update

.dockerignore

@@ -0,0 +1,2 @@
+go.sum
+echo

.gitignore

@@ -1 +1,3 @@
 echo.exe
+nohup.out
+echo

Dockerfile

@@ -0,0 +1,35 @@
+FROM reg.charlienet.top/go/golang:1.22-alpine as builder
+
+ARG app_name=echo
+RUN echo $app_name
+
+ENV APPNAME=echo
+RUN echo $app_name
+
+WORKDIR /build
+
+RUN echo $app_name
+
+COPY . .
+
+ENV GOPROXY https://goproxy.cn,direct
+RUN go mod tidy && go build -ldflags="-s -w"
+
+FROM alpine:3.19
+
+# 使用阿里云镜像
+# RUN sed -i 's/dl-cdn.alpinelinux.org/mirrors.aliyun.com/g' /etc/apk/repositories
+# RUN apk update --no-cache && apk add --no-cache ca-certificates tzdata
+ENV TZ Asia/Shanghai
+
+WORKDIR /app
+COPY --from=builder /build/echo echo
+
+# COPY conf conf
+
+# ENV GIN_MODE=release
+# ENV PATH /app:$PATH
+
+EXPOSE 8080
+
+CMD ["./echo"]

go.mod

@@ -1,3 +1,3 @@
 module echo
 
-go 1.22.4
+go 1.22

main.go

@@ -3,11 +3,16 @@ package main
 import (
 	"fmt"
 	"log"
+	"net"
 	"net/http"
 	"os"
+	"strings"
 )
 
-var name string
+var (
+	name            string
+	RemoteIPHeaders = []string{"X-Forwarded-For", "X-Real-IP"}
+)
 
 func main() {
 	hostname, err := os.Hostname()
@@ -28,9 +33,56 @@ func main() {
 
 func echoHandler(w http.ResponseWriter, r *http.Request) {
 	clientIp := getRemoteIP(r)
-	fmt.Fprintf(w, "hello %s Host %s provides services", clientIp, name)
+
+	log.Printf("client %s connected\n\n", clientIp)
+	fmt.Fprintf(w, "hello %s, Host %s provides services\n", clientIp, name)
 }
 
 func getRemoteIP(r *http.Request) string {
-	return r.RemoteAddr
+	for k, v := range r.Header {
+		fmt.Printf("KEY=%s VALUE=%v\n", k, v)
+	}
+
+	for _, headerName := range RemoteIPHeaders {
+		ip, valid := validateHeader(r.Header.Get(headerName))
+		if valid {
+			return ip
+		}
+	}
+
+	return RemoteIP(r)
+}
+
+func validateHeader(header string) (clientIP string, valid bool) {
+	if header == "" {
+		return "", false
+	}
+	items := strings.Split(header, ",")
+	for i := len(items) - 1; i >= 0; i-- {
+		ipStr := strings.TrimSpace(items[i])
+		ip := net.ParseIP(ipStr)
+		if ip == nil {
+			break
+		}
+
+		if i == 0 {
+			return ipStr, true
+		}
+
+		// // X-Forwarded-For is appended by proxy
+		// // Check IPs in reverse order and stop when find untrusted proxy
+		// if (i == 0) || (!engine.isTrustedProxy(ip)) {
+		// 	return ipStr, true
+		// }
+	}
+	return "", false
+}
+
+func RemoteIP(r *http.Request) string {
+	ip, _, err := net.SplitHostPort(strings.TrimSpace(r.RemoteAddr))
+	if err != nil {
+		return ""
+	}
+
+	return ip
 }