yarn install 是报错

Arguments:
/usr/local/bin/node /usr/local/bin/yarn install

PATH:
/Users/mac/.composer/vendor/bin:/Users/mac/bin:/usr/local/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Users/mac/.composer/vendor/bin

Yarn version:
0.17.10

Node version:
7.4.0

Platform:
darwin x64

npm manifest:
{

“private”: true,
“devDependencies”: {
  “gulp”: “^3.8.8”
},
“dependencies”: {
  “laravel-elixir”: “^4.0.0”,
  “bootstrap-sass”: “^3.0.0”
}

}

yarn manifest:
No manifest

cuo

Lockfile:
No lockfile

Trace:
Error: read ETIMEDOUT

  at exports._errnoException (util.js:1022:11)
  at TLSWrap.onread (net.js:572:26)</p>

这个是yarn_error.log 文件，请问我要怎么弄，在网上找不半天都没有什么结果