""" Session management for the gateway. Handles: - Session context tracking (where messages come from) - Session storage (conversations persisted to disk) - Reset policy evaluation (when to start fresh) - Dynamic system prompt injection (agent knows its context) """ import hashlib import logging import os import json import re import uuid from pathlib import Path from datetime import datetime, timedelta from dataclasses import dataclass, field from typing import Dict, List, Optional, Any logger = logging.getLogger(__name__) # --------------------------------------------------------------------------- # PII redaction helpers # --------------------------------------------------------------------------- _PHONE_RE = re.compile(r"^\+?\d[\d\-\s]{6,}$") def _hash_id(value: str) -> str: """Deterministic 12-char hex hash of an identifier.""" return hashlib.sha256(value.encode("utf-8")).hexdigest()[:12] def _hash_sender_id(value: str) -> str: """Hash a sender ID to ``user_<12hex>``.""" return f"user_{_hash_id(value)}" def _hash_chat_id(value: str) -> str: """Hash the numeric portion of a chat ID, preserving platform prefix. ``telegram:12345`` → ``telegram:`` ``12345`` → ```` """ colon = value.find(":") if colon > 0: prefix = value[:colon] return f"{prefix}:{_hash_id(value[colon + 1:])}" return _hash_id(value) def _looks_like_phone(value: str) -> bool: """Return True if *value* looks like a phone number (E.164 or similar).""" return bool(_PHONE_RE.match(value.strip())) from .config import ( Platform, GatewayConfig, SessionResetPolicy, HomeChannel, ) @dataclass class SessionSource: """ Describes where a message originated from. This information is used to: 1. Route responses back to the right place 2. Inject context into the system prompt 3. Track origin for cron job delivery """ platform: Platform chat_id: str chat_name: Optional[str] = None chat_type: str = "dm" # "dm", "group", "channel", "thread" user_id: Optional[str] = None user_name: Optional[str] = None thread_id: Optional[str] = None # For forum topics, Discord threads, etc. chat_topic: Optional[str] = None # Channel topic/description (Discord, Slack) user_id_alt: Optional[str] = None # Signal UUID (alternative to phone number) chat_id_alt: Optional[str] = None # Signal group internal ID @property def description(self) -> str: """Human-readable description of the source.""" if self.platform == Platform.LOCAL: return "CLI terminal" parts = [] if self.chat_type == "dm": parts.append(f"DM with {self.user_name or self.user_id or 'user'}") elif self.chat_type == "group": parts.append(f"group: {self.chat_name or self.chat_id}") elif self.chat_type == "channel": parts.append(f"channel: {self.chat_name or self.chat_id}") else: parts.append(self.chat_name or self.chat_id) if self.thread_id: parts.append(f"thread: {self.thread_id}") return ", ".join(parts) def to_dict(self) -> Dict[str, Any]: d = { "platform": self.platform.value, "chat_id": self.chat_id, "chat_name": self.chat_name, "chat_type": self.chat_type, "user_id": self.user_id, "user_name": self.user_name, "thread_id": self.thread_id, "chat_topic": self.chat_topic, } if self.user_id_alt: d["user_id_alt"] = self.user_id_alt if self.chat_id_alt: d["chat_id_alt"] = self.chat_id_alt return d @classmethod def from_dict(cls, data: Dict[str, Any]) -> "SessionSource": return cls( platform=Platform(data["platform"]), chat_id=str(data["chat_id"]), chat_name=data.get("chat_name"), chat_type=data.get("chat_type", "dm"), user_id=data.get("user_id"), user_name=data.get("user_name"), thread_id=data.get("thread_id"), chat_topic=data.get("chat_topic"), user_id_alt=data.get("user_id_alt"), chat_id_alt=data.get("chat_id_alt"), ) @classmethod def local_cli(cls) -> "SessionSource": """Create a source representing the local CLI.""" return cls( platform=Platform.LOCAL, chat_id="cli", chat_name="CLI terminal", chat_type="dm", ) @dataclass class SessionContext: """ Full context for a session, used for dynamic system prompt injection. The agent receives this information to understand: - Where messages are coming from - What platforms are available - Where it can deliver scheduled task outputs """ source: SessionSource connected_platforms: List[Platform] home_channels: Dict[Platform, HomeChannel] # Session metadata session_key: str = "" session_id: str = "" created_at: Optional[datetime] = None updated_at: Optional[datetime] = None def to_dict(self) -> Dict[str, Any]: return { "source": self.source.to_dict(), "connected_platforms": [p.value for p in self.connected_platforms], "home_channels": { p.value: hc.to_dict() for p, hc in self.home_channels.items() }, "session_key": self.session_key, "session_id": self.session_id, "created_at": self.created_at.isoformat() if self.created_at else None, "updated_at": self.updated_at.isoformat() if self.updated_at else None, } _PII_SAFE_PLATFORMS = frozenset({ Platform.WHATSAPP, Platform.SIGNAL, Platform.TELEGRAM, }) """Platforms where user IDs can be safely redacted (no in-message mention system that requires raw IDs). Discord is excluded because mentions use ``<@user_id>`` and the LLM needs the real ID to tag users.""" def build_session_context_prompt( context: SessionContext, *, redact_pii: bool = False, ) -> str: """ Build the dynamic system prompt section that tells the agent about its context. This is injected into the system prompt so the agent knows: - Where messages are coming from - What platforms are connected - Where it can deliver scheduled task outputs When *redact_pii* is True **and** the source platform is in ``_PII_SAFE_PLATFORMS``, phone numbers are stripped and user/chat IDs are replaced with deterministic hashes before being sent to the LLM. Platforms like Discord are excluded because mentions need real IDs. Routing still uses the original values (they stay in SessionSource). """ # Only apply redaction on platforms where IDs aren't needed for mentions redact_pii = redact_pii and context.source.platform in _PII_SAFE_PLATFORMS lines = [ "## Current Session Context", "", ] # Source info platform_name = context.source.platform.value.title() if context.source.platform == Platform.LOCAL: lines.append(f"**Source:** {platform_name} (the machine running this agent)") else: # Build a description that respects PII redaction src = context.source if redact_pii: # Build a safe description without raw IDs _uname = src.user_name or ( _hash_sender_id(src.user_id) if src.user_id else "user" ) _cname = src.chat_name or _hash_chat_id(src.chat_id) if src.chat_type == "dm": desc = f"DM with {_uname}" elif src.chat_type == "group": desc = f"group: {_cname}" elif src.chat_type == "channel": desc = f"channel: {_cname}" else: desc = _cname else: desc = src.description lines.append(f"**Source:** {platform_name} ({desc})") # Channel topic (if available - provides context about the channel's purpose) if context.source.chat_topic: lines.append(f"**Channel Topic:** {context.source.chat_topic}") # User identity (especially useful for WhatsApp where multiple people DM) if context.source.user_name: lines.append(f"**User:** {context.source.user_name}") elif context.source.user_id: uid = context.source.user_id if redact_pii: uid = _hash_sender_id(uid) lines.append(f"**User ID:** {uid}") # Platform-specific behavioral notes if context.source.platform == Platform.SLACK: lines.append("") lines.append( "**Platform notes:** You are running inside Slack. " "You do NOT have access to Slack-specific APIs — you cannot search " "channel history, pin/unpin messages, manage channels, or list users. " "Do not promise to perform these actions. If the user asks, explain " "that you can only read messages sent directly to you and respond." ) elif context.source.platform == Platform.DISCORD: lines.append("") lines.append( "**Platform notes:** You are running inside Discord. " "You do NOT have access to Discord-specific APIs — you cannot search " "channel history, pin messages, manage roles, or list server members. " "Do not promise to perform these actions. If the user asks, explain " "that you can only read messages sent directly to you and respond." ) # Connected platforms platforms_list = ["local (files on this machine)"] for p in context.connected_platforms: if p != Platform.LOCAL: platforms_list.append(f"{p.value}: Connected ✓") lines.append(f"**Connected Platforms:** {', '.join(platforms_list)}") # Home channels if context.home_channels: lines.append("") lines.append("**Home Channels (default destinations):**") for platform, home in context.home_channels.items(): hc_id = _hash_chat_id(home.chat_id) if redact_pii else home.chat_id lines.append(f" - {platform.value}: {home.name} (ID: {hc_id})") # Delivery options for scheduled tasks lines.append("") lines.append("**Delivery options for scheduled tasks:**") # Origin delivery if context.source.platform == Platform.LOCAL: lines.append("- `\"origin\"` → Local output (saved to files)") else: _origin_label = context.source.chat_name or ( _hash_chat_id(context.source.chat_id) if redact_pii else context.source.chat_id ) lines.append(f"- `\"origin\"` → Back to this chat ({_origin_label})") # Local always available lines.append("- `\"local\"` → Save to local files only (~/.hermes/cron/output/)") # Platform home channels for platform, home in context.home_channels.items(): lines.append(f"- `\"{platform.value}\"` → Home channel ({home.name})") # Note about explicit targeting lines.append("") lines.append("*For explicit targeting, use `\"platform:chat_id\"` format if the user provides a specific chat ID.*") return "\n".join(lines) @dataclass class SessionEntry: """ Entry in the session store. Maps a session key to its current session ID and metadata. """ session_key: str session_id: str created_at: datetime updated_at: datetime # Origin metadata for delivery routing origin: Optional[SessionSource] = None # Display metadata display_name: Optional[str] = None platform: Optional[Platform] = None chat_type: str = "dm" # Token tracking input_tokens: int = 0 output_tokens: int = 0 total_tokens: int = 0 # Last API-reported prompt tokens (for accurate compression pre-check) last_prompt_tokens: int = 0 # Set when a session was created because the previous one expired; # consumed once by the message handler to inject a notice into context was_auto_reset: bool = False def to_dict(self) -> Dict[str, Any]: result = { "session_key": self.session_key, "session_id": self.session_id, "created_at": self.created_at.isoformat(), "updated_at": self.updated_at.isoformat(), "display_name": self.display_name, "platform": self.platform.value if self.platform else None, "chat_type": self.chat_type, "input_tokens": self.input_tokens, "output_tokens": self.output_tokens, "total_tokens": self.total_tokens, "last_prompt_tokens": self.last_prompt_tokens, } if self.origin: result["origin"] = self.origin.to_dict() return result @classmethod def from_dict(cls, data: Dict[str, Any]) -> "SessionEntry": origin = None if "origin" in data and data["origin"]: origin = SessionSource.from_dict(data["origin"]) platform = None if data.get("platform"): try: platform = Platform(data["platform"]) except ValueError as e: logger.debug("Unknown platform value %r: %s", data["platform"], e) return cls( session_key=data["session_key"], session_id=data["session_id"], created_at=datetime.fromisoformat(data["created_at"]), updated_at=datetime.fromisoformat(data["updated_at"]), origin=origin, display_name=data.get("display_name"), platform=platform, chat_type=data.get("chat_type", "dm"), input_tokens=data.get("input_tokens", 0), output_tokens=data.get("output_tokens", 0), total_tokens=data.get("total_tokens", 0), last_prompt_tokens=data.get("last_prompt_tokens", 0), ) def build_session_key(source: SessionSource, group_sessions_per_user: bool = True) -> str: """Build a deterministic session key from a message source. This is the single source of truth for session key construction. DM rules: - DMs include chat_id when present, so each private conversation is isolated. - thread_id further differentiates threaded DMs within the same DM chat. - Without chat_id, thread_id is used as a best-effort fallback. - Without thread_id or chat_id, DMs share a single session. Group/channel rules: - chat_id identifies the parent group/channel. - user_id/user_id_alt isolates participants within that parent chat when available when ``group_sessions_per_user`` is enabled. - thread_id differentiates threads within that parent chat. - Without participant identifiers, or when isolation is disabled, messages fall back to one shared session per chat. - Without identifiers, messages fall back to one session per platform/chat_type. """ platform = source.platform.value if source.chat_type == "dm": if source.chat_id: if source.thread_id: return f"agent:main:{platform}:dm:{source.chat_id}:{source.thread_id}" return f"agent:main:{platform}:dm:{source.chat_id}" if source.thread_id: return f"agent:main:{platform}:dm:{source.thread_id}" return f"agent:main:{platform}:dm" participant_id = source.user_id_alt or source.user_id key_parts = ["agent:main", platform, source.chat_type] if source.chat_id: key_parts.append(source.chat_id) if source.thread_id: key_parts.append(source.thread_id) if group_sessions_per_user and participant_id: key_parts.append(str(participant_id)) return ":".join(key_parts) class SessionStore: """ Manages session storage and retrieval. Uses SQLite (via SessionDB) for session metadata and message transcripts. Falls back to legacy JSONL files if SQLite is unavailable. """ def __init__(self, sessions_dir: Path, config: GatewayConfig, has_active_processes_fn=None, on_auto_reset=None): self.sessions_dir = sessions_dir self.config = config self._entries: Dict[str, SessionEntry] = {} self._loaded = False self._has_active_processes_fn = has_active_processes_fn # on_auto_reset is deprecated — memory flush now runs proactively # via the background session expiry watcher in GatewayRunner. self._pre_flushed_sessions: set = set() # session_ids already flushed by watcher # Initialize SQLite session database self._db = None try: from hermes_state import SessionDB self._db = SessionDB() except Exception as e: print(f"[gateway] Warning: SQLite session store unavailable, falling back to JSONL: {e}") def _ensure_loaded(self) -> None: """Load sessions index from disk if not already loaded.""" if self._loaded: return self.sessions_dir.mkdir(parents=True, exist_ok=True) sessions_file = self.sessions_dir / "sessions.json" if sessions_file.exists(): try: with open(sessions_file, "r", encoding="utf-8") as f: data = json.load(f) for key, entry_data in data.items(): try: self._entries[key] = SessionEntry.from_dict(entry_data) except (ValueError, KeyError): # Skip entries with unknown/removed platform values continue except Exception as e: print(f"[gateway] Warning: Failed to load sessions: {e}") self._loaded = True def _save(self) -> None: """Save sessions index to disk (kept for session key -> ID mapping).""" import tempfile self.sessions_dir.mkdir(parents=True, exist_ok=True) sessions_file = self.sessions_dir / "sessions.json" data = {key: entry.to_dict() for key, entry in self._entries.items()} fd, tmp_path = tempfile.mkstemp( dir=str(self.sessions_dir), suffix=".tmp", prefix=".sessions_" ) try: with os.fdopen(fd, "w", encoding="utf-8") as f: json.dump(data, f, indent=2) f.flush() os.fsync(f.fileno()) os.replace(tmp_path, sessions_file) except BaseException: try: os.unlink(tmp_path) except OSError as e: logger.debug("Could not remove temp file %s: %s", tmp_path, e) raise def _generate_session_key(self, source: SessionSource) -> str: """Generate a session key from a source.""" return build_session_key( source, group_sessions_per_user=getattr(self.config, "group_sessions_per_user", True), ) def _is_session_expired(self, entry: SessionEntry) -> bool: """Check if a session has expired based on its reset policy. Works from the entry alone — no SessionSource needed. Used by the background expiry watcher to proactively flush memories. Sessions with active background processes are never considered expired. """ if self._has_active_processes_fn: if self._has_active_processes_fn(entry.session_key): return False policy = self.config.get_reset_policy( platform=entry.platform, session_type=entry.chat_type, ) if policy.mode == "none": return False now = datetime.now() if policy.mode in ("idle", "both"): idle_deadline = entry.updated_at + timedelta(minutes=policy.idle_minutes) if now > idle_deadline: return True if policy.mode in ("daily", "both"): today_reset = now.replace( hour=policy.at_hour, minute=0, second=0, microsecond=0, ) if now.hour < policy.at_hour: today_reset -= timedelta(days=1) if entry.updated_at < today_reset: return True return False def _should_reset(self, entry: SessionEntry, source: SessionSource) -> bool: """ Check if a session should be reset based on policy. Sessions with active background processes are never reset. """ if self._has_active_processes_fn: session_key = self._generate_session_key(source) if self._has_active_processes_fn(session_key): return False policy = self.config.get_reset_policy( platform=source.platform, session_type=source.chat_type ) if policy.mode == "none": return False now = datetime.now() if policy.mode in ("idle", "both"): idle_deadline = entry.updated_at + timedelta(minutes=policy.idle_minutes) if now > idle_deadline: return True if policy.mode in ("daily", "both"): today_reset = now.replace( hour=policy.at_hour, minute=0, second=0, microsecond=0 ) if now.hour < policy.at_hour: today_reset -= timedelta(days=1) if entry.updated_at < today_reset: return True return False def has_any_sessions(self) -> bool: """Check if any sessions have ever been created (across all platforms). Uses the SQLite database as the source of truth because it preserves historical session records (ended sessions still count). The in-memory ``_entries`` dict replaces entries on reset, so ``len(_entries)`` would stay at 1 for single-platform users — which is the bug this fixes. The current session is already in the DB by the time this is called (get_or_create_session runs first), so we check ``> 1``. """ if self._db: try: return self._db.session_count() > 1 except Exception: pass # fall through to heuristic # Fallback: check if sessions.json was loaded with existing data. # This covers the rare case where the DB is unavailable. self._ensure_loaded() return len(self._entries) > 1 def get_or_create_session( self, source: SessionSource, force_new: bool = False ) -> SessionEntry: """ Get an existing session or create a new one. Evaluates reset policy to determine if the existing session is stale. Creates a session record in SQLite when a new session starts. """ self._ensure_loaded() session_key = self._generate_session_key(source) now = datetime.now() if session_key in self._entries and not force_new: entry = self._entries[session_key] if not self._should_reset(entry, source): entry.updated_at = now self._save() return entry else: # Session is being auto-reset. The background expiry watcher # should have already flushed memories proactively; discard # the marker so it doesn't accumulate. was_auto_reset = True self._pre_flushed_sessions.discard(entry.session_id) if self._db: try: self._db.end_session(entry.session_id, "session_reset") except Exception as e: logger.debug("Session DB operation failed: %s", e) else: was_auto_reset = False # Create new session session_id = f"{now.strftime('%Y%m%d_%H%M%S')}_{uuid.uuid4().hex[:8]}" entry = SessionEntry( session_key=session_key, session_id=session_id, created_at=now, updated_at=now, origin=source, display_name=source.chat_name, platform=source.platform, chat_type=source.chat_type, was_auto_reset=was_auto_reset, ) self._entries[session_key] = entry self._save() # Create session in SQLite if self._db: try: self._db.create_session( session_id=session_id, source=source.platform.value, user_id=source.user_id, ) except Exception as e: print(f"[gateway] Warning: Failed to create SQLite session: {e}") return entry def update_session( self, session_key: str, input_tokens: int = 0, output_tokens: int = 0, last_prompt_tokens: int = None, model: str = None, ) -> None: """Update a session's metadata after an interaction.""" self._ensure_loaded() if session_key in self._entries: entry = self._entries[session_key] entry.updated_at = datetime.now() entry.input_tokens += input_tokens entry.output_tokens += output_tokens if last_prompt_tokens is not None: entry.last_prompt_tokens = last_prompt_tokens entry.total_tokens = entry.input_tokens + entry.output_tokens self._save() if self._db: try: self._db.update_token_counts( entry.session_id, input_tokens, output_tokens, model=model, ) except Exception as e: logger.debug("Session DB operation failed: %s", e) def reset_session(self, session_key: str) -> Optional[SessionEntry]: """Force reset a session, creating a new session ID.""" self._ensure_loaded() if session_key not in self._entries: return None old_entry = self._entries[session_key] # End old session in SQLite if self._db: try: self._db.end_session(old_entry.session_id, "session_reset") except Exception as e: logger.debug("Session DB operation failed: %s", e) now = datetime.now() session_id = f"{now.strftime('%Y%m%d_%H%M%S')}_{uuid.uuid4().hex[:8]}" new_entry = SessionEntry( session_key=session_key, session_id=session_id, created_at=now, updated_at=now, origin=old_entry.origin, display_name=old_entry.display_name, platform=old_entry.platform, chat_type=old_entry.chat_type, ) self._entries[session_key] = new_entry self._save() # Create new session in SQLite if self._db: try: self._db.create_session( session_id=session_id, source=old_entry.platform.value if old_entry.platform else "unknown", user_id=old_entry.origin.user_id if old_entry.origin else None, ) except Exception as e: logger.debug("Session DB operation failed: %s", e) return new_entry def switch_session(self, session_key: str, target_session_id: str) -> Optional[SessionEntry]: """Switch a session key to point at an existing session ID. Used by ``/resume`` to restore a previously-named session. Ends the current session in SQLite (like reset), but instead of generating a fresh session ID, re-uses ``target_session_id`` so the old transcript is loaded on the next message. """ self._ensure_loaded() if session_key not in self._entries: return None old_entry = self._entries[session_key] # Don't switch if already on that session if old_entry.session_id == target_session_id: return old_entry # End the current session in SQLite if self._db: try: self._db.end_session(old_entry.session_id, "session_switch") except Exception as e: logger.debug("Session DB end_session failed: %s", e) now = datetime.now() new_entry = SessionEntry( session_key=session_key, session_id=target_session_id, created_at=now, updated_at=now, origin=old_entry.origin, display_name=old_entry.display_name, platform=old_entry.platform, chat_type=old_entry.chat_type, ) self._entries[session_key] = new_entry self._save() return new_entry def list_sessions(self, active_minutes: Optional[int] = None) -> List[SessionEntry]: """List all sessions, optionally filtered by activity.""" self._ensure_loaded() entries = list(self._entries.values()) if active_minutes is not None: cutoff = datetime.now() - timedelta(minutes=active_minutes) entries = [e for e in entries if e.updated_at >= cutoff] entries.sort(key=lambda e: e.updated_at, reverse=True) return entries def get_transcript_path(self, session_id: str) -> Path: """Get the path to a session's legacy transcript file.""" return self.sessions_dir / f"{session_id}.jsonl" def append_to_transcript(self, session_id: str, message: Dict[str, Any], skip_db: bool = False) -> None: """Append a message to a session's transcript (SQLite + legacy JSONL). Args: skip_db: When True, only write to JSONL and skip the SQLite write. Used when the agent already persisted messages to SQLite via its own _flush_messages_to_session_db(), preventing the duplicate-write bug (#860). """ # Write to SQLite (unless the agent already handled it) if self._db and not skip_db: try: self._db.append_message( session_id=session_id, role=message.get("role", "unknown"), content=message.get("content"), tool_name=message.get("tool_name"), tool_calls=message.get("tool_calls"), tool_call_id=message.get("tool_call_id"), ) except Exception as e: logger.debug("Session DB operation failed: %s", e) # Also write legacy JSONL (keeps existing tooling working during transition) transcript_path = self.get_transcript_path(session_id) with open(transcript_path, "a", encoding="utf-8") as f: f.write(json.dumps(message, ensure_ascii=False) + "\n") def rewrite_transcript(self, session_id: str, messages: List[Dict[str, Any]]) -> None: """Replace the entire transcript for a session with new messages. Used by /retry, /undo, and /compress to persist modified conversation history. Rewrites both SQLite and legacy JSONL storage. """ # SQLite: clear old messages and re-insert if self._db: try: self._db.clear_messages(session_id) for msg in messages: self._db.append_message( session_id=session_id, role=msg.get("role", "unknown"), content=msg.get("content"), tool_name=msg.get("tool_name"), tool_calls=msg.get("tool_calls"), tool_call_id=msg.get("tool_call_id"), ) except Exception as e: logger.debug("Failed to rewrite transcript in DB: %s", e) # JSONL: overwrite the file transcript_path = self.get_transcript_path(session_id) with open(transcript_path, "w", encoding="utf-8") as f: for msg in messages: f.write(json.dumps(msg, ensure_ascii=False) + "\n") def load_transcript(self, session_id: str) -> List[Dict[str, Any]]: """Load all messages from a session's transcript.""" # Try SQLite first if self._db: try: messages = self._db.get_messages_as_conversation(session_id) if messages: return messages except Exception as e: logger.debug("Could not load messages from DB: %s", e) # Fall back to legacy JSONL transcript_path = self.get_transcript_path(session_id) if not transcript_path.exists(): return [] messages = [] with open(transcript_path, "r", encoding="utf-8") as f: for line in f: line = line.strip() if line: messages.append(json.loads(line)) return messages def build_session_context( source: SessionSource, config: GatewayConfig, session_entry: Optional[SessionEntry] = None ) -> SessionContext: """ Build a full session context from a source and config. This is used to inject context into the agent's system prompt. """ connected = config.get_connected_platforms() home_channels = {} for platform in connected: home = config.get_home_channel(platform) if home: home_channels[platform] = home context = SessionContext( source=source, connected_platforms=connected, home_channels=home_channels, ) if session_entry: context.session_key = session_entry.session_key context.session_id = session_entry.session_id context.created_at = session_entry.created_at context.updated_at = session_entry.updated_at return context