ruby-on-rails - Rails : Can't render pages, 获取 JSON 解析错误

Question

我正在开发一个项目，该项目使用 Rails 服务器，同时使用 JSPM 来组织 Javascript 文件，同时还使用 Sprockets 来管道 Assets 。

我的 Rails 服务器可以工作，但我目前无法呈现任何 View 。我认为这与 sprockets 未能成功管理编译 JavaScript 的处理器有关。 (附加说明:JavaScript 是 ES6)。下面的错误似乎是在说服务器试图呈现索引页面，但是 JSON 不存在，因为 JS 没有编译(我的猜测)。这就是说，我真的不知道如何解决这个问题。

错误如下:

`JSON::ParserError in Application#index

Showing /Users/ben/agora/app/views/layouts/application.html.erb where line #14 raised:

A JSON text must at least contain two octets!
  (in /Users/ben/agora/app/assets/javascripts/bundles/application.js.sfx)
Extracted source (around line #14):

11: <%= yield %>
12: 
13: <%= render_react_page %>
14: <%= javascript_include_tag 'bundles/application' %>
15: </body>
16: </html>`

完整的堆栈跟踪如下:

`json (1.8.2) lib/json/common.rb:155:in `initialize'
json (1.8.2) lib/json/common.rb:155:in `new'
json (1.8.2) lib/json/common.rb:155:in `parse'
vendor/gems/jspm-rails/lib/jspm/sfx/template.rb:30:in `block in evaluate'
/Users/ben/.rvm/rubies/ruby-2.2.2/lib/ruby/2.2.0/open3.rb:199:in `popen_run'
/Users/ben/.rvm/rubies/ruby-2.2.2/lib/ruby/2.2.0/open3.rb:93:in `popen3'
vendor/gems/jspm-rails/lib/jspm/sfx/template.rb:24:in `evaluate'
tilt (1.4.1) lib/tilt/template.rb:103:in `render'
sprockets (2.2.3) lib/sprockets/context.rb:193:in `block in evaluate'
sprockets (2.2.3) lib/sprockets/context.rb:190:in `each'
sprockets (2.2.3) lib/sprockets/context.rb:190:in `evaluate'
sprockets (2.2.3) lib/sprockets/processed_asset.rb:12:in `initialize'
sprockets (2.2.3) lib/sprockets/base.rb:249:in `new'
sprockets (2.2.3) lib/sprockets/base.rb:249:in `block in build_asset'
sprockets (2.2.3) lib/sprockets/base.rb:270:in `circular_call_protection'
sprockets (2.2.3) lib/sprockets/base.rb:248:in `build_asset'
sprockets (2.2.3) lib/sprockets/index.rb:93:in `block in build_asset'
sprockets (2.2.3) lib/sprockets/caching.rb:19:in `cache_asset'
sprockets (2.2.3) lib/sprockets/index.rb:92:in `build_asset'
sprockets (2.2.3) lib/sprockets/base.rb:169:in `find_asset'
sprockets (2.2.3) lib/sprockets/index.rb:60:in `find_asset'
sprockets (2.2.3) lib/sprockets/bundled_asset.rb:16:in `initialize'
sprockets (2.2.3) lib/sprockets/base.rb:252:in `new'
sprockets (2.2.3) lib/sprockets/base.rb:252:in `build_asset'
sprockets (2.2.3) lib/sprockets/index.rb:93:in `block in build_asset'
sprockets (2.2.3) lib/sprockets/caching.rb:19:in `cache_asset'
sprockets (2.2.3) lib/sprockets/index.rb:92:in `build_asset'
sprockets (2.2.3) lib/sprockets/base.rb:169:in `find_asset'
sprockets (2.2.3) lib/sprockets/index.rb:60:in `find_asset'
sprockets (2.2.3) lib/sprockets/environment.rb:78:in `find_asset'
sprockets (2.2.3) lib/sprockets/base.rb:177:in `[]'
actionpack (3.2.18) lib/sprockets/helpers/rails_helper.rb:126:in `asset_for'
actionpack (3.2.18) lib/sprockets/helpers/rails_helper.rb:27:in `block in javascript_include_tag'
actionpack (3.2.18) lib/sprockets/helpers/rails_helper.rb:26:in `collect'
actionpack (3.2.18) lib/sprockets/helpers/rails_helper.rb:26:in `javascript_include_tag'
app/views/layouts/application.html.erb:14:in `_app_views_layouts_application_html_erb___4438127222864099562_70202749532280'
actionpack (3.2.18) lib/action_view/template.rb:145:in `block in render'
activesupport (3.2.18) lib/active_support/notifications.rb:125:in `instrument'
actionpack (3.2.18) lib/action_view/template.rb:143:in `render'
actionpack (3.2.18) lib/action_view/renderer/template_renderer.rb:59:in `render_with_layout'
actionpack (3.2.18) lib/action_view/renderer/template_renderer.rb:45:in `render_template'
actionpack (3.2.18) lib/action_view/renderer/template_renderer.rb:18:in `render'
actionpack (3.2.18) lib/action_view/renderer/renderer.rb:36:in `render_template'
actionpack (3.2.18) lib/action_view/renderer/renderer.rb:17:in `render'
actionpack (3.2.18) lib/abstract_controller/rendering.rb:110:in `_render_template'
actionpack (3.2.18) lib/action_controller/metal/streaming.rb:225:in `_render_template'
actionpack (3.2.18) lib/abstract_controller/rendering.rb:103:in `render_to_body'
actionpack (3.2.18) lib/action_controller/metal/renderers.rb:28:in `render_to_body'
actionpack (3.2.18) lib/action_controller/metal/compatibility.rb:50:in `render_to_body'
actionpack (3.2.18) lib/abstract_controller/rendering.rb:88:in `render'
actionpack (3.2.18) lib/action_controller/metal/rendering.rb:16:in `render'
actionpack (3.2.18) lib/action_controller/metal/instrumentation.rb:40:in `block (2 levels) in render'
activesupport (3.2.18) lib/active_support/core_ext/benchmark.rb:5:in `block in ms'
/Users/ben/.rvm/rubies/ruby-2.2.2/lib/ruby/2.2.0/benchmark.rb:303:in `realtime'
activesupport (3.2.18) lib/active_support/core_ext/benchmark.rb:5:in `ms'
actionpack (3.2.18) lib/action_controller/metal/instrumentation.rb:40:in `block in render'
actionpack (3.2.18) lib/action_controller/metal/instrumentation.rb:83:in `cleanup_view_runtime'
sequel-rails (0.9.11) lib/sequel_rails/railties/controller_runtime.rb:24:in `cleanup_view_runtime'
actionpack (3.2.18) lib/action_controller/metal/instrumentation.rb:39:in `render'
app/controllers/application_controller.rb:7:in `index'
actionpack (3.2.18) lib/action_controller/metal/implicit_render.rb:4:in `send_action'
actionpack (3.2.18) lib/abstract_controller/base.rb:167:in `process_action'
actionpack (3.2.18) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (3.2.18) lib/abstract_controller/callbacks.rb:18:in `block in process_action'
activesupport (3.2.18) lib/active_support/callbacks.rb:414:in `_run__749368673318476381__process_action__3475398207843127101__callbacks'
activesupport (3.2.18) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.18) lib/active_support/callbacks.rb:385:in `_run_process_action_callbacks'
activesupport (3.2.18) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.18) lib/abstract_controller/callbacks.rb:17:in `process_action'
actionpack (3.2.18) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (3.2.18) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action'
activesupport (3.2.18) lib/active_support/notifications.rb:123:in `block in instrument'
activesupport (3.2.18) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (3.2.18) lib/active_support/notifications.rb:123:in `instrument'
actionpack (3.2.18) lib/action_controller/metal/instrumentation.rb:29:in `process_action'
actionpack (3.2.18) lib/action_controller/metal/params_wrapper.rb:207:in `process_action'
sequel-rails (0.9.11) lib/sequel_rails/railties/controller_runtime.rb:18:in `process_action'
actionpack (3.2.18) lib/abstract_controller/base.rb:121:in `process'
actionpack (3.2.18) lib/abstract_controller/rendering.rb:45:in `process'
actionpack (3.2.18) lib/action_controller/metal.rb:203:in `dispatch'
actionpack (3.2.18) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
actionpack (3.2.18) lib/action_controller/metal.rb:246:in `block in action'
actionpack (3.2.18) lib/action_dispatch/routing/route_set.rb:73:in `call'
actionpack (3.2.18) lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
actionpack (3.2.18) lib/action_dispatch/routing/route_set.rb:36:in `call'
journey (1.0.4) lib/journey/router.rb:68:in `block in call'
journey (1.0.4) lib/journey/router.rb:56:in `each'
journey (1.0.4) lib/journey/router.rb:56:in `call'
actionpack (3.2.18) lib/action_dispatch/routing/route_set.rb:608:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
rack (1.4.5) lib/rack/etag.rb:23:in `call'
rack (1.4.5) lib/rack/conditionalget.rb:25:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/head.rb:14:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/params_parser.rb:21:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/flash.rb:242:in `call'
rack (1.4.5) lib/rack/session/abstract/id.rb:210:in `context'
rack (1.4.5) lib/rack/session/abstract/id.rb:205:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/cookies.rb:341:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/callbacks.rb:28:in `block in call'
activesupport (3.2.18) lib/active_support/callbacks.rb:405:in `_run__103614042811221451__call__1909597293413008327__callbacks'
activesupport (3.2.18) lib/active_support/callbacks.rb:405:in `__run_callback'
activesupport (3.2.18) lib/active_support/callbacks.rb:385:in `_run_call_callbacks'
activesupport (3.2.18) lib/active_support/callbacks.rb:81:in `run_callbacks'
actionpack (3.2.18) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/reloader.rb:65:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/remote_ip.rb:31:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/debug_exceptions.rb:16:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/show_exceptions.rb:56:in `call'
railties (3.2.18) lib/rails/rack/logger.rb:32:in `call_app'
railties (3.2.18) lib/rails/rack/logger.rb:16:in `block in call'
activesupport (3.2.18) lib/active_support/tagged_logging.rb:22:in `tagged'
railties (3.2.18) lib/rails/rack/logger.rb:16:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/request_id.rb:22:in `call'
rack (1.4.5) lib/rack/methodoverride.rb:21:in `call'
rack (1.4.5) lib/rack/runtime.rb:17:in `call'
activesupport (3.2.18) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
rack (1.4.5) lib/rack/lock.rb:15:in `call'
actionpack (3.2.18) lib/action_dispatch/middleware/static.rb:63:in `call'
railties (3.2.18) lib/rails/engine.rb:484:in `call'
railties (3.2.18) lib/rails/application.rb:231:in `call'
rack (1.4.5) lib/rack/content_length.rb:14:in `call'
railties (3.2.18) lib/rails/rack/log_tailer.rb:17:in `call'
thin (1.6.3) lib/thin/connection.rb:86:in `block in pre_process'
thin (1.6.3) lib/thin/connection.rb:84:in `catch'
thin (1.6.3) lib/thin/connection.rb:84:in `pre_process'
thin (1.6.3) lib/thin/connection.rb:53:in `process'
thin (1.6.3) lib/thin/connection.rb:39:in `receive_data'
eventmachine (1.0.7) lib/eventmachine.rb:187:in `run_machine'
eventmachine (1.0.7) lib/eventmachine.rb:187:in `run'
thin (1.6.3) lib/thin/backends/base.rb:73:in `start'
thin (1.6.3) lib/thin/server.rb:162:in `start'
rack (1.4.5) lib/rack/handler/thin.rb:13:in `run'
rack (1.4.5) lib/rack/server.rb:268:in `start'
railties (3.2.18) lib/rails/commands/server.rb:70:in `start'
railties (3.2.18) lib/rails/commands.rb:55:in `block in <top (required)>'
railties (3.2.18) lib/rails/commands.rb:50:in `tap'
railties (3.2.18) lib/rails/commands.rb:50:in `<top (required)>'
script/rails:6:in `require'
script/rails:6:in `<main>'`

Answer 1

为此需要查看 gemfile。猜测是您缺少 JS 运行时，这导致 JS 未被编译，从而导致缺少 JSON。

查看:Rails 3.1 issue with javascript_include_tag in application.html.erb (来自@Confusion 的回答)