Resource identifiers
- Resource IDs MUST be generated only by FHIR server.
- Business ID-s MUST NOT be used as the resource ID.
- References between ReST resources SHOULD be literal references without FHIR server path but MAY be logical references.
- When using the FHIR ReST Paradigm, resources SHOULD reference other resources via URL (i.e. a literal reference in the FHIR standard). The resource owner should (where possible) only reference other resources that they can be relatively confident consumers of their API will be able to resolve and retrieve. For referencing other things outside this, a logical reference SHOULD be used.
- Note: URL references to other resources will (by default) return the latest version of the referenced resource. If this isn’t desirable, the resource owner may either contain the resource or use a versioned URL as a literal reference.
- References in FHIR messaging SHOULD be logical references.
- When using the FHIR Messaging Paradigm, messages will likely include references to external resources. These references SHOULD use an identifier from a known NamingSystem. This is known as a logical reference in the FHIR standard. The NamingSystem URI SHOULD be searchable on a FHIR Reference server to return the NamingSystem resource that describes the identifiers used (for example, https://fhir.hl7.ee/NamingSystem).