ldap: add external_id's case-insensitive comparison (#27147)

src/authentic2/backends/ldap_backend.py

@@ -837,7 +837,7 @@ class LDAPBackend(object):
             try:
                 log.debug('lookup using external_id %r: %r', eid_tuple, external_id)
                 return LDAPUser.objects.prefetch_related('groups').get(
-                    userexternalid__external_id=external_id, userexternalid__source=block['realm'])
+                    userexternalid__external_id__iexact=external_id, userexternalid__source=block['realm'])
             except User.DoesNotExist:
                 pass
 

tests/test_ldap.py

@@ -404,6 +404,18 @@ def test_get_users(slapd, settings):
     assert save.call_count == 3
     assert bulk_create.call_count == 1
 
+    # uppercase user uid in the directory and check that no new user is created
+    conn = slapd.get_connection_admin()
+    ldif = [(ldap.MOD_REPLACE, 'uid', UID.upper())]
+    conn.modify_s(DN, ldif)
+    save.reset_mock()
+    bulk_create.reset_mock()
+    users = list(ldap_backend.LDAPBackend.get_users())
+    assert len(users) == 101
+    assert User.objects.count() == 101
+    assert save.call_count == 0
+    assert bulk_create.call_count == 0
+
 
 @pytest.mark.django_db
 def test_set_mandatory_roles(slapd, settings):