Рельсы ошибка сервера на убунту

Question

Я следую рубин на рельсах руководство по началу работы (http://guides.rubyonrails.org/getting_started.html) я установил рубин и рельсы, как это предлагается в руководстве, но когда я пытаюсь выполнить:

bin/rails server 

я вижу следующее сообщение об ошибке в терминале:

Warning: Running `gem pristine --all` to regenerate your installed gemspecs (and deleting then reinstalling your bundle if you use bundle --path) will improve the startup performance of Spring. 
/var/lib/gems/2.1.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:80:in `rescue in block (2 levels) in require': There was an error while trying to load the gem 'uglifier'. (Bundler::GemRequireError) 
from /var/lib/gems/2.1.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:76:in `block (2 levels) in require' 
from /var/lib/gems/2.1.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:72:in `each' 
from /var/lib/gems/2.1.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:72:in `block in require' 
from /var/lib/gems/2.1.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:61:in `each' 
from /var/lib/gems/2.1.0/gems/bundler-1.11.2/lib/bundler/runtime.rb:61:in `require' 
from /var/lib/gems/2.1.0/gems/bundler-1.11.2/lib/bundler.rb:99:in `require' 
from /home/soroosh/rails/blog/config/application.rb:7:in `<top (required)>' 
from /var/lib/gems/2.1.0/gems/railties-4.2.5.1/lib/rails/commands/commands_tasks.rb:78:in `require' 
from /var/lib/gems/2.1.0/gems/railties-4.2.5.1/lib/rails/commands/commands_tasks.rb:78:in `block in server' 
from /var/lib/gems/2.1.0/gems/railties-4.2.5.1/lib/rails/commands/commands_tasks.rb:75:in `tap' 
from /var/lib/gems/2.1.0/gems/railties-4.2.5.1/lib/rails/commands/commands_tasks.rb:75:in `server' 
from /var/lib/gems/2.1.0/gems/railties-4.2.5.1/lib/rails/commands/commands_tasks.rb:39:in `run_command!' 
from /var/lib/gems/2.1.0/gems/railties-4.2.5.1/lib/rails/commands.rb:17:in `<top (required)>' 
from /home/soroosh/rails/blog/bin/rails:9:in `require' 
from /home/soroosh/rails/blog/bin/rails:9:in `<top (required)>' 
from /var/lib/gems/2.1.0/gems/spring-1.6.3/lib/spring/client/rails.rb:28:in `load' 
from /var/lib/gems/2.1.0/gems/spring-1.6.3/lib/spring/client/rails.rb:28:in `call' 
from /var/lib/gems/2.1.0/gems/spring-1.6.3/lib/spring/client/command.rb:7:in `call' 
from /var/lib/gems/2.1.0/gems/spring-1.6.3/lib/spring/client.rb:28:in `run' 
from /var/lib/gems/2.1.0/gems/spring-1.6.3/bin/spring:49:in `<top (required)>' 
from /var/lib/gems/2.1.0/gems/spring-1.6.3/lib/spring/binstub.rb:11:in `load' 
from /var/lib/gems/2.1.0/gems/spring-1.6.3/lib/spring/binstub.rb:11:in `<top (required)>' 
from /usr/lib/ruby/2.1.0/rubygems/core_ext/kernel_require.rb:55:in `require' 
from /usr/lib/ruby/2.1.0/rubygems/core_ext/kernel_require.rb:55:in `require' 
from /home/soroosh/rails/blog/bin/spring:13:in `<top (required)>' 
from bin/rails:3:in `load' 
from bin/rails:3:in `<main>' 

Я использую Ubuntu 15.10, рубин 2.1 и rails4.2.5.1

Answer 1

Если вы внимательно посмотрите на сообщение об ошибке, это важная строка:

There was an error while trying to load the gem 'uglifier'. 

Uglifier обертка Javascript, поэтому он будет нужен переводчик Javascript. Я рекомендую при установке NodeJS:

sudo apt-get install nodejs 

подробнее о uglifier: https://github.com/lautis/uglifier