Merge ~cgrabowski/maas:fix_dns_restart_when_adding_vault into maas:master

[Christian Grabowski]

always set serial if using nsupdate

[MAAS Lander (maas-lander)]

UNIT TESTS
-b fix_dns_restart_when_adding_vault lp:~cgrabowski/maas/+git/maas into -b master lp:~maas-committers/maas

STATUS: FAILED
LOG: http://maas-ci.internal:8080/job/maas-tester/1521/consoleText
COMMIT: d06b811558580b2e2c016525d39014570f22bc5e

review: Needs Fixing

[MAAS Lander (maas-lander)]

UNIT TESTS
-b fix_dns_restart_when_adding_vault lp:~cgrabowski/maas/+git/maas into -b master lp:~maas-committers/maas

STATUS: FAILED
LOG: http://maas-ci.internal:8080/job/maas-tester/1523/consoleText
COMMIT: dc58d19f9656cc61b7d4cd3328e52971b2c2bd77

review: Needs Fixing

[MAAS Lander (maas-lander)]

UNIT TESTS
-b fix_dns_restart_when_adding_vault lp:~cgrabowski/maas/+git/maas into -b master lp:~maas-committers/maas

STATUS: SUCCESS
COMMIT: f04821d7b35b75889c032ef401f9929f938de080

review: Approve

[Alexsander de Souza (alexsander-souza)]

+1

review: Approve

diff --git a/src/provisioningserver/dns/tests/test_zoneconfig.py b/src/provisioningserver/dns/tests/test_zoneconfig.py
index f97adfd..948d219 100644
--- a/src/provisioningserver/dns/tests/test_zoneconfig.py
+++ b/src/provisioningserver/dns/tests/test_zoneconfig.py
@@ -415,6 +415,56 @@ class TestDNSForwardZoneConfig(MAASTestCase):
             stdin=expected_stdin.encode("ascii"),
         )
 
+    def test_dynamic_update_sets_serial_when_no_other_updates_are_present(
+        self,
+    ):
+        patch_zone_file_config_path(self)
+        domain = factory.make_string()
+        network = factory.make_ipv4_network()
+        ipv4_hostname = factory.make_name("host")
+        ipv4_ip = factory.pick_ip_in_network(network)
+        ipv6_hostname = factory.make_name("host")
+        ipv6_ip = factory.make_ipv6_address()
+        ipv6_network = factory.make_ipv6_network()
+        dynamic_range = IPRange(ipv6_network.first, ipv6_network.last)
+        ttl = random.randint(10, 300)
+        mapping = {
+            ipv4_hostname: HostnameIPMapping(None, ttl, {ipv4_ip}),
+            ipv6_hostname: HostnameIPMapping(None, ttl, {ipv6_ip}),
+        }
+        dns_zone_config = DNSForwardZoneConfig(
+            domain,
+            serial=random.randint(1, 100),
+            mapping=mapping,
+            default_ttl=ttl,
+            dynamic_ranges=[dynamic_range],
+        )
+        self.patch(dns_zone_config, "get_GENERATE_directives")
+        run_command = self.patch(actions, "run_command")
+        dns_zone_config.write_config()
+        new_dns_zone_config = DNSForwardZoneConfig(
+            domain,
+            serial=random.randint(1, 100),
+            mapping=mapping,
+            default_ttl=ttl,
+            dynamic_ranges=[dynamic_range],
+        )
+        new_dns_zone_config.write_config()
+        expected_stdin = "\n".join(
+            [
+                "server localhost",
+                f"zone {domain}",
+                f"update add {domain} {new_dns_zone_config.default_ttl} SOA {domain}. nobody.example.com. {new_dns_zone_config.serial} 600 1800 604800 {new_dns_zone_config.default_ttl}",
+                "send\n",
+            ]
+        )
+        run_command.assert_called_once_with(
+            "nsupdate",
+            "-k",
+            get_nsupdate_key_path(),
+            stdin=expected_stdin.encode("ascii"),
+        )
+
 
 class TestDNSReverseZoneConfig(MAASTestCase):
     """Tests for DNSReverseZoneConfig."""
@@ -888,6 +938,35 @@ class TestDNSReverseZoneConfig(MAASTestCase):
             stdin=expected_stdin.encode("ascii"),
         )
 
+    def test_dynamic_update_sets_serial_when_no_other_updates_are_present(
+        self,
+    ):
+        patch_zone_file_config_path(self)
+        domain = factory.make_string()
+        network = IPNetwork("10.0.0.0/24")
+        zone = DNSReverseZoneConfig(
+            domain,
+            serial=random.randint(1, 100),
+            network=network,
+        )
+        run_command = self.patch(actions, "run_command")
+        zone.write_config()
+        zone.write_config()
+        expected_stdin = "\n".join(
+            [
+                "server localhost",
+                "zone 0.0.10.in-addr.arpa",
+                f"update add 0.0.10.in-addr.arpa {zone.default_ttl} SOA 0.0.10.in-addr.arpa. nobody.example.com. {zone.serial} 600 1800 604800 {zone.default_ttl}",
+                "send\n",
+            ]
+        )
+        run_command.assert_called_once_with(
+            "nsupdate",
+            "-k",
+            get_nsupdate_key_path(),
+            stdin=expected_stdin.encode("ascii"),
+        )
+
 
 class TestDNSReverseZoneConfig_GetGenerateDirectives(MAASTestCase):
     """Tests for `DNSReverseZoneConfig.get_GENERATE_directives()`."""
diff --git a/src/provisioningserver/dns/zoneconfig.py b/src/provisioningserver/dns/zoneconfig.py
index eb28986..13dca69 100644
--- a/src/provisioningserver/dns/zoneconfig.py
+++ b/src/provisioningserver/dns/zoneconfig.py
@@ -321,8 +321,7 @@ class DNSForwardZoneConfig(DomainConfigBase):
                 )
             )
             if not self.force_config_write and self.zone_file_exists(zi):
-                if len(self._dynamic_updates) > 0:
-                    self.dynamic_update(zi)
+                self.dynamic_update(zi)
             else:
                 self.requires_reload = True
                 self.write_zone_file(
@@ -611,8 +610,7 @@ class DNSReverseZoneConfig(DomainConfigBase):
                 )
             )
             if not self.force_config_write and self.zone_file_exists(zi):
-                if len(self._dynamic_updates) > 0:
-                    self.dynamic_update(zi)
+                self.dynamic_update(zi)
             else:
                 self.requires_reload = True
                 self.write_zone_file(