After a prolonged outage the in-process network-error ladder escalates to
fatal and GatewayRunner._platform_reconnect_watcher rebuilds a fresh adapter
that reconnects through the bootstrap path. That path called
start_polling(drop_pending_updates=True), discarding every update Telegram
queued during the outage — all messages sent while the bot was down were
silently lost. The in-process ladder and 409-conflict handler already passed
drop_pending_updates=False; only bootstrap did not distinguish a cold first
boot from a reconnect.
Thread an is_reconnect signal from the watcher through
_connect_adapter_with_timeout into adapter.connect(). The base
BasePlatformAdapter.connect() gains a keyword-only is_reconnect=False so every
adapter inherits a tolerant signature (no per-platform breakage when the
runner forwards the kwarg). Telegram translates is_reconnect into
drop_pending_updates=not is_reconnect on both the polling and webhook bootstrap
calls. Cold boot still drops the stale queue; a watcher reconnect preserves it.
Fixes#46621.
Co-authored-by: annguyenNous <annguyen@nousresearch.com>
Co-authored-by: kyssta-exe <kyssta-exe@users.noreply.github.com>
Co-authored-by: Kewe63 <Kewe63@users.noreply.github.com>
During gateway shutdown, a message arriving while
cancel_background_tasks is mid-await (inside asyncio.gather) spawns
a fresh _process_message_background task via handle_message and adds
it to self._background_tasks. The original implementation's
_background_tasks.clear() at the end of cancel_background_tasks
dropped the reference; the task ran untracked against a disconnecting
adapter, logged send-failures, and lingered until it completed on
its own.
Fix: wrap the cancel+gather in a bounded loop (MAX_DRAIN_ROUNDS=5).
If new tasks appeared during the gather, cancel them in the next
round. The .clear() at the end is preserved as a safety net for
any task that appeared after MAX_DRAIN_ROUNDS — but in practice the
drain stabilizes in 1-2 rounds.
Tests: tests/gateway/test_cancel_background_drain.py — 3 cases.
- test_cancel_background_tasks_drains_late_arrivals: spawn M1, start
cancel, inject M2 during M1's shielded cleanup, verify M2 is
cancelled.
- test_cancel_background_tasks_handles_no_tasks: no-op path still
terminates cleanly.
- test_cancel_background_tasks_bounded_rounds: baseline — single
task cancels in one round, loop terminates.
Regression-guard validated: against the unpatched implementation,
the late-arrival test fails with exactly the expected message
('task leaked'). With the fix it passes.
Blast radius is shutdown-only; the audit classified this as MED.
Shipping because the fix is small and the hygiene is worth it.
While investigating the audit's other MEDs (busy-handler double-ack,
Discord ExecApprovalView double-resolve, UpdatePromptView
double-resolve), I verified all three were false positives — the
check-and-set patterns have no await between them, so they're
atomic on single-threaded asyncio. No fix needed for those.
