Use generated field for monetary amount to allow arithmetic filtering

src-ui/src/app/data/custom-field-query.ts

@@ -93,6 +93,7 @@ export const CUSTOM_FIELD_QUERY_OPERATOR_GROUPS_BY_TYPE = {
   [CustomFieldDataType.Monetary]: [
     CustomFieldQueryOperatorGroups.Basic,
     CustomFieldQueryOperatorGroups.String,
+    CustomFieldQueryOperatorGroups.Arithmetic,
   ],
   [CustomFieldDataType.DocumentLink]: [
     CustomFieldQueryOperatorGroups.Basic,

src/documents/filters.py

@@ -261,7 +261,7 @@ class CustomFieldQueryParser:
         CustomField.FieldDataType.BOOL: ("basic",),
         CustomField.FieldDataType.INT: ("basic", "arithmetic"),
         CustomField.FieldDataType.FLOAT: ("basic", "arithmetic"),
-        CustomField.FieldDataType.MONETARY: ("basic", "string"),
+        CustomField.FieldDataType.MONETARY: ("basic", "string", "arithmetic"),
         CustomField.FieldDataType.DOCUMENTLINK: ("basic", "containment"),
         CustomField.FieldDataType.SELECT: ("basic",),
     }
@@ -417,6 +417,13 @@ class CustomFieldQueryParser:
         value_field_name = CustomFieldInstance.get_value_field_name(
             custom_field.data_type,
         )
+        if custom_field.data_type == CustomField.FieldDataType.MONETARY and op in (
+            "gt",
+            "gte",
+            "lt",
+            "lte",
+        ):
+            value_field_name = "value_monetary_amount"
         has_field = Q(custom_fields__field=custom_field)
 
         # Our special exists operator.

src/documents/migrations/1054_customfieldinstance_value_monetary_amount_and_more.py

@@ -1,5 +1,6 @@
-# Generated by Django 5.1.1 on 2024-09-28 04:48
+# Generated by Django 5.1.1 on 2024-09-29 00:39
 
+import django.db.models.functions.text
 from django.db import migrations
 from django.db import models
 
@@ -10,6 +11,15 @@ class Migration(migrations.Migration):
     ]
 
     operations = [
+        migrations.AddField(
+            model_name="customfieldinstance",
+            name="value_monetary_amount",
+            field=models.GeneratedField(
+                db_persist=True,
+                expression=django.db.models.functions.text.Substr("value_monetary", 4),
+                output_field=models.DecimalField(decimal_places=2, max_digits=125),
+            ),
+        ),
         migrations.AlterField(
             model_name="savedviewfilterrule",
             name="rule_type",

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.functions import Substr
 from django_softdelete.models import SoftDeleteModel
 
 from documents.data_models import DocumentSource
@@ -922,6 +923,12 @@ class CustomFieldInstance(models.Model):
 
     value_monetary = models.CharField(null=True, max_length=128)
 
+    value_monetary_amount = models.GeneratedField(
+        expression=Substr("value_monetary", 4),
+        output_field=models.DecimalField(decimal_places=2, max_digits=125),
+        db_persist=True,
+    )
+
     value_document_ids = models.JSONField(null=True)
 
     value_select = models.PositiveSmallIntegerField(null=True)

src/documents/tests/test_api_filter_by_custom_fields.py

@@ -393,6 +393,14 @@ class TestCustomFieldsSearch(DirectoriesMixin, APITestCase):
             and document["date_field"].year >= 2024,
         )
 
+    def test_gt_monetary(self):
+        self._assert_query_match_predicate(
+            ["monetary_field", "gt", "99"],
+            lambda document: "monetary_field" in document
+            and document["monetary_field"] is not None
+            and document["monetary_field"] == "USD100.00",
+        )
+
     # ==========================================================#
     # Subset check (document link field only)                   #
     # ==========================================================#