Add non-empty constraint for UserSocialAuth uid

Any empty uids are surely erroneous, and better to have integrity errors
than having users start sharing accounts when logging in.

Author: aleksanb

social_django/migrations/0017_usersocialauth_user_social_auth_uid_required.py

@@ -0,0 +1,22 @@
+# Generated by Django 5.1.7 on 2025-03-14 12:16
+
+from django.conf import settings
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("social_django", "0016_alter_usersocialauth_extra_data"),
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+    ]
+
+    operations = [
+        migrations.AddConstraint(
+            model_name="usersocialauth",
+            constraint=models.CheckConstraint(
+                check=models.Q(("uid", ""), _negated=True),
+                name="user_social_auth_uid_required",
+            ),
+        ),
+    ]

social_django/models.py

@@ -43,6 +43,11 @@ def __str__(self):
 
     class Meta:
         app_label = "social_django"
+        constraints = [
+            models.CheckConstraint(
+                check=~models.Q(uid=""), name="user_social_auth_uid_required"
+            ),
+        ]
         abstract = True
 
     @classmethod
@@ -70,7 +75,7 @@ def user_model(cls):
 class UserSocialAuth(AbstractUserSocialAuth):
     """Social Auth association model"""
 
-    class Meta:
+    class Meta(AbstractUserSocialAuth.Meta):
         """Meta data"""
 
         app_label = "social_django"