Default or server-side generated values

[ErikSundvall]

During https://openehr.atlassian.net/wiki/display/spec/2016-06-30+REST+API+Meeting+notes I believe that @bjornna mentioned that one of their implementations added values (for example time-stamps) on the server-side if a mandatory field was missing.

Another option is to throw an error if mandatory things are missing. But some things (for example some timestamps) can be good to have an option to add server-side...

Yet another option could be to have some values/flags (either as metadata in the call header or some other place or inlined at places in the body) to explicitly ask the server to generate missing mandatory (and even some optional) values. A value of @now could for example be replaced with the server's current time.

Let the discussion begin...

[ppazos]

@ErikSundvall I should take a look to the code to have a full list of values injected by the server. One I remember is the composition uid, if that doesn't come from the client that commits the composition/version, the server generates and assigns an UUID to the composition.uid.

[bostjanl]

For the moment we only use canonical openEHR JSON format where the only value that is set by the server is UID (if not provided in the data).