Internationalization & Localization

As presented at Argentina RubyConf 2012. Screencast (with built-in, low quality mic) at http://dl.dropbox.com/u/69001/i18n%20argentina%20rubyconf.mov

Transcript

1. Internationalization & Localization Stop making that face. 1 Jeff Casimir / @j3
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4. Hooray, RubyConf Argentina! You going to present in English? People might not understand my jokes in English. In your Spanish, they might not understand anything! anything!
5. A Dangerous Journey 5
6. Terms 6 ▪i18n - Internationalization ▪l10n - Localization
7. Why A Business Cares 7 ▪Localization provides a better UX ▪Better UX = More Customers ▪More Customers = More Profits*
8. But what’s in it for me?
9. Why Developers Care 9 Better Code
10. Roadmap to Multi-Language Support 1. Internationalize 2. Localize 3. Determine Locale 10
11. Step 1: Internationalize 11
12. 12 An Average Controller Action def create @article = Article.new(params[:article]) if @article.save flash[:notice] = "Article was created." redirect_to articles_path else flash[:notice] = "The article could not be saved!" render :new end end
13. 13 Do you like MAGIC?
14. Copyedit Commits
15. 15 Magic Data in a Controller def create @article = Article.new(params[:article]) if @article.save flash[:notice] = "Article was created." redirect_to articles_path else flash[:notice] = "The article could not be saved!" render :new end end
16. Lookup Dictionary 16
17. 17 en: article: deleted: "Article has been deleted." error: "Article failed to save." created: "Article created successfully." new: "New Article" update: "Save Changes" create: "Save Article" comment: created: "Comment posted, you're internet famous." spam: "Burn your own face off, spammer." create: "Post Comment" status: moderation: "Comment is pending moderation." approved: "Comment approved." A YAML Dictionary
18. t and I18n.t 18 t 'article.deleted' t 'comment.status.approved' I18n.t 'comment.created'
19. Structuring Keys 19 ▪Keep the keys short ▪Don’t just snake-case the text ▪Focus on core meaning ▪Screw reusability
20. 20 en: article: deleted: "Article has been deleted." error: "Article failed to save." created: "Article created successfully." new: "New Article" update: "Save Changes" create: "Save Article" comment: created: "Comment posted, you're internet famous." spam: "Burn your own face off, spammer." create: "Post Comment" status: moderation: "Comment is pending moderation." approved: "Comment approved." Simple Keys, Simple Strings
21. Draper 21
22. 22 Magic Data in a Controller def create @article = Article.new(params[:article]) if @article.save flash[:notice] = "Article was created." redirect_to articles_path else flash[:notice] = "The article could not be saved!" render :new end end
23. 23 Controller Without Magic def create @article = Article.new(params[:article]) if @article.save flash[:notice] = t 'article.save.success' redirect_to articles_path else flash[:notice] = t 'article.save.failure' render :new end end
24. Automatic Lookups with ActiveRecord
25. 25 Magic Data in a Model class Article < ActiveRecord::Base validates_length_of :body, :min => 100 :message => " must be at least 100 characters bro." def self.recent order('created_at DESC').limit(10) end def attribution "written by #{author.full_name}" end end
26. Automatic Lookup Paths 26 activerecord.errors.models.[model_name].attributes.[attribute_name] activerecord.errors.models.[model_name] activerecord.errors.messages errors.attributes.[attribute_name] errors.messages
27. Rails Guide’s Validation Keys 27
28. Validation Message Lookup 28 en: activerecord: errors: models: article: attributes: title: blank: "The article needs a title!"
29. 29 Validation with a :message class Article < ActiveRecord::Base validates_presence_of :title, :message => "The article needs a title." def self.recent order('created_at DESC').limit(10) end def attribution "written by #{author.full_name}" end end
30. 30 Validation Using Auto-Lookup class Article < ActiveRecord::Base validates_presence_of :title def self.recent order('created_at DESC').limit(10) end def attribution "written by #{author.full_name}" end end
31. Aut-o-matic! 31 a = Article.new(:body => "boo") # => #<Article id: nil, title: nil, body: "boo"...> a.save # => false a.errors.first.inspect # => "[:title, \"The article needs a title!\"]" a.errors.first.last # => "The article needs a title!"
32. Attribute & Model Names 32 en: activerecord: attributes: article: title: "Title" comment: body: "Your Comment" label and other form helpers use them automatically
33. en: activerecord: attributes: article: title: "Title" comment: body: "Your Comment" errors: models: article: attributes: title: blank: "The article needs a title!"
34. The process of internationalization will improve your code, regardless of localization. 34
35. 2. Localizing User Content 35
36. 36 Static Dictionary Was Easy en: article: deleted: "Article has been deleted." error: "Article failed to save." created: "Article created successfully." new: "New Article" update: "Save Changes" create: "Save Article" comment: created: "Comment posted, you're internet famous." spam: "Burn your own face off, spammer." create: "Post Comment" status: moderation: "Comment is pending moderation." approved: "Comment approved."
37. Challenges with User-Generated Content 37 ▪ Creating multiple translations ▪ Managing the content import/export ▪ Keeping translations in sync
38. CopyCopter 38
39. Globalize3 39
40. Locale - localeapp.com 40
41. Step 3: Per-Request Locale 41
42. A Quick Story about BDD 42
43. github/jcasimir/locale_setter 43
44. Locale-Selection Strategies 44 1. Geolocation 2. Browser Preferences 3. URL Parameters 4. Account Preferences 5. Default
45. Geolocation 45
46. 46 Browser Preferences
47. HTTP_ACCEPT_LANGUAGE 47
48. HTTP_ACCEPT_LANGUAGE 48 class ArticlesController < ApplicationController def show render :text => request.env['HTTP_ACCEPT_LANGUAGE'] end end
49. en;q=0.8 , , Accept-Language Formatting 49 en-US es;q=0.2
50. Accept-Language Formatting 50 “US English for Full Experience” “Generic English at 80% Quality” “Generic Spanish at 20% Quality” en;q=0.8 es;q=0.2 en-US
51. 51 Parsing Accept-Language # In an imaginary controller context... accepts = request.env["HTTP_ACCEPT_LANGUAGE"] # => "en,en-US;q=0.8,es;q=0.2" accepts.downcase.scan(/([\w-]{2,})/).map(&:first) # => ["en", "en-us", "es"]
52. module  LocaleSetter    module  HTTP        def  self.for(accept_language)            LocaleSetter::Matcher.match(AcceptLanguageParser.                                                      parse(accept_language))        end        module  AcceptLanguageParser            LOCALE_SEPARATOR  =  ','            WEIGHT_SEPARATOR  =  ';'            def  self.parse(accept_language)                locale_fragments  =  accept_language.split(LOCALE_SEPARATOR)                weighted_fragments  =  locale_fragments.                                map{|f|  f.split(WEIGHT_SEPARATOR)}                sorted_fragments  =  weighted_fragments.sort_by{|f|  -­‐f.last.to_f  }                sorted_fragments.map{|locale,  weight|  locale}            end        end    end end
53. 53 Querying Available Locales I18n.available_locales # => [:en, :"en-us", :es, :"es-ar"]
54. Matching Available Locales 54 ▪ Find the user’s accepted locales ▪ Symbolize them ▪ Compare with the supported locales ▪ Find the first match in order of their preference
55. module  LocaleSetter    module  Matcher        def  self.match(requested)            (requested  &  I18n.available_locales).first        end    end end
56. URL Parameters 56
57. Why Use URL Parameters? 57 ▪Easy to switch locales for development / debugging ▪Copied URLs will maintain state for sharing*
58. Pulling it out of the URL 58 class ApplicationController < ActionController::Base before_filter :set_locale private def set_locale I18n.locale = params[:locale] end end
59. Danger! 59 symbols = Symbol.all_symbols # => [...] I18n.locale = "garbage_from_a_user" # => "garbage_from_a_user" I18n.locale # => :garbage_from_a_user Symbol.all_symbols - symbols # => [:garbage_from_a_user]
60. module  LocaleSetter    include  LocaleSetter::Rails    #...    def  from_params        if  respond_to?(:params)  &&  params[:locale]            LocaleSetter::Param.for(params[:locale])        end    end end module  LocaleSetter    module  Param        def  self.for(param)            LocaleSetter::Matcher.match([param])        end    end end
61. module  LocaleSetter    module  Matcher        def  self.match(requested,  against  =  available)            matched  =  (sanitize(requested)  &  against).first            matched.to_sym  if  matched        end        def  self.available            I18n.available_locales.map(&:to_s)        end        #  sanitize  methods  are  just  for  case  &  whitespace        #  ...    end end
62. The Link Problem 62
63. Modifying default_url_options 63 module  LocaleSetter    module  Rails        def  default_url_options(options  =  {})            if  i18n.locale  ==  i18n.default_locale                options            else                {:locale  =>  i18n.locale}.merge(options)            end        end        #  ...    end end
64. User Preferences 64
65. Store in the DB 65 rails generate migration \ add_locale_to_users locale:string
66. module  LocaleSetter    module  User        def  self.for(user)            if  user  &&  user.respond_to?(:locale)  &&                    user.locale  &&  !user.locale.empty?                LocaleSetter::Matcher.match(user.locale)            end        end    end end module  LocaleSetter    #  ...    def  from_user        if  respond_to?(:current_user)  &&  current_user            LocaleSetter::User.for(current_user)        end    end end
67. Composite Strategy 67
68. Lookup Chain 68 1.URL parameter 2.User Preference 3.Browser 4.Default
69. module  LocaleSetter    include  LocaleSetter::Rails    def  self.included(controller)        if  controller.respond_to?(:before_filter)            controller.before_filter  :set_locale        end    end    def  set_locale        i18n.locale  =  from_params  ||                                    from_user      ||                                    from_http      ||                                    i18n.default_locale    end    def  from_user        if  respond_to?(:current_user)  &&  current_user            LocaleSetter::User.for(current_user)        end    end
70. github/jcasimir/locale_setter 70
71. Bonus Round: White-Boxing & I18n 71
72. Normal Application Layout 72 <head> <title>AssetSample</title> <%= stylesheet_link_tag "application", :media => "all" %> <%= javascript_include_tag "application" %> <%= csrf_meta_tags %> </head>
73. Application Layout w/ I18n 73 <head> <title>AssetSample</title> <%= stylesheet_link_tag t("stylesheet"), :media => "all" %> <%= javascript_include_tag t("javascript") %> <%= csrf_meta_tags %> </head>
74. Application Layout w/ I18n 74 client_1: stylesheet: "client1_stylesheet" javascript: "client1_javascript" client_2: stylesheet: "client2_stylesheet" javascript: "client2_javascript"
75. !!! $$$ PROFIT $$$ !!! 75
76. Recap 76
77. Step 1: Internationalize 77
78. Step 2: Localize Content 78
79. Step 3: Determine Locale 79
80. Hack I18n Beyond Translations 80
81. Internationalization & Localization 81 Jeff Casimir / @j3
82. Scraps 82
83. Localize Functional Text 83
84. In the View Layer 84 <%= errors_for(@article) %> module ApplicationHelper def errors_for(subject) if subject.errors render(:partial => 'common/errors', :locals => {:errors => subject.errors}) end end end
85. Errors Partial 85 <%= if errors.any? %> <ul class='errors' > <% errors.each do |e| <li><%= e.last %></li> <% end %> </ul> <% end %>
86. 86 No Magic def create @article = Article.new(params[:article]) if @article.save flash[:notice] = t 'article.save.success' redirect_to articles_path else render :new end end
87. Interpolation 87 en: generic: deleted: "%{subject} has been deleted." error: "%{subject} failed to save." t 'generic.deleted', :subject => "Comment" WAT?!
88. Interpolation 88 en: models: comment: "Comment" article: "Article" generic: deleted: "%{subject} has been deleted." error: "%{subject} failed to save." t 'generic.deleted', :subject => t('models.comment')
89. class ActiveRecord::Base def self.translates(*args) args.each do |method| define_method method do target = "#{method}_#{I18n.locale}" respond_to?(target) ? send(target) : attribute(method) end end end end class Article < ActiveRecord::Base translates :title, :body end