Today’s HL7 UK connectathon was a first for many of the participants. It was certainly the first European hackathon and for most the first time working with FHIR. For many it was also a renewed acquintance with HL7, especially in the mobile and REST space. “Where were you when we needed you” pretty much sums up the general sentiment, as quite a few participants had resorted to build a home-brewn solution in the past years when requirements asked for a web-ready architecture. I am grateful that the participants took the effort to come to London today to ponder and try replacing their bespoke solutions for a FHIR based one.
Some things I wish to share:
- Robert Worden built a cross-server search client, that took your query, posted it to the available public servers, and then showed the combined result. Ofcourse, since the query format has changed from FHIR 0.11 (“Boston”) to FHIR 0.12 (“San Antonio”) this didn’t always work out yet, but nice to be able to do in just a day!
- Two colleagues from the NHS Wales split the work: one built a FHIR adapter on top of v2 PDQ, while the other tried to invoke that service from a set of collaborating Android apps. It showed again that turning a v2 message into a REST resource requires careful thought about how you go about managing REST identities in relation to the available business keys.
- Robert and his colleague Mark have been working on putting a FHIR wrapper on top of an existing database. Robert, as would be expected, built a mapping tool for this! Practical problem here is that they had a database without primary keys and no timestamping whatsoever. In addition the schema was fixed and the database read-only. Under these circumstances it’s hard to come up with a method to have a reliable version id to use as a FHIR version id, even when you’re allowed to only keep the most recent version.
- Richard and Prashant of the NHS are all set to start using the full Profile and Conformance infrastructure (REST based validation, Profile editor, automated conformance testing). On their wishlist: a Profile to XSD converter. And documentation of how to create your own Resource (which, of course, is an unsupported practice anyway ;-))
- There were many Json users, yet no one used Json schema. Which is a good thing, since our latest Json serialization format does not really lend itself to such validation.
- Vendors working with the NHS are comfortable with the fact they might have to use FHIR for some of the upcoming exchanges. For some, however, the fact that FHIR is an HL7 product seems to take away some of that cautious enhousiasm. Clearly, we’ll have to work on our reputation here!
As usual the hours passed by in the blink of an eye, accompanied by the comforting sound of a humming airco and the hammering of keys. That’s how I like my hackathons!