API Pagination Cursor

[gustavofiretti]

Hello,

I'm trying to retrave data use an API, and i tested it in PostMan and it gaves me a json file.

The API has a limit of 25 lines per page, and in the json i can see the link to the next page:

I can connect the API in power query and see these 25 lines, but how can I gather all pages to one sigle table?

Here is the "Advanced editor" code

let
    Source = Json.Document(Web.Contents("https://api.deskbee.io/v1.1/bookings?state=last",
    [Headers=[Authorization="TOKEN"]])),
    #"Converted to Table" = Table.FromRecords({Source}),
    #"Expanded data" = Table.ExpandListColumn(#"Converted to Table", "data"),
    #"Expanded data1" = Table.ExpandRecordColumn(#"Expanded data", "data", {"uuid", "start_date", "end_date", "place", "state", "person", "owner", "created_at", "updated_at", "deleted_at"}, {"data.uuid", "data.start_date", "data.end_date", "data.place", "data.state", "data.person", "data.owner", "data.created_at", "data.updated_at", "data.deleted_at"}),
    #"Expanded data.place" = Table.ExpandRecordColumn(#"Expanded data1", "data.place", {"uuid", "qrcode", "type", "name", "name_display", "capacity", "area", "sector", "external_resource_id", "is_mapped", "created_at", "updated_at"}, {"data.place.uuid", "data.place.qrcode", "data.place.type", "data.place.name", "data.place.name_display", "data.place.capacity", "data.place.area", "data.place.sector", "data.place.external_resource_id", "data.place.is_mapped", "data.place.created_at", "data.place.updated_at"}),
    #"Expanded data.place.area" = Table.ExpandRecordColumn(#"Expanded data.place", "data.place.area", {"address", "floor", "building", "site"}, {"data.place.area.address", "data.place.area.floor", "data.place.area.building", "data.place.area.site"}),
    #"Expanded data.place.area.floor" = Table.ExpandRecordColumn(#"Expanded data.place.area", "data.place.area.floor", {"uuid", "name", "is_active"}, {"data.place.area.floor.uuid", "data.place.area.floor.name", "data.place.area.floor.is_active"}),
    #"Expanded data.place.area.building" = Table.ExpandRecordColumn(#"Expanded data.place.area.floor", "data.place.area.building", {"uuid", "name", "address", "is_active"}, {"data.place.area.building.uuid", "data.place.area.building.name", "data.place.area.building.address", "data.place.area.building.is_active"}),
    #"Expanded data.place.area.site" = Table.ExpandRecordColumn(#"Expanded data.place.area.building", "data.place.area.site", {"uuid", "name", "is_active"}, {"data.place.area.site.uuid", "data.place.area.site.name", "data.place.area.site.is_active"}),
    #"Expanded data.person" = Table.ExpandRecordColumn(#"Expanded data.place.area.site", "data.person", {"uuid", "name", "name_display", "email", "enrollment", "created_at", "updated_at"}, {"data.person.uuid", "data.person.name", "data.person.name_display", "data.person.email", "data.person.enrollment", "data.person.created_at", "data.person.updated_at"}),
    #"Expanded data.owner" = Table.ExpandRecordColumn(#"Expanded data.person", "data.owner", {"uuid", "name", "name_display", "email", "enrollment", "created_at", "updated_at"}, {"data.owner.uuid", "data.owner.name", "data.owner.name_display", "data.owner.email", "data.owner.enrollment", "data.owner.created_at", "data.owner.updated_at"}),
    #"Expanded links" = Table.ExpandRecordColumn(#"Expanded data.owner", "links", {"first", "last", "prev", "next"}, {"links.first", "links.last", "links.prev", "links.next"}),
    #"Expanded meta" = Table.ExpandRecordColumn(#"Expanded links", "meta", {"path", "per_page"}, {"meta.path", "meta.per_page"}),
    #"Changed Type" = Table.TransformColumnTypes(#"Expanded meta",{{"data.uuid", type text}, {"data.start_date", type datetimezone}, {"data.end_date", type datetimezone}, {"data.place.uuid", type text}, {"data.place.qrcode", type text}, {"data.place.type", type text}, {"data.place.name", type text}, {"data.place.name_display", type text}, {"data.place.capacity", Int64.Type}, {"data.place.area.address", type text}, {"data.place.area.floor.uuid", type text}, {"data.place.area.floor.name", type text}, {"data.place.area.floor.is_active", type logical}, {"data.place.area.building.uuid", type text}, {"data.place.area.building.name", type text}, {"data.place.area.building.address", type text}, {"data.place.area.building.is_active", type logical}, {"data.place.area.site.uuid", type text}, {"data.place.area.site.name", type text}, {"data.place.area.site.is_active", type logical}, {"data.place.sector", type any}, {"data.place.external_resource_id", type any}, {"data.place.is_mapped", type logical}, {"data.place.created_at", type datetimezone}, {"data.place.updated_at", type datetimezone}, {"data.state", type text}, {"data.person.uuid", type text}, {"data.person.name", type text}, {"data.person.name_display", type text}, {"data.person.email", type text}, {"data.person.enrollment", type any}, {"data.person.created_at", type datetimezone}, {"data.person.updated_at", type datetimezone}, {"data.owner.uuid", type text}, {"data.owner.name", type text}, {"data.owner.name_display", type text}, {"data.owner.email", type text}, {"data.owner.enrollment", type any}, {"data.owner.created_at", type datetimezone}, {"data.owner.updated_at", type datetimezone}, {"data.created_at", type datetimezone}, {"data.updated_at", type datetimezone}, {"data.deleted_at", type any}, {"links.first", type any}, {"links.last", type any}, {"links.prev", type any}, {"links.next", type text}, {"meta.path", type text}, {"meta.per_page", Int64.Type}})
in
    #"Changed Type"

Can you help me, please?

Thank you.

[amitchandak]

@gustavofiretti , Check if API pagination can help

https://medium.com/@marktiedemann/how-to-do-pagination-in-power-query-430460c17c78

https://datachant.com/2016/06/27/cursor-based-pagination-power-query/

[gustavofiretti]

Thank you @amitchandak , but i've tried those topics and  i wasn't able to adapt it to my code.

[otravers]

To solve an unfamiliar problem, try breaking it down into the smallest possible challenge. Right now you don't know how to handle pagination, so focus on solving that by getting everything else out of the way.

Create a copy of your query, remove everything but the source, turn that query into a function, and try adding pagination as explained in the links Amit gave you. Once you have pagination working, you can add back all the post-API processing from your initial query.

[gustavofiretti]

Hello @otravers .

I tried to do this, i deleted all of the unecessary code and now i got this:

let

    Token = "XXX",
    iterations = 2,
    url = "https://api.deskbee.io/v1.1/bookings?",
    Source = Json.Document(Web.Contents(url,
    [Headers=[Authorization=Token]])),

    FnGetOnePage =
  (url) as record =>
   let
    data = try Source[data] otherwise null,
    next = try Source[links][next] otherwise null,
    res = [Data=data, Next=next]
   in
    res,
 
 GeneratedList =
  List.Generate(
   ()=>[i=0, res = FnGetOnePage(url)],
   each [i]<iterations and [res][Data]<>null,
   each [i=[i]+1, res = FnGetOnePage([res][Next])],
   each [res][Data])
in
    GeneratedList

But now i got the same data from page 1 twice (number os iterations) i'm not getting the new page's data yet.

I'm not a dev, so I'm basicly trying to replace the code and adapting it to my case. 

[otravers]

You're making progress. "Being a dev" starts with thinking logically. How does your API handle paging? Is it a URL parameter? Or something in the header? You have to make the API aware of the page you want to retrieve each time you call it.

[gustavofiretti]

The API gives me another URL to the next page, like that: 

But for some reason, the code is not replacing this new URL. 

about the logic, i think i'm in the righ way, but i don't know much about M language.

I understand that the code need to generate a list, then replace de last url for the next url and generate a new list and then combinate those lists. 

The other thing is i think that i don't need the iteration number, because i need to do this loop until the link "next" be null.

[BRVL]

see my post: Solved: Re: Web based cursor pagination issue - Microsoft Power BI Community

should help since it's cursor based pagination.