Handle cases where monetary field has no currency

src/documents/migrations/1054_customfieldinstance_value_monetary_amount_and_more.py

@@ -1,4 +1,4 @@
-# Generated by Django 5.1.1 on 2024-09-29 00:39
+# Generated by Django 5.1.1 on 2024-09-29 05:16
 
 import django.db.models.functions.text
 from django.db import migrations
@@ -16,7 +16,17 @@ class Migration(migrations.Migration):
             name="value_monetary_amount",
             field=models.GeneratedField(
                 db_persist=True,
-                expression=django.db.models.functions.text.Substr("value_monetary", 4),
+                expression=models.Case(
+                    models.When(
+                        then=django.db.models.functions.text.Substr(
+                            "value_monetary",
+                            1,
+                        ),
+                        value_monetary__regex="^\\d+",
+                    ),
+                    default=django.db.models.functions.text.Substr("value_monetary", 4),
+                    output_field=models.DecimalField(decimal_places=2, max_digits=125),
+                ),
                 output_field=models.DecimalField(decimal_places=2, max_digits=125),
             ),
         ),

src/documents/models.py

@@ -22,6 +22,7 @@ from multiselectfield import MultiSelectField
 if settings.AUDIT_LOG_ENABLED:
     from auditlog.registry import auditlog
 
+from django.db.models import Case
 from django.db.models.functions import Substr
 from django_softdelete.models import SoftDeleteModel
 
@@ -924,7 +925,16 @@ class CustomFieldInstance(models.Model):
     value_monetary = models.CharField(null=True, max_length=128)
 
     value_monetary_amount = models.GeneratedField(
-        expression=Substr("value_monetary", 4),
+        expression=Case(
+            # If the value starts with a number and no currency symbol, use the whole string
+            models.When(
+                value_monetary__regex=r"^\d+",
+                then=Substr("value_monetary", 1),
+            ),
+            # If the value starts with a 3-char currency symbol, use the rest of the string
+            default=Substr("value_monetary", 4),
+            output_field=models.DecimalField(decimal_places=2, max_digits=125),
+        ),
         output_field=models.DecimalField(decimal_places=2, max_digits=125),
         db_persist=True,
     )

src/documents/tests/test_api_filter_by_custom_fields.py

@@ -104,6 +104,7 @@ class TestCustomFieldsSearch(DirectoriesMixin, APITestCase):
         self._create_document(monetary_field="USD100.00")
         self._create_document(monetary_field="USD1.00")
         self._create_document(monetary_field="EUR50.00")
+        self._create_document(monetary_field="101.00")
 
         # CustomField.FieldDataType.DOCUMENTLINK
         self._create_document(documentlink_field=None)
@@ -398,7 +399,10 @@ class TestCustomFieldsSearch(DirectoriesMixin, APITestCase):
             ["monetary_field", "gt", "99"],
             lambda document: "monetary_field" in document
             and document["monetary_field"] is not None
-            and document["monetary_field"] == "USD100.00",
+            and (
+                document["monetary_field"] == "USD100.00"  # With currency symbol
+                or document["monetary_field"] == "101.00"  # No currency symbol
+            ),
         )
 
     # ==========================================================#