Real-Time Delivery

EdgeStream Topic Architecture

Each user has a dedicated EdgeStream topic for notifications: notifications.{userId}. When WorkDesk's NotificationService creates a notification for a user, it publishes the event payload to this topic. The user's connected browser session receives it immediately.

// Topic naming pattern
notifications.usr-001     // user usr-001's notification topic
notifications.usr-002     // user usr-002's notification topic
// ... fully isolated per user

Subscription Lifecycle

React Subscription Code

import { useSubscription } from '@bizfirstai/edge-stream-react';
import { useNotificationStore } from '../stores/notificationStore';

// WorkDeskShell — subscribes once on mount
export function WorkDeskShell({ children }: { children: React.ReactNode }) {
  const userId = useCurrentUser().id;
  const { addNotification, incrementUnread } = useNotificationStore();

  // Subscribe to user's notification topic
  useSubscription(`notifications.${userId}`, (event: EdgeStreamEvent) => {
    const notification: Notification = {
      id: event.payload.notificationId,
      type: event.payload.type,
      title: event.payload.title,
      body: event.payload.body,
      priority: event.payload.priority,
      linkedUrl: event.payload.linkedUrl,
      createdAt: event.payload.createdAt,
      isRead: false,
    };
    addNotification(notification);
    incrementUnread();

    // Show browser toast for high-priority notifications
    if (event.payload.priority === 'urgent' || event.payload.priority === 'high') {
      showToast(notification);
    }
  });

  return <div className="workdesk-shell">{children}</div>;
}

EdgeStream Event Payload

// Full notification event payload from EdgeStream
interface NotificationEvent {
  notificationId: string;        // unique notification ID
  type: 'hil_task_assigned'
      | 'workflow_completed'
      | 'hil_task_overdue'
      | 'system_alert';
  title: string;                 // short notification title
  body: string;                  // full notification body text
  priority: 'low' | 'normal' | 'high' | 'urgent';
  linkedUrl: string;             // deep-link to the relevant resource
  createdAt: string;             // ISO 8601 UTC
  metadata: {
    taskId?: string;
    executionId?: string;
    workflowName?: string;
    workflowId?: string;
  };
}

Reconnection and Missed Events

If the browser session is closed and reopened (e.g., employee shuts laptop and returns the next day), EdgeStream's reconnection window may not replay missed events. WorkDesk handles this by loading recent unread notifications from the REST API on every session start, ensuring no notifications are missed even after a disconnection.

// On session start — load recent unread notifications from API
// (in case EdgeStream missed events while offline)
GET /api/workdesk/notifications?isRead=false&limit=50&sortBy=createdAt&sortDir=desc