fix: Prefix names starting with numbers with an underscore in slugify function (#359)

Author: Defiantearth

changes/319.fixed

@@ -0,0 +1 @@
+Fixed an incompatibility when slugifying capirca names that start with a number by prefixing the name with an underscore.

nautobot_firewall_models/tests/test_capirca.py

@@ -2,17 +2,22 @@
 
 # ruff: noqa: F403, F405
 # pylint: disable=protected-access
-from unittest import skip
+import unittest
 from unittest.mock import patch
 
 from django.core.exceptions import ValidationError
-from django.test import TestCase
+from nautobot.apps.testing import TestCase
 from nautobot.dcim.models import Device, Platform
 from nautobot.extras.models import Status
 from nautobot.ipam.models import IPAddress, Namespace
 
 from nautobot_firewall_models.models import *  # pylint: disable=unused-wildcard-import, wildcard-import
-from nautobot_firewall_models.utils.capirca import DevicePolicyToCapirca, PolicyToCapirca, generate_capirca_config
+from nautobot_firewall_models.utils.capirca import (
+    DevicePolicyToCapirca,
+    PolicyToCapirca,
+    _slugify,
+    generate_capirca_config,
+)
 
 from .fixtures import create_capirca_env
 
@@ -280,6 +285,39 @@ def test_generate_capirca_config(self):
         self.assertEqual(actual_cfg, CFG)
 
 
+class TestSlugify(unittest.TestCase):
+    """Test models."""
+
+    def test_slugify_removes_accents(self):
+        self.assertEqual(_slugify("Café"), "Cafe")
+        self.assertEqual(_slugify("mañana"), "manana")
+
+    def test_slugify_removes_non_alphanumeric_characters(self):
+        self.assertEqual(_slugify("Hello!! World??"), "Hello-World")
+        self.assertEqual(_slugify("A*B&C(D)"), "ABCD")
+
+    def test_slugify_adds_leading_underscore_if_starts_with_digit(self):
+        self.assertEqual(_slugify("123abc"), "_123abc")
+        self.assertEqual(_slugify("9-lives"), "_9-lives")
+
+    def test_slugify_collapses_spaces_and_hyphens(self):
+        self.assertEqual(_slugify("hello   world"), "hello-world")
+        self.assertEqual(_slugify("hello---world"), "hello-world")
+        self.assertEqual(_slugify("hello_ -  world"), "hello_-world")
+
+    def test_slugify_removes_unicode_symbols(self):
+        self.assertEqual(_slugify("★Test☆string★"), "Teststring")
+
+    def test_value_is_integer(self):
+        self.assertEqual(_slugify(1234), "_1234")
+
+    def test_clean_slug(self):
+        self.assertEqual(_slugify("Clean-Slug_123"), "Clean-Slug_123")
+
+    def test_empty_string(self):
+        self.assertEqual(_slugify(""), "")
+
+
 class TestPolicyToCapirca(TestCase):  # pylint: disable=too-many-public-methods,too-many-instance-attributes
     """Test models."""
 
@@ -631,7 +669,7 @@ def setUp(self) -> None:
         create_capirca_env()
         self.device_obj = Device.objects.get(name="DFW02-WAN00")
 
-    @skip("Not implemented until policy method provided to merge queries provided")
+    @unittest.skip("Not implemented until policy method provided to merge queries provided")
     def test_dynamic_group_and_device(self):
         """Test that dynamic groups are created and device is added to it, disabled."""
 

nautobot_firewall_models/utils/capirca.py

@@ -33,11 +33,17 @@ def _slugify(value):
     dashes to single dashes. Remove characters that aren't alphanumerics,
     underscores, or hyphens. Convert to lowercase. Also strip leading and
     trailing whitespace, dashes, and underscores.
+    Also adds a leading underscore to names starting with an number to circumvent a bug in the Capirca/Aerleon parser.
     """
     value = str(value)
     value = unicodedata.normalize("NFKD", value).encode("ascii", "ignore").decode("ascii")
     value = re.sub(r"[^\w\s-]", "", value)
-    return re.sub(r"[-\s]+", "-", value).strip("-_")
+    value = re.sub(r"[-\s]+", "-", value).strip("-_")
+
+    if value[:1].isnumeric():
+        value = "_" + value
+
+    return value
 
 
 def _list_slugify(values):