Implement FHIR Bulk Data $import to ingest large volumes of FHIR NDJSON resources into a FHIR server

In-depth guide

Steps

1. Confirm the target FHIR server supports $import by checking its CapabilityStatement or documentation; note that $import is a proposed operation and server support varies significantly
2. Stage the FHIR NDJSON files in a location accessible to the server (e.g., a cloud storage bucket with a pre-signed URL or a location the server can pull from)
3. Construct a Parameters body for the $import request specifying inputFormat (application/fhir+ndjson), inputSource (the base URL of the staged files), and storageDetail (type and credentials if needed)
4. POST to [base]/$import with Prefer: respond-async; expect a 202 Accepted with a Content-Location header for status polling
5. Poll the Content-Location URL; the server returns 202 with progress details until import completes, then 200 with a manifest describing success and error counts per resource type
6. Check the error output files in the manifest for rejected resources; parse each error NDJSON line which typically contains an OperationOutcome explaining the rejection reason