Events (SSE)

Subscribe to Server-Sent Events for real-time order updates. This enables live dashboards, kitchen displays, and cashier systems to receive instant notifications.

How SSE Works

Client opens a long-lived HTTP connection
Server pushes updates as they occur
Connection stays open with periodic keep-alive messages (every 15 seconds)
Client automatically reconnects if the connection is lost

GET `/events/{channel}`

Establish a persistent SSE connection for a specific channel.

Authentication: Bearer token (admin or operator)

Path Parameters

Parameter	Type	Description
`channel`	`string`	Event channel: `cashier`, `display`, or `printer`

Response Headers


Content-Type: text/event-stream
Cache-Control: no-cache
Connection: keep-alive

Message Format

Keep-alive (every 15 seconds):


: keep-alive

Data event:


data: {"displayCode":"A01","ticketNumber":1,"id":1}

Available Channels

`cashier`

Broadcasts real-time updates for the cashier interface when orders are created or confirmed.

Event: new-order — Fired when a new order is placed.


{
  "id": 1,
  "displayCode": "A01",
  "table": "3",
  "customer": "John Doe",
  "createdAt": "2026-01-15T18:30:00.000Z",
  "confirmedAt": null,
  "ticketNumber": null,
  "status": "PENDING",
  "paymentMethod": null,
  "subTotal": "25",
  "discount": "0",
  "surcharge": "0",
  "total": "25",
  "userId": null,
  "cashRegisterId": null,
  "orderItems": [
    {
      "id": "clx0abc0001mx01example",
      "quantity": 2,
      "orderId": 1,
      "foodId": "clx0def0002mx01example",
      "unitPrice": "12.5",
      "unitSurcharge": "0",
      "total": "25",
      "notes": "No onions"
    }
  ]
}

Event: confirmed-order — Fired when an order is confirmed by a cashier.


{
  "displayCode": "A01",
  "ticketNumber": 1,
  "id": 1
}

`display`

Broadcasts real-time updates for display systems (kitchen screens, customer-facing displays) when order confirmations occur.

Event: confirmed-order — Fired when an order is confirmed.


{
  "displayCode": "A01",
  "ticketNumber": 1,
  "id": 1
}

`printer`

Broadcasts real-time updates for printers when a cashier confirms a new order.

Event: confirmed-order — Fired when an order is confirmed, includes full order details for printing.


{
  "id": 1,
  "displayCode": "A01",
  "table": "3",
  "customer": "John Doe",
  "createdAt": "2026-01-15T18:30:00.000Z",
  "confirmedAt": "2026-01-15T18:35:12.000Z",
  "ticketNumber": 1,
  "status": "CONFIRMED",
  "paymentMethod": "CASH",
  "subTotal": "25",
  "discount": "2",
  "surcharge": "1",
  "total": "24",
  "userId": "clx0usr0003mx01example",
  "cashRegisterId": "clx0csh0004mx01example",
  "orderItems": [
    {
      "id": "clx0abc0001mx01example",
      "quantity": 2,
      "orderId": 1,
      "notes": "Extra spicy",
      "unitPrice": "12.5",
      "unitSurcharge": "0.5",
      "total": "26",
      "food": {
        "id": "clx0def0002mx01example",
        "name": "Margherita",
        "printerId": null
      }
    }
  ]
}

Event: reprint-order — Fired when a cashier requests a reprint of specific order items or the receipt. Contains reprintOrderItems (only the selected items) and reprintReceipt (whether to reprint the receipt), alongside the full orderItems list.


{
  "id": 1,
  "displayCode": "A01",
  "table": "3",
  "customer": "John Doe",
  "createdAt": "2026-01-15T18:30:00.000Z",
  "confirmedAt": "2026-01-15T18:35:12.000Z",
  "ticketNumber": 1,
  "status": "CONFIRMED",
  "paymentMethod": "CASH",
  "subTotal": "25",
  "discount": "2",
  "surcharge": "1",
  "total": "24",
  "userId": "clx0usr0003mx01example",
  "cashRegisterId": "clx0csh0004mx01example",
  "reprintReceipt": true,
  "reprintOrderItems": [
    {
      "id": "clx0abc0001mx01example",
      "orderId": 1,
      "foodId": "clx0def0002mx01example",
      "quantity": 2,
      "notes": "Extra spicy",
      "unitPrice": "12.5",
      "unitSurcharge": "0.5",
      "total": "26",
      "food": {
        "id": "clx0def0002mx01example",
        "name": "Margherita",
        "printerId": null
      }
    }
  ],
  "orderItems": [
    {
      "id": "clx0abc0001mx01example",
      "orderId": 1,
      "foodId": "clx0def0002mx01example",
      "quantity": 2,
      "notes": "Extra spicy",
      "unitPrice": "12.5",
      "unitSurcharge": "0.5",
      "total": "26",
      "food": {
        "id": "clx0def0002mx01example",
        "name": "Margherita",
        "printerId": null
      }
    }
  ]
}

Client Example


const eventSource = new EventSource('/events/cashier', {
  headers: { 'Authorization': 'Bearer YOUR_TOKEN' }
});
 
eventSource.onmessage = (event) => {
  const orderData = JSON.parse(event.data);
  console.log('Order update:', orderData);
};
 
eventSource.onerror = (error) => {
  console.error('SSE connection error:', error);
};

Errors

Status	Description
`400`	Invalid channel parameter
`401`	Unauthorized — authentication required
`403`	Forbidden — insufficient permissions