Ruby on Rails：无法加载rack / handler /

Posted 2021-04-15

昨晚我有一个完全工作的Rails服务器。但是，在今天早上访问我的电脑时，我发现它已经崩溃了。我启动了备份，然后SSH连接到我的远程服务器，并尝试重新启动服务器进程，首先查询：

rails server -h

结果导致：

/usr/local/lib/site_ruby/2.3.0/rubygems.rb:270:in `find_spec_for_exe': can't find gem railties (>= 0.a) (Gem::GemNotFoundException)
from /usr/local/lib/site_ruby/2.3.0/rubygems.rb:298:in `activate_bin_path'
from /usr/local/bin/rails:22:in `<main>'

然后我尝试了一个bundle install，它抛出了以下错误：

    enter code here/usr/local/lib/site_ruby/2.3.0/rubygems.rb:270:in `find_spec_for_exe': can't find gem bundler (>= 0.a) (Gem::GemNotFoundException)
from /usr/local/lib/site_ruby/2.3.0/rubygems.rb:298:in `activate_bin_path'
from /usr/local/bin/bundle:22:in `<main>'

然后我用rvm use ruby-2.3.1@rails5.0 --create和gem install rails重新安装了Rails。 rails -v现在报道：

Rails 5.0.1

但是，当我尝试启动服务器进程（rails server -p 80 - b 139.162.246.138）时，我得到：

Exiting
/home/peter/.rvm/gems/ruby-2.3.1@rails5.0/gems/rack-2.0.1/lib/rack/handler.rb:74:in `require': cannot load such file -- rack/handler/- (LoadError)
    from /home/peter/.rvm/gems/ruby-2.3.1@rails5.0/gems/rack-2.0.1/lib/rack/handler.rb:74:in `try_require'
    from /home/peter/.rvm/gems/ruby-2.3.1@rails5.0/gems/rack-2.0.1/lib/rack/handler.rb:16:in `get'
    from /home/peter/.rvm/gems/ruby-2.3.1@rails5.0/gems/rack-2.0.1/lib/rack/server.rb:300:in `server'
    from /home/peter/.rvm/gems/ruby-2.3.1@rails5.0/gems/railties-5.0.1/lib/rails/commands/server.rb:112:in `print_boot_information'
    from /home/peter/.rvm/gems/ruby-2.3.1@rails5.0/gems/railties-5.0.1/lib/rails/commands/server.rb:73:in `start'
    from /home/peter/.rvm/gems/ruby-2.3.1@rails5.0/gems/railties-5.0.1/lib/rails/commands/commands_tasks.rb:90:in `block in server'
    from /home/peter/.rvm/gems/ruby-2.3.1@rails5.0/gems/railties-5.0.1/lib/rails/commands/commands_tasks.rb:85:in `tap'
    from /home/peter/.rvm/gems/ruby-2.3.1@rails5.0/gems/railties-5.0.1/lib/rails/commands/commands_tasks.rb:85:in `server'
    from /home/peter/.rvm/gems/ruby-2.3.1@rails5.0/gems/railties-5.0.1/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
    from /home/peter/.rvm/gems/ruby-2.3.1@rails5.0/gems/railties-5.0.1/lib/rails/commands.rb:18:in `<top (required)>'
    from bin/rails:4:in `require'
    from bin/rails:4:in `<main>'

我尝试卸载并重新安装ruby和rails，并运行新的bundle install。没有得到基本相同的错误：

    /home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/activesupport-5.0.1/lib/active_support/xml_mini.rb:51: warning: constant ::Fixnum is deprecated
/home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/activesupport-5.0.1/lib/active_support/xml_mini.rb:52: warning: constant ::Bignum is deprecated
Exiting
/home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/rack-2.0.1/lib/rack/handler.rb:74:in `require': cannot load such file -- rack/handler/- (LoadError)
    from /home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/rack-2.0.1/lib/rack/handler.rb:74:in `try_require'
    from /home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/rack-2.0.1/lib/rack/handler.rb:16:in `get'
    from /home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/rack-2.0.1/lib/rack/server.rb:300:in `server'
    from /home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/railties-5.0.1/lib/rails/commands/server.rb:112:in `print_boot_information'
    from /home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/railties-5.0.1/lib/rails/commands/server.rb:73:in `start'
    from /home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/railties-5.0.1/lib/rails/commands/commands_tasks.rb:90:in `block in server'
    from /home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/railties-5.0.1/lib/rails/commands/commands_tasks.rb:85:in `tap'
    from /home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/railties-5.0.1/lib/rails/commands/commands_tasks.rb:85:in `server'
    from /home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/railties-5.0.1/lib/rails/commands/commands_tasks.rb:49:in `run_command!'
    from /home/peter/.rvm/gems/ruby-2.4.0-rc1/gems/railties-5.0.1/lib/rails/commands.rb:18:in `<top (required)>'
    from bin/rails:4:in `require'
    from bin/rails:4:in `<main>'

我还尝试完全卸载rails和railties：

gem uninstall rails -v 5.0.1
gem uninstall railties -v 5.0.1
gem install rails -v 5.0.1
gen install railties -v 5.0.1

同样的错误。

尝试使用以下命令查找问题：

sudo grep -rnw './' -e "/var/lib/gems/2.3.0/"

从源目录输出到控制台。

尝试访问错误消息中列出的目录会导致：

cd /var/lib/gems/
-bash: /home/peter/.rvm/scripts/initialize: No such file or directory 
-bash: /home/peter/.rvm/scripts/hook: No such file or directory

运行sudo gem uninstall --all以删除所有宝石会导致：

You have requested to uninstall the gem:
    actioncable-5.0.1

rails-5.0.1 depends on actioncable (= 5.0.1)
If you remove this gem, these dependencies will not be met.
Continue with Uninstall? [yN]  ERROR:  While executing gem ... (Gem::DependencyRemovalException)
    Uninstallation aborted due to dependent gem(s)

虽然在运行命令之前删除rails-5.0.1 gem修复了这个...但是，在运行这个应该删除所有gem的命令之后，rails -v现在输出：

Rails 4.2.7.1

并运行gem uninstall rails-4.2.7.1不会删除此版本。

gem uninstall -v rails-4.2.7.1导致：

ERROR:  While executing gem ... (Gem::Requirement::BadRequirementError)
Illformed requirement ["rails-4.2.7.1"]

更新：最终设法删除rails和ruby。重新安装它们。同样的问题。

尝试创建一个重新启动项目和新项目完全相同的事情。

答案

完成所有工作后，解决方案很简单。我在打字：

rails server -p 80 - b 139.162.246.138

代替：

rails server -p 80 -b 139.162.246.138

另一答案

你使用=> rbenv安装宝石后重新开始吗？如果没有检查=> gemfile以确保你有匹配的ruby版本以及你的=> gemfile.lock（在你工作的目录中）

另一答案

这个故事的寓意是，如果你在调用rails服务器时在命令行上乱码，你会得到：

bootsnap-1.3.2/lib/bootsnap/load_path_cache/
core_ext/kernel_require.rb:32:in `require': cannot 
load such file -- rack/handler/--some-wrong-option (LoadError)  

这有点模棱两可。这不是bootsnap无法加载机架，它是无法加载机架“一些错误的选项”处理程序，因为你的选项是错误的，可能是一个错字。