to rubygems.org”
11. noun a precious or semiprecious stone, esp. when cut and polished or engraved. |jem| gem
12. noun a packaged code library written in the Ruby programming language. |jem| gem
13. noun a command line executable distributed with the RubyGems package manager. |jem| gem
14. noun a package manager for Ruby libraries. |ˈro͞obējemz| rubygems
15. noun a website that stores published versions of Ruby gems. |ˈro͞obējemz| rubygems
16. Why?
17. Why? re-use code
18. Why? easy to install
19. Why? easy to share
20. History
21. History 2003 rubyforge.org
22. History 2004 rubygems
23. “If you have libraries you would like to include, please send the gem les to either myself or Rich Kilmer” Chad Fowler, 15 March 2004
24. History gems were magical
25. History permission was required
26. History 2009 gemcutter.org
27. History anyone can publish
28. History rubygems.org
29. Gemspecs
30. Gemspecs pdx.gemspec
31. # pdx.gemspec Gem::Specification.new do |s| s.name = ‘pdx’ s.version = ‘0.0.1’ s.authors = [‘Pat Allan’] s.email = [‘pat@email.com’] s.homepage = ‘’ s.summary = ‘RailsConf Gem’ s.description = ‘’ s.files = [...] s.test_files = [...] s.executables = [...] end
32. s.name = ‘pdx’ Naming
33. Naming # name ‘will_paginate’ # requiring require ‘will_paginate’ # Class/Module WillPaginate
34. Naming # name ‘cucumber-rails’ # requiring require ‘cucumber/rails’ # Class/Module Cucumber::Rails
35. Versions s.version = ‘0.0.1’
36. Versions s.version = ‘Major.Minor.Release’
37. Versions Major Versions
38. Versions Minor Versions
39. Versions Release Versions
40. Versions Reference
41. Versions # lib/pdx/version.rb module PDX VERSION = ‘0.0.1’ end
42. Versions # pdx.gemspec require ‘pdx/version’ # ... s.version = PDX::VERSION
43. Versions VERSION = ‘1.0.0.beta1’
44. Authors, Emails & Homepage s.authors = [‘Pat Allan’] s.email = [‘pat@email.com’] s.homepage = ‘https:// github.com/pat/pdx’
45. Summary & Description s.summary = ‘RailsConf Gem’ s.description = ‘All the Ruby code’
46. Files s.files = [ ‘lib/pdx.rb’, ‘lib/pdx/version.rb’, ‘README.textile’, ‘LICENCE’ ]
47. Files lib/pdx.rb
48. Files PDX::RailsConf lib/pdx/rails_conf.rb PDX::Hipster lib/pdx/hipster.rb
49. Files # Don’t do this lib/pdx.rb lib/rails_conf.rb lib/hipster.rb
50. Information Files README
51. Information Files LICENCE
52. Information Files HISTORY
53. Test Files s.test_files = [ ‘spec/pdx_spec.rb’, ‘spec/spec_helper.rb’ ]
54. Test Files Beware Large Test Suites
55. Test Files Travis CI
56. Executables s.executables = [ ‘bin/pdx’ ]
57. Executables #!/usr/bin/env ruby require ‘pdx’ PDX::CLI.run
58. # pdx.gemspec Gem::Specification.new do |s| s.name = ‘pdx’ s.version = ‘0.0.1’ s.authors = [‘Pat Allan’] s.email = [‘pat@email.com’] s.homepage = ‘’ s.summary = ‘RailsConf Gem’ s.description = ‘’ s.files = [...] s.test_files = [...] s.executables = [...] end
59. Dependencies s.add_runtime_dependency ‘rails’, ‘>= 3.0.0’
60. Dependencies s.add_development_dependency ‘rspec’, ‘>= 2.6.0’
61. Dependencies Dependency Versions
62. Dependencies s.add_runtime_dependency ‘rails’, ‘~> 3.1’
63. Dependencies ~>
64. Dependencies ~> 3.1 == [>= 3.1 && < 4.0] ~> 3.0.3 == [>= 3.0.3 && < 3.1]
65. Dependencies s.add_development_dependency ‘rspec’, ‘= 2.6.0’
66. Rake Tasks
67. # run tests rake spec # generate documentation rake yard # default task should run tests rake
68. Railties
69. Rails Railties class PDX::Railtie < Rails::Railtie rake_tasks do load File.expand_path( '../tasks.rb', __FILE__ ) end end
70. Engines
71. Rails Engines class PDX::Engine < Rails::Engine engine_name :pdx paths['app/controllers'] << 'lib/pdx/controllers' end
72. Publishing
73. Publishing gem build pdx.gemspec #=> pdx-0.0.1.gem
74. Gem Files .gem == .tar
75. Publishing gem push pdx-0.0.1.gem
76. Publishing Permanent
77. Publishing (Don’t) Yank
78. Publishing MRI 1.9 Caution
79. Community
80. Community Support
81. Community GitHub
82. Community Releases
83. Bundler
84. Bundler Recommended
85. Bundler Not Required
86. Bundler # Gemfile source ‘https://rubygems.org’ gemspec
87. Bundler # Gemfile gemspec gem ‘mysql2’, :platform => :ruby gem ‘jdbc-mysql’, :platform => :jruby
88. Bundler rake release
89. Bundler # Rakefile Bundler::GemHelper. install_tasks
90. Tools
91. Tools Hoe
92. Tools Jeweler
93. Examples
94. Examples bundle open pdx
95. Thank You Questions?
96. http://railsconftutorials.com http://bit.ly/pat-gems Tutorial Instructions here: Gems available here: