使用npm时遇到Error: Invalid protocol

使用npm安装socket.io时遇到如下错误：

npm ERR! Error: Invalid protocol
npm ERR!     at Request.init (/opt/nodejs/lib/node_modules/npm/node_modules/request/main.js:308:31)
npm ERR!     at new Request (/opt/nodejs/lib/node_modules/npm/node_modules/request/main.js:103:8)
npm ERR!     at request (/opt/nodejs/lib/node_modules/npm/node_modules/request/main.js:962:11)
npm ERR!     at RegClient.makeRequest (/opt/nodejs/lib/node_modules/npm/node_modules/npm-registry-client/lib/request.js:199:13)
npm ERR!     at RegClient.<anonymous> (/opt/nodejs/lib/node_modules/npm/node_modules/npm-registry-client/lib/request.js:116:17)
npm ERR!     at RetryOperation.attempt (/opt/nodejs/lib/node_modules/npm/node_modules/retry/lib/retry_operation.js:56:8)
npm ERR!     at RegClient.regRequest [as request] (/opt/nodejs/lib/node_modules/npm/node_modules/npm-registry-client/lib/request.js:113:13)
npm ERR!     at RegClient.get_ (/opt/nodejs/lib/node_modules/npm/node_modules/npm-registry-client/lib/get.js:112:8)
npm ERR!     at RegClient.<anonymous> (/opt/nodejs/lib/node_modules/npm/node_modules/npm-registry-client/lib/get.js:37:12)
npm ERR!     at fs.readFile (fs.js:176:14)
npm ERR! If you need help, you may report this log at:
npm ERR!     <http://github.com/isaacs/npm/issues>
npm ERR! or email it to:
npm ERR!     <npm-@googlegroups.com>

根据错误提示查看/opt/nodejs/lib/node_modules/npm/node_modules/request/main.js中相关代码：

  var protocol = self.proxy && !self.tunnel ? self.proxy.protocol : self.uri.protocol
    , defaultModules = {'http:':http, 'https:':https}
    , httpModules = self.httpModules || {}
    ;
  self.httpModule = httpModules[protocol] || defaultModules[protocol]
  console.log(protocol);
  console.log(self.proxy);
  console.log(self.tunnel);
  console.log(self.proxy.protocol);
  console.log(self.uri.protocol);
   if (!self.httpModule) throw new Error("Invalid protocol")

其中的console.log为新加入，用于查看到底是哪个参数导致invalid protocol。

结果发现self.proxy解析到错误的值（由于当前server无法访问互联网，在环境中需要设置http_proxy）。

{ protocol: '192.168.1.50:',
  host: '8010',
  hostname: '8010',
  href: '192.168.1.50:8010' }

想到，我在设置http_proxy没有带上协议。后来把http_proxy设置成http://192.168.1.50:8010，不再报错。

Over.

PS：经同事提示，我一直跟大家说http_proxy的设置时，基本都是带有http头的。这次真是自己坑了自己。