Passing file with gob.

client.go

package main

import (
	"bufio"
	"encoding/gob"
	"log"
	"net"
	"os"
)

const CONN_TYPE = "tcp"

type NormalFile struct {
	Data *[]byte
}

func main() {
	if len(os.Args) < 3 {
		log.Fatal("Usage: go run client_gob.go 127.0.0.1:8080 filename")
	}

	serverAddr := os.Args[1]
	filename := os.Args[2]
	inputFile, err := os.Open(filename)
	if err != nil {
		log.Fatal(err)
	}
	defer inputFile.Close()

	fileStat, err := inputFile.Stat()
	if err != nil {
		log.Fatal(err)
	}

	// Read file content
	fileLength := fileStat.Size()
	dataBuffer := make([]byte, fileLength)
	r := bufio.NewReader(inputFile)
	n, err := r.Read(dataBuffer)
	if int64(n) != fileLength {
		log.Fatal("Cannot read full file")
	}

	// Connect to server and pass file
	tcpAddr, err := net.ResolveTCPAddr(CONN_TYPE, serverAddr)
	if err != nil {
		log.Fatal(err)
	}
	conn, err := net.DialTCP(CONN_TYPE, nil, tcpAddr)
	if err != nil {
		log.Fatal(err)
	}
	defer conn.Close()

	encBuf := bufio.NewWriter(conn)
	encoder := gob.NewEncoder(encBuf)
	err = encoder.Encode(NormalFile{&dataBuffer})
	if err != nil {
		log.Fatal(err)
	}

        reply := make([]byte, 1024)
        _, err = conn.Read(reply)
        if err != nil {
                log.Fatal(err)
        }
        log.Print(string(reply))
}

server.go

package main

import (
	"bufio"
	"encoding/gob"
        "fmt"
	"log"
	"net"
	"os"
        "time"
)

type NormalFile struct {
	Data *[]byte
}

const (
	CONN_HOST = ""
	CONN_PORT = "8080"
	CONN_TYPE = "tcp"
)

func main() {
	// Listen for incoming connections
	l, err := net.Listen(CONN_TYPE, CONN_HOST+":"+CONN_PORT)
	if err != nil {
		panic(err)
	}
	defer l.Close()

	log.Print("Listening on ", CONN_HOST+":"+CONN_PORT)
	for {
		conn, err := l.Accept()
		log.Print("Accepted one connection")
		if err != nil {
			panic(err)
		}
		go handleRequest(conn)
	}
}

func handleRequest(conn net.Conn) {
	defer conn.Close()

        filename := fmt.Sprintf("code%d.tar.gz", time.Now().Unix())
	fo, err := os.Create(filename)
	if err != nil {
		log.Print("Create file error")
		return
	}
	defer fo.Close()

	decBuf := bufio.NewReader(conn)
	decoder := gob.NewDecoder(decBuf)
	var codeFile NormalFile
	err = decoder.Decode(&codeFile)
	if err != nil {
		log.Fatal(err)
	}
	fo.Write(*codeFile.Data)

	conn.Write([]byte("File received."))
	log.Print("File received completely")
}