yeoman运行grunt serve 提示错误

今天在使用 yeoman 的时候，当我运行 grunt serve 命令的时候，出现如下提示：

1、Error: Cannot find module 'load-grunt-tasks'

$ grunt serve

Loading "Gruntfile.js" tasks...ERROR
>> Error: Cannot find module 'load-grunt-tasks'
Warning: Task "serve" not found. Use --force to continue.

Aborted due to warnings.

　　该错误是因为没有安装 load-grunt-tasks 插件，我们运行如下命令将，所有该项目依赖的所欲node插件，全部安装，命令如下：

# $ sudo npm install     #for mac
$ npm install

　　该命令会将 package.js 中依赖的所有node插件全部安装。

参考文档：http://stackoverflow.com/questions/18114666/grunt-fatal-error-unable-to-find-local-grunt-in-yeoman

2、Warning: Running "compass:server" (compass) task

$ grunt serve

Running "serve" task

Running "clean:server" (clean) task
>> 0 paths cleaned.

Running "wiredep:app" (wiredep) task

Running "wiredep:test" (wiredep) task

Running "wiredep:sass" (wiredep) task

Running "concurrent:server" (concurrent) task
    Warning: Running "compass:server" (compass) task
    Warning: Command failed: compass --version
    /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/dependency.rb:296:in `to_specs': Could not find 'compass' (>= 0) among 45 total gem(s) (Gem::LoadError)
    	from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/dependency.rb:307:in `to_spec'
    	from /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/lib/ruby/2.0.0/rubygems/core_ext/kernel_gem.rb:47:in `gem'
    	from /usr/bin/compass:22:in `<main>'
     Use --force to continue.

    Aborted due to warnings.

    Execution Time (2015-04-12 05:32:54 UTC)
    loading tasks    5ms  ▇▇▇ 5%
    compass:server  85ms  ▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇ 93%
    Total 91ms Use --force to continue.

        Aborted due to warnings.

Execution Time (2015-04-12 05:32:50 UTC)
wiredep:app        134ms  ▇▇▇ 4%
concurrent:server     3s  ▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇ 95%
Total 3.2s

　　网上搜了一堆blog，最后发现是未安装 compass ，因为我用 yeoman 构建项目的时候，选了使用 sass ，而在yeoman中使用sass则又需要安装 compass （直接使用sass是不需要的）。

参考文档：http://stackoverflow.com/questions/21865609/grunt-need-compass-installed-in-system-path-warning

compass是基于 ruby 的，因此在安装 compass 前，你先需要确定，你的电脑已经安装了 ruby 。

现在我再来安装 compass：

$ gem install compass

　　

安装好 compass 后，在运行 grunt serve 命令，就会自动打开 http://localhost:9000 。

你就会看到 yeoman 构建工具，创建的默认页面。