npm ERR! code CERT_HAS_EXPIRED
npm ERR! errno CERT_HAS_EXPIRED
npm ERR! request to <https://r2.cnpmjs.org/@types/send/-/send-0.17.1.tgz> failed, reason: certificate has expired

# 给 npm 设置不验证证书 
npm config set strict-ssl false

# 或者切换 cnpmjs 网站
# 临时
npm --registry <https://registry.npm.taobao.org> install express
# 长期
npm config set registry <https://registry.npm.taobao.org>

由 npm install 失败引出来的证书问题