Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

FHIR RDF: More examples of polymorphic properties #3227

Open
wants to merge 4 commits into
base: master
Choose a base branch
from
Open

FHIR RDF: More examples of polymorphic properties #3227

Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
95e7480
Issue 138: Polymorphic primitive properties
dbooth-boston Nov 5, 2024
309f6be
Reword polymorphism and change predicate-->property
dbooth-boston Nov 12, 2024
315bc12
Edits from 14-Nov-2024 FHIR RDF call
dbooth-boston Nov 15, 2024
812c6c7
Merge branch 'HL7:master' into rdf-poly-primitive
dbooth-boston Nov 15, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
95 changes: 74 additions & 21 deletions source/rdf.html
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -62,9 +62,12 @@ <h2>Resource Description Framework (RDF) Representation </h2>
<li><a href="#resources">Representing Resources</a></li>
<li><a href="#caseSensitivity">Case Sensitivity</a></li>
<li><a href="#nestedNodes">Nested Anonymous Nodes</a></li>
<li><a href="#propertyNames">Property Names</a></li>
<li><a href="#propertyNames">Property Names and Polymorphism</a></li>
<li><a href="#rdflist">Representing Repeating Elements -- RDF Lists</a></li>
<li><a href="#primitive">Representing Primitive Elements</a></li>
<li><a href="#primitive">Representing Primitive Elements</a>
<ul>
</ul>
</li>
<li><a href="#reference">Representing References</a></li>
<li><a href="#contained">Representing Inline (Contained) Resources</a></li>
<li><a href="#representing-concepts">Representing Concepts</a></li>
Expand Down Expand Up @@ -141,7 +144,7 @@ <h3><a name="example"></a>FHIR RDF Example<br/>
PREFIX xsd: &lt;http://www.w3.org/2001/XMLSchema#&gt;
PREFIX owl: &lt;http://www.w3.org/2002/07/owl#&gt;

<span class="xmlcomment"> # Obs123 (subject) hasType (predicate) fhir:Observation</span>
<span class="xmlcomment"> # Obs123 (subject) hasType (property) fhir:Observation</span>
&lt;http://example.org/fhir/Observation/Obs123&gt; a fhir:Observation;
fhir:nodeRole fhir:treeRoot; <span class="xmlcomment"># (subject) is the serialization root of this document</span>
fhir:id [ fhir:v "Obs123" ]; <span class="xmlcomment"># (subject) has an id of "Obs123"</span>
Expand Down Expand Up @@ -183,7 +186,7 @@ <h3><a name="example"></a>FHIR RDF Example<br/>
<ul>
<li>the subject <a href="https://www.rfc-editor.org/rfc/rfc3987">IRI</a> is wrapped with '<code class="rdf">&lt; ... &gt;</code>'.</li>
<li>the type (<code class="rdf">fhir:Observation</code>) and
following predicates (e.g. <code class="rdf">fhir:status</code>)
following properties (e.g. <code class="rdf">fhir:status</code>)
are prefixed names (like XML namespaced names),</li>
<li>assertions following a ';' re-use the same subject,</li>
<li>anonymous nodes are declared with '<code class="rdf">[ ... ]</code>'s,</li>
Expand Down Expand Up @@ -232,11 +235,11 @@ <h4>Representing Resources</h4>

<a name="caseSensitivity"></a>
<h4>Case Sensitivity</h4>
<p> While RDF predicate names are case-sensitive, FHIR avoids
confusion by assuring that there are no predicates that
<p> While RDF property names are case-sensitive, FHIR avoids
confusion by assuring that there are no properties that
differ only in case. For example, there will be no <span
class="rdf">fhir:Code</span> predicate because there is
already a fhir:code predicate. <br/>
class="rdf">fhir:Code</span> property because there is
already a fhir:code property. <br/>
</p>

<a name="nestedNodes"></a>
Expand All @@ -258,23 +261,64 @@ <h4>Nested Anonymous Nodes</h4>
</ul>

<a name="propertyNames"></a>
<h4>Property Names</h4>
<p> A great deal of effort has gone into unifying FHIR
property names across resources and datatypes. These defined
properties effectively declare the FHIR RDF namespace with a
set of polymorphic, reuseable predicates. For example, <span
class="rdf">fhir:status</span> is spelled the same way
<h4>Property Names and Polymorphism</h4>
<p> Property names in FHIR RDF are shared across resources:
the same property may be used in several different resources.
For example, <span class="rdf">fhir:status</span> is spelled
the same way
regardless of whether it appears in an Observation,
Diagnosis, or any other FHIR Resource. </p>
<p> In other formats (XML, JSON), FHIR properties with choice
datatypes, like <span class="spec">value[x]</span>, are
appended with the datatype, e.g. <span class="json">valueQuantity</span>.
In RDF, this is written <span class="rdf">fhir:value</span>
<p> Some properties are polymorphic within a resource:
the property may offer a choice of more than one
permissible object type.

If the Structure tab in a resource's
HTML page shows "[x]" next to a property, such as
<span class="spec">value[x]</span> or
<a href="observation.html#resource">instantiates[x]</a>,
then that property is polymorphic in FHIR RDF.
(Alternatively, if the <code class="rdf">type</code>
property in the resource's structure definition shows
a list of two or more types for a given property's value,
then the property is polymorphic in FHIR RDF. For example, see the
<i>instantiates</i> property in
<a href="observation.profile.json.html">
Observation's structure definition</a>.)
In other formats (XML, JSON), a FHIR property with a choice
of value types has the value type appended to the property name,
e.g. <span class="json">valueQuantity</span>.
But in FHIR RDF, it is written as a polymorphic <span class="rdf">fhir:value</span> property,
and the object asserts its type explicitly, as in the <a href="#value">above
example</a>:<br/>
Observation example</a>:<br/>
</p>
<pre class="rdf"> fhir:value [ a fhir:Quantity; ... ]</pre>

<p> The <code class="rdf">fhir:instantiates</code> property in the
Observation resource is unusual in that its value may either
be the complex type <code class="rdf">fhir:Reference</code> or
the primitve type <code class="rdf">fhir:canonical</code>. But
in either case, the type is specified, such as:
</p>
<pre class="rdf">
&lt;Observation/123&gt;
fhir:instantiates [
a fhir:Reference ;
fhir:link &lt;http://example.org/fhir/PlanDefinition/KDN5&gt; ;
fhir:reference [
fhir:v "http://example.org/fhir/PlanDefinition/KDN5"^^xsd:anyURI
]
] ;
</pre>
<p>or:</p>
<pre class="rdf">
&lt;Observation/123&gt;
fhir:instantiates [
a fhir:canonical ;
fhir:link &lt;http://example.org/fhir/PlanDefinition/KDN5?version=v123&gt; ;
fhir:v "http://example.org/fhir/PlanDefinition/KDN5|v123"^^xsd:anyURI ;
] ;
</pre>

<a name="rdflist"></a>
<h4>Representing Repeating Elements -- RDF Lists</h4>
<p> Elements that can repeat are represented with <a href="https://www.w3.org/TR/turtle/#collections">RDF lists</a>
Expand All @@ -298,7 +342,7 @@ <h4>Representing Primitive Elements</h4>
extensions can be attached and so that they can consistently
be treated as OWL object properties (versus sometimes being datatype properties).&nbsp; The actual value of the
primitive type is represented as an RDF Literal using the <span
class="rdf">fhir:v</span> predicate.&nbsp; fhir:v is the
class="rdf">fhir:v</span> property.&nbsp; fhir:v is the
only FHIR property that directly holds an RDF literal -- i.e., it
is the only OWL datatype property in FHIR RDF -- and
it always holds an RDF Literal: </p>
Expand Down Expand Up @@ -343,6 +387,15 @@ <h4>Representing Primitive Elements</h4>
character of content. XHTML is represented as an escaped
xsd:string.&nbsp; <br/>
</p>

<pre class="rdf">
&lt;Observation/123&gt; fhir:instantiates [
a fhir:canonical ;
fhir:link &lt;http://example.org/fhir/PlanDefinition/KDN5?version=v123&gt; ;
fhir:v "http://example.org/fhir/PlanDefinition/KDN5|v123"^^xsd:anyURI ;
] ;
</pre>

<a name="reference"></a>
<h4>Representing References</h4>
<p> A <a href="references.html#Reference">Reference</a>
Expand Down Expand Up @@ -602,7 +655,7 @@ <h4>Modifier Extensions</h4>
</pre>

<p> BackboneElements and BackboneTypes are object types. Any
RDF predicate that references a modified BackboneElement or
RDF property that references a modified BackboneElement or
BackboneType is prefixed with a '_'. Note the underscore
at the beginning of "_value" in the following example:</p>
<pre class="rdf">&lt;http://example.org/fhir/Observation/Obs123&gt; a fhir:Observation;
Expand Down