Under What Conditions can req.connection.remoteAddress be Blank (ExpressJS)

Question

I have an express app running under Node.js v6.9.4, serving both via HTTP and HTTPS.

I've noticed a few times that requests coming in have had blank remoteAddress data.

Under what conditions can a request have no / blank remoteAddress?

Answer 1

remote address is blank when behind a proxy

https://github.com/hapijs/hapi/issues/1210

you can use

const ip = req.headers['x-forwarded-for'] || (req.connection && req.connection.remoteAddress) || ''

Answer 2

代理

后面的表达

  

虽然如果未设置应用程序变量信任代理，应用程序将无法运行，但除非配置了信任代理，否则它将错误地将代理的IP地址注册为客户端IP地址。

获取IP地址的替代解决方案由@ trushar-gupta

提供

您还可以了解有关 Express代理的更多信息  here