Merge lp:~danilo/maas/bug-1699479-dhcp-test-stability into lp:~maas-committers/maas/trunk

[Данило Шеган]

Make TestDHCPNetworkLayout.test__dhcp_configurations_rendered always run in both IPv4 and IPv6 network configurations to ensure it stably either passes or fails.

To avoid resolve_hostname() on the MAAS configured URL only return an IP address that it resolves to on the local system (which could be only IPv4 or only IPv6 address) which can't be used for a DNS server, we patch resolve_hostname() in the test to return the appropriate localhost address.

This is a fix for a test that fails on LXD containers occasionally (when subnet ends up being an IPv6 network).

[Mike Pontillo (mpontillo)]

I much prefer the v4 and v6 scenario approach to pure randomness. Thanks for the fix.

review: Approve

=== modified file 'src/maasserver/testing/factory.py'
--- src/maasserver/testing/factory.py	2017-04-26 23:46:21 +0000
+++ src/maasserver/testing/factory.py	2017-06-21 12:05:32 +0000
@@ -767,6 +767,10 @@
         if 'iftype' in kwargs:
             iftype = kwargs['iftype']
             del kwargs['iftype']
+        if 'ip_version' in kwargs and cidr is None:
+            ip_version = kwargs.pop('ip_version')
+        else:
+            ip_version = None
         node = self.make_Node(fabric=fabric, **kwargs)
         if vlan is None and subnet is not None:
             vlan = subnet.vlan
@@ -778,7 +782,7 @@
             vlan.dhcp_on = dhcp_on
             vlan.save()
         if subnet is None:
-            subnet = self.make_Subnet(vlan=vlan, cidr=cidr)
+            subnet = self.make_Subnet(vlan=vlan, cidr=cidr, version=ip_version)
         boot_interface = self.make_Interface(
             iftype, name=ifname, node=node, vlan=vlan,
             mac_address=mac_address)

=== modified file 'src/maasserver/tests/test_preseed_network.py'
--- src/maasserver/tests/test_preseed_network.py	2017-03-09 16:32:52 +0000
+++ src/maasserver/tests/test_preseed_network.py	2017-06-21 12:05:32 +0000
@@ -20,9 +20,13 @@
     compose_curtin_network_config,
     NodeNetworkConfiguration,
 )
+import maasserver.server_address
 from maasserver.testing.factory import factory
 from maasserver.testing.testcase import MAASServerTestCase
-from netaddr import IPNetwork
+from netaddr import (
+    IPAddress,
+    IPNetwork,
+)
 from testtools.matchers import (
     ContainsDict,
     Equals,
@@ -406,8 +410,14 @@
 class TestDHCPNetworkLayout(MAASServerTestCase,
                             AssertNetworkConfigMixin):
 
+    scenarios = (
+        ('ipv4', {'ip_version': 4}),
+        ('ipv6', {'ip_version': 6}),
+    )
+
     def test__dhcp_configurations_rendered(self):
-        node = factory.make_Node_with_Interface_on_Subnet()
+        node = factory.make_Node_with_Interface_on_Subnet(
+            ip_version=self.ip_version)
         iface = node.interface_set.first()
         subnet = iface.vlan.subnet_set.first()
         factory.make_StaticIPAddress(
@@ -415,6 +425,14 @@
             alloc_type=IPADDRESS_TYPE.DHCP,
             interface=iface,
             subnet=subnet)
+        # Patch resolve_hostname() to return the appropriate network version
+        # IP address for MAAS hostname.
+        resolve_hostname = self.patch(
+            maasserver.server_address, "resolve_hostname")
+        if self.ip_version == 4:
+            resolve_hostname.return_value = {IPAddress("127.0.0.1")}
+        else:
+            resolve_hostname.return_value = {IPAddress("::1")}
         config = compose_curtin_network_config(node)
         config_yaml = yaml.safe_load(config[0])
         self.assertThat(