Harden CalDAV write-back with retries (#1193)

Co-authored-by: Alexandre Teixeira <111787685+alteixeira20@users.noreply.github.com>

tests/test_caldav_bidirectional_sync.py

@@ -0,0 +1,169 @@
+"""Regression coverage for bidirectional CalDAV sync plumbing.
+
+These tests avoid a live CalDAV server. They pin the local invariants that keep
+Odysseus-created CalDAV events from being pruned before they can be pushed.
+"""
+
+from datetime import datetime
+import importlib.util
+from pathlib import Path
+import sys
+
+from src.caldav_writeback import build_event_ical
+
+
+def test_event_to_ical_serializes_core_fields_and_rrule():
+    ical = build_event_ical({
+        "uid": "evt-123",
+        "summary": "Planning",
+        "description": "Bring notes",
+        "location": "HQ",
+        "dtstart": datetime(2026, 6, 5, 9, 0),
+        "dtend": datetime(2026, 6, 5, 10, 0),
+        "all_day": False,
+        "is_utc": False,
+        "rrule": "FREQ=WEEKLY;COUNT=2",
+    })
+
+    assert "UID:evt-123" in ical
+    assert "SUMMARY:Planning" in ical
+    assert "DESCRIPTION:Bring notes" in ical
+    assert "LOCATION:HQ" in ical
+    assert "RRULE:FREQ=WEEKLY;COUNT=2" in ical
+
+
+def test_caldav_pull_prune_skips_unsynced_or_pending_local_rows():
+    source = Path("src/caldav_sync.py").read_text()
+
+    assert 'existing.caldav_sync_pending in {"create", "update"}' in source
+    assert "CalendarEvent.remote_href.isnot(None)" in source
+    assert "CalendarEvent.caldav_sync_pending.is_(None)" in source
+
+
+def test_http_calendar_writes_mark_pending_and_push_after_commit():
+    source = Path("routes/calendar_routes.py").read_text()
+
+    assert 'caldav_sync_pending="create" if cal.source == "caldav" else None' in source
+    assert 'ev.caldav_sync_pending = "update"' in source
+    assert 'await _push_caldav_event_after_commit(owner, uid, "create")' in source
+    assert 'await _push_caldav_event_after_commit(owner, base_uid, "update")' in source
+    assert 'await _push_caldav_event_after_commit(owner, base_uid, "delete")' in source
+    assert "_record_caldav_delete_tombstone(db, ev, owner)" in source
+    assert 'not result.get("ok")' in source
+
+
+def test_agent_calendar_writes_share_caldav_push_path():
+    source = Path("src/tool_implementations.py").read_text()
+
+    assert "_push_caldav_event_after_commit" in source
+    assert 'caldav_sync_pending="create" if cal.source == "caldav" else None' in source
+    assert 'ev.caldav_sync_pending = "update"' in source
+    assert 'await _push_caldav_event_after_commit(owner, uid, "create")' in source
+    assert 'await _push_caldav_event_after_commit(owner, base_uid, "update")' in source
+    assert 'await _push_caldav_event_after_commit(owner, base_uid, "delete")' in source
+    assert "_record_caldav_delete_tombstone(db, ev, owner)" in source
+
+
+def test_database_declares_and_migrates_caldav_remote_metadata():
+    source = Path("core/database.py").read_text()
+
+    for needle in [
+        "class CalendarDeletedEvent",
+        "remote_href = Column(String, nullable=True)",
+        "remote_etag = Column(String, nullable=True)",
+        "caldav_sync_pending = Column(String, nullable=True)",
+        "caldav_base_url = Column(String, nullable=True)",
+        "ALTER TABLE calendar_events ADD COLUMN remote_href TEXT",
+        "ALTER TABLE calendar_events ADD COLUMN remote_etag TEXT",
+        "ALTER TABLE calendar_events ADD COLUMN caldav_sync_pending TEXT",
+        "ALTER TABLE calendars ADD COLUMN caldav_base_url TEXT",
+        "_migrate_add_caldav_sync_columns()",
+    ]:
+        assert needle in source
+
+
+def test_failed_remote_delete_leaves_tombstone_and_later_retry_cleans_up(tmp_path, monkeypatch):
+    import src.caldav_writeback as writeback
+
+    monkeypatch.setenv("DATABASE_URL", f"sqlite:///{tmp_path / 'calendar.db'}")
+    spec = importlib.util.spec_from_file_location("core.database", Path("core/database.py"))
+    dbmod = importlib.util.module_from_spec(spec)
+    monkeypatch.setitem(sys.modules, "core.database", dbmod)
+    spec.loader.exec_module(dbmod)
+
+    CalendarCal = dbmod.CalendarCal
+    CalendarDeletedEvent = dbmod.CalendarDeletedEvent
+    CalendarEvent = dbmod.CalendarEvent
+    TestingSessionLocal = dbmod.SessionLocal
+
+    session = TestingSessionLocal()
+    try:
+        cal = CalendarCal(
+            id="caldav-test",
+            owner="alice",
+            name="Remote",
+            source="caldav",
+            caldav_base_url="https://caldav.example/calendars/alice/main/",
+        )
+        ev = CalendarEvent(
+            uid="evt-delete",
+            calendar_id=cal.id,
+            summary="Delete me",
+            dtstart=datetime(2026, 6, 5, 9, 0),
+            dtend=datetime(2026, 6, 5, 10, 0),
+            remote_href="https://caldav.example/calendars/alice/main/evt-delete.ics",
+        )
+        session.add(cal)
+        session.add(ev)
+        session.commit()
+
+        tombstone = CalendarDeletedEvent(
+            uid=ev.uid,
+            owner="alice",
+            calendar_id=ev.calendar_id,
+            remote_href=ev.remote_href,
+            remote_etag=ev.remote_etag,
+            caldav_base_url=cal.caldav_base_url,
+            summary=ev.summary,
+        )
+        session.add(tombstone)
+        session.delete(ev)
+        session.commit()
+
+        assert session.query(CalendarEvent).filter_by(uid="evt-delete").first() is None
+        tombstone = session.query(CalendarDeletedEvent).filter_by(uid="evt-delete").first()
+        assert tombstone is not None
+        assert tombstone.remote_href.endswith("evt-delete.ics")
+    finally:
+        session.close()
+
+    writeback._persist_writeback_result(
+        "alice",
+        "caldav-test",
+        "evt-delete",
+        {"ok": False, "error": "temporary remote delete failure"},
+        delete=True,
+    )
+
+    session = TestingSessionLocal()
+    try:
+        tombstone = session.query(CalendarDeletedEvent).filter_by(uid="evt-delete").first()
+        assert tombstone is not None
+        assert "temporary remote delete failure" in tombstone.last_error
+    finally:
+        session.close()
+
+    writeback._persist_writeback_result(
+        "alice",
+        "caldav-test",
+        "evt-delete",
+        {"ok": True},
+        delete=True,
+    )
+
+    session = TestingSessionLocal()
+    try:
+        assert session.query(CalendarDeletedEvent).filter_by(uid="evt-delete").first() is None
+        assert session.query(CalendarEvent).filter_by(uid="evt-delete").first() is None
+    finally:
+        session.close()

tests/test_caldav_writeback.py

@@ -22,7 +22,9 @@ CAL_ID = _stable_cal_id(REMOTE_URL)
 
 
 class FakeEvent:
-    def __init__(self):
+    def __init__(self, url="https://p69-caldav.icloud.com/123/calendars/home/evt-1.ics"):
+        self.url = url
+        self.etag = '"abc123"'
         self.data = "OLD"
         self.saved = False
         self.deleted = False
@@ -39,6 +41,7 @@ class FakeCalendar:
         self.url = url
         self._existing = existing
         self.saved_ical = None
+        self.created = FakeEvent(str(url).rstrip("/") + "/created.ics")
 
     def event_by_uid(self, uid):
         if self._existing is None:
@@ -47,6 +50,7 @@ class FakeCalendar:
 
     def save_event(self, ical):
         self.saved_ical = ical
+        return self.created
 
 
 def _ev(**over):
@@ -91,6 +95,8 @@ def test_push_create_calls_save_event():
     res = push_event([cal], CAL_ID, _ev(), delete=False)
     assert res["ok"] and res.get("created")
     assert cal.saved_ical and "UID:evt-1" in cal.saved_ical
+    assert res["calendar_url"] == REMOTE_URL
+    assert res["remote_href"].endswith("/created.ics")
 
 
 def test_push_update_overwrites_existing():
@@ -100,6 +106,8 @@ def test_push_update_overwrites_existing():
     assert res["ok"] and res.get("updated")
     assert existing.saved and "SUMMARY:Moved" in existing.data
     assert cal.saved_ical is None  # used update path, not create
+    assert res["remote_href"].endswith("evt-1.ics")
+    assert res["remote_etag"] == '"abc123"'
 
 
 def test_push_delete_removes_existing():

tests/test_caldav_writeback_route.py

@@ -20,7 +20,7 @@ from sqlalchemy.pool import NullPool
 
 import core.database as cdb
 import routes.calendar_routes as croutes
-import src.caldav_writeback as wb
+import src.caldav_sync as csync
 from core.database import CalendarCal
 from routes.calendar_routes import EventCreate
 
@@ -39,11 +39,16 @@ croutes.SessionLocal = _TS
 def calls(monkeypatch):
     recorded = []
 
-    async def _fake_writeback(owner, source, cal_id, ev, *, delete=False):
-        recorded.append({"source": source, "cal_id": cal_id, "uid": ev.get("uid"), "delete": delete})
+    async def _fake_create(owner, uid):
+        recorded.append({"uid": uid, "delete": False, "action": "create"})
         return {"ok": True}
 
-    monkeypatch.setattr(wb, "writeback_event", _fake_writeback)
+    async def _fake_delete(owner, uid):
+        recorded.append({"uid": uid, "delete": True, "action": "delete"})
+        return {"ok": True}
+
+    monkeypatch.setattr(csync, "push_event_create", _fake_create)
+    monkeypatch.setattr(csync, "push_event_delete", _fake_delete)
     return recorded
 
 
@@ -77,7 +82,6 @@ async def test_create_on_caldav_calendar_pushes_to_remote(calls):
         summary="Dentist", dtstart="2026-06-10T14:00:00Z", calendar_href=cal_id))
     assert res["ok"] is True
     assert len(calls) == 1
-    assert calls[0]["source"] == "caldav" and calls[0]["cal_id"] == cal_id
     assert calls[0]["delete"] is False
 
 

tests/test_calendar_owner_scope.py

@@ -151,6 +151,7 @@ def _install_calendar_db_stub(monkeypatch):
     db = types.ModuleType("core.database")
     db.SessionLocal = MagicMock()
     db.CalendarCal = _CalendarCal
+    db.CalendarDeletedEvent = MagicMock()
     db.CalendarEvent = _CalendarEvent
     for name in [
         "Base",

tests/test_null_owner_gates.py

@@ -28,7 +28,7 @@ from unittest.mock import MagicMock
 def _null_owner_stubs(monkeypatch):
     for _stub, _attrs in (
         ("core.database", (
-            "Base", "SessionLocal", "CalendarCal", "CalendarEvent",
+            "Base", "SessionLocal", "CalendarCal", "CalendarDeletedEvent", "CalendarEvent",
             "Document", "DocumentVersion", "Session", "ChatMessage",
             "GalleryImage", "GalleryAlbum", "Note", "ScheduledTask",
             "TaskRun", "ModelEndpoint", "Webhook",