Enhancement: better monetary field with currency code (#5858)

src/documents/migrations/1045_alter_customfieldinstance_value_monetary.py

@@ -0,0 +1,19 @@
+# Generated by Django 4.2.10 on 2024-02-22 03:52
+
+from django.db import migrations
+from django.db import models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("documents", "1044_workflow_workflowaction_workflowtrigger_and_more"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="customfieldinstance",
+            name="value_monetary",
+            field=models.CharField(max_length=128, null=True),
+        ),
+    ]

src/documents/models.py

@@ -838,7 +838,7 @@ class CustomFieldInstance(models.Model):
 
     value_float = models.FloatField(null=True)
 
-    value_monetary = models.DecimalField(null=True, decimal_places=2, max_digits=12)
+    value_monetary = models.CharField(null=True, max_length=128)
 
     value_document_ids = models.JSONField(null=True)
 

src/documents/serialisers.py

@@ -12,6 +12,7 @@ from django.contrib.auth.models import User
 from django.contrib.contenttypes.models import ContentType
 from django.core.validators import DecimalValidator
 from django.core.validators import MaxLengthValidator
+from django.core.validators import RegexValidator
 from django.core.validators import integer_validator
 from django.utils import timezone
 from django.utils.crypto import get_random_string
@@ -528,9 +529,17 @@ class CustomFieldInstanceSerializer(serializers.ModelSerializer):
             elif field.data_type == CustomField.FieldDataType.INT:
                 integer_validator(data["value"])
             elif field.data_type == CustomField.FieldDataType.MONETARY:
-                DecimalValidator(max_digits=12, decimal_places=2)(
-                    Decimal(str(data["value"])),
-                )
+                try:
+                    # First try to validate as a number from legacy format
+                    DecimalValidator(max_digits=12, decimal_places=2)(
+                        Decimal(str(data["value"])),
+                    )
+                except Exception:
+                    # If that fails, try to validate as a monetary string
+                    RegexValidator(
+                        regex=r"^[A-Z][A-Z][A-Z]\d+(\.\d{2,2})$",
+                        message="Must be a two-decimal number with optional currency code e.g. GBP123.45",
+                    )(data["value"])
             elif field.data_type == CustomField.FieldDataType.STRING:
                 MaxLengthValidator(limit_value=128)(data["value"])
 

src/documents/tests/test_api_custom_fields.py

@@ -10,7 +10,7 @@ from documents.models import Document
 from documents.tests.utils import DirectoriesMixin
 
 
-class TestCustomField(DirectoriesMixin, APITestCase):
+class TestCustomFieldsAPI(DirectoriesMixin, APITestCase):
     ENDPOINT = "/api/custom_fields/"
 
     def setUp(self):
@@ -127,6 +127,10 @@ class TestCustomField(DirectoriesMixin, APITestCase):
             name="Test Custom Field Monetary",
             data_type=CustomField.FieldDataType.MONETARY,
         )
+        custom_field_monetary2 = CustomField.objects.create(
+            name="Test Custom Field Monetary 2",
+            data_type=CustomField.FieldDataType.MONETARY,
+        )
         custom_field_documentlink = CustomField.objects.create(
             name="Test Custom Field Doc Link",
             data_type=CustomField.FieldDataType.DOCUMENTLINK,
@@ -164,7 +168,11 @@ class TestCustomField(DirectoriesMixin, APITestCase):
                     },
                     {
                         "field": custom_field_monetary.id,
-                        "value": 11.10,
+                        "value": "EUR11.10",
+                    },
+                    {
+                        "field": custom_field_monetary2.id,
+                        "value": 11.10,  # Legacy format
                     },
                     {
                         "field": custom_field_documentlink.id,
@@ -188,13 +196,14 @@ class TestCustomField(DirectoriesMixin, APITestCase):
                 {"field": custom_field_boolean.id, "value": True},
                 {"field": custom_field_url.id, "value": "https://example.com"},
                 {"field": custom_field_float.id, "value": 12.3456},
-                {"field": custom_field_monetary.id, "value": 11.10},
+                {"field": custom_field_monetary.id, "value": "EUR11.10"},
+                {"field": custom_field_monetary2.id, "value": "11.1"},
                 {"field": custom_field_documentlink.id, "value": [doc2.id]},
             ],
         )
 
         doc.refresh_from_db()
-        self.assertEqual(len(doc.custom_fields.all()), 8)
+        self.assertEqual(len(doc.custom_fields.all()), 9)
 
     def test_change_custom_field_instance_value(self):
         """
@@ -458,7 +467,7 @@ class TestCustomField(DirectoriesMixin, APITestCase):
         GIVEN:
             - Document & custom field exist
         WHEN:
-            - API request to set a field value to something not a valid monetary decimal
+            - API request to set a field value to something not a valid monetary decimal (legacy) or not a new monetary format e.g. USD12.34
         THEN:
             - HTTP 400 is returned
             - No field instance is created or attached to the document
@@ -488,6 +497,54 @@ class TestCustomField(DirectoriesMixin, APITestCase):
             format="json",
         )
 
+        self.assertEqual(resp.status_code, status.HTTP_400_BAD_REQUEST)
+
+        resp = self.client.patch(
+            f"/api/documents/{doc.id}/",
+            data={
+                "custom_fields": [
+                    {
+                        "field": custom_field_money.id,
+                        # Too few places past decimal
+                        "value": "GBP12.1",
+                    },
+                ],
+            },
+            format="json",
+        )
+
+        self.assertEqual(resp.status_code, status.HTTP_400_BAD_REQUEST)
+
+        resp = self.client.patch(
+            f"/api/documents/{doc.id}/",
+            data={
+                "custom_fields": [
+                    {
+                        "field": custom_field_money.id,
+                        # Too many places past decimal
+                        "value": "GBP12.123",
+                    },
+                ],
+            },
+            format="json",
+        )
+
+        self.assertEqual(resp.status_code, status.HTTP_400_BAD_REQUEST)
+
+        resp = self.client.patch(
+            f"/api/documents/{doc.id}/",
+            data={
+                "custom_fields": [
+                    {
+                        "field": custom_field_money.id,
+                        # Not a 3-letter currency code
+                        "value": "G12.12",
+                    },
+                ],
+            },
+            format="json",
+        )
+
         self.assertEqual(resp.status_code, status.HTTP_400_BAD_REQUEST)
         self.assertEqual(CustomFieldInstance.objects.count(), 0)
         self.assertEqual(len(doc.custom_fields.all()), 0)