Relative Cursor: ForwardCursors field does not contain last page

[nickodei]

Product

Green Donut

Version

15.1.3

Link to minimal reproduction

not needed

Steps to reproduce

Using a query with a relative cursor, where you fetch with first an amount of items that is not divisible by the totalCount to an integer.

What is expected?

You get a cursor to the last page (here its page 2 because 12 / 10 > 1) when fetching the first 10 elements:

query(first: 10) { ... }

{
  "data": {
    "query": {
      "pageInfo": {
        "hasNextPage": true,
        "hasPreviousPage": false,
        "backwardCursors": [],
        "forwardCursors": [
          {
            "page": 2,
            "cursor": "base64 encoded id"
          }
        ]
      },
      "totalCount": 12
    }
  }
}

What is actually happening?

You get an empty list for the forwardCursors:

{
  "data": {
    "query": {
      "pageInfo": {
        "hasNextPage": true,
        "hasPreviousPage": false,
        "backwardCursors": [],
        "forwardCursors": []
      },
      "totalCount": 12
    }
  }
}

Relevant log output

Additional context

This happens because we divide the TotalCount by the RequestedSize and we get an integer. We need to round up when there is a residual to get a cursor to the last items. Using Math.Ceiling or something like that.

graphql-platform/src/GreenDonut/src/GreenDonut.Data/Extensions/GreenDonutPageExtensions.cs

Line 115 in 819f23c

var totalPages = (page.TotalCount ?? 0) / (page.RequestedSize ?? 10);