Upgrade Rails 101 Philly.rb, April 2019

Who is this talk for? 2

Outline: Step #1; Exercise #1; Step #2; Exercise #2; and so on… 3

Goal: The Upgrade Roadmap 4

Ernesto Tagwerker (he/him) @etagwerker

Founder & Software Engineer at Ombu Labs

Founder & Software Engineer at FastRuby.io

Is upgrading a good idea?

Does your build pass? 9

Does your app have decent test coverage? 10

Exercise #1: Calculate Test Coverage

$ git clone [email protected]:fastruby/e-petitions.git If you don’t have an outdated Rails app

SimpleCov 13

14 # Gemfile group :test do gem 'simplecov', require: false end

15 # spec/spec_helper.rb if ENV['COVERAGE'] == 'true' require 'simplecov' SimpleCov.start 'rails' end

16 # Bash $ COVERAGE=true bundle exec rake

Exercise #1 Time:10 minutes 17

Is upgrading a good idea?

Upgrading is always* a good idea 19

Let’s assume your application is well covered 20

Pessimistic Dependencies Checkup

Dependencies should be pessimistic 22

23 # Gemfile (fixed version) source 'https://rubygems.org' gem 'rails', '4.2.7'

24 $ bundle update $ cat Gemfile.lock | grep rails rails (4.2.7)

25 # Gemfile (pessimistic versions) source 'https://rubygems.org' gem 'rails', '~> 4.2.7'

26 $ bundle update $ cat Gemfile.lock | grep rails rails (4.2.11.1)

Exercise #2: Relax your Gemfile

Analyze your Gemfile 28

Improve dependency declarations 29

30 $ bundle update

31 $ bundle exec rake

Does your build pass? 32

33 Exercise #2 Time:10 minutes

What happened? 34

Find Outdated Dependencies & Track Deprecation Warnings

“Couldn’t I just bump the version of Rails?” 36

How many outdated dependencies do you have? 37

Exercise #3: How outdated is your app?

39 $ bundle outdated Fetching gem metadata from https://rubygems.org/. Resolving dependencies..... Outdated gems included in the bundle: * actioncable (newest 5.2.3, installed 5.1.6) * actionmailer (newest 5.2.3, installed 5.1.6) * actionpack (newest 5.2.3, installed 5.1.6) * actionview (newest 5.2.3, installed 5.1.6) ...

40 # Gemfile group :development do gem 'ten_years_rails' end

41 $ bundle

42 $ bundle_report outdated redcarpet 3.0.0: released over 5 years ago (latest version, 3.4.0, released over 2 years ago) bootstrap-sass 3.3.7: released over 2 years ago (latest version 3.4.1, released about 2 months ago) ... mail 2.7.0: released over 1 year ago (latest version, 2.7.1, released 6 months ago) activesupport 5.1.6: released about 1 year ago (latest version, 5.2.3, released 11 days ago) railties 5.1.6: released about 1 year ago (latest version, 5.2. released 11 days ago) 0 gems are sourced from git 65 of the 102 gems are out-of-date (64%)

43 $ bundle_report compatibility --rails-version=5.2.0 0 gems incompatible with Rails 5.2.0 (this is for an app running Rails 5.1.4)

44 $ bundle_report compatibility --rails-version=6.0.0.beta3 => Incompatible with Rails 6.0.0.beta3 (with new versions that are compatible): These gems will need to be upgraded before upgrading to Rails 6.0.0.beta3. rails-controller-testing 1.0.2 - upgrade to 1.0.4 responders 2.4.0 - upgrade to 2.4.1 2 gems incompatible with Rails 6.0.0.beta3 (this is for an app running Rails 5.1.4)

45 # spec/rails_helper.rb require 'deprecation_tracker' RSpec.configure do |config| if ENV["DEPRECATION_TRACKER"] DeprecationTracker.track_rspec( config, shitlist_path: "spec/support/deprecation_warning.shitlist.json", mode: ENV["DEPRECATION_TRACKER"], transform_message: -> (message) { message.gsub("#{Rails.root}/", "") } ) end # ...

46 $ DEPRECATION_TRACKER=save bundle exec rake

47 Exercise #3 Time:15 minutes

What happened? 48

Trust The Process

Gradual version jumps 50

... ✅ 2.3 3.0 ✅ 3.0 3.1 ✅ 3.1 3.2 ✅ 3.2 4.0 ✅ 4.0 4.1 ✅ 4.1 4.2 ✅ 4.2 5.0 ✅ 5.0 5.1 ✅ 5.1 5.2 ✅ 5.2 6.0 51 Gemfile Gemfile.next { }

Every deprecation warning is a story 52

Every failing scenario is a story 53

Ship backwards- compatible changes first 54

Dual Boot & Start Upgrading

Enough talk, let’s bump that Rails version 56

57 $ next --init Created Gemfile.next (a symlink to your Gemfile). Your Gemfile has been modified to support dual-booting! There's just one more step: modify your Gemfile to use a newer version of Rails using the `next?` helper method. For example, here's how to go from 5.2.3 to 6.0: if next? gem "rails", "6.0.0" else gem "rails", "5.2.3" end

58 # Gemfile def next? File.basename(__FILE__) == "Gemfile.next" end source 'https://rubygems.org' gem 'rails', '~> 5.1.1’

59 # Gemfile if next? gem 'rails', '~> 5.2.3' else gem 'rails', '~> 5.1.4' end

60 $ BUNDLE_GEMFILE=Gemfile.next bundle install

Incompatibilities 61

62 $ BUNDLE_GEMFILE=Gemfile.next bundle install Bundler could not find compatible versions for gem "activesupport": In snapshot (Gemfile.lock): activesupport (= 4.2.1) In Gemfile: activeadmin was resolved to 1.0.0.pre4, which depends on arbre (>= 1.0.2, ~> 1.0) was resolved to 1.1.1, which depends on activesupport (>= 3.0.0) activeadmin was resolved to 1.0.0.pre4, which depends on inherited_resources (~> 1.6) was resolved to 1.7.0, which depends on ...

Failures 63

64 $ BUNDLE_GEMFILE=Gemfile.next bundle exec rake rake aborted! Bundler::GemRequireError: There was an error while trying to load the gem 'test_after_commit'. Gem Load Error is: after_commit testing is baked into rails 5, you no longer need test_after_commit gem Backtrace for gem load error is: /Users/etagwerker/.rvm/gems/ruby-2.4.5@petitions/gems/ test_after_commit-1.1.0/lib/test_after_commit.rb:4:in `' /Users/etagwerker/.rvm/rubies/ruby-2.4.5/lib/ruby/site_ruby/2.4.0/ bundler/runtime.rb:81:in `require' /Users/etagwerker/.rvm/rubies/ruby-2.4.5/lib/ruby/site_ruby/2.4.0/ bundler/runtime.rb:81:in `block (2 levels) in require' /Users/etagwerker/.rvm/rubies/ruby-2.4.5/lib/ruby/site_ruby/2.4.0/ bundler/runtime.rb:76:in `each'

65 # Gemfile # ... group :test do gem 'nokogiri' gem 'shoulda-matchers' gem 'pickle' gem 'test_after_commit' unless next? end

66 $ BUNDLE_GEMFILE=Gemfile.next bundle exec rake NoMethodError: undefined method `hide_action' for Delayed::Web::ApplicationController:Class # ./config/initializers/delayed_web.rb:10:in `block in ' # ./config/initializers/delayed_web.rb:7:in `class_eval' # ./config/initializers/delayed_web.rb:7:in `' # /Users/etagwerker/.rvm/gems/ruby-2.4.5@petitions/gems/ activesupport-5.0.7.2/lib/active_support/dependencies.rb:287:in `load' # /Users/etagwerker/.rvm/gems/ruby-2.4.5@petitions/gems/ activesupport-5.0.7.2/lib/active_support/dependencies.rb:287:in `block in load' # /Users/etagwerker/.rvm/gems/ruby-2.4.5@petitions/gems/ activesupport-5.0.7.2/lib/active_support/dependencies.rb:259:in `load_dependency'

67 # config/initializers/delayed_web.rb Delayed::Web::ApplicationController.class_eval do include Authentication, FlashI18n hide_action :admin_request? def admin_request? true end protected def admin_login_url main_app.admin_login_url end end

68 # config/initializers/delayed_web.rb Delayed::Web::ApplicationController.class_eval do include Authentication, FlashI18n protected def admin_request? true end def admin_login_url main_app.admin_login_url end end

Deprecation Warnings 69

70 $ BUNDLE_GEMFILE=Gemfile.next bundle exec rake DEPRECATION WARNING: The success? predicate is deprecated and will be removed in Rails 6.0. Please use successful? as provided by Rack::Response::Helpers. (called from block (3 levels) in at /Users/etagwerker/Projects/ ombulabs/fastruby.io/spec/controllers/ contacts_controller_spec.rb:20) .DEPRECATION WARNING: The success? predicate is deprecated and will be removed in Rails 6.0. Please use successful? as provided by Rack::Response::Helpers. (called from block (4 levels) in at /Users/etagwerker/Projects/ ombulabs/fastruby.io/spec/controllers/ contacts_controller_spec.rb:32) ..DEPRECATION WARNING: The success? predicate is deprecated and will be removed in Rails 6.0. Please use successful? as provided by Rack::Response::Helpers. (called from block (4 levels) in at /Users/etagwerker/Projects/ ombulabs/fastruby.io/spec/controllers/ contacts_controller_spec.rb:52) ..........

Find References To Deprecated API

https://edgeguides.rubyonrails.org/ upgrading_ruby_on_rails.html Official Guides

Unofficial Guides 73 1.https://fastruby.io/blog/rails/upgrades/upgrade-to-rails-3.html 2.https://fastruby.io/blog/rails/upgrades/upgrade-to-rails-3-1.html 3.https://fastruby.io/blog/rails/upgrades/upgrade-to-rails-3-2.html 4.https://fastruby.io/blog/rails/upgrades/upgrade-rails-from-3-2-to-4-0.html 5.https://fastruby.io/blog/rails/upgrades/upgrade-rails-from-4-0-to-4-1.html 6.https://fastruby.io/blog/rails/upgrades/upgrade-rails-from-4-1-to-4-2.html 7.https://fastruby.io/blog/rails/upgrades/active-record-5-1-api-changes.html 8.https://fastruby.io/blog/rails/upgrades/upgrade-rails-from-4-2-to-5-0.html 9.https://fastruby.io/blog/rails/upgrades/upgrade-rails-from-5-0-to-5-1.html 10.https://fastruby.io/blog/rails/upgrades/upgrade-rails-from-5-1-to-5-2.html

74 Exercise #4 Time: 20 minutes

What happened? 75

How To Stay Current

Add `bundler-audit` to your tests 77

Treat new deprecation warnings as exceptions 78

79 # Gemfile source 'https://rubygems.org' git_source(:github) do |repo_name| repo_name = "#{repo_name}/#{repo_name}" unless repo_name.include?("/") "https://github.com/#{repo_name}.git" end if next? gem 'rails', github: 'rails/rails' else gem 'rails', '~> 6.0.0.beta3' end

Thank you! @etagwerker 80

Resources 81 1.https://github.com/clio/ten_years_rails 2.https://github.com/alphagov/e-petitions 3.https://github.com/rubyperu/ready4rails 4.https://edgeguides.rubyonrails.org/upgrading_ruby_on_rails.html#the- upgrade-process 5.https://fastruby.io/blog/tags/upgrades 6.