如何使用Opal生成示例Rails应用程序？

Question

我跟着http://opalrb.org/docs/rails/的导游走。第一步进行得很好：

rails new MyHappyApp --javascript=opal

但当我尝试生成一个脚手架时...

rails g scaffold Persion name age:int
/home/jared/.rvm/gems/ruby-2.1.1@rails32/gems/opal-sprockets-0.0.1/lib/opal/sprockets/server.rb:81: warning: already initialized constant Opal::Server::Index::SOURCE
/home/jared/.rvm/gems/ruby-2.1.1@rails32/gems/opal-0.3.44/lib/opal/server.rb:90: warning: previous definition of SOURCE was here
    SECURITY WARNING: No secret option provided to Rack::Session::Cookie.
    This poses a security threat. It is strongly recommended that you
    provide a secret to prevent exploits that may be possible from crafted
    cookies. This will not be supported in future versions of Rack, and
    future versions will even invalidate your existing user cookies.

    Called from: /home/jared/.rvm/gems/ruby-2.1.1@rails32/gems/actionpack-3.2.0/lib/action_dispatch/middleware/session/abstract_store.rb:28:in `initialize'.
  invoke  active_record
  create    db/migrate/20140613172929_create_persions.rb
  create    app/models/persion.rb
  invoke    test_unit
  create      test/unit/persion_test.rb
  create      test/fixtures/persions.yml
   route  resources :persions
  invoke  scaffold_controller
  create    app/controllers/persions_controller.rb
  invoke    erb
  create      app/views/persions
  create      app/views/persions/index.html.erb
  create      app/views/persions/edit.html.erb
  create      app/views/persions/show.html.erb
  create      app/views/persions/new.html.erb
  create      app/views/persions/_form.html.erb
  invoke    test_unit
  create      test/functional/persions_controller_test.rb
  invoke    helper
  create      app/helpers/persions_helper.rb
  invoke      test_unit
  create        test/unit/helpers/persions_helper_test.rb
  invoke  assets
   error    opal [not found]
  invoke    scss
  create      app/assets/stylesheets/persions.css.scss
  invoke  scss
  create    app/assets/stylesheets/scaffolds.css.scss

有人知道为什么我会看到“找不到蛋白石错误”这句话吗？

Answer 1

我刚刚对此进行了测试，并能够复制错误。

据我所知，opal-rails实际上并没有提供任何资产生成器。遵循Rails约定，在opal-rails/lib/rails/generators/opal/assets或其周围应该有一个assets_generator.rb文件，但在源代码中没有这样的文件。

您可以自己将资产生成器添加到项目中(有关资产生成器的示例，请参阅https://github.com/rails/coffee-rails/blob/master/lib/rails/generators/coffee/assets/assets_generator.rb和相关文件)。

另一种选择是在application.rb文件中设置config.app_generators.javascript_engine = :js，然后适当地将其重命名(例如，重命名为persons.js.rb)。