Stream: subscriptions
Topic: SubscriptionTopic
Grahame Grieve (Feb 03 2020 at 02:38):
@Gino Canessa I've managed to get to actual connectathoning and I've been talking to @Jenni Syed about the SubscriptionTopic resource, specifically the canFIlterBy bit
Grahame Grieve (Feb 03 2020 at 02:39):
I found it obtuse around canFilterBy, how the filters work. The definition specifically says that it's 'search parameters', but the definitions of the match types confuse the issure
Grahame Grieve (Feb 03 2020 at 02:40):
I'd like to be able to pass filter parameters into fhirpath expressions as well.
Grahame Grieve (Feb 03 2020 at 02:41):
with that in mind, it would be good if you could have more than one FHIRPath expression, so that you could have iff(%parameter.exists()).else() etc without having to have on massive complicated one
Grahame Grieve (Feb 03 2020 at 02:41):
and if we could clearly say just what the expectations are here. Obviously there's 2 disparate interests: what are the filters you can use in a subscription (which we all share) and how do they actually work (which a subset of servers are interested in, including mine)
Grahame Grieve (Feb 03 2020 at 02:43):
another related question: the implementation parts of subscription topic can get complicated once you start dealing with the create/update/delete, even if their surface is similar. I'm wondering whether there's a need/space for doing something about this to have different implementation details for filter parameters depending on method?
Grahame Grieve (Feb 03 2020 at 02:45):
even if you (like Isaac) aren't sure about the merits of passing variables to FHIRPath expressions, I think that generically a server is going to have some criteria that are done well at the index level and others that are done well at the instance level
Jenni Syed (Feb 03 2020 at 02:45):
For the method specifics - we had some discussion around that specifically about delete... I need to confirm where it landed
Jenni Syed (Feb 03 2020 at 02:46):
@Grahame Grieve What is an example of something that you would like the parameters in fhirpath vs. where it can't be done (or it's not clear it can be done) today?
Gino Canessa (Feb 03 2020 at 02:47):
Yes, this has been a complicated area to balance: the more flexible we make the base, the more complicated it is to implement.
Gino Canessa (Feb 03 2020 at 02:48):
For the multiple expressions, do you have any ideas on how to do multiple simply? I was initially figuring multiple would be and/or, but in your case you're looking for an else
Grahame Grieve (Feb 03 2020 at 02:50):
multiple expressions - all must be true.
Grahame Grieve (Feb 03 2020 at 02:50):
or any must be true - it just flips the way you write them
Gino Canessa (Feb 03 2020 at 02:51):
Yes, we have been trying to avoid making the definitions too complicated (e.g., having another field specifying and vs or)
Grahame Grieve (Feb 03 2020 at 02:51):
Jenni - examples: anything for which there isn't a search parameter is something you can't do
Grahame Grieve (Feb 03 2020 at 02:52):
right. So just pick one - my point is, you can write the expressions to meet whatever we pick
Gino Canessa (Feb 03 2020 at 02:54):
re: canFilterBy: is there a language that can be used to specify subsets for fhirPath easily? We want to make sure committing to support of a topic doesn't balloon into supporting all kinds of chaining and paths
Gino Canessa (Feb 03 2020 at 02:55):
re: multiple fhirPath: works for me. I've added to my notes for the next pass of discussion and updates
Grahame Grieve (Feb 03 2020 at 02:56):
http://hl7.org/fhir/fhirpath.html#simple - but also, no resolve()
Grahame Grieve (Feb 03 2020 at 02:57):
we can start with that and relax things as we need, maybe
Gino Canessa (Feb 03 2020 at 02:58):
Looks good to work from
Grahame Grieve (Feb 03 2020 at 03:00):
well, good, but chaining and paths is something that's more seriously a problem for the search parameters, - that's also something that isn't talked about
Gino Canessa (Feb 03 2020 at 16:02):
Yep... it's something we've discussed, but hadn't necessarily resolved yet either.
Vassil Peytchev (Feb 03 2020 at 16:15):
It sounds like until there is a reasonable approach for chaining and paths for search parameters, SubscriptionTopic should avoid trying to include it for now. Or is there an argument to try to address chaining and paths in parallel for search parameters and ST?
Gino Canessa (Feb 03 2020 at 16:17):
Not that I'm aware of. The challenge has been how to specify and what the exact exclusions are.
Last updated: Apr 12 2022 at 19:14 UTC
