FHIR

better-supabase/fhir turns the rows of the care blocks into HL7 FHIR R4 resources, and reads FHIR Observation and MedicationRequest resources back into the shape the blocks import. It has pure functions only: no tables, no SQL module and no FHIR type package. Its types are structural, so a resource from any FHIR library fits, and it runs on every WinterTC runtime. The FHIR version it follows, 4.0.1, is pinned in SPEC_PINS.fhirR4.

import {
  fromFhirObservation,
  toFhirBundle,
  toFhirCarePlan,
  toFhirObservation,
} from "better-supabase/fhir";

The mappers produce base R4 resources. National profiles such as the Dutch zib, eOverdracht and MedMij profiles are out of scope; a profile layer can extend the output with the meta.profile, extensions and codes its profile asks for.

ExportCopy Anchor Link

Each exporter takes a row as the block returns it and gives one resource. It reads only the fields it maps, so a Pick of the row is enough.

The subject of a resource is Patient/<subjectId> unless you pass subject. Users, such as the performer of an observation or the prescriber of an order, only appear when you pass user, a function from a user id to a reference:

const resource = toFhirObservation(observation, {
  definition,
  subject: { reference: `Patient/${patient.externalId}` },
  user: (userId) => ({ reference: `Practitioner/${userId}` }),
});

A care plan holds its problems as contained Condition resources and its goals as contained Goal resources, referenced as #<id>. Its actions become activity entries, an appointment action with kind Appointment and a task action with kind Task. Pass codeSystems to give each of the block's code systems a URI, such as { icf: "http://hl7.org/fhir/sid/icf-nl" }.

The output never holds an empty array or an empty object, which FHIR JSON forbids: a field without a value is left out.

BundlesCopy Anchor Link

toFhirBundle wraps resources in one Bundle. Pass baseUrl to give each entry a fullUrl. A transaction or batch Bundle gets a request per entry: a PUT to Type/id, or a POST to Type for a resource without an id. The Next.js example serves a customer's records as a Bundle:

export const GET = bsb.route<{ id: string }, true>(
  async (_request, { db, params }) => {
    const observations = await db.observations.list("customer", params.id);

    if (!observations.ok) {
      return observations;
    }

    const bundle = toFhirBundle(
      observations.data.map((observation) => toFhirObservation(observation)),
    );

    return Response.json(bundle, {
      headers: { "content-type": "application/fhir+json" },
    });
  },
  { requireTenant: true, permission: "customers.read" },
);

ImportCopy Anchor Link

fromFhirObservation and fromFhirMedicationRequest take an untrusted value, such as a parsed request body, and return a Result. They never throw: input that isn't a valid resource gives a validation error that lists every problem in issues.

const definitions = await db.observations.definitions(organizationId).orThrow();
const item = fromFhirObservation(body, { subjectType: "client", definitions });

if (item.ok) {
  await db.observations.ingest(organizationId, [item.data]);
}

Both need an id or identifier on the resource, which becomes the externalId, so importing the same resource twice records it once. The subject id comes from subject.reference unless you pass subjectId.