"""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, session_key: Optional[str] = None) -> 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). Pass *session_key* when the owning key is known but the id may have left the routing index: after the self-heal re-homes the key, the id has no owner and would resolve to the launch store, which never holds a routed profile's rows (#118862). """ db = self._db_for_key(session_key) if session_key else 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)