Power Query Pagination Example

power-query-pagination.m

let 
    BaseUrl         = "https://fake-odata-api.com/v1/Entities?",
    Token           = "F4K3-T0K3N-D0NT-U5E-L0L",
    EntitiesPerPage = 1000,
 
    GetJson = (Url) =>
        let Options = [Headers=[ #"Authorization" = "Bearer " & Token ]],
            RawData = Web.Contents(Url, Options),
            Json    = Json.Document(RawData)
        in  Json,
 
    GetEntityCount = () =>
        let Url   = BaseUrl & "$count=true&$top=0",
            Json  = GetJson(Url),
            Count = Json[#"@odata.count"]
        in  Count,
 
    GetPage = (Index) =>
        let Skip  = "$skip=" & Text.From(Index * EntitiesPerPage),
            Top   = "$top=" & Text.From(EntitiesPerPage),
            Url   = BaseUrl & Skip & "&" & Top,
            Json  = GetJson(Url),
            Value = Json[#"value"]
        in  Value,
 
    EntityCount = List.Max({ EntitiesPerPage, GetEntityCount() }),
    PageCount   = Number.RoundUp(EntityCount / EntitiesPerPage),
    PageIndices = { 0 .. PageCount - 1 },
    Pages       = List.Transform(PageIndices, each GetPage(_)),
    Entities    = List.Union(Pages),
    Table       = Table.FromList(Entities, Splitter.SplitByNothing(), null, null, ExtraValues.Error)
in
    Table