test

Author: Andrea Cambieri

.idea/.gitignore

@@ -0,0 +1,3 @@
+module continuity
+
+go 1.24

go.mod

@@ -0,0 +1,77 @@
+package server
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"net"
+	"strings"
+)
+
+func main() {
+	listener, err := net.Listen("tcp", ":8080")
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+	for {
+		conn, err := listener.Accept()
+		if err != nil {
+			go handleConnection(conn)
+		}
+	}
+}
+
+func handleConnection(conn net.Conn) {
+	r := bufio.NewReader(conn)
+	defer conn.Close()
+	headers := make(map[string]string)
+	//read until \n\n
+	for {
+		line, err := r.ReadString('\n')
+		if (len(line) == 2) || err != nil {
+			break
+		}
+		tokens := strings.Split(line, ":")
+		if len(tokens) < 2 {
+			continue
+		}
+		headers[tokens[0]] = strings.TrimSpace(tokens[1])
+	}
+	upstream := "8081"
+	if headers["x-client-version"] == "1" {
+		upstream = "8082"
+	} else if headers["x-client-version"] == "2" {
+		upstream = "8083"
+	}
+
+	upstreamConn, err := net.Dial("tcp", "localhost:"+upstream)
+	if err != nil {
+		fmt.Printf("Error connecting to upstream: %s\n", err)
+		return
+	}
+	defer upstreamConn.Close()
+	for key, value := range headers {
+		_, err := fmt.Fprintf(upstreamConn, "%s: %s\n", key, value)
+		if err != nil {
+			fmt.Printf("Error writing to upstream: %s\n", err)
+			return
+		}
+	}
+	_, err = fmt.Fprintf(upstreamConn, "\r\n")
+	if err != nil {
+		fmt.Printf("Error writing to upstream: %s\n", err)
+		return
+	}
+	_, err = io.Copy(upstreamConn, conn)
+	if err != nil {
+		fmt.Printf("Error writing to upstream: %s\n", err)
+		return
+	}
+	_, err = io.Copy(conn, upstreamConn)
+	if err != nil {
+		fmt.Printf("Error writing response from upstream: %s\n", err)
+		return
+	}
+
+}