FHIR stores within the Cloud Healthcare API support a subset of the FHIR STU3 (Fast Healthcare Interoperability Resources, Release 3 - Standard for Trial Use) specification published by HL7 (Health Level 7 International). In general, the server's capability statement indicates parts of the specification that are supported.
Supported functionality includes:
- Storage and retrieval of all STU3 resources, including support for extension elements.
- All of the methods in the RESTful API, except for:
- All of the search
functionality, except for:
- The search parameters
Bundle-messageare not supported. Search parameters defined on extension elements are not supported.
- The search result parameters
_summary=trueare not supported.
- The special search parameters
_filterare not supported.
_sortparameter, when used on fields with repeated elements, sorts by the first element; this differs from the specification. All supported search parameters are eligible for
_sort, except for the special search parameter
- The search parameters
Areas that are not currently supported include:
- Most extended operations are not implemented.
- Profiles are not validated or enforced by the server.
- User-defined search parameters are not supported.
In general, missing or non-standard API functionality at this stage of development should not necessarily be interpreted as a final design decision.
Some areas where the API contains operations outside of the published specification include:
- The FHIR gRPC API offers an RPC interface for FHIR using the gRPC framework. It is nonstandard, under development, and does not support all FHIR methods.
- The FHIR store configuration includes an option to notify a user-specified Cloud Pub/Sub topic for all changes to resources in the store. This notification mechanism is common across all Cloud Healthcare API stores, and is not intended as a replacement for FHIR Subscription functionality.
- The FHIR store export operation to Cloud Storage destinations offers only a bulk export of the entire store. It is not an implementation of the FHIR Bulk Data draft specification.
- The FHIR store import operation is not defined in the specification.
Resource-purgeoperation that removes historical versions of resources is not defined in the specification. This API could change in the future if the standards process or other FHIR implementations converge on a different API method for this use case.