http_cookie.go

flash_message.go

package main

import (
	"net/http"
	"encoding/base64"
	"fmt"
	"time"
)

func setMessage(w http.ResponseWriter, r *http.Request) {
	msg := []byte("Hello World")
	c := http.Cookie{
		Name: "flash",
		Value: base64.URLEncoding.EncodeToString(msg),
	}
	http.SetCookie(w, &c)
}

func showMessage(w http.ResponseWriter, r *http.Request) {
	c, err := r.Cookie("flash")
	if err != nil {
		if err == http.ErrNoCookie {
			fmt.Fprintln(w, "No Message found")
		}
	} else {
		rc := http.Cookie {
			Name: "flash",
			MaxAge: -1,
			Expires: time.Unix(1, 0),
		}
		http.SetCookie(w, &rc)
		val, _ := base64.URLEncoding.DecodeString(c.Value)
		fmt.Fprintln(w, string(val))
	}
}

func main() {
	server := http.Server {
		Addr: "127.0.0.1:8080",
	}
	http.HandleFunc("/set_message", setMessage)
	http.HandleFunc("/show_message", showMessage)
	server.ListenAndServe()
}

http_cookie.go

package main

import (
	"net/http"
	"fmt"
)

func setCookie(w http.ResponseWriter, r *http.Request) {
	c1 := http.Cookie{
		Name: "first_cookie",
		Value: "Go Web Programming",
		HttpOnly: true,
	}

	c2 := http.Cookie{
		Name: "second_cookie",
		Value: "publisher",
		HttpOnly: true,
	}

	w.Header().Set("Set-Cookie", c1.String())
	w.Header().Add("Set-Cookie", c2.String())
	//http.SetCookie(w, &c1)
	//http.SetCookie(w, &c2)
}

func getCookie(w http.ResponseWriter, r *http.Request) {
	h := r.Header["Cookie"]
	fmt.Fprintln(w, h)
}

func getCookie2(w http.ResponseWriter, r *http.Request) {
	c1, err := r.Cookie("first_cookie")
	if err != nil {
		fmt.Fprintln(w, "Cannot get the first cookie")
	}
	cs := r.Cookies()
	fmt.Fprintln(w, c1)
	fmt.Fprintln(w, cs)
}

func main() {
	server := http.Server{
		Addr: "127.0.0.1:8080",
	}


	http.HandleFunc("/set_cookie", setCookie)
	http.HandleFunc("/get_cookie", getCookie2)
	server.ListenAndServe()
}