WIP Issue 21

fhirpathpy/engine/evaluators/__init__.py

@@ -182,26 +182,37 @@ def func(acc, res):
             actualTypes = model["choiceTypePaths"][childPath]
 
         toAdd = None
+        toAdd_ = None
 
         if isinstance(actualTypes, list):
             # Use actualTypes to find the field's value
             for actualType in actualTypes:
                 field = key + actualType
-                if isinstance(res.data, (dict, list)) and field in res.data:
-                    toAdd = res.data[field]
-                    childPath = actualType
-                    break
+                if isinstance(res.data, (dict, list)):
+                    toAdd = res.data.get(field)
+                    toAdd_ = res.data.get(f"_{field}")
+                    if toAdd is not None or toAdd_ is not None:
+                        childPath = actualType
+                        break
         else:
-            if isinstance(res.data, (dict, list)) and key in res.data:
-                toAdd = res.data[key]
+            if isinstance(res.data, (dict, list)):
+                toAdd = res.data.get(key)
+                toAdd_ = res.data.get(f"_{key}")
+                if key == 'extension':
+                    childPath = 'Extension'
 
         if util.is_some(toAdd):
             if isinstance(toAdd, list):
                 mapped = [nodes.ResourceNode.create_node(x, childPath) for x in toAdd]
                 acc = acc + mapped
             else:
                 acc.append(nodes.ResourceNode.create_node(toAdd, childPath))
-            return acc
+        if util.is_some(toAdd_):
+            if isinstance(toAdd_, list):
+                mapped = [nodes.ResourceNode.create_node(x, childPath) for x in toAdd_]
+                acc = acc + mapped
+            else:
+                acc.append(nodes.ResourceNode.create_node(toAdd_, childPath))
         return acc
 
     return func
@@ -265,9 +276,7 @@ def polarity_expression(ctx, parentData, node):
     rtn = engine.do_eval(ctx, parentData, node["children"][0])
 
     if len(rtn) != 1:  # not yet in spec, but per Bryn Rhodes
-        raise Exception(
-            "Unary " + sign + " can only be applied to an individual number."
-        )
+        raise Exception("Unary " + sign + " can only be applied to an individual number.")
 
     if not util.is_number(rtn[0]):
         raise Exception("Unary " + sign + " can only be applied to a number.")
@@ -301,9 +310,7 @@ def polarity_expression(ctx, parentData, node):
     # expressions
     "PolarityExpression": polarity_expression,
     "IndexerExpression": indexer_expression,
-    "MembershipExpression": alias_op_expression(
-        {"contains": "containsOp", "in": "inOp"}
-    ),
+    "MembershipExpression": alias_op_expression({"contains": "containsOp", "in": "inOp"}),
     "TermExpression": term_expression,
     "UnionExpression": union_expression,
     "InvocationExpression": invocation_expression,

fhirpathpy/engine/invocations/__init__.py

@@ -27,6 +27,7 @@
     "count": {"fn": existence.count_fn},
     "repeat": {"fn": filtering.repeat_macro, "arity": {1: ["Expr"]}},
     "where": {"fn": filtering.where_macro, "arity": {1: ["Expr"]}},
+    "extension": {"fn": filtering.extension, "arity": {1: ["String"]}},
     "select": {"fn": filtering.select_macro, "arity": {1: ["Expr"]}},
     "single": {"fn": filtering.single_fn},
     "first": {"fn": filtering.first_fn},
@@ -42,8 +43,8 @@
     "toInteger": {"fn": misc.to_integer},
     "toDecimal": {"fn": misc.to_decimal},
     "toString": {"fn": misc.to_string},
-    # toDateTime:   {fn: misc.toDateTime},
-    # toTime:       {fn: misc.toTime},
+    "toDateTime": {"fn": misc.to_date_time},
+    "toTime": {"fn": misc.to_time},
     "indexOf": {"fn": strings.index_of, "arity": {1: ["String"]}, "nullable_input": True},
     "substring": {
         "fn": strings.substring,

fhirpathpy/engine/invocations/equality.py

@@ -35,9 +35,11 @@ def datetime_equality(ctx, x, y):
     datetime_x = x[0]
     datetime_y = y[0]
     if type(datetime_x) not in DATETIME_NODES_LIST:
-        datetime_x = nodes.FP_DateTime(datetime_x) or nodes.FP_Time(datetime_x)
+        v_x = util.get_data(datetime_x)
+        datetime_x = nodes.FP_DateTime(v_x) or nodes.FP_Time(v_x)
     if type(datetime_y) not in DATETIME_NODES_LIST:
-        datetime_y = nodes.FP_DateTime(datetime_y) or nodes.FP_Time(datetime_y)
+        v_y = util.get_data(datetime_y)
+        datetime_y = nodes.FP_DateTime(v_y) or nodes.FP_Time(v_y)
     return datetime_x.equals(datetime_y)
 
 

fhirpathpy/engine/invocations/filtering.py

@@ -1,5 +1,6 @@
 import numbers
 import fhirpathpy.engine.util as util
+import fhirpathpy.engine.nodes as nodes
 
 # Contains the FHIRPath Filtering and Projection functions.
 # (Section 5.2 of the FHIRPath 1.0.0 specification).
@@ -115,3 +116,14 @@ def check_fhir_type(ctx, x, tp):
 
 def of_type_fn(ctx, coll, tp):
     return list(filter(lambda x: check_fhir_type(ctx, util.get_data(x), tp), coll))
+
+
+def extension(ctx, data, url):
+    res = []
+    for d in data:
+        element = util.get_data(d)
+        if isinstance(element, dict):
+            exts = [e for e in element.get("extension", []) if e["url"] == url]
+            if len(exts) > 0:
+                res.append(nodes.ResourceNode.create_node(exts[0], "Extension"))
+    return res

fhirpathpy/engine/invocations/misc.py

@@ -96,7 +96,7 @@ def to_date_time(ctx, coll):
         dateTimeObject = nodes.FP_DateTime(value)
 
         if dateTimeObject:
-            rtn[0] = dateTimeObject
+            rtn.append(dateTimeObject)
 
     return rtn
 
@@ -113,6 +113,6 @@ def to_time(ctx, coll):
         timeObject = nodes.FP_Time(value)
 
         if timeObject:
-            rtn[0] = timeObject
+            rtn.append(timeObject)
 
     return rtn

tests/cases/extensions.yaml

@@ -0,0 +1,108 @@
+tests:
+  # https://www.hl7.org/fhir/fhirpath.html#types
+  - 'group: Extension and id for primitive types':
+
+    - desc: '** id for primitive type'
+      expression: Functions.attrtrue.id = 'someid'
+      result:
+        - true
+
+    - desc: '** expression with extension for primitive type 1'
+      inputfile: patient-example.json
+      expression: Patient.birthDate.extension.where(url = '').empty()
+      result:
+        - true
+
+    - desc: '** expression with extension for primitive type 2'
+      inputfile: patient-example.json
+      expression: >-
+        Patient.birthDate.extension
+        .where(url = 'http://hl7.org/fhir/StructureDefinition/patient-birthTime')
+        .valueDateTime.toDateTime() = @1974-12-25T14:35:45-05:00
+      result:
+        - true
+
+    - desc: '** expression with extension for primitive type 3'
+      inputfile: patient-example.json
+      model: r4
+      expression: >-
+        Patient.birthDate.extension
+        .where(url = 'http://hl7.org/fhir/StructureDefinition/patient-birthTime')
+        .value = @1974-12-25T14:35:45-05:00
+      result:
+        - true
+
+    # https://www.hl7.org/fhir/fhirpath.html#functions
+  - 'group: Additional functions':
+    - desc: 'extension(url : string) : collection'
+
+    # If the url is empty ({ }), the result is empty.
+    - desc: '** empty url'
+      inputfile: patient-example.json
+      expression: Patient.birthDate.extension('').empty()
+      result:
+        - true
+
+    # If the input collection is empty ({ }), the result is empty.
+    - desc: '** empty input collection'
+      inputfile: patient-example.json
+      expression: >-
+        Patient.birthDate1
+        .extension('http://hl7.org/fhir/StructureDefinition/patient-birthTime').empty()
+      result:
+        - true
+
+    - desc: '** expression with extension() for primitive type (without using FHIR model data)'
+      inputfile: patient-example.json
+      expression: >-
+        Patient.birthDate.extension('http://hl7.org/fhir/StructureDefinition/patient-birthTime')
+        .valueDateTime.toDateTime() = @1974-12-25T14:35:45-05:00
+      result:
+        - true
+
+    - desc: '** expression with extension() for primitive type (without using FHIR model data) when only extension is present'
+      inputfile: patient-example-2.json
+      expression: >-
+        Patient.communication.preferred.extension('test').exists()
+      result:
+        - true
+
+    - desc: '** expression with extension() for primitive type (using FHIR model data) when only extension is present'
+      inputfile: patient-example-2.json
+      model: r4
+      expression: >-
+        Patient.communication.preferred.extension('test').value.id
+      result:
+        - testing
+
+    - desc: '** expression with extension() for primitive type (using FHIR model data)'
+      inputfile: patient-example.json
+      model: r4
+      expression: >-
+        Patient.birthDate.extension('http://hl7.org/fhir/StructureDefinition/patient-birthTime')
+        .value = @1974-12-25T14:35:45-05:00
+      result:
+        - true
+
+    - desc: '** value of extension of extension (using FHIR model data)'
+      model: r4
+      expression: Functions.attrtrue.extension('url1').extension('url2').value = 'someuri'
+      result:
+        - true
+
+    - desc: '** id of extension of extension'
+      expression: Functions.attrtrue.extension('url1').extension('url2').id = 'someid2'
+      result:
+        - true
+
+subject:
+  resourceType: Functions
+  attrtrue: true
+  _attrtrue:
+    id: someid
+    extension:
+      - url: url1
+        extension:
+          - url: url2
+            id: someid2
+            valueUri: someuri

tests/resources/__init__.py

@@ -14,6 +14,7 @@ def save_to_resources(resources, resource_filename):
 
 save_to_resources(resources, "observation-example.json")
 save_to_resources(resources, "patient-example.json")
+save_to_resources(resources, "patient-example-2.json")
 save_to_resources(resources, "quantity-example.json")
 save_to_resources(resources, "questionnaire-example.json")
 save_to_resources(resources, "valueset-example-expansion.json")

tests/resources/patient-example-2.json

@@ -0,0 +1,26 @@
+{
+  "resourceType": "Patient",
+  "communication": [
+    {
+      "language": {
+        "coding": [
+          {
+            "system": "urn:ietf:bcp:47",
+            "code": "nl",
+            "display": "Dutch"
+          }
+        ]
+      },
+      "_preferred": {
+        "extension": [
+          {
+            "url": "test",
+            "_valueString": {
+              "id": "testing"
+            }
+          }
+        ]
+      }
+    }
+  ]
+}

tests/test_real.py

@@ -95,5 +95,37 @@ def pickle_test():
     assert reload(resource) == ["Patient/cdf"]
 
 
-
-
+def extension_test():
+    patient = {
+        "identifier": [
+            {
+                "period": {
+                    "start": "2020-01-01"
+                },
+                "system": "http://hl7.org/fhir/sid/us-mbi",
+                "type": {
+                    "coding": [
+                        {
+                            "code": "MC",
+                            "display": "Patient's Medicare number",
+                            "extension": [
+                                {
+                                    "url": "https://bluebutton.cms.gov/resources/codesystem/identifier-currency",
+                                    "valueCoding": {
+                                        "code": "current",
+                                        "display": "Current",
+                                        "system": "https://bluebutton.cms.gov/resources/codesystem/identifier-currency"
+                                    }
+                                }
+                            ],
+                            "system": "http://terminology.hl7.org/CodeSystem/v2-0203"
+                        }
+                    ]
+                },
+                "value": "7SM0A00AA00"
+            }
+        ],
+        "resourceType": "Patient"
+    }
+    result = evaluate(patient, "Patient.identifier.where(type.coding.extension('https://bluebutton.cms.gov/resources/codesystem/identifier-currency').valueCoding.code = 'current').where(system = 'http://hl7.org/fhir/sid/us-mbi').value")
+    assert result == ["7SM0A00AA00"]