FHIR Chat · Serializing error

Stream: dotnet

Topic: Serializing error

Dennis Brox (Feb 21 2022 at 02:04):

When creating a Person resource, I can do the following:

        Period period = new Period()
        {
            Start = DateTime.MinValue.ToString(),
            End = DateTime.MaxValue.ToString()
        };
        var address = new Address()
        {
            . . . ,
            Period = period
        };

to set the Person address. If I then use FHIRserialize to serialize the resource and then use a FhirJsonParser to recreate the patient, I get an
error thrown indicating it can't deserialize the period I set. What's wrong with the period?

Dennis Brox (Feb 21 2022 at 07:25):

Forget this. Got it working by just forcing the date format to the FHIR standard. It was confusing when an error doesn't get thrown on the serialize - - not nice to be able to create garbage and not know about it until you try to read it back.

Brian Postlethwaite (Feb 21 2022 at 07:51):

There's an extension method .ToFhirDate() that you can use for those conversions.

Dennis Brox (Feb 21 2022 at 22:23):

Maybe this is the same type of problem but more severe. Using code:

            var serializer = new FhirJsonSerializer();
            var jo = serializer.SerializeToString(o);

            var parser = new FhirJsonParser();
            o =  parser.Parse<Observation>(jo);

You can see what gets serialized:
jo
"{\"resourceType\":\"Observation\",\"id\":\"f6174e82-f7f5-4ee0-ae61-1c37882bb27d\",\"text\":{\"div\":\"<xml><value>blood pressure</value></xml>\"},\"subject\":{\"reference\":\"52095\"},\"effectiveDateTime\":\"2022-01-16T11:28:16+00:00\",\"component\":[{\"code\":{\"text\":\"Systolic blood pressure\"},\"valueDecimal\":130},{\"code\":{\"text\":\"Diastolic blood pressure\"},\"valueDecimal\":80}]}"

And I get the following error i.e. it won't deserialize, whereas of course it works fine where there are no FHIR types.

Hl7.Fhir.ElementModel.StructuralTypeException
HResult=0x80131537
Message=Type checking the data: Choice element 'valueDecimal' is suffixed with unexpected type 'decimal' (at Observation.component[0].valueDecimal[0])
Source=Hl7.Fhir.Support

Michele Mottini (Feb 21 2022 at 22:46):

Yes, decimal is not a valid type for component.value, and the serializer does not check those things, it serializes whatever type it finds in the class (...and there is no easy C# way to prevent the assignment in the first place, that would be the 'right' solution)

Brian Postlethwaite (Feb 21 2022 at 22:52):

Yup, in Observation you're meant to use Quantity for numeric data (so that you apply the appropriate units too)

Dennis Brox (Feb 22 2022 at 01:45):

But the problem is that in component.value it is valueQuantity that must be used and it is a Quantity. In Quantity, value is decimal and nothing else can be entered except FHIRDecimal ?

Brian Postlethwaite (Feb 22 2022 at 03:44):

That's correct.

Brian Postlethwaite (Feb 22 2022 at 03:47):

Your example above just had decimal in the component.value, not in component.valueQuantity.valueDecimal

Last updated: Apr 12 2022 at 19:14 UTC

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FHIR Chat · Serializing error · dotnet