由于 ExecJS 在生产服务器上运行 Rake 任务失败

Question

我在 RHEL 6 机器上安装了 Rails 4 应用程序。

生产使用Passenger和Apache2。

最近我一直在尝试使用 When Gem 和 Cron 将 Rake 任务作为计划作业集成到生产中。

每当我尝试在生产环境中运行这些 Rake 任务之一时，都会收到以下错误：

rake aborted!
ExecJS::RuntimeUnavailable: Could not find a JavaScript runtime. See https://github.com/sstephenson/execjs for a list of available runtimes.

重要的是要提到机器上安装了 NodeJS。我可以预编译资产，等等。 具体来说，命令node --version 产生：v0.10.31

这是我的堆栈跟踪：

  rake aborted!
    ExecJS::RuntimeUnavailable: Could not find a JavaScript runtime. See https://github.com/sstephenson/execjs for a list of available runtimes.
    /var/www/eng_performance/shared/bundle/ruby/2.0.0/gems/execjs-2.2.1/lib/execjs/runtimes.rb:51:in `autodetect'
    /var/www/eng_performance/shared/bundle/ruby/2.0.0/gems/execjs-2.2.1/lib/execjs.rb:5:in `<module:ExecJS>'
    /var/www/eng_performance/shared/bundle/ruby/2.0.0/gems/execjs-2.2.1/lib/execjs.rb:4:in `<top (required)>'
    /var/www/eng_performance/shared/bundle/ruby/2.0.0/gems/activesupport-4.0.4/lib/active_support/dependencies.rb:229:in `require'
    /var/www/eng_performance/shared/bundle/ruby/2.0.0/gems/activesupport-4.0.4/lib/active_support/dependencies.rb:229:in `block in require'
    /var/www/eng_performance/shared/bundle/ruby/2.0.0/gems/activesupport-4.0.4/lib/active_support/dependencies.rb:214:in `load_dependency'
    /var/www/eng_performance/shared/bundle/ruby/2.0.0/gems/activesupport-4.0.4/lib/active_support/dependencies.rb:229:in `require'
    /var/www/eng_performance/shared/bundle/ruby/2.0.0/gems/uglifier-2.5.3/lib/uglifier.rb:3:in `<top (required)>'
    /home/deploy/.rvm/gems/ruby-2.0.0-p481/gems/bundler-1.7.2/lib/bundler/runtime.rb:76:in `require'
    /home/deploy/.rvm/gems/ruby-2.0.0-p481/gems/bundler-1.7.2/lib/bundler/runtime.rb:76:in `block (2 levels) in require'
    /home/deploy/.rvm/gems/ruby-2.0.0-p481/gems/bundler-1.7.2/lib/bundler/runtime.rb:72:in `each'
    /home/deploy/.rvm/gems/ruby-2.0.0-p481/gems/bundler-1.7.2/lib/bundler/runtime.rb:72:in `block in require'
    /home/deploy/.rvm/gems/ruby-2.0.0-p481/gems/bundler-1.7.2/lib/bundler/runtime.rb:61:in `each'
    /home/deploy/.rvm/gems/ruby-2.0.0-p481/gems/bundler-1.7.2/lib/bundler/runtime.rb:61:in `require'
    /home/deploy/.rvm/gems/ruby-2.0.0-p481/gems/bundler-1.7.2/lib/bundler.rb:133:in `require'
    /var/www/eng_performance/releases/20141014084554/config/application.rb:7:in `<top (required)>'
    /var/www/eng_performance/releases/20141014084554/Rakefile:4:in `require'
    /var/www/eng_performance/releases/20141014084554/Rakefile:4:in `<top (required)>'
    (See full trace by running task with --trace)

注意： 我已经从源代码编译安装了 NodeJS，因为当我尝试从 repo 安装时，我遇到了这个我不知道如何克服的错误：

Packages skipped because of dependency problems:
    c-ares19-1.9.1-5.el6.3.x86_64 from epel
    http-parser-2.0-4.20121128gitcd01361.el6.x86_64 from epel
    1:libuv-0.10.28-1.el6.x86_64 from epel
    nodejs-0.10.30-1.el6.x86_64 from epel
    1:v8-3.14.5.10-11.el6.x86_64 from epel

Answer 1

好吧，终于，我能够解决这个问题了:)

事实证明，node.js 的安装并没有什么问题，而是引用了它。

我不知道为什么一开始就改变了，但是following this post 解决了这个问题——即通过添加符号链接ln -s /usr/local/bin/node /usr/bin/node。

注意：我很确定符号链接不是最佳做法。如果有人可以提出另一个想法 - 我很乐意听到它..

希望这是我在使用 node.js 时遇到的最后一个错误。 如果发生类似这样的其他错误，rubyracer 将提供出色的备份解决方案。