FilesystemStore: securecookie: the value is not valid

[flux-i]

Sample code picked from :#78 (comment)
I modified the code a bit using FilesystemStore, i am getting securecookie error: value is not valid.
PS: This is my first time submitting a issue on git, have mercy if there are any problems in the post

import (
	"fmt"
	"log"
	"net/http"

	"github.com/gorilla/mux"
	"github.com/gorilla/sessions"
)

type Handler struct {
	Fstore *sessions.FilesystemStore
}

func main() {
	mux := mux.NewRouter()

	h := Handler{}
	h.Fstore = sessions.NewFilesystemStore("", []byte("key-1"), nil)
	mux.HandleFunc("/set", h.SetHandler)
	mux.HandleFunc("/delete", h.DeleteHandler)

	log.Fatal(http.ListenAndServe("localhost:8010", mux))
}

func (h *Handler) SetHandler(w http.ResponseWriter, r *http.Request) {
	sess, err := h.Fstore.Get(r, "app")
	if err != nil {
		http.Error(w, err.Error(), 400)
		return
	}

	log.Printf("value before: %v", sess.Values["user"])

	sess.Values["user"] = "gorilla!"
	err = sess.Save(r, w)
	if err != nil {
		http.Error(w, err.Error(), 400)
		return
	}

	fmt.Fprintf(w, "Cookie set to %v", sess.Values)
}

func (h *Handler) DeleteHandler(w http.ResponseWriter, r *http.Request) {
	sess, err := h.Fstore.Get(r, "app")
	if err != nil {
		http.Error(w, err.Error(), 400)
		return
	}

	sess.Options.MaxAge = -1

	err = sess.Save(r, w)
	if err != nil {
		http.Error(w, err.Error(), 400)
		return
	}
	log.Println("deleted")
}

[stale]

This issue has been automatically marked as stale because it hasn't seen a recent update. It'll be automatically closed in a few days.

[Kichiyaki]

That error is normal if you change the secret key and you didn't clear your browser's cookies.

[elithrar]

Correct. You likely want to persist the key outside of source code - changing the key will result in old session cookies being invalid.

[stale]

This issue has been automatically marked as stale because it hasn't seen a recent update. It'll be automatically closed in a few days.