rails new <app> 或 rails -h 无法加载此类文件 -- io/console

Question

[ec2-user@ip-XX-XXX-XXX-XXX rails]$ rails -h
/usr/share/ruby/vendor_ruby/2.0/rubygems/core_ext/kernel_require.rb:55:in `require': cannot load such file -- io/console (LoadError)
    from /usr/share/ruby/vendor_ruby/2.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /usr/local/share/ruby/gems/2.0/gems/thor-0.19.1/lib/thor/shell/basic.rb:2:in `<top (required)>'
    from /usr/share/ruby/vendor_ruby/2.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /usr/share/ruby/vendor_ruby/2.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /usr/local/share/ruby/gems/2.0/gems/thor-0.19.1/lib/thor/shell/color.rb:1:in `<top (required)>'
    from /usr/local/share/ruby/gems/2.0/gems/thor-0.19.1/lib/thor/shell.rb:17:in `shell'
    from /usr/local/share/ruby/gems/2.0/gems/thor-0.19.1/lib/thor/base.rb:439:in `start'
    from /usr/local/share/ruby/gems/2.0/gems/railties-4.1.0/lib/rails/commands/application.rb:17:in `<top (required)>'
    from /usr/share/ruby/vendor_ruby/2.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /usr/share/ruby/vendor_ruby/2.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /usr/local/share/ruby/gems/2.0/gems/railties-4.1.0/lib/rails/cli.rb:14:in `<top (required)>'
    from /usr/share/ruby/vendor_ruby/2.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /usr/share/ruby/vendor_ruby/2.0/rubygems/core_ext/kernel_require.rb:55:in `require'
    from /usr/local/share/ruby/gems/2.0/gems/railties-4.1.0/bin/rails:9:in `<top (required)>'
    from /usr/local/bin/rails:23:in `load'
    from /usr/local/bin/rails:23:in `<main>'

我确实使用 $ gem install rails 安装了 Ruby on Rails，它也很好地完成了。我用 $echo $? 检查了进程状态0 表示成功。

有趣的是，这两个命令可以正常工作：

$ which rails
/usr/local/bin/rails

$ rails -v
Rails 4.1.0

这是一个 64 位的 Amazon Web Services AMI 映像。请帮我解决这个问题。

我已经安装了捆绑器：

$ gem install bundler
Fetching: bundler-1.6.2.gem (100%)
Successfully installed bundler-1.6.2
Parsing documentation for bundler-1.6.2
Installing ri documentation for bundler-1.6.2
Done installing documentation for bundler after 5 seconds
1 gem installed

我检查了重复安装：

$ find / 2>/dev/null| grep bin/ruby
/usr/bin/ruby
/usr/bin/ruby2.0

$ find / 2>/dev/null| grep bin/rails
/usr/local/share/ruby/gems/2.0/gems/railties-4.1.0/bin/rails
/usr/local/share/ruby/gems/2.0/gems/railties-4.1.0/lib/rails/generators/rails/plugin/templates/bin/rails.tt
/usr/local/share/ruby/gems/2.0/gems/railties-4.1.0/lib/rails/generators/rails/app/templates/bin/rails
/usr/local/share/ruby/gems/2.0/gems/rails-4.1.0/guides/code/getting_started/bin/rails
/usr/local/bin/rails
/home/ec2-user/.gem/ruby/2.0/gems/rails-4.1.0/guides/code/getting_started/bin/rails

Answer 1

您需要安装io-console gem。使用以下命令安装它：

gem install io-console

运行后rails -h

另外，运行echo $PATH 并确保路径中有/usr/local/bin。如果没有，那么您需要添加它。

Answer 2

所以我在同一天晚上解决了这个问题，但不知何故 Stackoverflow 没有向我发送任何关于问题回复的通知，所以我不知道这些回复。这就是我最终做的。它本质上是移除 ruby​​ on rails 安装并从头开始安装。这是在 Amazon Web 服务服务器上 - linux 风格。

sudo yum update

$wget  https://raw.github.com/wayneeseguin/rvm/master/binscripts/rvm-installer

$ bash -s stable < rvm-installer

$ source /home/ec2-user/.rvm/scripts/rvm

$ rvm requirements

$ sudo yum erase ruby

$ rvm install ruby

$ rvm use ruby --default

$ rvm rubygems current

$ gem install rails   # this takes forever

之后就正常了。

Answer 3

我在 AWS Elastic Beanstalk（Puma、Ruby 2、Rails 4.0）上遇到了完全相同的问题：

> rails generate simple_form:install --bootstrap

/usr/local/share/ruby/gems/2.0/gems/activesupport-4.0.0/lib/active_support/dependencies.rb:228:in `require': cannot load such file -- io/console (LoadError)

我只是补充了一句：

gem 'io-console'

到我的 Gemfile 顶部并在盒子上再次运行 bundle install 以获得巨大成功。希望比为遇到此问题的其他人重新安装导轨更快。

Answer 4

谢谢；你确实需要 io-console。要使其工作，请安装 GCC。稍后需要休息，所以：

yum -y install gcc mysql-devel ImageMagick-devel

那么，

gem install io-console

工作，我可以继续安装。