feat(08-03): push notification backend — DB model, migration, API router, VAPID setup
- Add PushSubscription ORM model with unique(user_id, endpoint) constraint - Add Alembic migration 012 for push_subscriptions table - Add push router (subscribe, unsubscribe, send) in shared/api/push.py - Mount push router in gateway/main.py - Add pywebpush to gateway dependencies for server-side VAPID delivery - Wire push trigger into WebSocket handler (fires when client disconnects mid-stream) - Add VAPID keys to .env / .env.example - Add push/install i18n keys in en/es/pt message files
This commit is contained in:
@@ -27,6 +27,11 @@ Design notes:
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- DB access uses configure_rls_hook + current_tenant_id context var per project pattern
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- WebSocket is a long-lived connection; each message/response cycle is synchronous
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within the connection but non-blocking for other connections
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Push notifications:
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- Connected users are tracked in _connected_users (in-memory dict)
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- When the WebSocket send for "done" raises (client disconnected mid-stream),
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a push notification is fired so the user sees the response on their device.
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"""
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from __future__ import annotations
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@@ -40,7 +45,7 @@ from typing import Any
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import redis.asyncio as aioredis
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from fastapi import APIRouter, WebSocket, WebSocketDisconnect
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from sqlalchemy import select, text
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from sqlalchemy import delete, select, text
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from orchestrator.agents.builder import build_messages_with_memory, build_system_prompt
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from orchestrator.agents.runner import run_agent_streaming
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@@ -64,6 +69,89 @@ web_chat_router = APIRouter(tags=["web-chat"])
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# Timeout for waiting for an agent response via Redis pub-sub (seconds)
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_RESPONSE_TIMEOUT_SECONDS = 180
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# ---------------------------------------------------------------------------
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# Connected user tracking — used to decide whether to send push notifications
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# ---------------------------------------------------------------------------
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# Maps user_id -> set of conversation_ids with active WebSocket connections.
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# When a user disconnects, their entry is removed. If the agent response
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# finishes after disconnect, a push notification is sent.
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_connected_users: dict[str, set[str]] = {}
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def _mark_connected(user_id: str, conversation_id: str) -> None:
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"""Record that user_id has an active WebSocket for conversation_id."""
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if user_id not in _connected_users:
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_connected_users[user_id] = set()
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_connected_users[user_id].add(conversation_id)
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def _mark_disconnected(user_id: str, conversation_id: str) -> None:
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"""Remove the active WebSocket record for user_id + conversation_id."""
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if user_id in _connected_users:
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_connected_users[user_id].discard(conversation_id)
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if not _connected_users[user_id]:
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del _connected_users[user_id]
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def is_user_connected(user_id: str) -> bool:
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"""Return True if the user has any active WebSocket connection."""
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return user_id in _connected_users and bool(_connected_users[user_id])
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async def _send_push_notification(
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user_id: str,
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title: str,
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body: str,
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conversation_id: str | None = None,
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) -> None:
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"""
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Fire-and-forget push notification delivery.
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Queries push_subscriptions for the user and calls pywebpush directly.
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Deletes stale (410 Gone) subscriptions automatically.
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Silently ignores errors — push is best-effort.
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"""
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from shared.models.push import PushSubscription
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from shared.api.push import _send_push
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try:
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user_uuid = uuid.UUID(user_id)
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payload = {
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"title": title,
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"body": body,
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"data": {"conversationId": conversation_id},
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}
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async with async_session_factory() as session:
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result = await session.execute(
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select(PushSubscription).where(PushSubscription.user_id == user_uuid)
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)
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subscriptions = result.scalars().all()
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if not subscriptions:
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return
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stale_endpoints: list[str] = []
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for sub in subscriptions:
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try:
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ok = await _send_push(sub, payload)
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if not ok:
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stale_endpoints.append(sub.endpoint)
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except Exception as exc:
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logger.warning("Push delivery failed for user=%s: %s", user_id, exc)
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if stale_endpoints:
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await session.execute(
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delete(PushSubscription).where(
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PushSubscription.user_id == user_uuid,
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PushSubscription.endpoint.in_(stale_endpoints),
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)
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)
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await session.commit()
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except Exception as exc:
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logger.warning("Push notification send error for user=%s: %s", user_id, exc)
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def normalize_web_event(event: dict[str, Any]) -> KonstructMessage:
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"""
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@@ -164,223 +252,248 @@ async def _handle_websocket_connection(
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user_id_str, user_role, tenant_id_str, conversation_id,
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)
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# Track this user as connected (for push notification gating)
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_mark_connected(user_id_str, conversation_id)
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# -------------------------------------------------------------------------
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# Step 2: Message loop
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# -------------------------------------------------------------------------
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while True:
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try:
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msg_data = await websocket.receive_json()
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except (WebSocketDisconnect, Exception):
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break
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try:
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while True:
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try:
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msg_data = await websocket.receive_json()
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except (WebSocketDisconnect, Exception):
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break
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if msg_data.get("type") != "message":
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continue
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if msg_data.get("type") != "message":
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continue
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text_content: str = msg_data.get("text", "") or ""
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agent_id_str: str = msg_data.get("agentId", "") or ""
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msg_conversation_id: str = msg_data.get("conversationId", conversation_id) or conversation_id
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display_name: str = msg_data.get("displayName", "Portal User")
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text_content: str = msg_data.get("text", "") or ""
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agent_id_str: str = msg_data.get("agentId", "") or ""
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msg_conversation_id: str = msg_data.get("conversationId", conversation_id) or conversation_id
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display_name: str = msg_data.get("displayName", "Portal User")
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# -------------------------------------------------------------------
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# a. Send typing indicator IMMEDIATELY — before any DB or Celery work
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# -------------------------------------------------------------------
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await websocket.send_json({"type": "typing"})
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# -------------------------------------------------------------------
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# a. Send typing indicator IMMEDIATELY — before any DB or Celery work
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# -------------------------------------------------------------------
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await websocket.send_json({"type": "typing"})
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# -------------------------------------------------------------------
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# b. Save user message to web_conversation_messages
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# -------------------------------------------------------------------
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configure_rls_hook(engine)
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rls_token = current_tenant_id.set(tenant_uuid)
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saved_conversation_id = msg_conversation_id
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# -------------------------------------------------------------------
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# b. Save user message to web_conversation_messages
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# -------------------------------------------------------------------
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configure_rls_hook(engine)
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rls_token = current_tenant_id.set(tenant_uuid)
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saved_conversation_id = msg_conversation_id
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try:
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async with async_session_factory() as session:
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# Look up the conversation to get tenant-scoped context
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conv_stmt = select(WebConversation).where(
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WebConversation.id == uuid.UUID(msg_conversation_id)
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try:
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async with async_session_factory() as session:
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# Look up the conversation to get tenant-scoped context
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conv_stmt = select(WebConversation).where(
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WebConversation.id == uuid.UUID(msg_conversation_id)
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)
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conv_result = await session.execute(conv_stmt)
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conversation = conv_result.scalar_one_or_none()
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if conversation is not None:
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# Save user message
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user_msg = WebConversationMessage(
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conversation_id=uuid.UUID(msg_conversation_id),
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tenant_id=tenant_uuid,
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role="user",
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content=text_content,
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)
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session.add(user_msg)
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# Update conversation timestamp
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await session.execute(
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text(
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"UPDATE web_conversations SET updated_at = NOW() WHERE id = :conv_id"
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),
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{"conv_id": str(msg_conversation_id)},
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)
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await session.commit()
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saved_conversation_id = msg_conversation_id
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except Exception:
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logger.exception(
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"Failed to save user message for conversation=%s", msg_conversation_id
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)
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conv_result = await session.execute(conv_stmt)
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conversation = conv_result.scalar_one_or_none()
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finally:
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current_tenant_id.reset(rls_token)
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if conversation is not None:
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# Save user message
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user_msg = WebConversationMessage(
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conversation_id=uuid.UUID(msg_conversation_id),
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tenant_id=tenant_uuid,
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role="user",
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content=text_content,
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)
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session.add(user_msg)
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# Update conversation timestamp
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await session.execute(
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text(
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"UPDATE web_conversations SET updated_at = NOW() WHERE id = :conv_id"
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),
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{"conv_id": str(msg_conversation_id)},
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)
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await session.commit()
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saved_conversation_id = msg_conversation_id
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except Exception:
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logger.exception(
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"Failed to save user message for conversation=%s", msg_conversation_id
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)
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finally:
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current_tenant_id.reset(rls_token)
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# -------------------------------------------------------------------
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# c. Build KonstructMessage and stream LLM response DIRECTLY
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#
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# Bypasses Celery entirely for web chat — calls the LLM pool's
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# streaming endpoint from the WebSocket handler. This eliminates
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# ~5-10s of Celery queue + Redis pub-sub round-trip overhead.
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# Slack/WhatsApp still use Celery (async webhook pattern).
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# -------------------------------------------------------------------
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event = {
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"text": text_content,
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"tenant_id": tenant_id_str,
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"agent_id": agent_id_str,
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"user_id": user_id_str,
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"display_name": display_name,
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"conversation_id": saved_conversation_id,
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}
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normalized_msg = normalize_web_event(event)
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# Load agent for this tenant
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agent: Agent | None = None
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rls_token3 = current_tenant_id.set(tenant_uuid)
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try:
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async with async_session_factory() as session:
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from sqlalchemy import select as sa_select
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agent_stmt = sa_select(Agent).where(
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Agent.tenant_id == tenant_uuid,
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Agent.is_active == True,
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).limit(1)
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agent_result = await session.execute(agent_stmt)
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agent = agent_result.scalar_one_or_none()
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finally:
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current_tenant_id.reset(rls_token3)
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if agent is None:
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await websocket.send_json({
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"type": "done",
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"text": "No active AI employee is configured for this workspace.",
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"conversation_id": saved_conversation_id,
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})
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continue
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# Build memory-enriched messages (Redis sliding window only — fast)
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redis_mem = aioredis.from_url(settings.redis_url)
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try:
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recent_messages = await get_recent_messages(
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redis_mem, tenant_id_str, str(agent.id), user_id_str
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)
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finally:
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await redis_mem.aclose()
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enriched_messages = build_messages_with_memory(
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agent=agent,
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current_message=text_content,
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recent_messages=recent_messages,
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relevant_context=[],
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channel="web",
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)
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# Stream LLM response directly to WebSocket — no Celery, no pub-sub
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response_text = ""
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try:
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async for token in run_agent_streaming(
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msg=normalized_msg,
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agent=agent,
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messages=enriched_messages,
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):
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response_text += token
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try:
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await websocket.send_json({"type": "chunk", "text": token})
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except Exception:
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break # Client disconnected
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except Exception:
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logger.exception("Direct streaming failed for conversation=%s", saved_conversation_id)
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if not response_text:
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response_text = "I encountered an error processing your message. Please try again."
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# Save to Redis sliding window (fire-and-forget, non-blocking)
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redis_mem2 = aioredis.from_url(settings.redis_url)
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try:
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await append_message(redis_mem2, tenant_id_str, str(agent.id), user_id_str, "user", text_content)
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if response_text:
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await append_message(redis_mem2, tenant_id_str, str(agent.id), user_id_str, "assistant", response_text)
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finally:
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await redis_mem2.aclose()
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# Fire-and-forget embedding for long-term memory
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try:
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embed_and_store.delay({
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# -------------------------------------------------------------------
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# c. Build KonstructMessage and stream LLM response DIRECTLY
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#
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# Bypasses Celery entirely for web chat — calls the LLM pool's
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# streaming endpoint from the WebSocket handler. This eliminates
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# ~5-10s of Celery queue + Redis pub-sub round-trip overhead.
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# Slack/WhatsApp still use Celery (async webhook pattern).
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# -------------------------------------------------------------------
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event = {
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"text": text_content,
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"tenant_id": tenant_id_str,
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"agent_id": str(agent.id),
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"agent_id": agent_id_str,
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"user_id": user_id_str,
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"role": "user",
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"content": text_content,
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})
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if response_text:
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"display_name": display_name,
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"conversation_id": saved_conversation_id,
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}
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normalized_msg = normalize_web_event(event)
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# Load agent for this tenant
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agent: Agent | None = None
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rls_token3 = current_tenant_id.set(tenant_uuid)
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try:
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async with async_session_factory() as session:
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from sqlalchemy import select as sa_select
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agent_stmt = sa_select(Agent).where(
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Agent.tenant_id == tenant_uuid,
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Agent.is_active == True,
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).limit(1)
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agent_result = await session.execute(agent_stmt)
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agent = agent_result.scalar_one_or_none()
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finally:
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current_tenant_id.reset(rls_token3)
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if agent is None:
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await websocket.send_json({
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"type": "done",
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"text": "No active AI employee is configured for this workspace.",
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"conversation_id": saved_conversation_id,
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})
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continue
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# Build memory-enriched messages (Redis sliding window only — fast)
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redis_mem = aioredis.from_url(settings.redis_url)
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try:
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recent_messages = await get_recent_messages(
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redis_mem, tenant_id_str, str(agent.id), user_id_str
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)
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finally:
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await redis_mem.aclose()
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enriched_messages = build_messages_with_memory(
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agent=agent,
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current_message=text_content,
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recent_messages=recent_messages,
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relevant_context=[],
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channel="web",
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)
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# Stream LLM response directly to WebSocket — no Celery, no pub-sub
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response_text = ""
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ws_disconnected_during_stream = False
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try:
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async for token in run_agent_streaming(
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msg=normalized_msg,
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agent=agent,
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messages=enriched_messages,
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):
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response_text += token
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try:
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await websocket.send_json({"type": "chunk", "text": token})
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except Exception:
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ws_disconnected_during_stream = True
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break # Client disconnected
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except Exception:
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logger.exception("Direct streaming failed for conversation=%s", saved_conversation_id)
|
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if not response_text:
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response_text = "I encountered an error processing your message. Please try again."
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|
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# Save to Redis sliding window (fire-and-forget, non-blocking)
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redis_mem2 = aioredis.from_url(settings.redis_url)
|
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try:
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await append_message(redis_mem2, tenant_id_str, str(agent.id), user_id_str, "user", text_content)
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if response_text:
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await append_message(redis_mem2, tenant_id_str, str(agent.id), user_id_str, "assistant", response_text)
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finally:
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await redis_mem2.aclose()
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# Fire-and-forget embedding for long-term memory
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try:
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embed_and_store.delay({
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"tenant_id": tenant_id_str,
|
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"agent_id": str(agent.id),
|
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"user_id": user_id_str,
|
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"role": "assistant",
|
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"content": response_text,
|
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"role": "user",
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"content": text_content,
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||||
})
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except Exception:
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pass # Non-fatal — memory will rebuild over time
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|
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# -------------------------------------------------------------------
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# e. Save assistant message and send final "done" to client
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# -------------------------------------------------------------------
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||||
if response_text:
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rls_token2 = current_tenant_id.set(tenant_uuid)
|
||||
try:
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async with async_session_factory() as session:
|
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assistant_msg = WebConversationMessage(
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conversation_id=uuid.UUID(saved_conversation_id),
|
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tenant_id=tenant_uuid,
|
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role="assistant",
|
||||
content=response_text,
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)
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session.add(assistant_msg)
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await session.execute(
|
||||
text(
|
||||
"UPDATE web_conversations SET updated_at = NOW() WHERE id = :conv_id"
|
||||
),
|
||||
{"conv_id": str(saved_conversation_id)},
|
||||
)
|
||||
await session.commit()
|
||||
if response_text:
|
||||
embed_and_store.delay({
|
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"tenant_id": tenant_id_str,
|
||||
"agent_id": str(agent.id),
|
||||
"user_id": user_id_str,
|
||||
"role": "assistant",
|
||||
"content": response_text,
|
||||
})
|
||||
except Exception:
|
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logger.exception(
|
||||
"Failed to save assistant message for conversation=%s", saved_conversation_id
|
||||
pass # Non-fatal — memory will rebuild over time
|
||||
|
||||
# -------------------------------------------------------------------
|
||||
# e. Save assistant message and send final "done" to client
|
||||
# -------------------------------------------------------------------
|
||||
if response_text:
|
||||
rls_token2 = current_tenant_id.set(tenant_uuid)
|
||||
try:
|
||||
async with async_session_factory() as session:
|
||||
assistant_msg = WebConversationMessage(
|
||||
conversation_id=uuid.UUID(saved_conversation_id),
|
||||
tenant_id=tenant_uuid,
|
||||
role="assistant",
|
||||
content=response_text,
|
||||
)
|
||||
session.add(assistant_msg)
|
||||
await session.execute(
|
||||
text(
|
||||
"UPDATE web_conversations SET updated_at = NOW() WHERE id = :conv_id"
|
||||
),
|
||||
{"conv_id": str(saved_conversation_id)},
|
||||
)
|
||||
await session.commit()
|
||||
except Exception:
|
||||
logger.exception(
|
||||
"Failed to save assistant message for conversation=%s", saved_conversation_id
|
||||
)
|
||||
finally:
|
||||
current_tenant_id.reset(rls_token2)
|
||||
|
||||
# If user disconnected during streaming, send push notification
|
||||
if ws_disconnected_during_stream or not is_user_connected(user_id_str):
|
||||
agent_name = agent.name if hasattr(agent, "name") and agent.name else "Your AI Employee"
|
||||
preview = response_text[:100] + ("..." if len(response_text) > 100 else "")
|
||||
asyncio.create_task(
|
||||
_send_push_notification(
|
||||
user_id=user_id_str,
|
||||
title=f"{agent_name} replied",
|
||||
body=preview,
|
||||
conversation_id=saved_conversation_id,
|
||||
)
|
||||
)
|
||||
if ws_disconnected_during_stream:
|
||||
break # Stop the message loop — WS is gone
|
||||
|
||||
# Signal stream completion to the client
|
||||
try:
|
||||
await websocket.send_json({
|
||||
"type": "done",
|
||||
"text": response_text,
|
||||
"conversation_id": saved_conversation_id,
|
||||
})
|
||||
except Exception:
|
||||
pass # Client already disconnected
|
||||
else:
|
||||
logger.warning(
|
||||
"No response received for conversation=%s", saved_conversation_id,
|
||||
)
|
||||
finally:
|
||||
current_tenant_id.reset(rls_token2)
|
||||
try:
|
||||
await websocket.send_json({
|
||||
"type": "error",
|
||||
"message": "I'm having trouble responding right now. Please try again.",
|
||||
})
|
||||
except Exception:
|
||||
pass # Client already disconnected
|
||||
|
||||
# Signal stream completion to the client
|
||||
try:
|
||||
await websocket.send_json({
|
||||
"type": "done",
|
||||
"text": response_text,
|
||||
"conversation_id": saved_conversation_id,
|
||||
})
|
||||
except Exception:
|
||||
pass # Client already disconnected
|
||||
else:
|
||||
logger.warning(
|
||||
"No response received for conversation=%s", saved_conversation_id,
|
||||
)
|
||||
try:
|
||||
await websocket.send_json({
|
||||
"type": "error",
|
||||
"message": "I'm having trouble responding right now. Please try again.",
|
||||
})
|
||||
except Exception:
|
||||
pass # Client already disconnected
|
||||
finally:
|
||||
# Always untrack this user when connection ends
|
||||
_mark_disconnected(user_id_str, conversation_id)
|
||||
|
||||
|
||||
@web_chat_router.websocket("/chat/ws/{conversation_id}")
|
||||
|
||||
@@ -48,6 +48,7 @@ from shared.api import (
|
||||
invitations_router,
|
||||
llm_keys_router,
|
||||
portal_router,
|
||||
push_router,
|
||||
templates_router,
|
||||
usage_router,
|
||||
webhook_router,
|
||||
@@ -158,6 +159,11 @@ app.include_router(templates_router)
|
||||
app.include_router(chat_router) # REST: /api/portal/chat/*
|
||||
app.include_router(web_chat_router) # WebSocket: /chat/ws/{conversation_id}
|
||||
|
||||
# ---------------------------------------------------------------------------
|
||||
# Phase 8 Push Notification router
|
||||
# ---------------------------------------------------------------------------
|
||||
app.include_router(push_router) # Push subscribe/unsubscribe/send
|
||||
|
||||
|
||||
# ---------------------------------------------------------------------------
|
||||
# Routes
|
||||
|
||||
@@ -18,6 +18,7 @@ dependencies = [
|
||||
"httpx>=0.28.0",
|
||||
"redis>=5.0.0",
|
||||
"boto3>=1.35.0",
|
||||
"pywebpush>=2.0.0",
|
||||
]
|
||||
|
||||
[tool.uv.sources]
|
||||
|
||||
Reference in New Issue
Block a user