如何获取客户端的 IP 地址

¥How to get the IP address of the client

直接连接​

¥Direct connection

客户端的 IP 地址可以在 handshake 对象中找到：

¥The IP address of the client can be found in the handshake object:

io.on("connection", (socket) => {
  const ipAddress = socket.handshake.address;

  console.log(ipAddress); // prints something like "203.0.113.195" (IPv4) or "2001:db8:85a3:8d3:1319:8a2e:370:7348" (IPv6)
});

在代理后面​

¥Behind a proxy

如果你使用像 nginx 这样的代理，则 address 属性将是代理的 IP 地址。

¥If you are behind a proxy like nginx, the address attribute will be the IP address of the proxy.

在这种情况下，客户端的 IP 地址将在请求标头中找到。

¥In that case, the IP address of the client will be found in the request headers.

X-Forwarded-For 标头​

¥X-Forwarded-For header

X-Forwarded-For 请求标头是事实上的标准标头，用于识别通过代理服务器连接到 Web 服务器的客户端的原始 IP 地址。

¥The X-Forwarded-For request header was a de-facto standard header for identifying the originating IP address of a client connecting to a web server through a proxy server.

参考：https://web.nodejs.cn/en-US/docs/Web/HTTP/Headers/X-Forwarded-For

¥Reference: https://web.nodejs.cn/en-US/docs/Web/HTTP/Headers/X-Forwarded-For

格式：

¥Format:

X-Forwarded-For: <client>, <proxy1>, <proxy2>

以下是检索客户端 IP 地址的方法：

¥Here's how you can retrieve the IP address of the client:

io.on("connection", (socket) => {
  const ipAddress = socket.handshake.headers["x-forwarded-for"].split(",")[0];

  console.log(ipAddress);
});

Forwarded 标头​

¥Forwarded header

Forwarded 请求标头是用于识别通过代理服务器连接到 Web 服务器的客户端的原始 IP 地址的标准标头。

¥The Forwarded request header is the standard header for identifying the originating IP address of a client connecting to a web server through a proxy server.

参考：https://web.nodejs.cn/en-US/docs/Web/HTTP/Headers/Forwarded

¥Reference: https://web.nodejs.cn/en-US/docs/Web/HTTP/Headers/Forwarded

格式：

¥Format:

Forwarded: by=<identifier>;for=<identifier>;host=<host>;proto=http|https

以下是检索客户端 IP 地址的方法：

¥Here's how you can retrieve the IP address of the client:

function parseHeader(header) {
  for (const directive of header.split(",")[0].split(";")) {
    if (directive.startsWith("for=")) {
      return directive.substring(4);
    }
  }
}

io.on("connection", (socket) => {
  const ipAddress = parseHeader(socket.handshake.headers["forwarded"] || "");

  console.log(ipAddress);
});

CloudFlare​

CloudFlare 使用特定标头：cf-connecting-ip

¥CloudFlare uses a specific header: cf-connecting-ip

参考：https://developers.cloudflare.com/fundamentals/reference/http-request-headers/

¥Reference: https://developers.cloudflare.com/fundamentals/reference/http-request-headers/

以下是检索客户端 IP 地址的方法：

¥Here's how you can retrieve the IP address of the client:

io.on("connection", (socket) => {
  const ipAddress = socket.handshake.headers["cf-connecting-ip"];

  console.log(ipAddress);
});

快速​

¥Fastly

快速使用特定标头：fastly-client-ip

¥Fastly uses a specific header: fastly-client-ip

参考：https://developer.fastly.com/reference/http/http-headers/Fastly-Client-IP/

¥Reference: https://developer.fastly.com/reference/http/http-headers/Fastly-Client-IP/

以下是检索客户端 IP 地址的方法：

¥Here's how you can retrieve the IP address of the client:

io.on("connection", (socket) => {
  const ipAddress = socket.handshake.headers["fastly-client-ip"];

  console.log(ipAddress);
});