Reading FHIR resource history - AWS HealthLake
Reading version-specific history

Reading FHIR resource history

The FHIR history interaction retrieves the history of a particular FHIR resource in a HealthLake data store. Using this interaction, you can determine how the contents of a FHIR resource have changed over time. It is also useful in coordination with audit logs to see the state of a resource before and after modification. The FHIR interactions create, update, and delete result in a historical version of the resource to be saved. For additional information, see history in the FHIR R4 RESTful API documentation.

Note

You can opt out of history for specific FHIR resource types. To opt out, create a case using AWS Support Center Console. To create your case, log in to your AWS account and choose Create case.

To read FHIR resource history

  1. Collect HealthLake region and datastoreId values. For more information, see Getting data store properties.

  2. Determine the type of FHIR Resource to read and collect the associated id value. For more information, see Resource types.

  3. Construct a URL for the request using the collected values for HealthLake region and datastoreId. Also include the FHIR Resource type, its associated id, and optional search parameters. To view the entire URL path in the following example, scroll over the Copy button.

    GET https://healthlake.region.amazonaws.com/datastore/datastoreId/r4/Resource/id/_history{?[parameters]}
    HealthLake supported search parameters for FHIR history interaction
    Parameter Description
    _count : integer The maximum number of search results on a page. The server will return the number requested or the maximum number of search results allowed by default for the data store, whichever is lower.
    _since : instant Only include resource versions that were created at or after the given instant in time.
    _at : date(Time) Only include resource versions that were current at some point during the time period specified in the date time value. For more information, see date in the HL7 FHIR RESTful API documentation.

  4. Send the request. The FHIR history interaction uses a GET request with either AWS Signature Version 4 or SMART on FHIR authorization. The following curl example uses the _count search parameter to return 100 historical search results per page for a FHIR Patient resource in HealthLake. To view the entire example, scroll over the Copy button.

    curl

    SigV4 authorization

    curl --request GET \
  'https://healthlake.region.amazonaws.com/datastore/datastore-id/r4/Patient/id/_history?_count=100/ \
  --aws-sigv4 'aws:amz:region:healthlake' \
  --user "$AWS_ACCESS_KEY_ID:$AWS_SECRET_ACCESS_KEY" \
  --header "x-amz-security-token:$AWS_SESSION_TOKEN" \
  --header 'Accept: application/json'

    The return content of a history interaction is contained in a FHIR resource Bundle, with type set to history. It contains the specified version history, sorted with oldest versions last, and includes deleted resources. For more information, see Resource Bundle in the FHIR R4 documentation.

Reading version-specific FHIR resource history

The FHIR vread interaction performs a version-specific read of a resource in a HealthLake data store. Using this interaction, you can view the contents of a FHIR resource as it was at a particular time in the past.

Note

If you use FHIR history interaction without vread, HealthLake always returns the latest version of the resource's metadata.

HealthLake declares it support for versioning in CapabilityStatement.rest.resource.versioning for each supported resource. All HealthLake data stores include Resource.meta.versionId (vid) on all resources.

When FHIR history interaction is enabled (by default for data stores created after 10/25/2024 or by request for older data stores), the Bundle response includes the vid as part of the location element. In the following example, the vid displays as the number 1. To view the full example, see Example Bundle/bundle-response (JSON).

"response" : {
    "status" : "201 Created",
    "location" : "Patient/12423/_history/1",
    ...}
To read version-specific FHIR resource history

  1. Collect HealthLake region and datastoreId values. For more information, see Getting data store properties.

  2. Determine the FHIR Resource type to read and collect associated id and vid values. For more information, see Resource types.

  3. Construct a URL for the request using the values collected for HealthLake and FHIR. To view the entire URL path in the following example, scroll over the Copy button.

    GET https://healthlake.region.amazonaws.com/datastore/datastoreId/r4/Resource/id/_history/vid

  4. Send the request. The FHIR history interaction uses a GET request with either AWS Signature Version 4 or SMART on FHIR authorization. The following vread interaction returns a single instance with the content specified for the FHIR Patient resource for the version of the resource metadata specified by the vid. To view the entire URL path in the following example, scroll over the Copy button.

    curl

    SigV4 authorization

    curl --request GET \
  'https://healthlake.region.amazonaws.com/datastore/datastore-id/r4/Patient/id/_history/vid \
  --aws-sigv4 'aws:amz:region:healthlake' \
  --user "$AWS_ACCESS_KEY_ID:$AWS_SECRET_ACCESS_KEY" \
  --header "x-amz-security-token:$AWS_SESSION_TOKEN" \
  --header 'Accept: application/json'