Fix numbered NIC mapping when using dotted VLAN notation

When declaring VLANs using dotted notation (such as em1.10
for VLAN 10 on interface em1), numbered NICs are not
properly mapped to real interface names. This patch fixes
the handling of the mapped NIC names inside the BaseOpts
object that is the base class for all interface types.
This allows an interface name of "nic1.10" to be mapped
to, e.g. "em1.10"

Closes-bug: #1783206

Change-Id: Ibd9b28128900d9e959b82eb8673b8380bf20606a
(cherry picked from commit e12837353d)

os_net_config/objects.py

@@ -262,14 +262,22 @@ class _BaseOpts(object):
         self.hwaddr = None
         self.hwname = None
         self.renamed = False
-        if name in mapped_nic_names:
+        # Split name to support <nic>.<vlan_id> format, e.g. em1.10 or nic1.10
+        if len(name.split('.')) > 1 and name.split('.')[1].isdigit():
+            base_name = name.split('.')[0]
+            vlan_suffix = '.%s' % name.split('.')[1]
+        else:
+            base_name = name
+            vlan_suffix = ''
+        if base_name in mapped_nic_names:
             if persist_mapping:
                 self.name = name
-                self.hwname = mapped_nic_names[name]
+                self.hwname = '%s%s' % (mapped_nic_names[base_name],
+                                        vlan_suffix)
                 self.hwaddr = utils.interface_mac(self.hwname)
                 self.renamed = True
             else:
-                self.name = mapped_nic_names[name]
+                self.name = '%s%s' % (mapped_nic_names[base_name], vlan_suffix)
         else:
             self.name = name
 

os_net_config/tests/test_objects.py

@@ -98,6 +98,15 @@ class TestInterface(base.TestCase):
         self.assertEqual("em1", interface.name)
         self.assertTrue(interface.use_dhcp)
 
+    def test_from_json_dotted_vlan(self):
+        def dummy_mapped_nics(nic_mapping=None):
+            return {"nic1": "em3"}
+        self.stub_out('os_net_config.objects.mapped_nics', dummy_mapped_nics)
+
+        data = '{"type": "interface", "name": "nic1.10", "use_dhcp": true}'
+        interface = objects.object_from_json(json.loads(data))
+        self.assertEqual("em3.10", interface.name)
+
     def test_from_json_hotplug(self):
         data = """{
 "type": "interface",