Take a ride
Firely has built a new FHIR Server named Vonk. In keywords: enterprise grade, support available, SQL Server and MongoDB, FHIR Facade, cross-platform, Dockerized, .Net Core, STU3. As of now it is in public Beta. Try it at http://vonk.fire.ly or download a trial at Simplifier.
This is my bike. After being a simple city bike for the first 25 years, I decided to keep the good parts and improve the rest. Now it suits all my many bike needs. It is clean. No gears, no cables, no chain cover, just the items that I really need. It is strong but not heavy. Steel frame, steel carrier, able to carry my wife on a romantic trip and it doesn’t break on the many potholes and loose tiles in the city. It is versatile. It can ride both dirt- and tarmac roads. Run lightly on my way to work, carry all the groceries for a week on Friday. It has the right size. Large enough for my 1.95m length, but it still easily fits in a bicycle rack. It never gets in my way in the shed. Maybe the best part is the carbon belt drive that I had mounted recently. Unbreakable and yet free of maintenance. And now that the bike is 27 years old and still my daily commuting bike I can faithfully say that it’s proven technology. And my inspiration for developing Vonk.
The old bike
Back in 2012 when FHIR had just started, Firely started implementing the server part of the specification in .Net, and we called it Spark. A reference implementation to test the spec and provide the world with a real FHIR server to develop and test against. It has gained a lot of attraction, well beyond these purposes. Many requests for e.g. production use, SQL Server, STU3 and company support reached us.
The new bike
So we decided to respond with a new incarnation of Spark that would be able to serve as a very versatile yet production ready FHIR server. And it deserved it’s own name: Vonk. Vonk packs together our extensive experience with FHIR, the HL7 FHIR .Net library and Spark in a fully new solution based on Microsoft .Net Core.
Several of you may have seen my talk on building a FHIR Server (> 19:30) at FHIR DevDays last November. By now we have realized many of the ideas that I presented in that talk. As of today we present the official Beta release of Vonk.
Ready to ride
My bike is always ready to ride. For a quick schoolrun or an extended birdwatching ride – it will just run. Vonk FHIR Server is the same. Install and run. It is a stand alone FHIR server with MongoDB storage. Or SQL Server and then truly support transactions. Or run a few quick tests on the in-memory store. The storage API that we created to accommodate these very different storage engines enables us to add other other back ends easily, either with or without support of Entity Framework.
Change the wheels
A few weeks ago my birdwatching buddy lured me into a dirt road. Dirt became mud and then deep mud. Even my bike has limits. It meant I had to continue walking. But with Vonk you just change the wheels! With Vonk FHIR Facade you can leverage the power of the storage API to plug it on top of your existing database. Thus Vonk acts as a FHIR REST facade on top of your (legacy) system. And although Vonk is enterprise grade, it is not heavy. So you can unleash your systems small and large all in the same way. All you need to do is create an implementation of the storage abstraction for your use case. We already did so ourselves: the Simplifier.net platform runs on Vonk. The same abstraction even allows you to address other (web) services for retrieving or storing the actual data, thereby using Vonk as a hub, possibly backed by other Vonk instances that are facades to your internal systems. When creating a facade you program the new wheels in .Net, with all the power that comes with that. On the roadmap is creating facades by configuration.
Assemble your own
No gears, no handbrakes, clean as can be. But a bit too clean if you need to climb a hill. In the Netherlands we don’t do hills, but Vonk can be used around the globe. Vonk FHIR Components gives you all the good parts of Vonk, for you to assemble your own perfect FHIR Server. Or integrate it into a larger web server. Or turn it into a hometrainer. Just add and leave out parts as you like. Vonk FHIR Components will become available as NuGet packages.
Run all the tasks you need
From groceries to commuting: even my bike is not as versatile as Vonk. In this beta release it will do STU3 and DSTU2, JSON and XML, and most of the regular FHIR interactions plus a few bonus ones:
- capability statement (metadata)
- create, read, update, delete
- search on all specified parameters, also chained, choices, multiple resource types, include related resources
- full resource version management, enabling history on resource, resource type and system level
- process batches of interactions, in a transaction if you wish (requires transactional storage)
- validate a resource against the spec or a custom profile
- extensible to custom operation (‘$your-operation’)
The road ahead
More features are on their way. Priority is volatile and can be influenced by customer requests.
- support for several more options, e.g. _summary, _elements and conditional operations
- documents ($document)
- proper support for ‘Binary’ resources
Security in Amsterdam is not about riding with a helmet, but putting at least two solid locks on your bike. We know a thing or two about not letting your bike get stolen. Or your data. So Vonk runs on https, can be fronted by a reverse proxy (e.g. Apache or NGINX) and exposes just the FHIR RESTful API endpoints. But a fully locked bike brings you nowhere. You need access, but limited access if needed. Therefore Vonk can participate in an OAuth2 single sign-on environment. Access to resources can be based on the claims in the OAuth2 access token. You can use the preconfigured scopes and launch contexts as defined by SMART-on-FHIR, or configure your own.
Although my bike won’t ride on water (in Amsterdam we have canalbikes for that) or deep mud, just about any other surface will do. And Vonk is no different: it runs on Windows, Linux, OSX, as an executable or in a Docker container, on premise or in the cloud, as an Azure App Service – you choose.
When my colleague Marco showed me Vonk running on Docker I was so thrilled I even overtook e-bikes at 30 km/h on my way home. With Vonk we also made performance a number one priority. Using the newest Microsoft ASP.Net technology and proven storage solutions we managed to implement a very performant FHIR Server. Being lightweight and fully asynchronous you can scale out or up as you see fit.
Be in control
In the Netherlands there is wind. Usually in your face. You need to lie low. So my first upgrade was the handlebar that allows me to lie comfortably on it and still keep control over the bike. Extensive semantic logging to just about any target and a connection to Microsoft Application Insights allows you to control Vonk just as well. Integrated validation can be used as a gatekeeper to accept only compliant resources. On the roadmap is also an extensible management API to:
- add profiles, or restrict to specific profiles
- add or restrict the search parameters
- enable or disable operations
Where is the blueprint?
I’d be happy to tell you how I built this bike. But Vonk is not open source. Vonk is a commercial product based on license fees and paid support. Nevertheless we want to continue to support the FHIR community as we already do with the FHIR .Net API and Forge. In short it is possible to use Vonk for free if you support the FHIR community in any way with that usage. Just contact us to see if you’re proposed usage fits this goal.
What happens to the old parts?
I kept them in my shed as spares. As for Spark: This is up to the community. Firely has put a lot of effort in Spark and provides all of this effort to the community. It’s open source, available on GitHub. But Firely will neither port Spark to STU3 nor provide support for DSTU2.
I never gave my bike a name. But ‘Vonk’ means two things. First, it is the Dutch word for Spark. After struggling with our company name Firely we thought the FHIR community was up for the next Dutch challenge. Second it reminds us of our dear collegue Hans Vonkeman who has passed away far too young and thus it is a kind of a tribute.
And now I’ve been at the keyboard long enough. Off for a ride. Do you ride along? Visit the getting started to see how you can get a trial Vonk FHIR Server as binaries or in a Docker container.
Prefer to ride along face to face? I’ll be at the HL7 WGM in Madrid next week, albeit not by bike. Or visit the FHIR DevDays here in Amsterdam in November. There I will be by bike.