fix(daemons): block owner transfer while assigned

tests/test_bat022_req053_admin_daemon_crud.py

@@ -9,6 +9,7 @@ import pytest
 from fastapi.testclient import TestClient
 
 from app.core.config import Settings, get_settings
+from app.domain.errors import DaemonInUseError
 from app.domain.models import BrokerCredential, Daemon, TokenPrincipal, User
 from app.main import create_app
 from app.repositories.postgres import PostgresPortfolioRepository
@@ -212,6 +213,33 @@ def test_admin_patch_owner_invalidates_credentials() -> None:
     mock_repo.update_daemon_owner.assert_called_once_with(DAEMON_ID, owner_user_id=OWNER_B_ID)
 
 
+def test_admin_patch_referenced_daemon_owner_returns_409() -> None:
+    """Issue #27: assigned daemon owner transfer fails without a partial mutation."""
+    settings = _make_settings()
+    principal = _make_admin_principal()
+    daemon_before = _make_daemon(owner_user_id=OWNER_A_ID)
+
+    mock_repo = MagicMock()
+    mock_repo.get_token_principal.return_value = principal
+    mock_repo.get_daemon_by_id.return_value = daemon_before
+    mock_repo.update_daemon_owner.side_effect = DaemonInUseError(
+        "배정된 포트폴리오가 있는 daemon의 소유자는 변경할 수 없습니다"
+    )
+
+    with patch("app.core.auth.get_portfolio_repository_from_settings", return_value=mock_repo), \
+         patch("app.api.v1_admin_daemons.get_portfolio_repository_from_settings", return_value=mock_repo):
+        client = _make_client(settings, mock_repo)
+        resp = client.patch(
+            f"/v1/admin/daemons/{DAEMON_ID}",
+            json={"owner_user_id": OWNER_B_ID},
+            headers=_auth_header(),
+        )
+
+    assert resp.status_code == 409
+    mock_repo.update_daemon_owner.assert_called_once_with(DAEMON_ID, owner_user_id=OWNER_B_ID)
+    mock_repo.update_daemon.assert_not_called()
+
+
 # ---------------------------------------------------------------------------
 # REQ-053 AC-5: owner 변경 후 이전 owner의 /v1/user_info → broker=null
 # (verified via update_daemon_owner deleting credentials; AC-4 covers the mechanism)
@@ -489,7 +517,9 @@ def _make_mock_conn_for_owner_update(*, fail_on_update: bool = False):
         def execute(self, sql: str, params=None) -> None:
             sql_stripped = sql.strip()
             executed_sqls.append(sql_stripped)
-            if sql_stripped.startswith("SELECT"):
+            if "FROM portfolios" in sql_stripped:
+                self._rows = []
+            elif sql_stripped.startswith("SELECT"):
                 # daemon exists
                 self._rows = [("daemon-001",)]
             elif sql_stripped.startswith("DELETE"):
@@ -717,6 +747,8 @@ def test_update_daemon_owner_both_ops_in_single_transaction() -> None:
 
         def fetchone(self):
             sql = executed_sqls[-1] if executed_sqls else ""
+            if "FROM portfolios" in sql:
+                return None
             if sql.startswith("SELECT"):
                 return ("daemon-001",)
             if sql.startswith("UPDATE"):