轨服务器错误，在第一次启动

Question

我在新的轨道，所以我有愚蠢的问题 同时启动轨服务器我有这个错误

rails s 
/var/lib/gems/1.8/gems/execjs-1.4.0/lib/execjs/runtimes.rb:51:in `autodetect': Could not find a JavaScript runtime. See https://github.com/sstephenson/execjs for a list of available runtimes. (ExecJS::RuntimeUnavailable) 
    from /var/lib/gems/1.8/gems/execjs-1.4.0/lib/execjs.rb:5 
    from /var/lib/gems/1.8/gems/coffee-script-2.2.0/lib/coffee_script.rb:1:in `require' 
    from /var/lib/gems/1.8/gems/coffee-script-2.2.0/lib/coffee_script.rb:1 
    from /var/lib/gems/1.8/gems/coffee-script-2.2.0/lib/coffee-script.rb:1:in `require' 
    from /var/lib/gems/1.8/gems/coffee-script-2.2.0/lib/coffee-script.rb:1 
    from /var/lib/gems/1.8/gems/coffee-rails-3.2.2/lib/coffee-rails.rb:1:in `require' 
    from /var/lib/gems/1.8/gems/coffee-rails-3.2.2/lib/coffee-rails.rb:1 
    from /var/lib/gems/1.8/gems/bundler-1.2.3/lib/bundler/runtime.rb:68:in `require' 
    from /var/lib/gems/1.8/gems/bundler-1.2.3/lib/bundler/runtime.rb:68:in `require' 
    from /var/lib/gems/1.8/gems/bundler-1.2.3/lib/bundler/runtime.rb:66:in `each' 
    from /var/lib/gems/1.8/gems/bundler-1.2.3/lib/bundler/runtime.rb:66:in `require' 
    from /var/lib/gems/1.8/gems/bundler-1.2.3/lib/bundler/runtime.rb:55:in `each' 
    from /var/lib/gems/1.8/gems/bundler-1.2.3/lib/bundler/runtime.rb:55:in `require' 
    from /var/lib/gems/1.8/gems/bundler-1.2.3/lib/bundler.rb:128:in `require' 
    from /home/gorysko/rails/rails_project/first_app/config/application.rb:7 
    from /var/lib/gems/1.8/gems/railties-3.2.9/lib/rails/commands.rb:53:in `require' 
    from /var/lib/gems/1.8/gems/railties-3.2.9/lib/rails/commands.rb:53 
    from /var/lib/gems/1.8/gems/railties-3.2.9/lib/rails/commands.rb:50:in `tap' 
    from /var/lib/gems/1.8/gems/railties-3.2.9/lib/rails/commands.rb:50 
    from script/rails:6:in `require' 
    from script/rails:6 

但所有的安装作出在书上和所有的依赖也很好

Answer 1

尝试加入这一行到你的Gemfile

gem 'therubyracer' 

它可以让你从内红宝石评估的JavaScript。你可以查看here。