Merge ~lloydwaltersj/maas:check-duplicating-internal-dns-name into maas:master

[Jack Lloyd-Walters]

disallow duplicating maas_internal_domain name when creating a new DNS

[MAAS Lander (maas-lander)]

UNIT TESTS
-b check-duplicating-internal-dns-name lp:~lloydwaltersj/maas/+git/maas into -b master lp:~maas-committers/maas

STATUS: SUCCESS
COMMIT: 941e2ef85e09aa9fb69579edfa0b72e7e84d0c75

review: Approve

[Anton Troyanov (troyanov)]

LGTM

review: Approve

diff --git a/src/maasserver/forms/settings.py b/src/maasserver/forms/settings.py
index f9887e1..ea3598e 100644
--- a/src/maasserver/forms/settings.py
+++ b/src/maasserver/forms/settings.py
@@ -33,7 +33,7 @@ from maasserver.models.config import (
     DNSSEC_VALIDATION_CHOICES,
     NETWORK_DISCOVERY_CHOICES,
 )
-from maasserver.models.domain import validate_domain_name
+from maasserver.models.domain import validate_internal_domain_name
 from maasserver.storage_layouts import STORAGE_LAYOUT_CHOICES
 from maasserver.utils.forms import compose_invalid_choice_text
 from maasserver.utils.osystems import (
@@ -263,7 +263,9 @@ def make_active_discovery_interval_field(*args, **kwargs):
 
 def make_maas_internal_domain_field(*args, **kwargs):
     """Build and return the maas_internal_domain field."""
-    return forms.CharField(validators=[validate_domain_name], **kwargs)
+    return forms.CharField(
+        validators=[validate_internal_domain_name], **kwargs
+    )
 
 
 class RemoteSyslogField(forms.CharField):
diff --git a/src/maasserver/models/domain.py b/src/maasserver/models/domain.py
index 0eb538f..f3c1d71 100644
--- a/src/maasserver/models/domain.py
+++ b/src/maasserver/models/domain.py
@@ -38,6 +38,17 @@ def validate_domain_name(value):
     namespec = re.compile("^%s$" % NAMESPEC)
     if not namespec.search(value) or len(value) > 255:
         raise ValidationError("Invalid domain name: %s." % value)
+    if value == Config.objects.get_config("maas_internal_domain"):
+        raise ValidationError(
+            "Domain name cannot duplicate maas internal domain name"
+        )
+
+
+def validate_internal_domain_name(value):
+    """Django validator: `value` must be a valid DNS Zone name."""
+    namespec = re.compile("^%s$" % NAMESPEC)
+    if not namespec.search(value) or len(value) > 255:
+        raise ValidationError("Invalid domain name: %s." % value)
 
 
 NAME_VALIDATOR = RegexValidator("^%s$" % NAMESPEC)
diff --git a/src/maasserver/models/tests/test_domain.py b/src/maasserver/models/tests/test_domain.py
index dd430b0..0fdd131 100644
--- a/src/maasserver/models/tests/test_domain.py
+++ b/src/maasserver/models/tests/test_domain.py
@@ -170,6 +170,19 @@ class TestDomain(MAASServerTestCase):
             ValidationError, factory.make_Domain, name="invalid*name"
         )
 
+    def test_duplicating_internal_name_raises_exception(self):
+        internal_domain = Config.objects.get_config("maas_internal_domain")
+        self.assertRaises(
+            ValidationError, factory.make_Domain, name=internal_domain
+        )
+
+    def test_setting_internal_name_allows_old_internal_domain_name(self):
+        internal_domain_old = Config.objects.get_config("maas_internal_domain")
+        internal_domain_new = factory.make_name("internal")
+        Config.objects.set_config("maas_internal_domain", internal_domain_new)
+        domain = factory.make_Domain(name=internal_domain_old)
+        self.assertEqual(internal_domain_old, domain.name)
+
     def test_get_default_domain_is_idempotent(self):
         default_domain = Domain.objects.get_default_domain()
         default_domain2 = Domain.objects.get_default_domain()