Added middleware that automatically exports translations with caching…

… support.

README.rdoc

@@ -44,7 +44,13 @@ Examples:
   - file: 'public/javascripts/path-to-your-second-file.js'
     only: ['*.activerecord', '*.admin.*.title']
 
-If <tt>only</tt> is omitted all the translations will be saved
+If <tt>only</tt> is omitted all the translations will be saved. Also, make sure you add that initial <tt>*</tt>; it specifies that all languages will be exported. If you want to export only one language, you can do something like this:
+
+  translations:
+  - file: 'public/javascripts/en.js'
+    only: 'en.*'
+  - file: 'public/javascripts/pt-BR.js'
+    only: 'pt-BR.*'
 
 To find more examples on how to use the configuration file please refer to the tests.
 

config/i18n-js.yml

@@ -1,6 +1,3 @@
-# Find more details about this configuration file
-# at http://github.com/fnando/i18n-js
-
 # Split context in several files.
 # By default only one file with all translations is exported and
 # no configuration is required. Your settings for asset pipeline

lib/i18n-js.rb

@@ -6,6 +6,7 @@ module I18n
 
     require "i18n-js/railtie" if Rails.version >= "3.0"
     require "i18n-js/engine" if Rails.version >= "3.1"
+    require "i18n-js/middleware"
 
     # deep_merge by Stefan Rusterholz, see http://www.ruby-forum.com/topic/142809
     MERGER = proc { |key, v1, v2| Hash === v1 && Hash === v2 ? v1.merge(v2, &MERGER) : v2 }
@@ -15,7 +16,7 @@ def config_file
     end
 
     def export_dir
-      if Rails.version >= "3.1" && Rails.application.config.assets.enabled
+      if Rails.version >= "3.1" && Rails.configuration.assets.enabled
         "app/assets/javascripts/i18n"
       else
         "public/javascripts"
@@ -49,17 +50,12 @@ def export!
     # custom output directory
     def config
       if config?
-        YAML.load_file(config_file).with_indifferent_access
+        (YAML.load_file(config_file) || {}).with_indifferent_access
       else
         {}
       end
     end
 
-    # Check if translations can be automatically exported.
-    def auto_export?
-      Rails.env.development? || (config? && config[:auto_export])
-    end
-
     # Check if configuration file exist
     def config?
       File.file? config_file

lib/i18n-js/middleware.rb

@@ -0,0 +1,52 @@
+module SimplesIdeias
+  module I18n
+    class Middleware
+      def initialize(app)
+        @app = app
+      end
+
+      def call(env)
+        @cache = nil
+        verify_locale_files!
+        @app.call(env)
+      end
+
+      private
+      def cache_path
+        @cache_path ||= Rails.root.join("tmp/cache/i18n-js.yml")
+      end
+
+      def cache
+        @cache ||= begin
+          if cache_path.exist?
+            YAML.load_file(cache_path) || {}
+          else
+            {}
+          end
+        end
+      end
+
+      def verify_locale_files!
+        valid_cache = []
+        changed_files = []
+
+        valid_cache.push cache_path.exist?
+        valid_cache.push ::I18n.load_path.size == cache.size
+
+        ::I18n.load_path.each do |path|
+          change = File.mtime(path).to_i
+          file_has_changed = change != cache[path]
+          valid_cache.push file_has_changed
+          changed_files << path if file_has_changed
+          cache[path] = change
+        end
+
+        File.open(cache_path, "w+") do |file|
+          file << cache.to_yaml
+        end
+
+        SimplesIdeias::I18n.export! unless valid_cache.all?
+      end
+    end
+  end
+end

lib/i18n-js/railtie.rb

@@ -5,10 +5,8 @@ class Railtie < Rails::Railtie
         require "i18n-js/rake"
       end
 
-      config.to_prepare do
-        SimplesIdeias::I18n.tap do |i18n|
-          i18n.export! if i18n.auto_export?
-        end
+      initializer "i18n-js.initialize" do |app|
+        app.config.middleware.use(Middleware) if Rails.env.development?
       end
     end
   end

spec/i18n_spec.rb

@@ -50,6 +50,7 @@
   end
 
   it "loads configuration file" do
+    set_config "default.yml"
     SimplesIdeias::I18n.setup!
 
     SimplesIdeias::I18n.config?.should be_true
@@ -67,12 +68,6 @@
     Rails.root.join(SimplesIdeias::I18n.export_dir, "translations.js").should be_file
   end
 
-  it "exports messages using the default configuration file" do
-    set_config "default.yml"
-    SimplesIdeias::I18n.should_receive(:save).with(translations, "public/javascripts/translations.js")
-    SimplesIdeias::I18n.export!
-  end
-
   it "exports messages using custom output path" do
     set_config "custom_path.yml"
     SimplesIdeias::I18n.should_receive(:save).with(translations, "public/javascripts/translations/all.js")
@@ -159,34 +154,16 @@
     File.read(SimplesIdeias::I18n.javascript_file).should == "UPDATED"
   end
 
-  describe "#auto_export?" do
-    it "returns true for development mode" do
-      Rails.env = stub(:development? => true)
-      SimplesIdeias::I18n.should be_auto_export
-    end
-
-    it "returns false for production mode" do
-      Rails.env = stub(:production? => true, :development? => false)
-      SimplesIdeias::I18n.should_not be_auto_export
-    end
-
-    it "returns true for production when configuration is set" do
-      Rails.env = stub(:production? => true, :development? => false)
-      SimplesIdeias::I18n.stub :config? => true, :config => {:auto_export => true}
-      SimplesIdeias::I18n.should be_auto_export
-    end
-  end
-
   describe "#export_dir" do
     it "detects Rails 3.1 with asset pipeline enabled" do
       Rails.version = "3.1"
-      Rails.stub_chain(:application, :config, :assets, :enabled => true)
+      Rails.stub_chain(:configuration, :assets, :enabled => true)
       SimplesIdeias::I18n.export_dir == "vendor/assets/javascripts"
     end
 
     it "detects Rails 3.1 with asset pipeline disabled" do
       Rails.version = "3.1"
-      Rails.stub_chain(:application, :config, :assets, :enabled => false)
+      Rails.stub_chain(:configuration, :assets, :enabled => false)
       SimplesIdeias::I18n.export_dir == "public/javascripts"
     end
 
@@ -200,8 +177,8 @@
   # Set the configuration as the current one
   def set_config(path)
     config = HashWithIndifferentAccess.new(YAML.load_file(File.dirname(__FILE__) + "/resources/#{path}"))
-    SimplesIdeias::I18n.should_receive(:config?).and_return(true)
-    SimplesIdeias::I18n.should_receive(:config).and_return(config)
+    SimplesIdeias::I18n.stub(:config? => true)
+    SimplesIdeias::I18n.stub(:config => config)
   end
 
   # Shortcut to SimplesIdeias::I18n.translations