auth.md

Authentication to FHIR servers

You may want to use third-party authentication to access FHIR servers (e.g. for terminology servers). In this case, you can pass in the httpHeaders option.

For example, if in your application you use fhirclient npm-package, which sets the Authorization header for requests to the FHIR server, you can pass in the same header to fhirpath.js so that it can access the FHIR server with the same authorization:

FHIR.oauth2.ready().then(client => {
  const res = fhirpath.evaluate(
    {"resourceType": "QuestionnaireResponse", ...},
    '%context.repeat(item).answer.weight().sum()',
    {},
    fhirpath_r4_model,
    {
      async: true,
      terminologyUrl: 'https://some-server',
      httpHeaders: {
        'https://some-server': {
          // Use the same Authorization header as fhirClient
          Authorization: client.getAuthorizationHeader()
        }
      }
    }
  );
});

When the terminologyUrl option contains multiple servers (an array of URLs), add an entry to httpHeaders for each server base URL that requires authentication; the headers whose key matches the server being requested are applied automatically.