Should URI to a ValueSet resolve to a valid end-point?

The goal is that the canonical url is a unique identifier for that ValueSet (or CodeSystem, or profile StructureDefinition, etc.). By "unique" I mean that the same url identifies the ValueSet regardless of what local FHIR server it is copied onto.

Because the primary use is as an identifier for the content, the canonical url doesn't have to resolve. It would be bad form (and I suspect against the spec) to use a url that you don't control; that is, unless you're Infoway, don't use a canonical url starting with infoway-inforoute.ca. And it would similarly be bad form to have the canonical url for a ValueSet resolve to a CodeSystem or to your company's investor relations web page, but I don't believe it is against the spec. There's a mix of approaches with some using fhir in the site name, others using it in the path, and others not including "fhir" at all; all are valid. If you're planning a large IG or multiple IGs you may want to partition your name space for ease of maintenance (mysite.ca/fhir/ig1/ValueSetA).

On the other hand, if you *can* set up your canonical urls so that they resolve to something useful, you're doing a great service to users of your spec, as it makes it easy to get more information about the resource in question.

If you have a domain, I would suggest going ahead and creating canonical urls for where you think you could post the content.

As a note, the general pattern is to use http rather than https for canonicals, since they are just identifiers, and for a similar reason, don't put a .html extension on the end (you'll set up your web server to redirect from mysite.ca/fhir/ValueSet/A to mysite.ca/fhir/ValueSet/A.html).

Elliot.

At least you have the domain registered. I'll try to see what can be done within the Ministry here. sigh....

Hi,

We ran into the same problem in Alberta. We have a bunch of OIDs that we created URIs for FHIR to use - but we don't have access to a server to host a resolvable address.

We did investigate with our services team, and it is potentially possible for us to get the URIs to be resolvable, but at present they are not.

We still have created our Provincial URIs using an Alberta base (fhir.alberta.ca), while those registered with HL7 international, we have tended to create in the Canadian FHIR Registry using the Canadian base.

Ideally, the URIs should be resolvable, but the reality is that many jurisdictions are in the same situation as Alberta and Quebec are, and this means that many URIs are going to act as you observed.

Randy

I'm new to FHIR and trying to understand something.

When in an implementation guide you're defining a ValueSet, say, you need to enter the canonical URI location.

I have seen many projects that provide a URI that either doesn't exist at all (the domain is not even registered) or the domain is registered but the actual end-point (the end page) is not available (so you get either a 503 or 404 HTTP code).

Is the actual idea to have a valid end-point where the users get more information about that ValueSet with some metadata (like history, types of values, specification, etc.) as well as the actual valueset, i.e., the list of values that should be used for that particular ValueSet?

We're working on a project and don't have a "home" yet for these end-points. In my view, these endpoints should be publicly facing (maybe behind some registration page) but should not be in an intranet (unless you know for a fact that nobody outside the intranet will require that information). So, if I don't have a "home" yet (registered DNS and full URI) what should I put for the canonical URL?

If I'm missing the point completely here, please let me know