为什么我的开发服务器无法加载？ default_controller_and_action'：缺少：action（ArgumentError）

Question

我是 Ruby nuby（也是 Stack Overflow 的新手），致力于 Michael Hartl 的 Rails 教程 突然我的开发服务器 无法加载并不断退出。控制台也不会加载，并且 Rspec spec/ 产生错误/异常。我包括了终端的一些输出，非常感谢您的帮助。

Exiting
/Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/actionpack-3.0.3/lib/action_dispatch/routing/mapper.rb:164:in `default_controller_and_action': missing :action (ArgumentError)
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/actionpack-3.0.3/lib/action_dispatch/routing/mapper.rb:68:in `normalize_options!'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/actionpack-3.0.3/lib/action_dispatch/routing/mapper.rb:51:in `initialize'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/actionpack-3.0.3/lib/action_dispatch/routing/mapper.rb:261:in `new'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/actionpack-3.0.3/lib/action_dispatch/routing/mapper.rb:261:in `match'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/actionpack-3.0.3/lib/action_dispatch/routing/mapper.rb:1112:in `match'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/actionpack-3.0.3/lib/action_dispatch/routing/mapper.rb:1297:in `match'
    from /Users/ameedachowdhury/rails_projects/railstutorial/config/routes.rb:11:in `block in <top (required)>'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/actionpack-3.0.3/lib/action_dispatch/routing/route_set.rb:233:in `instance_exec'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/actionpack-3.0.3/lib/action_dispatch/routing/route_set.rb:233:in `draw'
    from /Users/ameedachowdhury/rails_projects/railstutorial/config/routes.rb:1:in `<top (required)>'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:235:in `load'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:235:in `block in load'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:225:in `block in load_dependency'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:596:in `new_constants_in'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:225:in `load_dependency'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/activesupport-3.0.3/lib/active_support/dependencies.rb:235:in `load'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/application.rb:127:in `block in reload_routes!'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/application.rb:127:in `each'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/application.rb:127:in `reload_routes!'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/application.rb:120:in `block in routes_reloader'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/activesupport-3.0.3/lib/active_support/file_update_checker.rb:32:in `call'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/activesupport-3.0.3/lib/active_support/file_update_checker.rb:32:in `execute_if_updated'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/application/finisher.rb:51:in `block (2 levels) in <module:Finisher>'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/application/finisher.rb:52:in `call'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/application/finisher.rb:52:in `block in <module:Finisher>'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/initializable.rb:25:in `instance_exec'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/initializable.rb:25:in `run'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/initializable.rb:50:in `block in run_initializers'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/initializable.rb:49:in `each'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/initializable.rb:49:in `run_initializers'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/application.rb:134:in `initialize!'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/application.rb:77:in `method_missing'
    from /Users/ameedachowdhury/rails_projects/railstutorial/config/environment.rb:5:in `<top (required)>'
    from /Users/ameedachowdhury/rails_projects/railstutorial/config.ru:3:in `require'
    from /Users/ameedachowdhury/rails_projects/railstutorial/config.ru:3:in `block in <main>'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/rack-1.2.1/lib/rack/builder.rb:46:in `instance_eval'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/rack-1.2.1/lib/rack/builder.rb:46:in `initialize'
    from /Users/ameedachowdhury/rails_projects/railstutorial/config.ru:1:in `new'
    from /Users/ameedachowdhury/rails_projects/railstutorial/config.ru:1:in `<main>'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/rack-1.2.1/lib/rack/builder.rb:35:in `eval'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/rack-1.2.1/lib/rack/builder.rb:35:in `parse_file'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/rack-1.2.1/lib/rack/server.rb:162:in `app'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/rack-1.2.1/lib/rack/server.rb:248:in `wrapped_app'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/rack-1.2.1/lib/rack/server.rb:213:in `start'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/commands/server.rb:65:in `start'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/commands.rb:30:in `block in <top (required)>'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/commands.rb:27:in `tap'
    from /Users/ameedachowdhury/.rvm/gems/ruby-1.9.2-p0@rails3tutorial/gems/railties-3.0.3/lib/rails/commands.rb:27:in `<top (required)>'
    from script/rails:6:in `require'
    from script/rails:6:in `<main>'
ameeda-chowdhurys-macbook:railstutorial ameedachowdhury$ 

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Answer 1

当我遇到这个问题时，这是因为 routes.rb 中的其中一条路由有斜杠 (/) 而不是哈希 (# >) 使用 controller#action 语法时（我使用了“controller/action”，这是不正确的）。

例如，我不小心有 root :to =>; '主页/索引'。它应该是 root :to =>; 'home#index'。

我在此处找到了这个解决方案。

Answer 2

这是由不正确的路线引起的 -
请检查您的 config/routes.rb ，即使提到的一条路线是错误的，也会引发此错误！！
还要确保路线是

'/url/for/something' => 'controller#action'

或

root :to => 'controller#action

Answer 3

我也是一个 Ruby nuby，在研究 Michael Hartl 的 Rails 教程时也遇到了同样的错误。如果您像我一样，您可能只是在真正阅读或理解文本的情况下输入书中出现的所有代码。并不是所有事情都是一步一步来的。在演示驼峰式大小写与蛇式大小写时，Hartl 显示了一个包含以下代码的框。

$ rails generate controller static_pages ...

此处，Hartl 只是尝试对比使用蛇式大小写生成 StaticPages 控制器的指令，而不是清单 3.4 中完成的驼峰式大小写。点“...”只是为了编辑或截断 cmd 行的其余指令。我准确地输入了显示的内容，并在路线文件中显示以下内容：

SampleApp::Application.routes.draw do
 get "static_pages/..."

 get "static_pages/home"

 get "static_pages/help"

打开您的路线文件，删除

get "static_pages/..."

保存的路线文件，然后尝试再次启动 Rails 服务器。

我还破坏了“rails生成控制器static_pages ...”不确定这是否有任何效果，但现在一切正常。

Answer 4

默认情况下，您会得到以下内容：

Rails.application.routes.draw do
  get 'static_pages/...'

  get 'static_pages/home'

  get 'static_pages/help'

只需删除此内容：

  get 'static_pages/...'

您将在 ROUTES.RB 文件中看到此内容

Rails.application.routes.draw do

  get 'static_pages/home'

  get 'static_pages/help'

Answer 5

就我而言，这是由我的某些路由中的后缀斜杠“/”引起的。例如，

post 'load_query/'

删除此后缀后，

post 'load_query'

它就起作用了。

Answer 6

更改routes.rb 文件中的默认根目录。

get "static_pages#home"  TO root to: 'static_pages#home'

我经历过同样的问题，上述更改对我有用。