Tool : Message Definition Tool
Functionality Overview
The FHIR Message Definition tool is used for creating message definitions as per the NHS Digital ITK specification. These detail the FHIR assets utilised within the message payload, including:
- Structure Definitions (Resources)
- Structure Definitions (Extensions)
- ValueSets
- CodeSystems
The tool will analyse the conformance resources of a FHIR message payload and traverse the resource reference, binding references etc to understand the total assets required to be understood by an implementer.
The tool is a console tool and is driven via a configuration file that controls the outputs of the tool. An example config file is shown below.
Resource Analysis Depth
Denotes whether the “core” FHIR resources should be included within the analysis or just the profiled resources.
Note – If the core resources are included (i.e. the value is true) then there is the potential for a very large output due to the way in which FHIR references between resources.
Extension Analysis Depth
Denotes whether the “core” FHIR extensions should be analysed or not.
Terminology Analysis Depth
Denotes whether the “core” FHIR terminology should be analysed or not.
Local Asset Store
The local directory where the FHIR conformance assets are stored. Any assets required that are not within this directory (or child directories) will be retrieved directly from the appropriate FHIR Reference sever.
Focus Profile(s)
A list of profiles (one or more) from which to start the recursive process of identifying the FHIR assets utilised within the message payload.
Note :
- This is a JSON array so entries should be separated by a comma
- This tool is intentionally limited to work on NHS Digital profile only.
Include CSV File Generation
Denotes whether a CSV file of the assets discovered should be created in addition to the “MessageDefinition” XML file.
Running the tool
The tool has been developed using .NET Core.
To run the tool:
- Download the tool (FREE) using the download links below
- Unpack the ZIP file
- Ensure you have created a config file as per the instructions above
- Open a Command Prompt in the directory where you have placed the tool
- Execute the tool as follows (assuming your config file is called ‘config.json’)
Tool Outputs
Message Definition file – messagedef.xml
The primary output of the tool is a FHIR MessageDefinition resource as per the NHS ITK3 specification. When produced this will be populated with details of all of the FHIR Constraint resources discovered by the tool.
FHIR Asset CSV file – messagedef.csv
If requested in the configuration file, the tool will output a “Comma Separated Values” file. This will be populated with details of all of the FHIR Constraint resources discovered by the tool.
Technology Inside
The TinderBox application was originally constructed as a test case for using FHIR Path and grew into something different altogether. The different technology components used within the application include:
Release History
The recent releases of the application include the following enhancements and fixes.