isLoggedIn.go

// Check if the user is logged in, true if they do
func IsLoggedIn(r *http.Request) bool {

        // Obtains cookie from users http.Request
	cookie, err := r.Cookie("SessionID")
	if err != nil {
		fmt.Println(err)
		return false
	}

        // Obtain sessionID from cookie we obtained earlier
	sessionID := cookie.Value

        // Split the sessionID to Username and ID (username+random)        
	z := strings.Split(sessionID, ":")
	email := z[0]
	sessionID = z[1]

        // Returns the expectedSessionID from the database
	expectedSessionID, errz := lookupSessionID(email)

	if errz != "" {
		fmt.Println(errz)
		return false
	}

        // If SessionID matches the expected SessionID, it is Good
	if sessionID == expectedSessionID {
            // If you want to be really secure check IP
	    return true
	}

	return false
}