WIP: Implement the ITI-48 transaction (Retrieve Value Set, SOAP)

[qligier]

This is an implementation of the IHE ITI-48 transaction, Retrieve Value Set, for the SOAP binding only. It introduces new modules: ipf-commons-ihe-svs and ipf-platform-camel-ihe-svs (SVS for Sharing Value Sets profile). Models for request and response are introduced, along with Camel converters. A simple validator (based on XSD) is implemented. The audit record messages are generated.

List of issues with the specification, and how I dealt with them:

1. In case of an error, the NAV and VERUNK codes can't be specified as a fault code, as per SOAP 1.2 specification. Instead, in the implementation, they're specified as fault subcode (without namespace) and the fault code is set to SENDER.
2. In the audit record messages (consumer and repository), there's a typo in the transaction name: Retrieve Value Sets instead of Retrieve Value Set (as it's used elsewhere in the specification). The implementation uses the latter.
3. In the audit record messages (consumer and repository), the participantObjectDetail contains the value set version and is mandatory on the repository side. In the DICOM specification, it's not a free text field but a type-value pair element. The specification does not define what value to use for @type; this implementation uses type="ValueSetVersion".

There are other small issues that are not preventing an implementation. Not sure if they are worth writing CPs.

[unixoid]

The long service creation time is most probably caused by the huge XML Schemas which contain ca. 27000 lines. We have had the same problem many years ago when implementing PIXv3/PDQv3 components.

[qligier]

I found the culprit. It wasn't the schema complexity but the following import in the schema:

<xs:import namespace="http://www.w3.org/XML/1998/namespace" schemaLocation="http://www.w3.org/2001/xml.xsd"/>

It was most probably hitting the HTTP request timeout, thus the constant 30 seconds delay.

I've nonetheless simplified the schema.

[unixoid]

FYI: we have a local copy of it in /commons/ihe/hl7v3/src/main/resources/schema.

[qligier]

It does not seem to be useful, the definitions are self-contained or come from the http://www.w3.org/2001/XMLSchema namespace, so I don't think we've a good reason to reintroduce it as a local import.

[unixoid]

@qligier: eHealth Suisse told us you need a new IPF release. No problem. But do you want this pull request to be part of it? If yes, please finalize it. :-)

[qligier]

Yes, it would be nice to start the eHealthConnector refactoring based on IPF 4.1

I've updated the only part of the code that I wanted to change but there's no urgency for this, at least on my side: we're manually including the code in one of our HUG project (so not waiting on a release), and I think SVS is out of scope of the eHC.
I've implemented as close as possible to the spec while fixing some of the issues, so it's not perfect but cannot be improved yet. I'm waiting for Lynn's answer about the specification issues and will fix the implementation once a change request is written or voted (no idea about the timeline).
So whether you want to merge it and open an issue to track IHE fixes on this or let it open and merge only when the implementation is compliant is up to you.

[unixoid]

@qligier: FYI: IPF 4.1.0 is released.

[qligier]

I've rebased the PR on top of master and fixed the parts that were not done yet. The PR should ultimately be ready for review.
Tests are passing, the CI fails submitting the dependency graph.

[unixoid]

Hello @qligier
Thank you for the contribution! I made some changes, added a Spring Boot starter and documentation.
Do I understand that you created JAXB stub classes and object factories manually instead of using xjc or wscompile?
And: can I close #458?

[qligier]

Hi @unixoid! Thank you for your work!

Yes, I wasn't pleased with the XSD provided by IHE. I took the decision to write the few classes needed by hand. And at the time of writing the JAXB factories, it was simpler to continue by hand than to find the rights commands to generate the schema from the classes, and then regenerate the classes with the factories from the schema.
Luckily, the SVS class hierarchy is really simple.

I also tweaked the XSD file to improve the validation coverage, and added the XML XSD because xml:lang was causing issues with the XSD validator.