Replaced the Controller with a piece of Metal:

* removed controller
* removed routing
* added a Metal/Rack middleware to handle the requests instead
* updated README

Many thanks to Daniel Neighman (hassox) for his help converting this to Rack at RailsCamp in Melbourne!

README.rdoc

@@ -25,12 +25,12 @@ PluginAssets takes these "view paths" and builds the same thing for "public path
 
 Given a request for "/stylesheets/foo/bah.css", the web server would first look for "bah.css" in "RAILS_ROOT/public/foo/bah.css".  If that resource doesn't exist, the request would usually be passed through to Rails, which will try to route the request to a controller action and eventually respond with a 404 (file not found).
 
-Instead, this plugin sets up a controller and appropriate routing to handle the request, searching for the file in your plugins and gem plugins.  In this case, it would search for "bah.css" in the following locations:
+Instead, this plugin intercepts the requests for these missing assets with a piece of middleware, searching through the installed plugins.  In this case, it would search for "bah.css" in the following locations:
 
 * RAILS_ROOT/vendor/plugins/plugin_123/public/stylesheets/foo/bah.css
 * RAILS_ROOT/vendor/plugins/plugin_456/public/stylesheets/foo/bah.css
 
-As soon as a matching file is found, it's passed back to the browser with the correct mime type.  If none of the plugins have such a file, the regular Rails 404 response for a missing template is invoked.
+As soon as a matching file is found, it's passed back to the browser with the correct mime type.  If none of the plugins have such a file, the request is passed onto Rails, which will handle the 404 like it usually does.
 
 It works for plugins and gem plugins. It works for the following URLs:
 
@@ -43,7 +43,7 @@ One day I'll make it configurable for other assets, but in the meantime it's eas
 
 ==Caveats
 
-PluginAssets leverages the view_paths array used by Rails plugins that supply their own views.  Rails plugins and gems are only added to the view_paths array automatically if there's an app/views directory inside the plugin.  If you're supplying public assets, chances are pretty good you're supplying views too, so that probably isn't a big deal.
+Publicious leverages the view_paths array used by Rails plugins that supply their own views.  Rails plugins and gems are only added to the view_paths array automatically if there's an app/views directory inside the plugin.  If you're supplying public assets, chances are pretty good you're supplying views too, so that probably isn't a big deal.
 
 
 ==Isn't it inefficient?
@@ -58,11 +58,10 @@ I wrote this on the train this morning as a proof of concept, so there's a long
 * It should be a gem plugin, so that other gem plugins can list it as a dependency
 * I haven't written any tests
 * I haven't tackled caching yet (probably need to do both page caching and header response caching)
-* Thinking this could be Rack middleware or Rails Metal rather than a full Rails request stack.
 
 I actually want to see this in Rails core, so help me make it awesome!
 
 
 ==Etc
 
-Publicious is Copyright (c) 2009 Justin French, released under the MIT license.  Your feedback, forkings and contributions are greatly welcomed.
+Publicious is Copyright (c) 2009 Justin French, released under the MIT license.  Your feedback, forkings and contributions are greatly welcomed.  Many thanks to Daniel Neighman (hassox) for his help converting Publicious to Rack middleware rather than a regular Rails routing and controller stack.

app/metal/publicious_metal.rb

@@ -0,0 +1,49 @@
+class PubliciousMetal
+
+  def self.call(env)
+    request = Rack::Request.new(env)
+    if request.path_info =~  %r{^\/(#{allowed_dirs.join("|")})}
+      file_name = nil
+      path = nil
+
+      public_paths.detect do |pub_path|
+        path = pub_path
+        fp   = File.join(pub_path, request.path_info)
+        file_name = fp if File.file?(fp)
+      end
+
+      return respond_not_found! unless file_name
+
+      # Make sure pricks aren't ../../config/database.yml ing us
+      respond_not_found! unless file_name.gsub(%r[^#{path}], "") == request.path_info
+
+      Rack::Response.new(
+        File.open(file_name),
+        200,'Content-Type' => content_type_for_file(file_name)
+      ).finish
+    else
+      respond_not_found!
+    end
+  end
+
+  def self.respond_not_found!
+    Rack::Response.new("Not Found", 404).finish
+  end
+
+  def self.allowed_dirs
+    %w(stylesheets javascripts images)
+  end
+
+  def self.content_type_for_file(name)
+    file_name = File.basename(name).split(".").last.to_s
+    Mime::Type.lookup_by_extension(file_name).to_s
+  end
+
+  def self.public_paths
+    ActionController::Base.view_paths.map do |vp|
+      full_path = File.expand_path(vp.to_s, RAILS_ROOT)
+      full_path.sub("app/views", "public") if full_path =~ /vendor/
+    end.compact
+  end
+
+end

rails/init.rb

@@ -0,0 +1,3 @@
+Mime::Type.register "image/jpeg", :jpg
+Mime::Type.register "image/gif", :gif
+Mime::Type.register "image/png", :png

test/multiple_match_test.rb

@@ -0,0 +1,54 @@
+require File.dirname(__FILE__) + '/test_helper'
+
+class MultipleMatchesTest < Test::Unit::TestCase
+
+  include TestHelper
+
+  def setup
+    super
+
+    setup_plugin :no_file_here
+    setup_plugin :my_plugin
+    setup_plugin :your_plugin
+
+    @path           = 'foo/bah.css'
+
+    @filename_1     = "/tmp/vendor/my_plugin/public/stylesheets/#{@path}"
+    @filecontents_1 = "hello from my stylesheet"
+    FileUtils.mkdir(File.dirname(@filename_1))
+    File.open(@filename_1, 'w') do |file|
+      file << @filecontents_1
+    end
+
+    @filename_2     = "/tmp/vendor/your_plugin/public/stylesheets/#{@path}"
+    @filecontents_2 = "hello from your stylesheet"
+    FileUtils.mkdir(File.dirname(@filename_2))
+    File.open(@filename_2, 'w') do |file|
+      file << @filecontents_2
+    end
+
+    get "/stylesheets/#{@path}"
+  end
+
+  def test_should_respond_with_success
+    assert last_response.ok?
+  end
+
+  def test_view_paths_should_contain_three_items
+    assert_equal 4, ActionController::Base.view_paths.size
+  end
+
+  def test_public_paths_should_contain_two_items
+    assert_equal 3, app.public_paths.size # one less that view_paths
+  end
+
+  def test_public_paths_should_contain_the_plugins_public_dir
+    assert_equal "/tmp/vendor/my_plugin/public", app.public_paths.second
+  end
+
+  def test_should_respond_with_first_file_contents
+    assert_equal File.read(@filename_1), last_response.body
+    assert_equal @filecontents_1, last_response.body
+  end
+
+end

test/no_match_test.rb

@@ -0,0 +1,12 @@
+require File.join(File.dirname(__FILE__), "test_helper")
+
+class NoMatchTest < Test::Unit::TestCase
+
+  include TestHelper
+
+  def test_redirect_logged_in_users_to_dashboard
+    get "/stylesheets/not_here.css"
+    assert last_response.not_found?
+  end
+
+end

test/single_match_test.rb

@@ -1,37 +1,44 @@
-require File.dirname(__FILE__) + '/test_helper'
-
-class SingleMatchTest < PubliciousBaseTest
+require File.join(File.dirname(__FILE__), "test_helper")
 
+class SingleMatchTest < Test::Unit::TestCase
+
+  include TestHelper
+
   def setup
     super
+
     setup_plugin :my_plugin
 
-    @path           = ['foo', 'bah.css']
-    @filename       = "/tmp/vendor/my_plugin/public/stylesheets/#{@path.join('/')}"
+    @path           = 'foo/bah.css'
+    @filename       = "/tmp/vendor/my_plugin/public/stylesheets/#{@path}"
     @filecontents   = "hello from stylesheet"
     FileUtils.mkdir(File.dirname(@filename))
     File.open(@filename, 'w') do |file|
       file << "hello from stylesheet"
     end
 
-    get :show, :path => @path
+    get "/stylesheets/#{@path}"
   end
 
-  test "view_paths should contain two items" do
-    assert_equal 2, @controller.view_paths.size
+  def test_should_respond_with_success
+    assert last_response.ok?
   end
 
-  test "public_paths should contain one item (one less than view paths)" do
-    assert_equal 1, @controller.send(:public_paths).size
+  def test_view_paths_should_contain_three_items
+    assert_equal 2, ActionController::Base.view_paths.size
   end
 
-  test "public_paths should contain the plugin's public dir" do
-    assert_equal "/tmp/vendor/my_plugin/public", @controller.send(:public_paths).first
+  def test_public_paths_should_contain_two_items
+    assert_equal 1, app.public_paths.size # one less that view_paths
+  end
+
+  def test_public_paths_should_contain_the_plugins_public_dir
+    assert_equal "/tmp/vendor/my_plugin/public", app.public_paths.first
   end
 
-  test "should respond with the file contents" do
-    assert_equal File.read(@filename), @controller.response.body
-    assert_equal @filecontents, @controller.response.body
+  def test_should_respond_with_first_file_contents
+    assert_equal File.read(@filename), last_response.body
+    assert_equal @filecontents, last_response.body
   end
 
-end
+end