1 files changed, 53 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..fa4f9451df
--- /dev/null
+++ b/actionpack/lib/sprockets/static_compiler.rb
@@ -0,0 +1,53 @@
+require 'fileutils'
+require 'pathname'
+
+module Sprockets
+  class StaticCompiler
+    attr_accessor :env, :target, :digest
+
+    def initialize(env, target, options = {})
+      @env = env
+      @target = target
+      @digest = options.key?(:digest) ? options.delete(:digest) : true
+    end
+
+    def precompile(paths)
+      Rails.application.config.assets.digest = digest
+      manifest = {}
+
+      env.each_logical_path do |logical_path|
+        next unless precompile_path?(logical_path, paths)
+        if asset = env.find_asset(logical_path)
+          manifest[logical_path] = compile(asset)
+        end
+      end
+      manifest
+    end
+
+    def compile(asset)
+      asset_path = digest_asset(asset)
+      filename = target.join(asset_path)
+      FileUtils.mkdir_p filename.dirname
+      asset.write_to(filename)
+      asset.write_to("#{filename}.gz") if filename.to_s =~ /\.(css|js)$/
+      asset_path
+    end
+
+    def precompile_path?(logical_path, paths)
+      paths.each do |path|
+        if path.is_a?(Regexp)
+          return true if path.match(logical_path)
+        elsif path.is_a?(Proc)
+          return true if path.call(logical_path)
+        else
+          return true if File.fnmatch(path.to_s, logical_path)
+        end
+      end
+      false
+    end
+
+    def digest_asset(asset)
+      digest ? asset.digest_path : asset.logical_path
+    end
+  end
+end