Hi Medplum Team! From what we're seeing it looks like cursor based pagination (described in FHIR standard here: https://hl7.org/fhir/graphql.html#searching) is not yet supported, or at least for all our queries the property

next

is always null, even when there are more items. Is this assessment accurate, and if so, is supporting cursor based pagination planned? i'm happy to create a ticket in github if that's the correct next step.

Hi @Elliot ! Cursor-based pagination is enabled by default if you

_sort=-_lastUpdated

, and you should be able to reach past the 10k resources mark. Our customers have been able to do with graphql when using this parameter (and nothing else added to _sort), it uses the same codepath as our normal search https://www.medplum.com/docs/search/paginated-search

Thanks @Maddy for taking a look. For non-graphQL search the

next

parameter (which contains the cursor) is packaged into the

Bundle

container and that's easy to find. The graphQL interface doesn't return this bundle structure but it does provider a

next

parameter on

*Connection

queries, for example:

query {
  TaskConnection(_sort: "_lastUpdated") {
    next
    last
    first
    previous
    pageSize
    edges {
      resource {
        id
      }
    }
  }
}

running the above with

medplum.graphql

gives a response that looks like this:

{
  "data": {
    "TaskConnection": {
      "next": null,
      "last": null,
      "first": null,
      "previous": null,
      "pageSize": 20,
      "edges": [...]

I checked the full http request to double check

next

wasn't returned in the headers or something. Can you tell the me the right way to access a cursor when using the graphQL interface? I checked all available docs and the original PR that implemented cursor search but it wasn't clear to me where the search links are exposed through GraphQL

Hi @Elliot , is there a chance that adding

link

to your query parameters might expose the next parameter?

link

isn't a parameter to the

TaskConnection

or

TaskList

query type, or a field of the`TaskConnection` or

TaskList

return types, so adding it anywhere on the query i shared above is just a type error:

"details": {
              "text": "Cannot query field \"link\" on type \"TaskConnection\"."
            }

There is of course a

link

on the

Bundle

type and I assume this is what you're referencing (and also where we would find

_cursor

on a non-graphql query), but graphQL queries don't wrap the results in a Bundle by default and I don't see any way to construct a query where results for some arbitrary query are wrapped in a

Bundle

. if you have a basic working example of course please let me know.

Hi @Elliot - thanks for filing this. You are correct, it looks like the "next" link is absent from our implementation of the GraphQL Connection API. I filed a tracking ticket here with details on how to fix. The good news is that the

Bundle

has the values, it's just not being returned in the Connection API at the moment. https://github.com/medplum/medplum/issues/7428