add DenominationValidator to validate dosage fields in Prescription model

care/facility/migrations/0394_alter_prescription_dosage_and_more.py

@@ -0,0 +1,37 @@
+# Generated by Django 4.2.7 on 2023-11-15 18:13
+
+from django.db import migrations, models
+
+import care.facility.models.prescription
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        (
+            "facility",
+            "0393_rename_diagnosis_patientconsultation_deprecated_diagnosis_and_more",
+        ),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="prescription",
+            name="dosage",
+            field=models.CharField(
+                blank=True,
+                max_length=100,
+                null=True,
+                validators=[care.facility.models.prescription.DosageValidator()],
+            ),
+        ),
+        migrations.AlterField(
+            model_name="prescription",
+            name="max_dosage",
+            field=models.CharField(
+                blank=True,
+                max_length=100,
+                null=True,
+                validators=[care.facility.models.prescription.DosageValidator()],
+            ),
+        ),
+    ]

care/facility/models/prescription.py

@@ -37,6 +37,44 @@
     return [(tag.name, tag.value) for tag in enum_class]
 
 
+class DosageValidator:
+    min_dosage = 0.0001
+    max_dosage = 5000
+    allowed_units = {"mg", "g", "ml", "drop(s)", "ampule(s)", "tsp"}
+
+    def __call__(self, value: str):
+        if not value:
+            return
+        try:
+            value, unit = value.split(" ", maxsplit=1)
+            if unit not in self.allowed_units:
+                raise ValidationError(
+                    f"Unit must be one of {', '.join(self.allowed_units)}"
+                )
+
+            value_num: int | float = float(value)
+            if value_num.is_integer():
+                value_num = int(value_num)
+            elif len(str(value_num).split(".")[1]) > 4:
+                raise ValidationError(
+                    "Dosage amount must have at most 4 decimal places"
+                )
+
+            if len(value) != len(str(value_num)):
+                raise ValidationError("Dosage amount must be a valid number")
+
+            if self.min_dosage > value_num or value_num > self.max_dosage:
+                raise ValidationError(
+                    f"Dosage amount must be between {self.min_dosage} and {self.max_dosage}"
+                )
+        except ValueError:
+            raise ValidationError("Invalid dosage")
+
+    def deconstruct(self):
+        path = "%s.%s" % (self.__class__.__module__, self.__class__.__name__)
+        return (path, [], {})
+
+
 class MedibaseMedicineType(enum.Enum):
     BRAND = "brand"
     GENERIC = "generic"
@@ -92,7 +130,9 @@
         blank=True,
         null=True,
     )
-    dosage = models.CharField(max_length=100, blank=True, null=True)
+    dosage = models.CharField(
+        max_length=100, blank=True, null=True, validators=[DosageValidator()]
+    )
 
     is_prn = models.BooleanField(default=False)
 
@@ -107,7 +147,9 @@
 
     # prn fields
     indicator = models.TextField(blank=True, null=True)
-    max_dosage = models.CharField(max_length=100, blank=True, null=True)
+    max_dosage = models.CharField(
+        max_length=100, blank=True, null=True, validators=[DosageValidator()]
+    )
     min_hours_between_doses = models.IntegerField(blank=True, null=True)
 
     notes = models.TextField(default="", blank=True)

care/facility/tests/test_medicine_administrations_api.py → care/facility/tests/test_medicine_api.py

@@ -6,6 +6,119 @@
 from care.utils.tests.test_utils import TestUtils
 
 
+class MedicinePrescriptionApiTestCase(TestUtils, APITestCase):
+    @classmethod
+    def setUpTestData(cls) -> None:
+        cls.state = cls.create_state()
+        cls.district = cls.create_district(cls.state)
+        cls.local_body = cls.create_local_body(cls.district)
+        cls.super_user = cls.create_super_user("su", cls.district)
+        cls.facility = cls.create_facility(cls.super_user, cls.district, cls.local_body)
+        cls.user = cls.create_user("staff1", cls.district, home_facility=cls.facility)
+        cls.patient = cls.create_patient(
+            cls.district, cls.facility, local_body=cls.local_body
+        )
+        cls.consultation = cls.create_consultation(cls.patient, cls.facility)
+        meds = MedibaseMedicine.objects.all().values_list("external_id", flat=True)[:2]
+        cls.medicine1 = str(meds[0])
+
+    def setUp(self) -> None:
+        super().setUp()
+
+    def prescription_data(self, **kwargs):
+        data = {
+            "medicine": self.medicine1,
+            "prescription_type": "REGULAR",
+            "dosage": "1 mg",
+            "frequency": "OD",
+            "is_prn": False,
+        }
+        return {**data, **kwargs}
+
+    def test_invalid_dosage(self):
+        data = self.prescription_data(dosage="abc")
+        res = self.client.post(
+            f"/api/v1/consultation/{self.consultation.external_id}/prescriptions/",
+            data,
+        )
+        self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
+        self.assertEqual(res.json()["dosage"][0], "Invalid dosage")
+
+    def test_dosage_out_of_range(self):
+        data = self.prescription_data(dosage="10000 mg")
+        res = self.client.post(
+            f"/api/v1/consultation/{self.consultation.external_id}/prescriptions/",
+            data,
+        )
+        self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
+        self.assertEqual(
+            res.json()["dosage"][0],
+            "Dosage amount must be between 0.0001 and 5000",
+        )
+
+        data = self.prescription_data(dosage="-1 mg")
+        res = self.client.post(
+            f"/api/v1/consultation/{self.consultation.external_id}/prescriptions/",
+            data,
+        )
+        self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
+        self.assertEqual(
+            res.json()["dosage"][0],
+            "Dosage amount must be between 0.0001 and 5000",
+        )
+
+    def test_dosage_precision(self):
+        data = self.prescription_data(dosage="0.300003 mg")
+        res = self.client.post(
+            f"/api/v1/consultation/{self.consultation.external_id}/prescriptions/",
+            data,
+        )
+        self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
+        self.assertEqual(
+            res.json()["dosage"][0],
+            "Dosage amount must have at most 4 decimal places",
+        )
+
+    def test_dosage_unit_invalid(self):
+        data = self.prescription_data(dosage="1 abc")
+        res = self.client.post(
+            f"/api/v1/consultation/{self.consultation.external_id}/prescriptions/",
+            data,
+        )
+        self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
+        self.assertTrue(res.json()["dosage"][0].startswith("Unit must be one of"))
+
+    def test_dosage_leading_zero(self):
+        data = self.prescription_data(dosage="01 mg")
+        res = self.client.post(
+            f"/api/v1/consultation/{self.consultation.external_id}/prescriptions/",
+            data,
+        )
+        self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
+        self.assertEqual(
+            res.json()["dosage"][0], "Dosage amount must be a valid number"
+        )
+
+    def test_dosage_trailing_zero(self):
+        data = self.prescription_data(dosage="1.0 mg")
+        res = self.client.post(
+            f"/api/v1/consultation/{self.consultation.external_id}/prescriptions/",
+            data,
+        )
+        self.assertEqual(res.status_code, status.HTTP_400_BAD_REQUEST)
+        self.assertEqual(
+            res.json()["dosage"][0], "Dosage amount must be a valid number"
+        )
+
+    def test_valid_dosage(self):
+        data = self.prescription_data(dosage="1 mg")
+        res = self.client.post(
+            f"/api/v1/consultation/{self.consultation.external_id}/prescriptions/",
+            data,
+        )
+        self.assertEqual(res.status_code, status.HTTP_201_CREATED)
+
+
 class MedicineAdministrationsApiTestCase(TestUtils, APITestCase):
     @classmethod
     def setUpTestData(cls) -> None: