Check if JSON Attribute Exists

Thanks Stachu , that was what I was looking for!

Updated function:

GetPage = (Index as number, Scope as text, Offset as number) =>
    let
        // Calculate the offset. 
        _offset = Number.ToText(Index * LimitPerPage + Offset),
        // Try to fetch a JSON payload. If an error occurs, return a JSON document with an empty "data" attribute.
        JSON = try GetJSON(api_source_uri & Scope & "?page[limit]=" & strLimitPerPage & "&page[offset]=" & _offset) otherwise Json.Document("{""data"": []}"),
        // Get the ""data"" attribute of the JSON document.
        Page = JSON[data]
    in
        Page;