package main

import (
    "fmt"
    "io"
    "log"
    "net"
    "os"
    "compress/gzip"
)

func main() {
    uploadFile("./aFile", "localhost:4040")
}

func uploadFile(srcFile, serverAddr string) {
    // connect to server
    conn, err := net.Dial("tcp", serverAddr)
    CheckError(err)
    defer conn.Close()

    in, err := os.Open(srcFile)
    if err != nil {
        log.Fatal(err)
    }
    pr, pw := io.Pipe()
    gw, err := gzip.NewWriterLevel(pw, 7)
    CheckError(err)
    go func() {
        n, err := io.Copy(gw, in)
        gw.Close()
        pw.Close()
        log.Printf("copied    %v %v", n, err)
    }()
    _, err = io.Copy(conn, pr)
    CheckError(err)
}

func CheckError(err error) {
    if err != nil {
        fmt.Fprintf(os.Stderr, "Fatal error: %s", err.Error())
        os.Exit(1)
    }
}