PERF: Much more performant, multisite aware I18n overrides

config/initializers/i18n.rb

@@ -3,5 +3,6 @@
 require 'i18n/backend/discourse_i18n'
 I18n.backend = I18n::Backend::DiscourseI18n.new
 I18n.config.missing_interpolation_argument_handler = proc { throw(:exception) }
+I18n.reload!
 
 MessageBus.subscribe("/i18n-flush") { I18n.reload! }

db/migrate/20140120155706_add_lounge_category.rb

@@ -2,7 +2,7 @@ class AddLoungeCategory < ActiveRecord::Migration
   def up
     return if Rails.env.test?
 
-    I18n.backend.overrides_disabled do
+    I18n.overrides_disabled do
       result = Category.exec_sql "SELECT 1 FROM site_settings where name = 'lounge_category_id'"
       if result.count == 0
         description = I18n.t('vip_category_description')

db/migrate/20140122043508_add_meta_category.rb

@@ -2,7 +2,7 @@ class AddMetaCategory < ActiveRecord::Migration
   def up
     return if Rails.env.test?
 
-    I18n.backend.overrides_disabled do
+    I18n.overrides_disabled do
       result = Category.exec_sql "SELECT 1 FROM site_settings where name = 'meta_category_id'"
       if result.count == 0
         description = I18n.t('meta_category_description')

db/migrate/20140227201005_add_staff_category.rb

@@ -2,7 +2,7 @@ class AddStaffCategory < ActiveRecord::Migration
   def up
     return if Rails.env.test?
 
-    I18n.backend.overrides_disabled do
+    I18n.overrides_disabled do
       result = Category.exec_sql "SELECT 1 FROM site_settings where name = 'staff_category_id'"
       if result.count == 0
         description = I18n.t('staff_category_description')

db/migrate/20141014191645_fix_tos_name.rb

@@ -1,6 +1,6 @@
 class FixTosName < ActiveRecord::Migration
   def up
-    I18n.backend.overrides_disabled do
+    I18n.overrides_disabled do
       execute ActiveRecord::Base.sql_fragment('UPDATE user_fields SET name = ? WHERE name = ?', I18n.t('terms_of_service.title'), I18n.t("terms_of_service.signup_form_message"))
     end
 

db/migrate/20150728210202_migrate_old_moderator_posts.rb

@@ -1,7 +1,7 @@
 class MigrateOldModeratorPosts < ActiveRecord::Migration
 
   def migrate_key(action_code)
-    I18n.backend.overrides_disabled do
+    I18n.overrides_disabled do
       text = I18n.t("topic_statuses.#{action_code.gsub('.', '_')}")
 
       execute "UPDATE posts SET action_code = '#{action_code}', raw = '', cooked = '', post_type = 3 where post_type = 2 AND raw = #{ActiveRecord::Base.connection.quote(text)}"

db/migrate/20150729150523_migrate_auto_close_posts.rb

@@ -1,6 +1,6 @@
 class MigrateAutoClosePosts < ActiveRecord::Migration
   def up
-    I18n.backend.overrides_disabled do
+    I18n.overrides_disabled do
       strings = []
       %w(days hours lastpost_days lastpost_hours lastpost_minutes).map do |k|
         strings << I18n.t("topic_statuses.autoclosed_enabled_#{k}.one")

lib/freedom_patches/translate_accelerator.rb

@@ -19,6 +19,10 @@ module I18n
     def reload!
       @loaded_locales = []
       @cache = nil
+
+      @overrides_enabled = true
+      @overrides_by_site = {}
+
       reload_no_cache!
     end
 
@@ -48,18 +52,60 @@ module I18n
       load_locale(locale) unless @loaded_locales.include?(locale)
     end
 
-    def translate(key, *args)
-      load_locale(config.locale) unless @loaded_locales.include?(config.locale)
+    # In some environments such as migrations we don't want to use overrides.
+    # Use this to disable them over a block of ruby code
+    def overrides_disabled
+      @overrides_enabled = false
+      yield
+    ensure
+      @overrides_enabled = true
+    end
+
+    def translate_no_override(key, *args)
       return translate_no_cache(key, *args) if args.length > 0
 
       @cache ||= LruRedux::ThreadSafeCache.new(LRU_CACHE_SIZE)
-      k = "#{key}#{config.locale}#{config.backend.object_id}#{RailsMultisite::ConnectionManagement.current_db}"
+      k = "#{key}#{config.locale}#{config.backend.object_id}"
 
       @cache.getset(k) do
         translate_no_cache(key).freeze
       end
     end
 
+    def translate(key, *args)
+      load_locale(config.locale) unless @loaded_locales.include?(config.locale)
+
+      if @overrides_enabled
+        site = RailsMultisite::ConnectionManagement.current_db
+
+        by_site = @overrides_by_site[site]
+
+        by_locale = nil
+        unless by_site
+          by_site = @overrides_by_site[site] = {}
+
+          # Load overrides
+          TranslationOverride.where(locale: locale).pluck(:translation_key, :value).each do |tuple|
+            by_locale = by_site[locale] ||= {}
+            by_locale[tuple[0]] = tuple[1]
+          end
+        end
+
+        by_locale = by_site[config.locale]
+        if by_locale
+          if args.size > 0 && args[0].is_a?(Hash)
+            args[0][:overrides] = by_locale
+            return backend.translate(config.locale, key, args[0])
+          end
+
+          if result = by_locale[key]
+            return result
+          end
+        end
+      end
+      translate_no_override(key, *args)
+    end
+
     alias_method :t, :translate
   end
 end

lib/i18n/backend/discourse_i18n.rb

@@ -6,10 +6,6 @@ module I18n
       include I18n::Backend::Fallbacks
       include I18n::Backend::Pluralization
 
-      def initialize
-        @overrides_enabled = true
-      end
-
       def available_locales
         # in case you are wondering this is:
         # Dir.glob( File.join(Rails.root, 'config', 'locales', 'client.*.yml') )
@@ -29,22 +25,10 @@ module I18n
         return site_overrides[locale] if site_overrides[locale]
         locale_overrides = site_overrides[locale] = {}
 
-        TranslationOverride.where(locale: locale).pluck(:translation_key, :value).each do |tuple|
-          locale_overrides[tuple[0]] = tuple[1]
-        end
 
         locale_overrides
       end
 
-      # In some environments such as migrations we don't want to use overrides.
-      # Use this to disable them over a block of ruby code
-      def overrides_disabled
-        @overrides_enabled = false
-        yield
-      ensure
-        @overrides_enabled = true
-      end
-
       # force explicit loading
       def load_translations(*filenames)
         unless filenames.empty?
@@ -56,8 +40,22 @@ module I18n
         [locale, SiteSetting.default_locale.to_sym, :en].uniq.compact
       end
 
-      def translate(locale, key, options = {})
-        (@overrides_enabled && overrides_for(locale)[key]) || super(locale, key, options)
+      def lookup(locale, key, scope = [], options = {})
+
+        # Support interpolation and pluralization of overrides
+        if options[:overrides]
+          if options[:count]
+            result = {}
+            options[:overrides].each do |k, v|
+              result[k.split('.').last.to_sym] = v if k != key && k.start_with?(key.to_s)
+            end
+            return result if result.size > 0
+          end
+
+          return options[:overrides][key] if options[:overrides][key]
+        end
+
+        super(locale, key, scope, options)
       end
 
       def exists?(locale, key)

spec/components/discourse_i18n_spec.rb

@@ -7,17 +7,22 @@ describe I18n::Backend::DiscourseI18n do
   let(:backend) { I18n::Backend::DiscourseI18n.new }
 
   before do
-    backend.reload!
-    backend.store_translations(:en, :foo => 'Foo in :en', :bar => 'Bar in :en')
+    I18n.reload!
+    backend.store_translations(:en, :foo => 'Foo in :en', :bar => 'Bar in :en', :wat => "Hello %{count}")
     backend.store_translations(:en, :items => {:one => 'one item', :other => "%{count} items" })
     backend.store_translations(:de, :bar => 'Bar in :de')
     backend.store_translations(:'de-AT', :baz => 'Baz in :de-AT')
   end
 
+  after do
+    I18n.reload!
+  end
+
   it 'translates the basics as expected' do
     expect(backend.translate(:en, 'foo')).to eq("Foo in :en")
     expect(backend.translate(:en, 'items', count: 1)).to eq("one item")
     expect(backend.translate(:en, 'items', count: 3)).to eq("3 items")
+    expect(backend.translate(:en, 'wat', count: 3)).to eq("Hello 3")
   end
 
   describe '#exists?' do
@@ -53,16 +58,38 @@ describe I18n::Backend::DiscourseI18n do
   end
 
   describe 'with overrides' do
-    before do
+    it 'returns the overriden key' do
       TranslationOverride.upsert!('en', 'foo', 'Overwritten foo')
-    end
-
-    it 'returns the overrided key' do
-      expect(backend.translate(:en, 'foo')).to eq('Overwritten foo')
+      expect(I18n.translate('foo')).to eq('Overwritten foo')
 
       TranslationOverride.upsert!('en', 'foo', 'new value')
-      backend.reload!
-      expect(backend.translate(:en, 'foo')).to eq('new value')
+      I18n.reload!
+      expect(I18n.translate('foo')).to eq('new value')
+    end
+
+    it 'supports disabling' do
+      TranslationOverride.upsert!('en', 'foo', 'meep')
+
+      I18n.overrides_disabled do
+        expect(I18n.translate('foo')).to eq('meep')
+      end
+    end
+
+    it 'supports interpolation' do
+      TranslationOverride.upsert!('en', 'foo', 'hello %{world}')
+      expect(I18n.translate('foo', world: 'foo')).to eq('hello foo')
+    end
+
+    it 'supports interpolation named count' do
+      TranslationOverride.upsert!('en', 'wat', 'goodbye %{count}')
+      expect(I18n.translate('wat', count: 123)).to eq('goodbye 123')
+    end
+
+    it 'supports one and other' do
+      TranslationOverride.upsert!('en', 'items.one', 'one fish')
+      TranslationOverride.upsert!('en', 'items.other', '%{count} fishies')
+      expect(I18n.translate('items', count: 13)).to eq('13 fishies')
+      expect(I18n.translate('items', count: 1)).to eq('one fish')
     end
   end