fix: add cascade to user_metrics (#1158)

Closes #1157.

Author: leafty

components/renku_data_services/migrations/versions/4cbb36ac2a5c_add_cascade_to_user_metrics.py

@@ -0,0 +1,36 @@
+"""add cascade to user_metrics
+
+Revision ID: 4cbb36ac2a5c
+Revises: bd97866a6253
+Create Date: 2026-01-06 12:43:03.843315
+
+"""
+
+from alembic import op
+
+# revision identifiers, used by Alembic.
+revision = "4cbb36ac2a5c"
+down_revision = "bd97866a6253"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.drop_constraint("user_metrics_id_fkey", "user_metrics", schema="users", type_="foreignkey")
+    op.create_foreign_key(
+        "user_metrics_id_fkey",
+        "user_metrics",
+        "users",
+        ["id"],
+        ["id"],
+        source_schema="users",
+        referent_schema="users",
+        ondelete="CASCADE",
+    )
+
+
+def downgrade() -> None:
+    op.drop_constraint("user_metrics_id_fkey", "user_metrics", schema="users", type_="foreignkey")
+    op.create_foreign_key(
+        "user_metrics_id_fkey", "user_metrics", "users", ["id"], ["id"], source_schema="users", referent_schema="users"
+    )

components/renku_data_services/users/orm.py

@@ -63,7 +63,9 @@ class UserMetricsORM(BaseORM):
     """Users metrics data."""
 
     __tablename__ = "user_metrics"
-    id: Mapped[int] = mapped_column(ForeignKey(UserORM.id), primary_key=True)
+    id: Mapped[int] = mapped_column(
+        ForeignKey(UserORM.id, ondelete="CASCADE", name="user_metrics_id_fkey"), primary_key=True
+    )
 
     metrics_identity_hash: Mapped[str | None] = mapped_column(String(), default=None, init=False)
     """Hash of the identity sent for metrics."""