From ead851893ad10aae01f4918faa565837c88ade9c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20P=C3=A9pin?= <kerl@wkerl.me>
Date: Sun, 17 May 2020 17:36:15 +0200
Subject: [PATCH] Test the logout view

---
 .../0002_casaccount_connected_to_cas.py       |  6 +-
 authens/tests/test_views.py                   | 63 +++++++++++++++++++
 tests/settings.py                             | 29 +++++++++
 tests/urls.py                                 |  4 ++
 4 files changed, 99 insertions(+), 3 deletions(-)
 create mode 100644 authens/tests/test_views.py
 create mode 100644 tests/urls.py

diff --git a/authens/migrations/0002_casaccount_connected_to_cas.py b/authens/migrations/0002_casaccount_connected_to_cas.py
index 84910a3..9559757 100644
--- a/authens/migrations/0002_casaccount_connected_to_cas.py
+++ b/authens/migrations/0002_casaccount_connected_to_cas.py
@@ -6,13 +6,13 @@ from django.db import migrations, models
 class Migration(migrations.Migration):
 
     dependencies = [
-        ('authens', '0001_initial'),
+        ("authens", "0001_initial"),
     ]
 
     operations = [
         migrations.AddField(
-            model_name='casaccount',
-            name='connected_to_cas',
+            model_name="casaccount",
+            name="connected_to_cas",
             field=models.BooleanField(default=False, editable=False),
         ),
     ]
diff --git a/authens/tests/test_views.py b/authens/tests/test_views.py
new file mode 100644
index 0000000..4ad5176
--- /dev/null
+++ b/authens/tests/test_views.py
@@ -0,0 +1,63 @@
+from unittest.mock import patch
+
+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 authens.models import CASAccount
+from authens.tests.cas_utils import FakeCASClient
+
+UserModel = get_user_model()
+
+
+class TestLogoutView(TestCase):
+    def test_regular_logout(self):
+        # Regular user (without a CAS account)
+        user = UserModel.objects.create_user(username="johndoe")
+
+        # Log the user in
+        client = Client()
+        client.force_login(user)
+
+        self.assertEqual(Session.objects.count(), 1)
+        response = client.get("/authens/logout")
+        self.assertEqual(Session.objects.count(), 0)  # User is actually logged out.
+        self.assertRedirects(response, settings.LOGOUT_REDIRECT_URL)
+
+    @patch("authens.backends.get_cas_client")
+    def test_cas_logout(self, mock_cas_client):
+        # Make `get_cas_client` return a dummy CAS client that skips ticket verification
+        # and always log in a user with CAS login 'johndoe'.
+        # This is only used for login.
+        mock_cas_client.return_value = FakeCASClient("johndoe", 2019)
+
+        # CAS user
+        user = UserModel.objects.create_user(username="johndoe")
+        CASAccount.objects.create(user=user, cas_login="johndoe", entrance_year=2019)
+
+        # Log the user in via CAS
+        client = Client()
+        client.login(ticket="dummy ticket")
+
+        self.assertEqual(Session.objects.count(), 1)
+        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
+        )
+
+    def test_regular_logout_on_cas_account(self):
+        # CAS user
+        user = UserModel.objects.create_user(username="johndoe", password="p4ssw0rd")
+        CASAccount.objects.create(user=user, cas_login="johndoe", entrance_year=2019)
+
+        # Log the user in by password and *not* via CAS
+        client = Client()
+        client.login(username="johndoe", password="p4ssw0rd")
+
+        self.assertEqual(Session.objects.count(), 1)
+        response = client.get("/authens/logout")
+        self.assertEqual(Session.objects.count(), 0)  # User is logged out…
+        # … and not redirected to the CAS logout page.
+        self.assertRedirects(response, settings.LOGOUT_REDIRECT_URL)
diff --git a/tests/settings.py b/tests/settings.py
index 999e477..04168fd 100644
--- a/tests/settings.py
+++ b/tests/settings.py
@@ -8,6 +8,7 @@ SECRET_KEY = "dummy"
 INSTALLED_APPS = [
     "django.contrib.contenttypes",
     "django.contrib.auth",
+    "django.contrib.sessions",
     "authens",
     "tests",
 ]
@@ -17,6 +18,34 @@ AUTHENTICATION_BACKENDS = [
     "authens.backends.ENSCASBackend",
 ]
 
+MIDDLEWARE = [
+    'django.middleware.security.SecurityMiddleware',
+    'django.contrib.sessions.middleware.SessionMiddleware',
+    'django.middleware.common.CommonMiddleware',
+    'django.middleware.csrf.CsrfViewMiddleware',
+    'django.contrib.auth.middleware.AuthenticationMiddleware',
+    'django.contrib.messages.middleware.MessageMiddleware',
+    'django.middleware.clickjacking.XFrameOptionsMiddleware',
+]
+
+TEMPLATES = [
+    {
+        "BACKEND": "django.template.backends.django.DjangoTemplates",
+        "DIRS": [],
+        "APP_DIRS": True,
+        "OPTIONS": {
+            "context_processors": [
+                "django.template.context_processors.debug",
+                "django.template.context_processors.request",
+                "django.contrib.auth.context_processors.auth",
+                "django.contrib.messages.context_processors.messages",
+            ],
+        },
+    },
+]
+
 DATABASES = {"default": {"ENGINE": "django.db.backends.sqlite3"}}
 
+ROOT_URLCONF = "tests.urls"
 LOGIN_URL = reverse_lazy("authens:login")
+LOGOUT_REDIRECT_URL = reverse_lazy("authens:login")
diff --git a/tests/urls.py b/tests/urls.py
new file mode 100644
index 0000000..2b6ab10
--- /dev/null
+++ b/tests/urls.py
@@ -0,0 +1,4 @@
+from django.urls import include, path
+
+
+urlpatterns = [path("authens/", include("authens.urls"))]