From 022619246e8a53209b0ba4e44612aa8b29fc4923 Mon Sep 17 00:00:00 2001
From: bronku <bronk.jakub@proton.me>
Date: Sat, 5 Apr 2025 11:39:15 +0200
Subject: [PATCH] logout button

---
 TODO.md                                     |  2 +-
 internal/auth/auth.go                       |  1 +
 internal/auth/session.go                    | 23 +++++++++++++++++++++
 internal/server/templates/layout/nav.gohtml |  1 +
 internal/store/session.go                   |  6 ++++++
 5 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/TODO.md b/TODO.md
index 2277257..d6d72d7 100644
--- a/TODO.md
+++ b/TODO.md
@@ -30,7 +30,7 @@
 - [x] Authentication System
   - [x] Persistent logins across server restarts
   - [x] User login
-  - [ ] User logout
+  - [x] User logout
   - [ ] Role-based access (admin, staff)
   - [x] Password hashing
 - [ ] CSRF Protection
diff --git a/internal/auth/auth.go b/internal/auth/auth.go
index 3dc20b6..10dce25 100644
--- a/internal/auth/auth.go
+++ b/internal/auth/auth.go
@@ -43,6 +43,7 @@ func (a *Authenticator) Middleware(in http.Handler) http.Handler {
 	handler := http.NewServeMux()
 	handler.HandleFunc("GET /login", getLogin)
 	handler.HandleFunc("POST /login", a.login)
+	handler.HandleFunc("GET /logout", a.logout)
 	handler.Handle("/", a.ensureAuth(in))
 	return handler
 }
diff --git a/internal/auth/session.go b/internal/auth/session.go
index f4afa1c..6add9dc 100644
--- a/internal/auth/session.go
+++ b/internal/auth/session.go
@@ -50,3 +50,26 @@ func (a *Authenticator) login(w http.ResponseWriter, r *http.Request) {
 	http.SetCookie(w, &cookie)
 	http.Redirect(w, r, "/", http.StatusFound)
 }
+
+func (a *Authenticator) logout(w http.ResponseWriter, r *http.Request) {
+	var cookie http.Cookie
+	cookie.Name = "token"
+	cookie.Value = "nil"
+	cookie.HttpOnly = true
+	cookie.SameSite = http.SameSiteStrictMode
+	cookie.Path = "/"
+	http.SetCookie(w, &cookie)
+	http.Redirect(w, r, "/", http.StatusFound)
+	c, err := r.Cookie("token")
+	if err != nil {
+		return
+	}
+	_, ok := a.sessions[c.Value]
+	if !ok {
+		return
+	}
+	fmt.Println("removing session")
+	delete(a.sessions, c.Value)
+	err = a.s.RevokeSession(c.Value)
+	fmt.Println(err)
+}
diff --git a/internal/server/templates/layout/nav.gohtml b/internal/server/templates/layout/nav.gohtml
index b6fd88d..6c7c96e 100644
--- a/internal/server/templates/layout/nav.gohtml
+++ b/internal/server/templates/layout/nav.gohtml
@@ -3,4 +3,5 @@
 <a href="/order">New order</a>
 <a href="/cakes">All Cakes</a>
 <a href="/cake">New Cake</a>
+<a href="/logout">Logout</a>
 {{end}}
diff --git a/internal/store/session.go b/internal/store/session.go
index b34c551..76d5b8d 100644
--- a/internal/store/session.go
+++ b/internal/store/session.go
@@ -12,6 +12,12 @@ func (s *Store) AddSession(token, userName string, expiration time.Time) error {
 	return err
 }
 
+func (s *Store) RevokeSession(token string) error {
+	query := "delete from session where token = ?;"
+	_, err := s.db.Exec(query, token)
+	return err
+}
+
 func (s *Store) CleanSessions() error {
 	now := time.Now().Format("2006-01-02 15:04")
 	query := "delete from session where expiration < ?;"