Go语言中获取IP地址的方法小结

package main
 
import (
	"fmt"
	"net"
)
 
func main() {
	// 获取所有网络接口
	interfaces, err := net.Interfaces()
	if err != nil {
		fmt.Println("Error:", err)
		return
	}
 
	// 遍历所有网络接口
	for _, iface := range interfaces {
		// 排除一些特殊接口
		if iface.Flags&net.FlagUp == 0 || iface.Flags&net.FlagLoopback != 0 {
			continue
		}
 
		// 获取接口的地址信息
		addrs, err := iface.Addrs()
		if err != nil {
			fmt.Println("Error:", err)
			continue
		}
 
		// 遍历接口的地址
		for _, addr := range addrs {
			// 检查地址类型
			switch v := addr.(type) {
			case *net.IPNet:
				// IPv4 或 IPv6 地址
				fmt.Println(v.IP)
			case *net.IPAddr:
				// 一般情况下是 IPv4 地址
				fmt.Println(v.IP)
			}
		}
	}
}

type Request struct {
    ...
    // RemoteAddr allows HTTP servers and other software to record
	// the network address that sent the request, usually for
	// logging. This field is not filled in by ReadRequest and
	// has no defined format. The HTTP server in this package
	// sets RemoteAddr to an "IP:port" address before invoking a
	// handler.
	// This field is ignored by the HTTP client.
	RemoteAddr string
    ...
}

package main
 
import (
	"fmt"
	"net/http"
)
 
func main() {
	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		// 通过 RemoteAddr 获取客户端的 IP 地址和端口号
		ip, _, err := net.SplitHostPort(r.RemoteAddr)
		if err != nil {
			fmt.Println("Error extracting IP:", err)
			return
		}
 
		fmt.Fprintf(w, "Client IP: %s", ip)
	})
 
	// 启动 HTTP 服务器，监听在 8080 端口
	http.ListenAndServe(":8080", nil)
}

// ClientIP implements one best effort algorithm to return the real client IP. 
// It calls c.RemoteIP() under the hood, to check if the remote IP is a trusted proxy or not. 
// If it is it will then try to parse the headers defined in Engine.RemoteIPHeaders (defaulting to [X-Forwarded-For, X-Real-Ip]). 
// If the headers are not syntactically valid OR the remote IP does not correspond to a trusted proxy, the remote IP (coming from Request.RemoteAddr) is returned.
func (c *Context) ClientIP() string

package main
 
import (
	"github.com/gin-gonic/gin"
	"net/http"
)
 
func main() {
	r := gin.Default()
 
	r.GET("/", func(c *gin.Context) {
		// 获取客户端的 IP 地址
		clientIP := c.ClientIP()
 
		c.String(http.StatusOK, "Client IP: %s", clientIP)
	})
 
	// 启动 Gin 服务器，监听在 8080 端口
	r.Run(":8080")
}