#17 add outline of the TCP proxy

cmd/tcpproxy/main.go

@@ -0,0 +1,5 @@
+package main
+
+func main() {
+
+}

internal/proxy/tcp.go

@@ -0,0 +1,72 @@
+package proxy
+
+import (
+	"fmt"
+	"net"
+)
+
+type Sender interface {
+	Accept() error
+}
+
+// TCPReceiver is responsible for the reading
+// incoming tcp connections
+type TCPReceiver struct {
+	localAddr string // localAddr is an address of the proxy server
+}
+
+func NewTCPReceiver(localAddr string) *TCPReceiver {
+	return &TCPReceiver{
+		localAddr: localAddr,
+	}
+}
+
+func (r *TCPReceiver) Run() error {
+	lAddr, err := net.ResolveTCPAddr("tcp", r.localAddr)
+	if err != nil {
+		return fmt.Errorf("resolving local tcp addr: '%s': %w", r.localAddr, err)
+	}
+
+	listener, err := net.ListenTCP("tcp", lAddr)
+	if err != nil {
+		return fmt.Errorf("creating TCP listener for local address: %w", err)
+	}
+
+	for {
+		conn, err := listener.AcceptTCP()
+		if err != nil {
+			fmt.Printf("failed to accept TCP connection: %s", err.Error())
+		}
+	}
+
+	return nil
+}
+
+// TCPSender is responsible for the sending
+// of the incoming tcp connections to
+// desired TCP location.
+type TCPSender struct {
+	// pipes is a map of ipaddr string
+	// and channel of bytes used to send
+	// TCP connection to desired location
+	pipes      map[string]any
+	remoteAddr string
+}
+
+func NewTCPSender(remoteAddr string) *TCPSender {
+	return &TCPSender{
+		pipes:      make(map[string]any),
+		remoteAddr: remoteAddr,
+	}
+}
+
+func (s *TCPSender) Run() error {
+	rAddr, err := net.ResolveTCPAddr("tcp", r.remoteAddr)
+	if err != nil {
+		return fmt.Errorf("resolving remote tcp addr: '%s': %w", r.remoteAddr, err)
+	}
+}
+
+type senderConstruct struct {
+	locationIPAddr *net.IPAddr
+}