From 8e95a0164722c625843fd5a7c1dea3e9477f1679 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20P=C3=A9pin?= <kerl@wkerl.me>
Date: Wed, 10 Jun 2020 22:22:13 +0200
Subject: [PATCH] Redirect after a CAS logout

---
 authens/tests/test_views.py |  8 +++++++-
 authens/views.py            | 11 ++++++++---
 2 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/authens/tests/test_views.py b/authens/tests/test_views.py
index 25dddb8..94d27c2 100644
--- a/authens/tests/test_views.py
+++ b/authens/tests/test_views.py
@@ -1,9 +1,11 @@
 from unittest.mock import patch
+from urllib.parse import quote as urlquote
 
 from django.conf import settings
 from django.contrib.auth import get_user_model
 from django.contrib.sessions.models import Session
 from django.test import Client, TestCase
+from django.urls import reverse
 
 from authens.models import CASAccount
 from authens.tests.cas_utils import FakeCASClient
@@ -44,7 +46,11 @@ class TestLogoutView(TestCase):
         response = client.get("/authens/logout")
         self.assertEqual(Session.objects.count(), 0)  # User is logged out…
         self.assertRedirects(  # … and redirected to the CAS logout page.
-            response, "https://cas.eleves.ens.fr/logout", fetch_redirect_response=False
+            response,
+            "https://cas.eleves.ens.fr/logout?service={}".format(
+                urlquote("http://testserver" + reverse("authens:login"))
+            ),
+            fetch_redirect_response=False,
         )
 
     def test_regular_logout_on_cas_account(self):
diff --git a/authens/views.py b/authens/views.py
index da17c48..194814f 100644
--- a/authens/views.py
+++ b/authens/views.py
@@ -1,3 +1,5 @@
+from urllib.parse import urlunparse
+
 from django.conf import settings
 from django.contrib import auth
 from django.contrib.auth import views as auth_views
@@ -93,8 +95,11 @@ class LogoutView(auth_views.LogoutView):
             self.cas_connected = False
 
     def get_next_page(self):
+        next_page = super().get_next_page()
         if self.cas_connected:
             cas_client = get_cas_client(self.request)
-            return cas_client.get_logout_url()
-        else:
-            return super().get_next_page()
+            redirect_url = urlunparse(
+                (self.request.scheme, self.request.get_host(), next_page, "", "", "")
+            )
+            next_page = cas_client.get_logout_url(redirect_url=redirect_url)
+        return next_page