aehrc/smart-forms-extract repository overview

⁠SDC StructureMap-based $extract ExpressJS service POC

A ExpressJS⁠ Typescript reference implementation of the $extract⁠ operation from the HL7 FHIR Structured Data Capture Specification⁠. It is an abstraction on top of an existing StructureMap $transform⁠ operation to perform the extraction.

Brian Postlethwaite has a .NET mapping engine containing a proof-of-concept StructureMap $transform from https://github.com/brianpos/fhir-net-mappinglanguage/tree/main/demo-map-server⁠ which be deployed as a $transform operation on a microservice.

A StructureMap/$convert operation is also defined in the POC implementation to convert a FHIR Mapping Language map to a StructureMap resource, using the same .NET mapping engine.

⁠Docker Usage

Run docker run -p 3003:3003 -e EHR_SERVER_URL= aehrc/smart-forms-extract.

(Ensure that your FHIR server has a StructureMap $transform operation!)

By default, FORMS_SERVER_URL is set to https://smartforms.csiro.au/api/fhir⁠ in the Docker image. This endpoint is used to resolve referenced FHIR Questionnaires and StructureMaps.

⁠Optional environment variables

EHR_SERVER_URL

EHR_SERVER_AUTH_TOKEN

FORMS_SERVER_URL

FORMS_SERVER_AUTH_TOKEN

If you are planning to deploy this as a microservice on your EHR server, it is required for your EHR server to have a StructureMap $transform operation defined.

If EHR_SERVER_URL is left empty, the service will use the request endpoint as the EHR server URL. i.e. Deploying this service on http://localhost:3003/fhir⁠ will result in a call to http://localhost:3003/fhir/StructureMap/$transform⁠ during execution of the $extract operation.

⁠Sample implementation

As of 1 July 2025, we have decommissioned the $extract sample implementation. Please visit https://dev.fhirpath-lab.com/Questionnaire/tester⁠ which provides a .NET implementation of the $extract operation when testing extractable questionnaires.