在新系统上升级到 Rails 3 的 Rails 应用程序不使用 Mongrel

Question

给定：

• Rails 2.3.x 应用程序当前正在升级到 Rails 3。
• 将 ruby​​ 从 1.8.7 升级到 1.9.2
• Rails 应用程序使用 mongrel 作为开发的 Web 服务器。
• 全新安装的 Ubuntu 10.10 Netbook remix。
• 我在开始升级之前忘记安装 mongrel，所以...

问题：

更新一些代码以使延迟作业正常工作后，我去运行 rails s 并且我意识到我正在运行 WEBrick。我为 1.9.2 版本安装 mongrel：gem install mongrel --pre 并再次运行 rails s 。它仍然使用 WEBrick，这不是预期的行为。以前，我只安装 mongrel，rails 就会知道我想要 mongrel。

另外，当 WEBrick 运行时我收到此错误...它启动，然后出错并关闭。 （也许是由于升级或者...也许 WEBrick 不喜欢 ruby​​ 1.9.2？）：

=> Booting WEBrick
=> Rails 3.0.5 application starting in development on http://0.0.0.0:3000
=> Call with -d to detach
=> Ctrl-C to shutdown server
Exiting
/home/aaron/dev/onlinescheduler/config/initializers/new_rails_defaults.rb:14:in `<top (required)>': undefined method `generate_best_match=' for ActionDispatch::Routing:Module (NoMethodError)
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:235:in `load'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:235:in `block in load'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:225:in `block in load_dependency'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:596:in `new_constants_in'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:225:in `load_dependency'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:235:in `load'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/engine.rb:201:in `block (2 levels) in <class:Engine>'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/engine.rb:200:in `each'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/engine.rb:200:in `block in <class:Engine>'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/initializable.rb:25:in `instance_exec'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/initializable.rb:25:in `run'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/initializable.rb:50:in `block in run_initializers'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/initializable.rb:49:in `each'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/initializable.rb:49:in `run_initializers'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/application.rb:134:in `initialize!'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/application.rb:77:in `method_missing'
    from /home/aaron/dev/onlinescheduler/config/environment.rb:5:in `<top (required)>'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:239:in `require'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:239:in `block in require'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:225:in `block in load_dependency'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:596:in `new_constants_in'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:225:in `load_dependency'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/activesupport-3.0.5/lib/active_support/dependencies.rb:239:in `require'
    from /home/aaron/dev/onlinescheduler/config.ru:3:in `block in <main>'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/builder.rb:46:in `instance_eval'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/builder.rb:46:in `initialize'
    from /home/aaron/dev/onlinescheduler/config.ru:1:in `new'
    from /home/aaron/dev/onlinescheduler/config.ru:1:in `<main>'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/builder.rb:35:in `eval'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/builder.rb:35:in `parse_file'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/server.rb:162:in `app'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/server.rb:248:in `wrapped_app'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/rack-1.2.1/lib/rack/server.rb:213:in `start'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/commands/server.rb:65:in `start'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/commands.rb:30:in `block in <top (required)>'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/commands.rb:27:in `tap'
    from /usr/local/rvm/gems/ruby-1.9.2-p180/gems/railties-3.0.5/lib/rails/commands.rb:27:in `<top (required)>'
    from script/rails:6:in `require'
    from script/rails:6:in `<main>'

Answer 1

如果添加会更好

group :development do
  gem :mongrel
end

因为你在生产中不需要它

Answer 2

您需要将gem“mongrel”添加到您的Gemfile中并运行bundle install

Answer 3

请记住，当您将 gem“mongrel”添加到 Gemfile 时，您需要指定：

gem "mongrel", "1.2.0.pre2"

较新版本的 mongrel 与 Rails 3 不兼容。

Answer 4

或者，如果您不想混合，我的理解是您可以注释掉 new_rails_defaults.rb 中的有问题的行。当我这样做时，错误消息就会消失。

Answer 5

尝试使用gem install mongrel --pre

它对我有用！