How to assign BSON _Id to a cookie (Go, Mongodb)

I was trying to create a go cookie. I want to assign Id from Mongodb to be stored in the Cookie. But while compiling I am getting an error as follows:-

"unknown http.Cookie field 'Id' in struct literal"

The following is my code:-

getUser := user.CheckDB()
expiration := time.Now().Add(365 * 24 * time.Hour)

//The Error is Caused by the Next Line
cookie := http.Cookie{Id: getUser[0].Id, Name: getUser[0].Email, Value: getUser[0].Password, Expires: expiration}
http.SetCookie(w, &cookie)



func (this *User) CheckDB() []User {
	var results []User
	sess, db := GetDatabase()
	defer sess.Close()
	c := db.C("user")
	uname := &this.Email
	err := c.Find(bson.M{"email": *uname}).Sort("-id").All(&results)
	if err != nil {
		panic(err)
	} else {
		fmt.Println("Results All: ", results)
		return results
	}
}

type Cookie struct {
	Id         bson.ObjectId `bson:"_id,omitempty"`
	Name       string
	Value      string
	Path       string
	Domain     string
	Expires    time.Time
	RawExpires string
	MaxAge     int
	Secure     bool
	HttpOnly   bool
	Raw        string
	Unparsed   []string
}

Thanks in advance.

Here is a solution for this problem.

Cookie struct below:

type Cookie struct {	
    Name       string
    Value      string
    Path       string
    Domain     string
    Expires    time.Time
    RawExpires string
    MaxAge   int
    Secure   bool
    HttpOnly bool
    Raw      string
    Unparsed []string
}

Cookie Creation

 value := map[string]string{
        "id": cookieId,
    }
    if encoded, err := ckieHandler.Encode("session", value); err == nil {
        cookie := &http.Cookie{
        Name:  "session",
        Value: encoded,
        Path:  "/",
    	}
    	http.SetCookie(response, cookie)
    }

Cookie Call

if cookie, err := request.Cookie("session"); err == nil {
        cookieValue := make(map[string]string)
        if err = ckieHandler.Decode("session", cookie.Value, &cookieValue); err == nil {
            id = cookieValue["id"] // **Pass BSON ID here**
        }
    }

For more details Click Here. This link helped me a lot. Hoping someone will find this answer useful.