How to Bundler (ROSSConf 2015)

ROSSConf brings developers together to learn about open source projects, and then work on them together with help from project team members. This talk explains how Bundler works and highlights some upcoming plans that could use help from contributors, and was given at ROSSConf 2015 in Berlin, Germany.

Transcript

1. how to Bundler
2. André Arko @indirect
6. let’s share ruby code
7. Gemfile gem “foo”
8. Terminal $ bundle install
9. Terminal $ bundle exec foo
10. done! pretty cool, right?
11. but… what just happened?
12. iiiiit’s History ⚔ Time
13. 1994 2000 2003 2009 dependency timeline require setup.rb RubyGems Bundler
14. require it loads the codes
15. def require(filename) eval File.read(filename) end
16. i’m sure it’s fine run code twice?
17. $LOADED_FEATURES = [] def require(filename) if $LOADED_FEATURES.include?(filename) return true end eval File.read(filename) $LOADED_FEATURES << filename end
18. probably fine too only absolute paths?
19. $LOAD_PATH = [] def require(filename) full_path = $LOAD_PATH.first do |path| File.exist?(File.join(path, filename)) end eval File.read(full_path) end
20. load paths are ⛄ pretty ❄ cool
21. but now we need… setup.rb
22. how do setup.rb? ruby setup.rb setup ruby setup.rb config ruby setup.rb install
23. use ruby libraries 1. Find a cool library 2. Download the library 3. Untar the library 4. Run `ruby setup.rb all`
24. no versions no uninstall but it’s fine, I’m sure
25. maybe a little bit incredibly tedious
26. what if you could… gem install gem uninstall gem list rails
27. bonus round! gem install rails -v 4.1 gem install rails -v 4.2 gem install rails -v 5.0
28. gem "rack", "1.0" require "rack"
29. $ rackup _1.2.2_ -p 3000
30. so many gems! 100,000 gems 1,000,000 versions
31. but gem apps don’t play well with others
32. welcome to the team here’s your machine we expect setting up to take a week
33. # config/application.rb […] config.gem “rack” config.gem “rails” config.gem “what?” […]
34. “why is this broken in production?” “dunno, it works on every developer machine” 3 days of debugging later… “oh, look, one production server has frobnitz 1.1.3, but the others have 1.1.4” “welp. that explains those exceptions ”
35. version conflicts gem install rails rails s cd ../other-project rails s
36. activation errors how common can they be, really?
37. $ rails s Gem::LoadError: can't activate rack (~> 1.0.0., runtime) for ["actionpack-2.3.5"], already activated rack-1.1.0 for ["thin-1.2.7"] activation errors
38. the moral runtime resolution install-time resolution
39. wait… how do we resolve at install-time?
41. addressable (2.3.7) arel (6.0.0) bcrypt (3.1.10) binding_of_caller (0.7.2) debug_inspector (>= 0.0.1) builder (3.2.2) byebug (3.5.1) columnize (~> 0.8) debugger-linecache (~> 1.2) slop (~> 3.6) celluloid (0.16.0) Gemfile.lock
42. bundle install my old friend 1. Read the Gemfile (and lock, if it's there) 2. Ask RubyGems.org for a list of every gem we need 2. Find gems allowed by the Gemfile that work together 3. Write down those versions in the lock for future installs 4. Install gems until every locked gem is installed
43. bundle exec everyone’s nemesis 1. Read the Gemfile (and lock, if it's there) 2a. Use locked gems if possible OR 2b. Find versions that work to put in the lock 3. Remove any existing gems the $LOAD_PATH 4. Add each gem in the lock to the $LOAD_PATH
44. pro tip no more bundle exec! $ bundle binstubs rspec-core $ bin/rspec repeat as needed for other gems
45. was that the end? in a word, no.
46. I want YOU to contribute 2 @bundlerio team@bundler.io
47. we have many plans • gathering gemfiles for a bundler benchmark • triaging github issues • add failing tests for bugs • improving our code! (check PullReview or
 Code Climate for ideas) • create a FAQ for bundler.io • build more librato graphs using our data • track how many projects a gem is used in • update the command docs on bundler.io • local gem server
48. We have a see you there! we have a guide CONTRIBUTING.md