One of the assets that NHS Digital create for their “messaging” products in FHIR is called a MessageDefinition these are published on the NHS Reference Server where NHS Digital publish all of their FHIR profiling resources. NHS Digital has supercharged them from the standard FHIR offering by adding a few extensions. A tool that can be used for building the MessageDefinition files as used by NHS Digital is available here Tool : FHIR Message Definition Tool
These “assets” can be StructureDefinitions for Profiles or Extensions, ValueSets or CodeSystems – each is listed together with the version number.
The MessageDefinition resources contain a manifest of all the FHIR profile assets required to implement the message (over and above the base FHIR STU3 release). When looking at one the list can get very long indeed. For example, the “https://fhir.nhs.uk/STU3/MessageDefinition/ITK-eDischarge-MessageDefinition-Instance-1” message definition lists 294 assets in it’s manifest.
That is to say, to implement the Transfer of Care eDischarge solution there are 294 FHIR assets required. As useful as that is, that’s quite a lot of assets.
The FHIR STU3 related assets are all available as a single download from the FHIR STU3 site at their download page http://hl7.org/fhir/STU3/downloads.html the others are available from the FHIR Reference server but if you need/want them all, downloading them one at a time would be a chore.
So to address this, I have created another tool in the ClaroTech FHIR toolbox called the “PackageBuilder”. This tool will use the MessageDefinition file to identify all the assets that are not from the base standard, download them from the FHIR Reference Server (using its RESTful API) and then package them into a single ZIP file.
The tool is available now in the tools section of this site.