Shifter for YUI module packaging integrated in Rails

jammit.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name      = 'jammit'
-  s.version   = '0.6.6'         # Keep version in sync with jammit.rb
+  s.version   = '0.6.6clic'         # Keep version in sync with jammit.rb
   s.date      = '2013-03-20'
 
   s.homepage    = "http://documentcloud.github.com/jammit/"

lib/jammit.rb

@@ -4,7 +4,7 @@
 # to all of the configuration options.
 module Jammit
 
-  VERSION                       = "0.6.6"
+  VERSION                       = "0.6.6clic"
 
   ROOT                          = File.expand_path(File.dirname(__FILE__) + '/..')
 
@@ -26,6 +26,10 @@ module Jammit
 
   DEFAULT_JAVASCRIPT_COMPRESSOR = :jsmin
 
+  JAVASCRIPT_BUILDERS           = [:shifter]
+
+  DEFAULT_JAVASCRIPT_BUILDER    = :shifter
+
   CSS_COMPRESSORS               = [:cssmin, :yui, :sass]
 
   DEFAULT_CSS_COMPRESSOR        = :cssmin
@@ -52,13 +56,13 @@ class DeprecationError < StandardError; end
 
   class << self
     attr_reader   :configuration, :template_function, :template_namespace,
-                  :embed_assets, :package_assets, :compress_assets, :gzip_assets,
-                  :package_path, :mhtml_enabled, :include_jst_script, :config_path,
-                  :javascript_compressor, :compressor_options, :css_compressor,
+                  :embed_assets, :package_assets, :compress_assets, :build_assets, :gzip_assets,
+                  :files_changed, :package_path, :mhtml_enabled, :include_jst_script, :config_path,
+                  :javascript_compressor, :javascript_builder, :compressor_options, :css_compressor,
                   :css_compressor_options, :template_extension,
                   :template_extension_matcher, :allow_debugging,
                   :rewrite_relative_paths, :public_root
-    attr_accessor :javascript_compressors, :css_compressors
+    attr_accessor :javascript_compressors, :javascript_builders, :css_compressors
   end
 
   # The minimal required configuration.
@@ -67,6 +71,7 @@ class << self
   @package_path   = DEFAULT_PACKAGE_PATH
 
   @javascript_compressors = JAVASCRIPT_COMPRESSORS
+  @javascript_builders    = JAVASCRIPT_BUILDERS
   @css_compressors        = CSS_COMPRESSORS
 
   # Load the complete asset configuration from the specified @config_path@.
@@ -86,13 +91,16 @@ def self.load_configuration(config_path, soft=false)
     @package_path           = conf[:package_path] || DEFAULT_PACKAGE_PATH
     @embed_assets           = conf[:embed_assets] || conf[:embed_images]
     @compress_assets        = !(conf[:compress_assets] == false)
+    @build_assets           = !(conf[:build_assets] == false)
     @rewrite_relative_paths = !(conf[:rewrite_relative_paths] == false)
     @gzip_assets            = !(conf[:gzip_assets] == false)
     @allow_debugging        = !(conf[:allow_debugging] == false)
     @mhtml_enabled          = @embed_assets && @embed_assets != "datauri"
     @compressor_options     = symbolize_keys(conf[:compressor_options] || {})
     @css_compressor_options = symbolize_keys(conf[:css_compressor_options] || {})
+    @files_changed     = list_git_changes
     set_javascript_compressor(conf[:javascript_compressor])
+    set_javascript_builder(conf[:javascript_builder])
     set_css_compressor(conf[:css_compressor])
     set_package_assets(conf[:package_assets])
     set_template_function(conf[:template_function])
@@ -146,6 +154,18 @@ def self.package!(options={})
     packager.precache_all(options[:output_folder], options[:base_url])
   end
 
+  # Lists the files that were changed
+  def self.list_git_changes
+    list = []
+    if `git --version` =~ /[\d\.]+/
+      list = `git ls-files -m`.split(/\r?\n/)
+      list = list.map{ |f|  Pathname.new(f).absolute? ? f : File.join(ASSET_ROOT, f) }
+    else
+      Jammit.warn('Please check that Git is installed and available in your PATH')
+    end
+    list
+  end
+
   private
 
   # Allows command-line definition of `PUBLIC_ROOT`, for those using Jammit
@@ -160,6 +180,12 @@ def self.set_javascript_compressor(value)
     @javascript_compressor = javascript_compressors.include?(value) ? value : DEFAULT_JAVASCRIPT_COMPRESSOR
   end
 
+  # Ensure that the JavaScript builder is a valid choice.
+  def self.set_javascript_builder(value)
+    value = value && value.to_sym
+    @javascript_builder = javascript_builders.include?(value) ? value : DEFAULT_JAVASCRIPT_BUILDER
+  end
+
   # Ensure that the CSS compressor is a valid choice.
   def self.set_css_compressor(value)
     value = value && value.to_sym
@@ -203,13 +229,27 @@ def self.check_java_version
     @checked_java_version = true
   end
 
+  def self.check_shifter
+    return true if @checked_shifter_version
+    version = (`shifter -v 2>&1`)
+    disable_build if !version
+    @checked_shifter_version = true
+  end
+
   # If we don't have a working Java VM, then disable asset compression and
   # complain loudly.
   def self.disable_compression
     @compress_assets = false
     warn("Asset compression disabled -- Java unavailable.")
   end
 
+  # If we don't have a working Shifter, then disable YUI module build and
+  # complain loudly.
+  def self.disable_build
+    @build_assets = false
+    warn("Asset build disabled -- Shifter unavailable.")
+  end
+
   # Jammit 0.5+ no longer supports separate template packages.
   def self.check_for_deprecations
     if @configuration[:templates]

lib/jammit/builder.rb

@@ -0,0 +1,36 @@
+
+module Jammit
+  # A builder needs
+  # - to expose a 'do_it' method to build the given files
+  # - to expose a 'build_file_2_src_dir' method to get the src folder form the build file
+  class Builder
+
+    JAVASCRIPT_BUILDERS = {
+      :shifter    => Jammit.javascript_builders.include?(:shifter)  ? Jammit::ShifterBuilder : nil
+    }
+
+    def initialize
+      if Jammit.javascript_builders.include?(:shifter)
+        Jammit.check_shifter
+      end
+      js_flavor       = Jammit.javascript_builder || Jammit::DEFAULT_JAVASCRIPT_BUILDER
+      @js_builder     = JAVASCRIPT_BUILDERS[js_flavor].new
+    end
+
+    # YUI Shifter to build JS modules
+    def build_js(paths)
+      paths = [paths] unless paths.is_a? Array
+      if Jammit.build_assets
+        @js_builder.do_it(paths)
+      end
+    end
+
+    # Check if src file has changed
+    def changed?(glob)
+      src_dir = @js_builder.build_file_2_src_dir glob
+      Jammit.files_changed.any? { |js| js.include? src_dir }
+    end
+
+  end
+
+end

lib/jammit/dependencies.rb

@@ -46,6 +46,8 @@
 require 'cssmin'
 require 'jammit/jsmin_compressor'
 require 'jammit/cssmin_compressor'
+require 'jammit/shifter_builder'
+require 'jammit/builder'
 require 'jammit/compressor'
 require 'jammit/packager'
 

lib/jammit/packager.rb

@@ -74,6 +74,10 @@ def compressor
       @compressor ||= Compressor.new
     end
 
+    def builder
+      @builder ||= Builder.new
+    end
+
     # Return the compressed contents of a stylesheet package.
     def pack_stylesheets(package, variant=nil, asset_url=nil)
       compressor.compress_css(package_for(package, :css)[:paths], variant, asset_url)
@@ -103,8 +107,16 @@ def package_for(package, extension)
     # Print a warning if no files were found that match the glob.
     def glob_files(glob)
       absolute = Pathname.new(glob).absolute?
-      paths = Dir[absolute ? glob : File.join(ASSET_ROOT, glob)].sort
-      Jammit.warn("No assets match '#{glob}'") if paths.empty?
+      glob_f = absolute ? glob : File.join(ASSET_ROOT, glob)
+      paths = Dir[glob_f].sort
+      # For a javascript asset which doesnt contain a '*' wildcard
+      if glob =~ /\/[^*^\/]+\.js$/ and (paths.empty? or builder.changed?(glob_f))
+          Jammit.warn("File '#{glob_f}' missing") if paths.empty?
+          Jammit.warn("File '#{glob_f}' changed") if builder.changed?(glob_f)
+          builder.build_js(glob_f)
+      else
+        Jammit.warn("No assets match '#{glob}'") if paths.empty?
+      end
       paths
     end
 

lib/jammit/shifter_builder.rb

@@ -0,0 +1,27 @@
+class Jammit::ShifterBuilder
+
+  def do_it(js)
+    js.map { |p| build_file_2_src_dir p}.each { |j| shift(j) }
+  end
+
+  # Get the dir name to src/
+  def build_file_2_src_dir(glob)
+    build_root = glob[/(.*)\/build\/(.*)/,1]
+    build_root+'/src/' if build_root
+  end
+
+  private
+
+  def shift(glob)
+    # Try to shift it
+    src_dir = glob
+    Jammit.warn("Trying to shift #{src_dir}")
+    FileUtils.cd(src_dir) do
+      Dir.glob('*').select {|f| File.directory? f}.each do |mod|
+        FileUtils.cd(mod) do
+          `shifter`
+        end
+      end
+    end
+  end
+end

test/config/assets-build.yml

@@ -0,0 +1,12 @@
+javascript_compressor: yui
+css_compressor: yui
+embed_assets: on
+compress_assets: true
+build_assets: true
+javascript_builder: shifter
+
+javascripts:
+  workspace:
+    - fixtures/src/test1.js
+    - fixtures/src/test2.js
+    - fixtures/build/test3/test3.js  # Missing asset to try to build

test/fixtures/src/test3/build.json

@@ -0,0 +1,10 @@
+{
+    "name": "test3",
+    "builds": {
+        "test3": {
+            "jsfiles": [
+                "test3.js"
+            ]
+        }
+    }
+}

test/fixtures/src/test3/js/test3.js

@@ -0,0 +1,5 @@
+var mandelay = {
+  name : function() { return this.constructor.prototype; }
+};
+
+myself.sayHi(mandelay.name());

test/unit/test_builder.rb

@@ -0,0 +1,20 @@
+require 'test_helper'
+
+class BuilderTest < Test::Unit::TestCase
+
+  def setup
+    Jammit.load_configuration('test/config/assets-build.yml')
+    @packager = Jammit.packager
+    @builder = Builder.new
+  end
+
+  def teardown
+    FileUtils.rm_rf 'test/fixtures/build/'
+  end
+
+  def test_javascript_build
+    build_file = 'test/fixtures/build/test3/test3.js'
+    assert File.exists?(build_file), "Expected #{build_file} to be generated"
+  end
+
+end