Files
hermes-agent/gateway/session_lifecycle.py
Brooklyn Nicholson 981ec5d150 fix(gateway): treat a hard-deleted session row as a dead route
_is_session_ended_in_db answered False when the row was missing from a
readable owning DB, so a session hard-deleted out of the gateway process
(CLI/TUI/desktop local delete) kept its live channel->session route: the
next inbound message resolved the deleted id and run_agent's INSERT OR
IGNORE re-created the row with its old content — the deleted conversation
resurrected (#42422). A missing row is now the same verdict as an ended
one: the stale-route self-heal drops the entry, recovery finds nothing,
and the peer mints a fresh session. DB errors still answer False.
2026-09-26 22:30:35 -05:00

248 lines
11 KiB
Python

"""SessionStore explicit suspension, crash-recovery markers, pruning and shared clock/id helpers."""
from __future__ import annotations
import logging
import os
import time
import uuid
from datetime import datetime, timedelta, timezone
from typing import TYPE_CHECKING, Optional
from hermes_state_ids import new_session_id
if TYPE_CHECKING:
from gateway.session import SessionEntry, SessionSource
# Log-record parity with the origin module.
logger = logging.getLogger("gateway.session")
def _now() -> datetime:
"""Return the current local time."""
return datetime.now()
def _new_session_id(now: datetime) -> str:
return new_session_id(now, hex_len=8)
def _iso(dt: Optional[datetime]) -> Optional[str]:
return dt.isoformat() if dt else None
def _parse_iso(value) -> Optional[datetime]:
"""``datetime.fromisoformat`` that returns None for empty/malformed input."""
if not value:
return None
try:
return datetime.fromisoformat(value)
except (TypeError, ValueError):
return None
# Auto-continue freshness window (1 hour) after the ``resume_pending`` mark; ``gateway/run.py``
# bridges config.yaml ``agent.gateway_auto_continue_freshness`` into the env var at startup.
_AUTO_CONTINUE_FRESHNESS_SECS_DEFAULT = 60 * 60
def auto_continue_freshness_window() -> float:
"""Resume-scheduler freshness window; stale automation never discards the transcript."""
raw = os.environ.get("HERMES_AUTO_CONTINUE_FRESHNESS")
try:
return float(raw) if raw else float(_AUTO_CONTINUE_FRESHNESS_SECS_DEFAULT)
except (TypeError, ValueError):
return float(_AUTO_CONTINUE_FRESHNESS_SECS_DEFAULT)
class SessionLifecycleMixin:
"""SessionStore explicit boundaries and crash-recovery markers."""
def _is_session_ended_in_db(self, session_id: str) -> bool:
"""True iff state.db says the session is gone: ended (non-null end_reason) or hard-deleted
(no row in a readable owning DB). No DB or a DB error -> False (same failure mode as
``_prune_stale_sessions_locked``). Lets routing self-heal a session finalized or deleted
while the gateway stays alive. Store resolved from the owning profile.
Used by ``get_or_create_session`` to self-heal at routing time: ``_prune_stale_sessions_locked``
only runs at startup, so a session ended in the DB while the gateway stays alive (any path that
finalizes the row without clearing sessions.json) would otherwise be reused as a live routing key
and silently swallow every subsequent message until the next restart (#54878 — the live-gateway
variant of #52804/FM9). A hard delete is the same shape one step further: the row is GONE, not
merely ended, and reusing the route makes run_agent's INSERT OR IGNORE resurrect the deleted
session with its old id (#42422) — so a missing row is treated exactly like an ended one. DB
errors are non-fatal — never block routing on a failed lookup.
The store is resolved from the row's owning profile rather than the ambient scope: an unscoped
background writer keeps its own copy of the same session, and comparing against that copy reports a
live session as ended (#66887).
"""
db = self._db_for_session_id(session_id)
if not db or not session_id:
return False
try:
row = db.get_session(session_id)
except Exception:
return False
return row is None or row.get("end_reason") is not None
def _route_reset_reason(self, entry: SessionEntry) -> Optional[str]:
"""Only explicit suspension replaces a routed conversation; time never does."""
return "suspended" if entry.suspended else None
def _update_entry(self, session_key: str, mutate) -> bool:
"""Apply ``mutate(entry)`` under ``_lock`` and full-save; False when the entry is missing
or *mutate* returned False (nothing to persist)."""
with self._lock:
entry = self._entry_locked(session_key)
if entry is None or mutate(entry) is False:
return False
self._save()
return True
def _update_all_entries_locked(self, mutate) -> int:
"""Apply ``mutate(entry) -> bool`` to every entry under ``_lock``; save once if any
returned True. Returns the count that did."""
with self._lock:
self._ensure_loaded_locked()
changed = sum(1 for entry in self._entries.values() if mutate(entry))
if changed:
self._save()
return changed
def suspend_session(self, session_key: str) -> bool:
"""Mark a session suspended so it auto-resets on next access (/stop). True if it existed.
Used by ``/stop`` to prevent stuck sessions from being resumed after a gateway restart (#7536).
"""
return self._update_entry(session_key, lambda e: setattr(e, "suspended", True))
def _set_turn_marker_locked(self, session_key: str, entry: SessionEntry, token, started_at) -> None:
"""Persist the active-turn pair BEFORE publishing it in memory, so a failed write can
neither leak an unowned token nor drop a live one. Lock held."""
candidate = entry.to_dict()
candidate["active_turn_token"] = token
candidate["active_turn_started_at"] = _iso(started_at)
touched = _now() if started_at is not None else None
if touched is not None:
# Keeps the legacy 120s startup heuristic working for an older binary during a rolling
# downgrade/upgrade window.
candidate["updated_at"] = touched.isoformat()
self._save_entry(session_key, entry_data=candidate, lock_held=True)
entry.active_turn_token = token
entry.active_turn_started_at = started_at
if touched is not None:
entry.updated_at = touched
def mark_turn_active(self, session_key: str) -> Optional[str]:
"""Persist exact ownership of the running agent turn; returns the opaque token for
:meth:`clear_turn_active`. Re-marking replaces the previous token so a stale asynchronous
unwind cannot clear a newer turn."""
token = uuid.uuid4().hex
with self._lock:
entry = self._entry_locked(session_key)
if entry is None:
return None
# Aware UTC, unlike the local wall clock elsewhere: the next process compares it with
# epoch transcript timestamps and may run in another zone (DST, container vs unit TZ).
self._set_turn_marker_locked(session_key, entry, token, datetime.now(timezone.utc))
return token
def clear_turn_active(self, session_key: str, token: str) -> bool:
"""Compare-and-swap clear an active-turn marker; ``False`` when the entry disappeared or a
newer turn owns it."""
with self._lock:
entry = self._entry_locked(session_key)
if entry is None or entry.active_turn_token != token:
return False
self._set_turn_marker_locked(session_key, entry, None, None)
return True
def recover_interrupted_turns(self, max_age_seconds: int = 60 * 60) -> int:
"""Promote crash-left turn markers into ``resume_pending`` (unclean startup only).
Old/invalid markers are cleared without resuming; suspended sessions are never re-armed.
Returns the number of newly promoted sessions."""
now, epoch_now = _now(), time.time()
promoted = 0
def _promote(entry: SessionEntry) -> bool:
nonlocal promoted
if not entry.active_turn_token:
return False
started_at = entry.active_turn_started_at
# Epoch arithmetic: a pre-upgrade naive marker reads as local time, an aware one exactly.
marker_is_stale = started_at is None or (
max_age_seconds > 0 and epoch_now - started_at.timestamp() > max_age_seconds
)
if not marker_is_stale and not entry.suspended:
if entry.resume_pending:
# A drain-timeout marker is more specific; keep it.
if entry.last_resume_marked_at is None:
entry.last_resume_marked_at = now
else:
entry.resume_pending = True
entry.resume_reason = "restart_interrupted"
entry.last_resume_marked_at = now # freshness starts at discovery
promoted += 1
entry.active_turn_token = None
entry.active_turn_started_at = None
return True
self._update_all_entries_locked(_promote)
return promoted
def discard_active_turn_markers(self) -> int:
"""Clear orphan turn markers after a verified clean shutdown."""
def _discard(entry: SessionEntry) -> bool:
if not entry.active_turn_token and entry.active_turn_started_at is None:
return False
entry.active_turn_token = None
entry.active_turn_started_at = None
return True
return self._update_all_entries_locked(_discard)
def mark_resume_pending(self, session_key: str, reason: str = "restart_timeout") -> bool:
"""Mark a session resumable after a restart interruption (keeps the session_id/transcript,
unlike ``suspend_session``). True if marked."""
def _apply(entry: SessionEntry):
if entry.suspended: # never override an explicit ``suspended`` (hard forced-wipe)
return False
entry.resume_pending = True
entry.resume_reason = reason
entry.last_resume_marked_at = _now()
return self._update_entry(session_key, _apply)
def clear_resume_pending(self, session_key: str) -> bool:
"""Clear the resume-pending flag after a successful resumed turn; True if cleared."""
def _apply(entry: SessionEntry):
if not entry.resume_pending:
return False
entry.resume_pending = False
entry.resume_reason = None
entry.last_resume_marked_at = None
return self._update_entry(session_key, _apply)
def prune_old_entries(self, max_age_days: int) -> int:
"""Drop routing entries idle (by ``updated_at``) for more than max_age_days; suspended
entries and entries with active background processes are kept. Only the key -> session_id
mapping is dropped (the transcript stays). ``max_age_days <= 0`` disables. Returns count."""
if max_age_days is None or max_age_days <= 0:
return 0
cutoff = _now() - timedelta(days=max_age_days)
with self._lock:
self._ensure_loaded_locked()
removed_keys = [
key for key, entry in list(self._entries.items())
if not entry.suspended
# The callback is keyed by session_key, NOT session_id.
and not self._has_active_processes_safe(entry.session_key, context="prune")
and entry.updated_at < cutoff
]
for key in removed_keys:
self._entries.pop(key, None)
if removed_keys:
self._save()
if removed_keys:
logger.info("SessionStore pruned %d entries older than %d days",
len(removed_keys), max_age_days)
return len(removed_keys)