rack _escaped_fragment_ handling

SeoAssist.rb

# Make redirects for SEO needs

class SeoAssist
  def initialize(app)
    @app = app
  end

  def call(env)
    request = Rack::Request.new(env)

    if fragment = request.params["_escaped_fragment_"]
      original_fullpath = request.fullpath
      new_uri = uri_from_fragment(request.path, fragment)

      env["PATH_INFO"]    = new_uri.path
      env["QUERY_STRING"] = new_uri.query
      env["REQUEST_URI"]  = request.fullpath

      logger.info "Rack::SeoAssist #{original_fullpath} => #{request.fullpath}"
    end
    @app.call(env)
  end

  private

  def uri_from_fragment(path, fragment)
    path.chop! if path.last == '/'
    URI.parse(path + fragment)
  end

  def logger
    RAILS_DEFAULT_LOGGER || Logger.new(STDOUT)
  end
end