Merge branch 'configurable_backend' into 'master'

Ajoute un hook pour choisir le username des users générés

See merge request klub-dev-ens/authens!2

authens/backends.py

@@ -30,21 +30,6 @@ def get_entrance_year(attributes):
         return 2000 + year
 
 
-def find_available_username(clipper_uid):
-    """Find an available username 'close' to a clipper uid."""
-
-    taken = UserModel.objects.filter(username__startswith=clipper_uid).values_list(
-        "username", flat=True
-    )
-    if clipper_uid not in taken:
-        return clipper_uid
-    else:
-        i = 2
-        while clipper_uid + str(i) in taken:
-            i += 1
-        return clipper_uid + str(i)
-
-
 class ENSCASBackend:
     """ENSAuth authentication backend.
 
@@ -72,6 +57,31 @@ class ENSCASBackend:
         year = get_entrance_year(attributes)
         return self._get_or_create(uid, year)
 
+    def get_free_username(self, clipper_uid):
+        """Find an available username for the new user.
+
+        If you override this method, make sure it returns a username that is not taken
+        by any existing user.
+        This method will be called from within an atomic database transation (don't
+        worry about data races).
+        """
+
+        taken = UserModel.objects.values_list("username", flat=True)
+
+        # This should handle most cases and produce a nice username.
+        prefered = [clipper_uid, "cas_" + clipper_uid]
+        pref_taken = taken.filter(username__in=prefered)
+        for name in prefered:
+            if name not in pref_taken:
+                return name
+
+        # Worst case: generate a username of the form clipper_uid + int
+        taken = taken.filter(username__startswith=clipper_uid)
+        i = 2
+        while clipper_uid + str(i) in taken:
+            i += 1
+        return clipper_uid + str(i)
+
     def _get_or_create(self, uid, entrance_year):
         with transaction.atomic():
             try:
@@ -83,7 +93,7 @@ class ENSCASBackend:
                 user = None
 
             if user is None:
-                username = find_available_username(uid)
+                username = self.get_free_username(uid)
                 user = UserModel.objects.create_user(username=username)
                 Clipper.objects.create(user=user, entrance_year=entrance_year, uid=uid)
         return user

authens/tests/test_backend.py

@@ -0,0 +1,25 @@
+from django.contrib.auth import get_user_model
+from django.test import TestCase
+
+from authens.backends import ENSCASBackend
+
+UserModel = get_user_model()
+
+
+class TestBackend(TestCase):
+    def setUp(self):
+        UserModel.objects.create(username="toto")
+        UserModel.objects.create(username="toto2")
+
+    def test_usernames_uniqueness(self):
+        backend = ENSCASBackend()
+        for _ in range(10):
+            username = backend.get_free_username("toto")
+            self.assertFalse(UserModel.objects.filter(username=username).exists())
+            UserModel.objects.create(username=username)
+        for _ in range(10):
+            username = backend.get_free_username("tutu")
+            self.assertFalse(UserModel.objects.filter(username=username).exists())
+            UserModel.objects.create(username=username)
+
+    # TODO: https://git.eleves.ens.fr/klub-dev-ens/authens/issues/4

runtests.py

@@ -0,0 +1,17 @@
+# Source:
+# https://docs.djangoproject.com/en/3.0/topics/testing/advanced/#using-the-django-test-runner-to-test-reusable-applications
+
+import os
+import sys
+
+import django
+from django.conf import settings
+from django.test.utils import get_runner
+
+if __name__ == '__main__':
+    os.environ['DJANGO_SETTINGS_MODULE'] = 'tests.settings'
+    django.setup()
+    TestRunner = get_runner(settings)
+    test_runner = TestRunner()
+    failures = test_runner.run_tests(sys.argv[1:])
+    sys.exit(bool(failures))

tests/settings.py

@@ -0,0 +1,22 @@
+from django.urls import reverse_lazy  # noqa
+
+# Minimal settings to run a django app using authens.
+
+
+SECRET_KEY = "dummy"
+
+INSTALLED_APPS = [
+    "django.contrib.contenttypes",
+    "django.contrib.auth",
+    "authens",
+    "tests",
+]
+
+AUTHENTICATION_BACKENDS = [
+    "django.contrib.auth.backends.ModelBackend",
+    "authens.backends.ENSCASBackend",
+]
+
+DATABASES = {"default": {"ENGINE": "django.db.backends.sqlite3"}}
+
+LOGIN_URL = reverse_lazy("authens:login")