Working removal of custom fields

src/documents/migrations/1040_customfield_customfieldboolean_customfielddate_and_more.py

@@ -219,6 +219,13 @@ class Migration(migrations.Migration):
                 ),
             ],
         ),
+        migrations.AddConstraint(
+            model_name="customfield",
+            constraint=models.UniqueConstraint(
+                fields=("name",),
+                name="documents_customfield_unique_name",
+            ),
+        ),
         migrations.AddConstraint(
             model_name="customfieldinstance",
             constraint=models.UniqueConstraint(

src/documents/models.py

@@ -916,6 +916,12 @@ class CustomField(models.Model):
         ordering = ("created",)
         verbose_name = _("custom field")
         verbose_name_plural = _("custom fields")
+        constraints = [
+            models.UniqueConstraint(
+                fields=["name"],
+                name="%(app_label)s_%(class)s_unique_name",
+            ),
+        ]
 
     def __str__(self) -> str:
         return f"{self.name} : {self.data_type}"

src/documents/serialisers.py

@@ -464,7 +464,7 @@ class DocumentSerializer(OwnedObjectSerializer, DynamicFieldsModelSerializer):
                 field_instance["value"] = data_custom_field["value"]
         return values
 
-    def update(self, instance, validated_data):
+    def update(self, instance: Document, validated_data):
         if "custom_fields" in validated_data:
             custom_fields = validated_data.pop("custom_fields")
             for field_data in custom_fields:
@@ -473,6 +473,19 @@ class DocumentSerializer(OwnedObjectSerializer, DynamicFieldsModelSerializer):
                     field=field_data["field"],
                     value=field_data["value"],
                 )
+            existing_fields = CustomFieldInstance.objects.filter(document=instance)
+            for existing_field in existing_fields:
+                if (
+                    not len(
+                        [
+                            f
+                            for f in custom_fields
+                            if f["field"]["id"] == existing_field.field.id
+                        ],
+                    )
+                    > 0
+                ):
+                    existing_field.delete()
         if "created_date" in validated_data and "created" not in validated_data:
             new_datetime = datetime.datetime.combine(
                 validated_data.get("created_date"),