openMDWS: Transforming VistA Into An Open Source Service-Oriented Platform For Healthcare

Rob Tweed | The EWD Files | November 20, 2012

...The VA themselves have recognised this issue and have embarked on an ambitious project to identify VistA’s core functionality and make it available as a set of Web Services.  This initiative is known as Medical Domain Web Services (MDWS).  In my opinion, this is one of the single most important recent developments to take place within and around VistA: if successful, it will not only document and describe VistA’s core functionality, it will abstract that functionality as a set of services that can be used by any developer using any technology.  The need for specialised Mumps programming expertise to build upon VistA will potentially become a thing of the past.

However, there are a few key problems with the approach taken by the VA in developing MDWS:

  • the technical architecture makes use of and relies upon closed-source, proprietary technology.  MDWS is written using C# and .Net.  This makes it unacceptable to non-VA users of VistA who require a fully open-source stack and do not want to (or can’t) be dependent on Microsoft technologies...

...there is therefore a much better and more sensible architecture that can be used as the basis of MDWS.  Over the past few weeks I’ve been working on this and wish to announce what I am calling openMDWS.

openMDWS is designed to be a fully open source architecture that addresses all the issues I’ve described above.  It is completely compatible with and interoperable with the VA’s MDWS initiative, but will allow MDWS services to be developed and used on both Caché and GT.M systems, without requiring any additional technologies: openMDWS makes use of the natively-available stateless architecture in Caché and GT.M systems and also makes use of EWD for many of its core capabilities...