javascript - "respond_to do |format|"抛出 UnknownFormat 错误

Question

我正在尝试使用 ajax 从 Controller 呈现 js 文件。这个确切的代码以前总是有效，甚至在其他方法中也有效，但我突然开始收到这个错误:

ActionController::UnknownFormat in MoviesController#vote
ActionController::UnknownFormat

电影 Controller :

def vote
  ...
  respond_to do |format| #The error points to this line.
    format.js
  end
end

投票.js.erb:

$('#votes').html("<%= escape_javascript(render 'votes') %>");

链接:

电影.html.erb:

<%= render 'votes' %>

_votes.html.erb

<%= link_to "vote", vote_path, method: :post, remote: true %>

路线.rb:

post 'movies/vote' => 'movies#vote', as: 'vote'

为什么我突然收到这个错误？为什么它在不同的上下文中有效，但在这个上下文中却无效？

使用 Rails 4.0.10

更新:堆栈跟踪

应用程序跟踪:

app/controllers/movies_controller.rb:394:in `vote'

完整跟踪:

actionpack (4.0.10) lib/action_controller/metal/mime_responds.rb:372:in `retrieve_collector_from_mimes'
actionpack (4.0.10) lib/action_controller/metal/mime_responds.rb:189:in `respond_to'
app/controllers/movies_controller.rb:394:in `vote'
actionpack (4.0.10) lib/action_controller/metal/implicit_render.rb:4:in `send_action'
actionpack (4.0.10) lib/abstract_controller/base.rb:189:in `process_action'
actionpack (4.0.10) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (4.0.10) lib/abstract_controller/callbacks.rb:18:in `block in process_action'
activesupport (4.0.10) lib/active_support/callbacks.rb:413:in `_run__1492335060096380544__process_action__callbacks'
activesupport (4.0.10) lib/active_support/callbacks.rb:80:in `run_callbacks'
actionpack (4.0.10) lib/abstract_controller/callbacks.rb:17:in `process_action'
actionpack (4.0.10) lib/action_controller/metal/rescue.rb:29:in `process_action'
actionpack (4.0.10) lib/action_controller/metal/instrumentation.rb:31:in `block in process_action'
activesupport (4.0.10) lib/active_support/notifications.rb:159:in `block in instrument'
activesupport (4.0.10) lib/active_support/notifications/instrumenter.rb:20:in `instrument'
activesupport (4.0.10) lib/active_support/notifications.rb:159:in `instrument'
actionpack (4.0.10) lib/action_controller/metal/instrumentation.rb:30:in `process_action'
actionpack (4.0.10) lib/action_controller/metal/params_wrapper.rb:250:in `process_action'
activerecord (4.0.10) lib/active_record/railties/controller_runtime.rb:18:in `process_action'
actionpack (4.0.10) lib/abstract_controller/base.rb:136:in `process'
actionpack (4.0.10) lib/abstract_controller/rendering.rb:44:in `process'
actionpack (4.0.10) lib/action_controller/metal.rb:195:in `dispatch'
actionpack (4.0.10) lib/action_controller/metal/rack_delegation.rb:13:in `dispatch'
actionpack (4.0.10) lib/action_controller/metal.rb:231:in `block in action'
actionpack (4.0.10) lib/action_dispatch/routing/route_set.rb:82:in `call'
actionpack (4.0.10) lib/action_dispatch/routing/route_set.rb:82:in `dispatch'
actionpack (4.0.10) lib/action_dispatch/routing/route_set.rb:50:in `call'
actionpack (4.0.10) lib/action_dispatch/journey/router.rb:71:in `block in call'
actionpack (4.0.10) lib/action_dispatch/journey/router.rb:59:in `each'
actionpack (4.0.10) lib/action_dispatch/journey/router.rb:59:in `call'
actionpack (4.0.10) lib/action_dispatch/routing/route_set.rb:676:in `call'
warden (1.2.3) lib/warden/manager.rb:35:in `block in call'
warden (1.2.3) lib/warden/manager.rb:34:in `catch'
warden (1.2.3) lib/warden/manager.rb:34:in `call'
rack (1.5.5) lib/rack/etag.rb:23:in `call'
rack (1.5.5) lib/rack/conditionalget.rb:25:in `call'
rack (1.5.5) lib/rack/head.rb:11:in `call'
actionpack (4.0.10) lib/action_dispatch/middleware/params_parser.rb:27:in `call'
actionpack (4.0.10) lib/action_dispatch/middleware/flash.rb:241:in `call'
rack (1.5.5) lib/rack/session/abstract/id.rb:225:in `context'
rack (1.5.5) lib/rack/session/abstract/id.rb:220:in `call'
actionpack (4.0.10) lib/action_dispatch/middleware/cookies.rb:486:in `call'
activerecord (4.0.10) lib/active_record/query_cache.rb:36:in `call'
activerecord (4.0.10) lib/active_record/connection_adapters/abstract/connection_pool.rb:626:in `call'
activerecord (4.0.10) lib/active_record/migration.rb:373:in `call'
actionpack (4.0.10) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
activesupport (4.0.10) lib/active_support/callbacks.rb:373:in `_run__2656547782179467807__call__callbacks'
activesupport (4.0.10) lib/active_support/callbacks.rb:80:in `run_callbacks'
actionpack (4.0.10) lib/action_dispatch/middleware/callbacks.rb:27:in `call'
actionpack (4.0.10) lib/action_dispatch/middleware/reloader.rb:64:in `call'
actionpack (4.0.10) lib/action_dispatch/middleware/remote_ip.rb:76:in `call'
actionpack (4.0.10) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call'
web-console (2.2.1) lib/web_console/middleware.rb:39:in `call'
actionpack (4.0.10) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
railties (4.0.10) lib/rails/rack/logger.rb:38:in `call_app'
railties (4.0.10) lib/rails/rack/logger.rb:20:in `block in call'
activesupport (4.0.10) lib/active_support/tagged_logging.rb:68:in `block in tagged'
activesupport (4.0.10) lib/active_support/tagged_logging.rb:26:in `tagged'
activesupport (4.0.10) lib/active_support/tagged_logging.rb:68:in `tagged'
railties (4.0.10) lib/rails/rack/logger.rb:20:in `call'
actionpack (4.0.10) lib/action_dispatch/middleware/request_id.rb:21:in `call'
rack (1.5.5) lib/rack/methodoverride.rb:21:in `call'
rack (1.5.5) lib/rack/runtime.rb:17:in `call'
activesupport (4.0.10) lib/active_support/cache/strategy/local_cache.rb:83:in `call'
rack (1.5.5) lib/rack/lock.rb:17:in `call'
actionpack (4.0.10) lib/action_dispatch/middleware/static.rb:64:in `call'
rack (1.5.5) lib/rack/sendfile.rb:112:in `call'
railties (4.0.10) lib/rails/engine.rb:511:in `call'
railties (4.0.10) lib/rails/application.rb:97:in `call'
rack (1.5.5) lib/rack/lock.rb:17:in `call'
rack (1.5.5) lib/rack/content_length.rb:14:in `call'
rack (1.5.5) lib/rack/handler/webrick.rb:60:in `service'
/home/greg/.rvm/rubies/ruby-2.0.0-p648/lib/ruby/2.0.0/webrick/httpserver.rb:138:in `service'
/home/greg/.rvm/rubies/ruby-2.0.0-p648/lib/ruby/2.0.0/webrick/httpserver.rb:94:in `run'
/home/greg/.rvm/rubies/ruby-2.0.0-p648/lib/ruby/2.0.0/webrick/server.rb:295:in `block in start_thread'

Answer 1

您可以为路由助手指定 format 选项，以指示链接为 js 而不是默认的 html。像这样指定它:

<%= link_to "vote", vote_path(format: :js), method: :post, remote: true %>

过去，我在使用某些版本的 Rails 时遇到过问题，但我只有关于这方面的轶事证据。我发现在那种情况下确实有效的是:

<%= link_to "vote", "#{vote_path}.js", method: :post, remote: true %>

在第二种情况下，您只需将 .js 扩展名附加到将触发 js 格式的 url 路径。不优雅和蛮力，只能在尝试正确方法失败后使用，但它确实有效。