Drivers License Feature (#113)

## Description
Add a new Feature to run comparisons on driver's license numbers.

## Related Issues
closes #95 

## Additional Notes

src/recordlinker/hl7/fhir.py

@@ -27,13 +27,21 @@ def fhir_record_to_pii_record(fhir_record: dict) -> schemas.PIIRecord:
         "race": None,
         "gender": None,
         "telecom": fhir_record.get("telecom", []),
+        "drivers_license": None,
     }
     for identifier in fhir_record.get("identifier", []):
         for coding in identifier.get("type", {}).get("coding", []):
             if coding.get("code") == "MR":
                 val["mrn"] = identifier.get("value")
             elif coding.get("code") == "SS":
                 val["ssn"] = identifier.get("value")
+            elif coding.get("code") == "DL":
+                license_number = identifier.get("value")
+                authority = identifier.get("assigner", {}).get("identifier", {}).get("value")  # Assuming `issuer` contains authority info
+                val["drivers_license"] = {
+                    "value": license_number,
+                    "authority": authority
+                }
     for address in val["address"]:
         address["county"] = address.get("district", "")
         for extension in address.get("extension", []):
@@ -53,7 +61,7 @@ def fhir_record_to_pii_record(fhir_record: dict) -> schemas.PIIRecord:
                 if ext.get("url") == "value":
                     for coding in ext.get("valueCodeableConcept", {}).get("coding", []):
                         val["gender"] = coding.get("display")
-
+    
     return schemas.PIIRecord(**val)
 
 def add_person_resource(

src/recordlinker/schemas/pii.py

@@ -29,6 +29,7 @@ class Feature(enum.Enum):
     TELEPHONE = "TELEPHONE"
     SUFFIX = "SUFFIX"
     COUNTY = "COUNTY"
+    DRIVERS_LICENSE = "DRIVERS_LICENSE"
 
     def __str__(self):
         """
@@ -133,10 +134,19 @@ class Telecom(pydantic.BaseModel):
 
     model_config = pydantic.ConfigDict(extra="allow")
 
-    value: str  # future use
+    value: str
     system: typing.Optional[str] = None
     use: typing.Optional[str] = None
 
+class DriversLicense(pydantic.BaseModel):
+    """
+    The schema for a Drivers License record
+    """
+
+    model_config = pydantic.ConfigDict(extra="allow")
+
+    value: str
+    authority: str
 
 class PIIRecord(pydantic.BaseModel):
     """
@@ -157,6 +167,7 @@ class PIIRecord(pydantic.BaseModel):
     ssn: typing.Optional[str] = None
     race: typing.Optional[Race] = None
     gender: typing.Optional[Gender] = None
+    drivers_license: typing.Optional[DriversLicense] = None
 
     @classmethod
     def model_construct(cls, _fields_set: set[str] | None = None, **values: typing.Any) -> typing.Self:
@@ -171,6 +182,7 @@ def model_construct(cls, _fields_set: set[str] | None = None, **values: typing.A
         obj.address = [Address.model_construct(**a) for a in values.get("address", [])]
         obj.name = [Name.model_construct(**n) for n in values.get("name", [])]
         obj.telecom = [Telecom.model_construct(**t) for t in values.get("telecom", [])]
+        obj.drivers_license = DriversLicense.model_construct(**values.get("drivers_license", {}))
         return obj
 
     @pydantic.field_validator("external_id", mode="before")
@@ -263,7 +275,8 @@ def parse_gender(cls, value):
                     return Gender.NON_BINARY
                 elif "declined" in val or "asked" in val:
                     return Gender.ASKED_DECLINED
-                return Gender.UNKNOWN
+                return Gender.UNKNOWN        
+
 
     def feature_iter(self, feature: Feature) -> typing.Iterator[str]:
         """
@@ -332,6 +345,10 @@ def feature_iter(self, feature: Feature) -> typing.Iterator[str]:
             for address in self.address:
                 if address.county:
                     yield address.county
+        elif feature == Feature.DRIVERS_LICENSE:
+            if self.drivers_license:
+                if self.drivers_license.value and self.drivers_license.authority:
+                    yield f"{self.drivers_license.value}|{self.drivers_license.authority}"
 
     def blocking_keys(self, key: models.BlockingKey) -> set[str]:
         """

tests/unit/hl7/test_fhir.py

@@ -36,6 +36,28 @@ def test_fhir_record_to_pii_record():
                         "code" : "SS"
                     }]
                 },
+            },
+              {
+                "use": "official",
+                "type": {
+                    "text": "Driver's License",
+                    "coding": [
+                        {
+                        "system": "http://terminology.hl7.org/CodeSystem/v2-0203",
+                        "code": "DL",
+                        "display": "Driver's License"
+                        }
+                    ],
+                },
+                    "system": "urn:oid:2.16.840.1.113883.3.19.3.1.8",
+                    "value": "D1234567",
+                    "assigner": {
+                    "display": "State DMV",
+                    "identifier": {
+                        "system": "urn:oid:2.16.840.1.113883.19.3.1.1", 
+                        "value": "CA"
+                    }
+                }
             }
         ],
         "name": [
@@ -117,7 +139,8 @@ def test_fhir_record_to_pii_record():
     assert pii_record.telecom[0].system == "phone"
     assert str(pii_record.race) == "WHITE"
     assert str(pii_record.gender) == "FEMALE"
-
+    assert pii_record.drivers_license.authority == "CA"
+    assert pii_record.drivers_license.value == "D1234567"
 
 def test_add_person_resource():
     bundle = load_json_asset("patient_bundle.json")

tests/unit/schemas/test_pii.py

@@ -44,6 +44,10 @@ def test_model_construct(self):
                 },
             ],
             "telecom": [{"value": "555-123-4567"}, {"value": "555-987-6543"}],
+            "drivers_license": {
+                "authority": "VA",
+                "value": "D1234567"
+            }
         }
         record = pii.PIIRecord.model_construct(**data)
         assert record.mrn == "99"
@@ -62,6 +66,8 @@ def test_model_construct(self):
         assert record.address[1].state == "CA"
         assert record.address[1].postal_code == "98765-4321"
         assert record.address[1].county == "county2"
+        assert record.drivers_license.value == "D1234567"
+        assert record.drivers_license.authority == "VA"
 
 
     def test_parse_external_id(self):
@@ -234,6 +240,7 @@ def test_feature_iter(self):
                 pii.Telecom(value="555-123-4567"),
                 pii.Telecom(value="555-987-6543"),
             ],
+            drivers_license=pii.DriversLicense(value="D1234567", authority="VA")
         )
 
         with pytest.raises(ValueError):
@@ -254,6 +261,7 @@ def test_feature_iter(self):
         assert list(record.feature_iter(pii.Feature.TELEPHONE)) == ["555-123-4567", "555-987-6543"]
         assert list(record.feature_iter(pii.Feature.SUFFIX)) == ["suffix", "suffix2"]
         assert list(record.feature_iter(pii.Feature.COUNTY)) == ["county"]
+        assert list(record.feature_iter(pii.Feature.DRIVERS_LICENSE)) == ["D1234567|VA"]
 
     def test_blocking_keys_invalid(self):
         rec = pii.PIIRecord()