TCP File client server in go

client.go

package main

import (
	"fmt"
	"io"
	"net"
	"os"
)

const (
	portAddr = 9632
	proto    = "tcp"
	buffSize = 1024
)

var (
	ipAddr     net.IP = net.ParseIP("127.0.0.1")
	bufferRead        = make([]byte, buffSize)
)

func main() {
	// ptr to conf
	confTcp := &net.TCPAddr{
		IP:   ipAddr,
		Port: portAddr,
	}

	sock, err := net.DialTCP(proto, nil, confTcp)

	if err != nil {
		fmt.Fprintf(os.Stdout, "[#] \tCant create tcp socket dialer\n")
		fmt.Fprintf(os.Stderr, "[#] \t %s\n", err.Error())
		os.Exit(1)
	}

	fmt.Fprintf(os.Stdout, "[#] \t Server said \n")

	for {
		n, err := sock.Read(bufferRead)

		if err != nil && err != io.EOF {
			fmt.Fprintf(os.Stdout, "\n[#] \tCant read from tcp socket\n")
			fmt.Fprintf(os.Stderr, "[#], \t %s\n", err.Error())
			break
		}

		if n > 0 {
			fmt.Fprintf(os.Stdout, "%s", string(bufferRead))
		} else {
			break
		}

	}

	defer func() {
		if err := sock.Close(); err != nil {
			panic(err)
		}
		fmt.Fprintf(os.Stdout, "\n[#] \t Client close connection\n")
	}()
}

file.txt

Lorem ipsum dolor sit amet, duis aliquet, vulputate consequat eros nunc, sapien mauris nullam, sit risus fugiat eleifend nunc. Turpis justo luctus tristique ridiculus, gravida morbi tellus sollicitudin in id. Consequat praesent nibh donec, erat ante nec eget, mollis lectus adipiscing, erat aut luctus cubilia ultrices, consequat amet maecenas quis. Morbi aliquam tempus eget vulputate wisi, dolor habitant est, aliquam magna, nunc porttitor vestibulum, dapibus libero vitae eu suspendisse lectus. Ipsum vel dignissim, lacus mollis nisl et tincidunt eros, at bibendum in tincidunt, augue aptent id ridiculus ante taciti sed, maecenas massa sed. A est. Quam aliquet, mauris at turpis semper augue, vitae cras pede a consequat congue lobortis, tristique nullam malesuada augue amet libero. Sapien in eget, at dui purus, vestibulum eget vel. In morbi pharetra nunc metus. Etiam nec erat nibh nunc, sint amet phasellus metus, sit suscipit mollis similique. Ipsum cras id, etiam morbi sed.

server.go

package main

import (
	"fmt"
	"io"
	"net"
	"os"
)

const (
	portAddr = 9632
	proto    = "tcp"
	buffSize = 1024
)

var (
	ipAddr net.IP = net.ParseIP("127.0.0.1")
	buffer        = make([]byte, buffSize)
)

func main() {

	// define our tcpAddr conf
	confTcp := &net.TCPAddr{
		IP:   ipAddr,
		Port: portAddr,
	}

	// create listen tcp sock
	sock, err := net.ListenTCP(proto, confTcp)

	if err != nil {
		fmt.Fprintf(os.Stdout, "[#] \tCant create tcp socket listener\n")
		fmt.Fprintf(os.Stderr, "[#] \t %s\n", err.Error())
		os.Exit(1)
	}

	fmt.Fprintf(os.Stdout, "[#] \tRunning the %s server %s : %d\n", proto, ipAddr.String(), portAddr)

	for {
		// forever client
		client, err := sock.Accept()

		if err != nil {
			fmt.Fprintf(os.Stderr, "[#] \t %s\n", err.Error())
			os.Exit(1)
		}

		fmt.Fprintf(os.Stdout, "[#] \tClient connected\n")

		manageFile(client, buffer, "file.txt")

		fmt.Fprintf(os.Stdout, "[#] \tClosing the client proto %s on conn %s\n", client.LocalAddr().Network(), client.LocalAddr().String())

		//close connection
		client.Close()

	}
}

func manageFile(sock net.Conn, buffer []byte, filePath string) {
	fp, err := os.Open(filePath)
	if err != nil {
		panic(err)
	}

	for {
		n, err := fp.Read(buffer)

		if err != nil && err != io.EOF {
			panic(err)
		}

		if n == 0 || err == io.EOF {
			break
		} else {
			m, err := sock.Write(buffer)
			if err != nil && m <= 0 {
				fmt.Fprintf(os.Stderr, "[#] \t Server can't send msg\n")
				os.Exit(1)
			}

		}

	}

	defer func() {
		if err := fp.Close(); err != nil {
			panic(err)
		}
	}()

}