默认只支持http代理。
带用户认证的代理：http://username:password@127.0.0.1:1080

设置

npm config set proxy http://127.0.0.1:1080
npm config set https-proxy http://127.0.0.1:1080

查看

npm config get proxy
npm config get https-proxy

清除

npm config delete proxy
npm config delete https-proxy

查看所有自定义设置信息

npm config ls