1 files changed, 61 insertions, 0 deletions
diff --git a/actionpack/lib/sprockets/static_compiler.rb b/actionpack/lib/sprockets/static_compiler.rb
new file mode 100644
index 0000000000..32a9d66e6e
--- /dev/null
+++ b/actionpack/lib/sprockets/static_compiler.rb
@@ -0,0 +1,61 @@
+require 'fileutils'
+
+module Sprockets
+  class StaticCompiler
+    attr_accessor :env, :target, :paths
+
+    def initialize(env, target, paths, options = {})
+      @env = env
+      @target = target
+      @paths = paths
+      @digest = options.key?(:digest) ? options.delete(:digest) : true
+      @manifest = options.key?(:manifest) ? options.delete(:manifest) : true
+      @manifest_path = options.delete(:manifest_path) || target
+    end
+
+    def compile
+      manifest = {}
+      env.each_logical_path do |logical_path|
+        next unless compile_path?(logical_path)
+        if asset = env.find_asset(logical_path)
+          manifest[logical_path] = write_asset(asset)
+        end
+      end
+      write_manifest(manifest) if @manifest
+    end
+
+    def write_manifest(manifest)
+      FileUtils.mkdir_p(@manifest_path)
+      File.open("#{@manifest_path}/manifest.yml", 'wb') do |f|
+        YAML.dump(manifest, f)
+      end
+    end
+
+    def write_asset(asset)
+      path_for(asset).tap do |path|
+        filename = File.join(target, path)
+        FileUtils.mkdir_p File.dirname(filename)
+        asset.write_to(filename)
+        asset.write_to("#{filename}.gz") if filename.to_s =~ /\.(css|js)$/
+      end
+    end
+
+    def compile_path?(logical_path)
+      paths.each do |path|
+        case path
+        when Regexp
+          return true if path.match(logical_path)
+        when Proc
+          return true if path.call(logical_path)
+        else
+          return true if File.fnmatch(path.to_s, logical_path)
+        end
+      end
+      false
+    end
+
+    def path_for(asset)
+      @digest ? asset.digest_path : asset.logical_path
+    end
+  end
+end