Enforce custom field validation on the model

netbox/extras/api/customfields.py

@@ -1,8 +1,4 @@
-import re
-from datetime import datetime
-
 from django.contrib.contenttypes.models import ContentType
-from rest_framework.exceptions import ValidationError
 from rest_framework.fields import CreateOnlyDefault, Field
 
 from extras.choices import *
@@ -66,63 +62,6 @@ class CustomFieldsDataField(Field):
         if self.parent.instance:
             data = {**self.parent.instance.custom_field_data, **data}
 
-        custom_fields = {field.name: field for field in self._get_custom_fields()}
-
-        for field_name, value in data.items():
-
-            try:
-                cf = custom_fields[field_name]
-            except KeyError:
-                raise ValidationError(f"Invalid custom field name: {field_name}")
-
-            # Data validation
-            if value not in [None, '']:
-
-                # Validate text field
-                if cf.type == CustomFieldTypeChoices.TYPE_TEXT and cf.validation_regex:
-                    if not re.match(cf.validation_regex, value):
-                        raise ValidationError(f"{field_name}: Value must match regex {cf.validation_regex}")
-
-                # Validate integer
-                if cf.type == CustomFieldTypeChoices.TYPE_INTEGER:
-                    try:
-                        int(value)
-                    except ValueError:
-                        raise ValidationError(f"Invalid value for integer field {field_name}: {value}")
-                    if cf.validation_minimum is not None and value < cf.validation_minimum:
-                        raise ValidationError(f"{field_name}: Value must be at least {cf.validation_minimum}")
-                    if cf.validation_maximum is not None and value > cf.validation_maximum:
-                        raise ValidationError(f"{field_name}: Value must not exceed {cf.validation_maximum}")
-
-                # Validate boolean
-                if cf.type == CustomFieldTypeChoices.TYPE_BOOLEAN and value not in [True, False, 1, 0]:
-                    raise ValidationError(f"Invalid value for boolean field {field_name}: {value}")
-
-                # Validate date
-                if cf.type == CustomFieldTypeChoices.TYPE_DATE:
-                    try:
-                        datetime.strptime(value, '%Y-%m-%d')
-                    except ValueError:
-                        raise ValidationError(
-                            f"Invalid date for field {field_name}: {value}. (Required format is YYYY-MM-DD.)"
-                        )
-
-                # Validate selected choice
-                if cf.type == CustomFieldTypeChoices.TYPE_SELECT:
-                    if value not in cf.choices:
-                        raise ValidationError(f"Invalid choice for field {field_name}: {value}")
-
-            elif cf.required:
-                raise ValidationError(f"Required field {field_name} cannot be empty.")
-
-        # Check for missing required fields
-        missing_fields = []
-        for field_name, field in custom_fields.items():
-            if field.required and field_name not in data:
-                missing_fields.append(field_name)
-        if missing_fields:
-            raise ValidationError("Missing required fields: {}".format(u", ".join(missing_fields)))
-
         return data
 
 

netbox/extras/models/customfields.py

@@ -1,4 +1,6 @@
+import re
 from collections import OrderedDict
+from datetime import datetime
 
 from django import forms
 from django.contrib.contenttypes.models import ContentType
@@ -8,10 +10,10 @@ from django.core.validators import RegexValidator, ValidationError
 from django.db import models
 from django.utils.safestring import mark_safe
 
-from utilities.forms import CSVChoiceField, DatePicker, LaxURLField, StaticSelect2, add_blank_choice
-from utilities.validators import validate_regex
 from extras.choices import *
 from extras.utils import FeatureQuery
+from utilities.forms import CSVChoiceField, DatePicker, LaxURLField, StaticSelect2, add_blank_choice
+from utilities.validators import validate_regex
 
 
 class CustomFieldModel(models.Model):
@@ -44,14 +46,21 @@ class CustomFieldModel(models.Model):
         ])
 
     def clean(self):
+        custom_fields = {cf.name: cf for cf in CustomField.objects.get_for_model(self)}
+
+        # Validate all field values
+        for field_name, value in self.custom_field_data.items():
+            if field_name not in custom_fields:
+                raise ValidationError(f"Unknown field name '{field_name}' in custom field data.")
+            try:
+                custom_fields[field_name].validate(value)
+            except ValidationError as e:
+                raise ValidationError(f"Invalid value for custom field '{field_name}': {e.message}")
 
-        # Validate custom field data
-        custom_field_names = CustomField.objects.get_for_model(self).values_list('name', flat=True)
-        for field_name in self.custom_field_data:
-            if field_name not in custom_field_names:
-                raise ValidationError({
-                    'custom_field_data': f'Unknown custom field: {field_name}'
-                })
+        # Check for missing required values
+        for cf in custom_fields.values():
+            if cf.required and cf.name not in self.custom_field_data:
+                raise ValidationError(f"Missing required custom field '{cf.name}'.")
 
 
 class CustomFieldManager(models.Manager):
@@ -270,3 +279,46 @@ class CustomField(models.Model):
             field.help_text = self.description
 
         return field
+
+    def validate(self, value):
+        """
+        Validate a value according to the field's type validation rules.
+        """
+        if value not in [None, '']:
+
+            # Validate text field
+            if self.type == CustomFieldTypeChoices.TYPE_TEXT and self.validation_regex:
+                if not re.match(self.validation_regex, value):
+                    raise ValidationError(f"Value must match regex '{self.validation_regex}'")
+
+            # Validate integer
+            if self.type == CustomFieldTypeChoices.TYPE_INTEGER:
+                try:
+                    int(value)
+                except ValueError:
+                    raise ValidationError("Value must be an integer.")
+                if self.validation_minimum is not None and value < self.validation_minimum:
+                    raise ValidationError(f"Value must be at least {self.validation_minimum}")
+                if self.validation_maximum is not None and value > self.validation_maximum:
+                    raise ValidationError(f"Value must not exceed {self.validation_maximum}")
+
+            # Validate boolean
+            if self.type == CustomFieldTypeChoices.TYPE_BOOLEAN and value not in [True, False, 1, 0]:
+                raise ValidationError("Value must be true or false.")
+
+            # Validate date
+            if self.type == CustomFieldTypeChoices.TYPE_DATE:
+                try:
+                    datetime.strptime(value, '%Y-%m-%d')
+                except ValueError:
+                    raise ValidationError("Date values must be in the format YYYY-MM-DD.")
+
+            # Validate selected choice
+            if self.type == CustomFieldTypeChoices.TYPE_SELECT:
+                if value not in self.choices:
+                    raise ValidationError(
+                        f"Invalid choice ({value}). Available choices are: {', '.join(self.choices)}"
+                    )
+
+        elif self.required:
+            raise ValidationError("Required field cannot be empty.")

netbox/extras/tests/test_customfields.py

@@ -550,6 +550,10 @@ class CustomFieldModelTest(TestCase):
         cf2.content_types.set([ContentType.objects.get_for_model(Rack)])
 
     def test_cf_data(self):
+        """
+        Check that custom field data is present on the instance immediately after being set and after being fetched
+        from the database.
+        """
         site = Site(name='Test Site', slug='test-site')
 
         # Check custom field data on new instance
@@ -570,9 +574,26 @@ class CustomFieldModelTest(TestCase):
         # Set custom field data
         site.cf['foo'] = 'abc'
         site.cf['bar'] = 'def'
-
         with self.assertRaises(ValidationError):
             site.clean()
 
         del(site.cf['bar'])
         site.clean()
+
+    def test_missing_required_field(self):
+        """
+        Check that a ValidationError is raised if any required custom fields are not present.
+        """
+        cf3 = CustomField(type=CustomFieldTypeChoices.TYPE_TEXT, name='baz', required=True)
+        cf3.save()
+        cf3.content_types.set([ContentType.objects.get_for_model(Site)])
+
+        site = Site(name='Test Site', slug='test-site')
+
+        # Set custom field data with a required field omitted
+        site.cf['foo'] = 'abc'
+        with self.assertRaises(ValidationError):
+            site.clean()
+
+        site.cf['baz'] = 'def'
+        site.clean()