HL7.CDSHooks.Domain 1.0.1

HL7 CDS Hooks Domain Objects

Release 2.0

https://cds-hooks.hl7.org/2.0/

JSON Rules

Use of JSON rules

Use of JSON

All data exchanged through production RESTful APIs MUST be sent and received as JSON (JavaScript Object Notation) structures and are transmitted over HTTPS. See Security and Safety section.

Null and Empty JSON Elements

• JSON elements SHALL NOT be null, unless otherwise specified.
• JSON elements SHALL NOT be empty, unless otherwise specified (e.g. to indicate no guidance with an empty array of cards in the CDS Hooks response).

If a JSON attribute is defined as OPTIONAL, and does not have a value, implementers MUST omit it. For instance, OPTIONAL JSON string and array attributes are omitted rather than having a null or empty value.

Unless otherwise specified, JSON attribute values SHALL NOT be null or empty, so null, "", [], or {} are prohibited. If a JSON attribute is defined as OPTIONAL, and does not have a value, implementers SHALL omit it.

CDS Card Models (CDS Service Response Object)

Card Attribute Docs

Namespace: HL7.CDSHooks.Domain.Models.Card

Examples:

var card = new CdsCard
{
    //Required
    Summary = "CDS Hook Card Response Example",
    Indicator = CardIndicatorTypes.Information,
    Source = new() //CdsSource
    {
        //Required
        Label = "Source Label",

        //Optional
        Icon = new("http://example.com/icon.png"), //Uri
        Url = new("http://learnmore.com"), //Uri
    },

    //Optional
    Uuid = Guid.NewGuid().ToString(),
    Detail = """
                **GitHub Flavored Markdown**
                       
                # Header
                > Sub-description n' stuff.
                       
                ## Items
                * First
                * Second
                * Third
             """,
    Links = [
        new()
        {
            Label = "Link Display Text",
            Url = "http://somelinktext.boom",
            Type = CardLinkTypes.Absolute
        }
    ]
};

HTTP Requests & Response Models

Discovery Endpoint Response

The response to the discovery endpoint SHALL be an object containing a list of CDS Services.

Discovery Response Doc

Namespace: HL7.CDSHooks.Domain.Models.Rest.Responses

var services = new CdsServiceDiscoveryResponse()
{
    Services =
    [
        new()
        {
            //Required
            Id = "0001",
            Description = "Say hello to patient from CDS Hook",
            Hook = CdsHooks.PatientView,

            //Optional
            Title = "SomeEHR Patient View CDS Hook",
            Prefetch = new Dictionary<string, string>
            {
                { "patient", "Patient/{{context.patientId}}" },
                { "conditions", "Condition?patient={{context.patientId}}" }
            }
        }
    ]
};

Feedback

 var feedback = new CdsFeedback
{
    //Required
    Card = "0001", // Card.Uuid the feedback is for
    Outcome = OutcomeTypes.Accepted, //Accepted of Overridden use constants to avoid errors
    OutcomeTimestamp = DateTime.UtcNow.ToISO8601Format(), //Use Extensions to maintain expected format.
};

Constants (Error Free value passing)

Namespace: HL7.CDSHooks.Domain.Constants

Hook Constants

Action Types

Card Attributes - Indicator Description Section

Link Types

Feedback Outcome Types