Filtering on Expand throws error

[sidharthramesh]

Sending the request:

curl -H "Accept: application/json" 'localhost:8080/fhir/ValueSet/$expand?url=http://snomed.info/sct?fhir_vs=ecl/<<50043002:<<263502005=<<19939008&filter=sili'

Returns:

{"resourceType":"OperationOutcome","issue":[{"severity":"error","code":"processing","diagnostics":"Failed to call access method: java.lang.NullPointerException: Query must not be null"}]}

Also, I've noticed that switching the order of the query parameters:

curl -H "Accept: application/json" 'localhost:8080/fhir/ValueSet/$expand?url=http://snomed.info/sct?filter=sili&fhir_vs=ecl/<<50043002:<<263502005=<<19939008'

Throws:

{"resourceType":"OperationOutcome","issue":[{"severity":"error","code":"processing","diagnostics":"Resource  is not known"}]}

Moreover, sometimes, the query might be URL encoded by some client libraries:
The conversion of

http://localhost:8080/fhir/ValueSet/$expand?url=http://snomed.info/sct?fhir_vs=ecl/<<50043002:<<263502005=<<19939008&filter=sili

would be

http://localhost:8080/fhir/ValueSet/$expand?url=http%3A%2F%2Fsnomed.info%2Fsct&fhir_vs=ecl%2F%3C%3C50043002%3A%3C%3C263502005%3D%3C%3C19939008

and this also throws:

{
  "resourceType": "OperationOutcome",
  "issue": [
    {
      "severity": "error",
      "code": "processing",
      "diagnostics": "Resource  is not known"
    }
  ]
}

Been learning some clojure in my free time. And I think the regex might be a reason for the Resource is not known error:

hades/src/com/eldrix/hades/convert.clj

Line 165 in 536c9ff

(let [[_ _ edition _ version query] (re-matches #"http://snomed.info/sct(/(\d*))?(/version/(\d{8}))?\?fhir_vs(.*)" uri)]

Not really sure regarding the null pointer. Seems like you are getting the filter parameter:

hades/src/com/eldrix/hades/core.clj

Line 116 in 536c9ff

^{:tag ca.uhn.fhir.rest.param.StringParam OperationParam {:name "filter"}} param-filter

But not sure how it's being used.

[wardle]

Personally I'd just use expand from Hermes. Why complicate by using FHIR as a transport?

[wardle]

Plus it has more sophisticated management of historical associations so that you can expand and include now thought to be outdated inactive concepts.

[sidharthramesh]

I'm mostly using FHIR terminology to use it alongside external applications like EHRBase.

[wardle]

I have restarted work on hades as I now need a generic FHIR terminology server myself! The plan is to have a plug gable architecture with Hermes being but one provider. Others will include FHIR bundles, CodeSystems and data marked up in CSVW for example.