go-server-cookies.go

package main

import (
    "fmt"
    "log"

    "flag"

    "net/http"
)

var (
    port int
)

func authHandler(w http.ResponseWriter, r *http.Request) {
    // http://golang.org/pkg/net/http/#Cookie
    cookie := &http.Cookie{
        Name: "token", 
        Value: "foobar",
    }

    http.SetCookie(w, cookie)
}

func rootHandler(w http.ResponseWriter, r *http.Request) {
    if c, err := r.Cookie("token"); err != nil || c.Value != "foobar" {
        http.Error(w, "Ah ah ah, you didn't say the magic word", 401)
        return
    }

    fmt.Fprintf(w, "Access granted")
}

func init() {
    flag.IntVar(&port, "port", 8080, "HTTP Server Port")

    flag.Parse()
}

func main() {
    httpAddr := fmt.Sprintf(":%v", port)

    log.Printf("Listening to %v", httpAddr)

    // visit /auth to create a cookie
    http.HandleFunc("/auth", authHandler)

    // visit / to check cookie
    http.HandleFunc("/", rootHandler)

    log.Fatal(http.ListenAndServe(httpAddr, nil))
}