From 6681b7ade7fb1b0c3a366167383ec0fdb5c023e2 Mon Sep 17 00:00:00 2001
From: d3vyce <44915747+d3vyce@users.noreply.github.com>
Date: Tue, 24 Mar 2026 19:56:03 +0100
Subject: [PATCH] fix: defer on_create/on_update/on_delete dispatch until
 outermost transaction commits (#172)

---
 src/fastapi_toolsets/models/watched.py | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/src/fastapi_toolsets/models/watched.py b/src/fastapi_toolsets/models/watched.py
index 00e1e5c..6198e48 100644
--- a/src/fastapi_toolsets/models/watched.py
+++ b/src/fastapi_toolsets/models/watched.py
@@ -26,6 +26,7 @@ _SESSION_PENDING_NEW = "_ft_pending_new"
 _SESSION_CREATES = "_ft_creates"
 _SESSION_DELETES = "_ft_deletes"
 _SESSION_UPDATES = "_ft_updates"
+_SESSION_SAVEPOINT_DEPTH = "_ft_sp_depth"
 
 
 class ModelEvent(str, Enum):
@@ -92,6 +93,22 @@ def _upsert_changes(
         pending[key] = (obj, changes)
 
 
+@event.listens_for(AsyncSession.sync_session_class, "after_transaction_create")
+def _after_transaction_create(session: Any, transaction: Any) -> None:
+    if transaction.nested:
+        session.info[_SESSION_SAVEPOINT_DEPTH] = (
+            session.info.get(_SESSION_SAVEPOINT_DEPTH, 0) + 1
+        )
+
+
+@event.listens_for(AsyncSession.sync_session_class, "after_transaction_end")
+def _after_transaction_end(session: Any, transaction: Any) -> None:
+    if transaction.nested:
+        depth = session.info.get(_SESSION_SAVEPOINT_DEPTH, 0)
+        if depth > 0:  # pragma: no branch
+            session.info[_SESSION_SAVEPOINT_DEPTH] = depth - 1
+
+
 @event.listens_for(AsyncSession.sync_session_class, "after_flush")
 def _after_flush(session: Any, flush_context: Any) -> None:
     # New objects: capture references while session.new is still populated.
@@ -189,6 +206,9 @@ def _schedule_with_snapshot(
 
 @event.listens_for(AsyncSession.sync_session_class, "after_commit")
 def _after_commit(session: Any) -> None:
+    if session.info.get(_SESSION_SAVEPOINT_DEPTH, 0) > 0:
+        return
+
     creates: list[Any] = session.info.pop(_SESSION_CREATES, [])
     deletes: list[Any] = session.info.pop(_SESSION_DELETES, [])
     field_changes: dict[int, tuple[Any, dict[str, dict[str, Any]]]] = session.info.pop(