Digital ordering

This use case is aimed at Digital Ordering Systems and it describes how to use the Mews POS API to manage digital orders, including:

• Browsing the product catalog

• Creating and managing orders

• Processing payments

Contents

• Products endpoint polling to get availability updates

• Orders endpoint polling to get most recent order state changes

Products endpoint polling to get availability updates

Digital ordering systems need to stay synchronized with real-time product availability changes. Use the Get products endpoint with filtering and sparse fieldsets to efficiently poll for availability updates.

Polling strategy

Poll the products endpoint using the updatedAtGteq or updatedAtGt filters to retrieve only products that have been updated since your last check. Use sparse fieldsets to minimize bandwidth by requesting only the isAvailable field.

Example request:

GET https://api.pos.mews-demo.com/v1/products?filter[updatedAtGteq]=2025-03-12&fields[products]=isAvailable

Example response:

{
  "data": [
    {
      "id": "139a7f7a-591f-4797-ba23-08c9bee0d044",
      "type": "products",
      "attributes": {
        "isAvailable": false
      }
    },
    {
      "id": "2a8b9c1d-4e5f-6789-abcd-ef1234567890",
      "type": "products",
      "attributes": {
        "isAvailable": true
      }
    }
  ]
}

Orders endpoint polling to get most recent order state changes

Track order state changes in real-time by polling the Get orders endpoint with filtering and sparse fieldsets to monitor order lifecycle updates.

Polling strategy

Poll the orders endpoint using the updatedAtGteq or updatedAtGt filters to retrieve only orders that have been updated since your last check. Use sparse fieldsets to request only the state field for efficient bandwidth usage.

Example request:

GET https://api.pos.mews-demo.com/v1/orders?filter[updatedAtGteq]=2025-05-16&fields[orders]=state

Example response:

{
  "data": [
    {
      "id": "5624013b-5293-48b1-a07a-e7ee01cbde6a",
      "type": "orders",
      "attributes": {
        "state": "closed"
      }
    },
    {
      "id": "7c8d9e0f-1234-5678-9abc-def012345678",
      "type": "orders",
      "attributes": {
        "state": "open"
      }
    }
  ]
}

Fetch covers for a table at a specific table

Polling strategy

To retrieve the actual covers (guests seated) for a table, you have to poll the Get orders and include the filter[tableIdEq] query parameter.

Example request:

GET https://api.pos.mews-demo.com/v1/orders?filter[tableIdEq]=6d5e100c-5bf9-4781-85ec-cdf183e9486f

Example response:

{
  "data": [
    {
      "id": "e194c497-f601-49c7-b952-08f329a5779e",
      "type": "orders",
      "attributes": {
        "notes": null,
        "createdAt": "2025-09-25T11:23:18.367Z",
        "updatedAt": "2025-09-25T11:24:24.344Z",
        "depositAmount": null,
        "tableStatus": "seated",
        "state": "paid",
        "covers": 4
      },
      "relationships": {
        "tables": {
          "data": [
            {
              "id": "6d5e100c-5bf9-4781-85ec-cdf183e9486f",
              "type": "tables"
            }
          ]
        }
      }
    }
  ]
}

Room charge

Room Number Validation for Payments

When creating a payment, the room_charge payment method is the only scenario in which a roomNumber value is permitted. This is because room-charge payments must be associated with a specific guest room for proper billing.

If the payment method is anything other than room_charge, the roomNumber field must be omitted. Including a room number for non–room-charge payments causes the request to fail validation.

Errors

Room number must be blank

roomNumber is only allowed when the payment method is room-service (e.g., room_charge). If roomNumber is provided with any other payment method, the request fails with HTTP 422 (Unprocessable Content).

{
  "errors": [
    {
      "status": "422",
      "source": {
        "pointer": "/data/attributes/roomNumber"
      },
      "title": "Unprocessable Content",
      "detail": "Room number must be blank",
      "code": "present"
    }
  ]
}

In short: If the payment isn’t a room-charge payment, don’t send a room number.