Stream: implementers
Topic: Instance Validation with HAPI FHIR
Claude Nanjo (Jan 29 2021 at 17:10):
Hello folks, does anyone have experience validating a FHIR instance (say a specific patient) against a 'home-made' (not US Core) profile programmatically (not via CLI)? If so, would you be able to share a code snippet on how to do that? I was hoping there would be a method such as validator.validate(myInstance, myProfile) or validator.validate(myInstance, myProfileURL) and if the latter, a way to register the profile with the FHIR context. Thank you!
Lloyd McKenzie (Jan 29 2021 at 22:03):
@Mark Iantorno
Mark Iantorno (Jan 29 2021 at 22:03):
hey
Mark Iantorno (Jan 29 2021 at 22:04):
What do you mean by "validate a FHIR resource programmatically" and not via the cli
Mark Iantorno (Jan 29 2021 at 22:04):
Validating a resource is huge
Mark Iantorno (Jan 29 2021 at 22:04):
Like...I can point you to the repository in GitHub where that code lives, but it is 100k+ lines of code
Lloyd McKenzie (Jan 29 2021 at 22:04):
I presume "how do you trigger validation from code" - is there documentation about how to instantiate the ValidationEngine and then trigger validation of an instance?
Mark Iantorno (Jan 29 2021 at 22:04):
@Claude Nanjo
Mark Iantorno (Jan 29 2021 at 22:05):
There is not documentation on that
Mark Iantorno (Jan 29 2021 at 22:05):
you would have to clone the repository and the write the call the method in the validation package
Mark Iantorno (Jan 29 2021 at 22:06):
I do this in the soon to be a real tool validation website, I can point you to that repo
Mark Iantorno (Jan 29 2021 at 22:06):
https://github.com/hapifhir/org.hl7.fhir.validator-wrapper is the project
Mark Iantorno (Jan 29 2021 at 22:07):
If you look at this class here: https://github.com/hapifhir/org.hl7.fhir.validator-wrapper/blob/master/src/jvmMain/kotlin/routes/ValidationRoutes.kt
Mark Iantorno (Jan 29 2021 at 22:08):
I create something called a ValidationRequest (https://github.com/hapifhir/org.hl7.fhir.validator-wrapper/blob/master/src/commonMain/kotlin/model/ValidationRequest.kt) and then send it to the Validator
Mark Iantorno (Jan 29 2021 at 22:09):
it contains the Validation CliContext, in addition to the list of files that need to be validated
Mark Iantorno (Jan 29 2021 at 22:09):
The CliContext contains all the information that a request for validation takes in
Mark Iantorno (Jan 29 2021 at 22:09):
it's named CliContext because I originally refactored it when only the Cli existed
Mark Iantorno (Jan 29 2021 at 22:10):
Take a look at that code, it should give you a starting point, but if you have other questions, let me know
Mark Iantorno (Jan 29 2021 at 22:17):
Also, in the core libs the ValidationService class is here: https://github.com/hapifhir/org.hl7.fhir.core/blob/master/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/cli/services/ValidationService.java
Claude Nanjo (Jan 29 2021 at 22:26):
James responded to my enquiry with the following recommendation which we are trying now:
There is an example of how to supply custom definitions to the validator here: https://hapifhir.io/hapi-fhir/docs/validation/validation_support_modules.html#recipe-supplying-custom-definitions
This example is actually a bit out of date, a new version is about to get pushed. You'll want to add the following two lines as well:
// This module supplies several code systems that are commonly used in validation
supportChain.addValidationSupport(new CommonCodeSystemsTerminologyService(ctx));
// This module implements terminology services for in-memory code validation
supportChain.addValidationSupport(new InMemoryTerminologyServerValidationSupport(ctx));
Mark Iantorno (Jan 29 2021 at 22:27):
So, just keep in mind that the HAPI validator does not align 100% with the core validator
Mark Iantorno (Jan 29 2021 at 22:27):
your results may vary
Mark Iantorno (Jan 29 2021 at 22:28):
So, you may have a resource that passes in HAPI but when run through the core validator, it fails
Mark Iantorno (Jan 29 2021 at 22:28):
or the other way around
Mark Iantorno (Jan 29 2021 at 22:28):
but they are _mostly_ aligned
Claude Nanjo (Jan 29 2021 at 22:28):
Thank you Mark. Sounds good. At some point, hopefully the two will converge.
Claude Nanjo (Jan 29 2021 at 22:29):
I will post our code once we verify it works for others who need to do the same thing.
Oliver Egger (Jan 30 2021 at 15:06):
@Claude Nanjo on the server se we implemented on top of hapi-fhir a $validate operation for both approaches and I think it might work similiar on the client side 1) hapi-fhir: https://github.com/ahdis/hapi-fhir-jpaserver-validator/blob/530/src/main/java/ch/ahdis/fhir/hapi/jpa/validation/ValidationProvider.java and 2) hapi-fhir but using directly the core validator: https://github.com/ahdis/matchbox/blob/master/src/main/java/ch/ahdis/matchbox/validation/ValidationProvider.java. @Mark Iantorno @James Agnew happy to provide a pull request on the base hapi-fhir implementation if this would be something of interest to you to add $valdiate operation (it is not 100% spec conform because it is on the root of the server and not on the resource).
Last updated: Apr 12 2022 at 19:14 UTC
