Add support for enabling hotplug on interfaces

This patch adds support for enabling hotplugging on interfaces (disabled
by default). This is useful for configuring SR-IOV root devices so that
they "return" to the system when no longer used by a VM.

Note: also updates an invalid value in the interface and ib_interface
sample files.

Partial-Bug: #1639901
Change-Id: Idfc17d6f20bb306271838895bc53f4b109dd664d

etc/os-net-config/samples/ib_interface.json

@@ -20,7 +20,7 @@
       "type": "ib_interface",
       "name": "ib1",
       "use_dhcp": true,
-      "defroute": no
+      "defroute": false
     }
   ]
 }

etc/os-net-config/samples/ib_interface.yaml

@@ -15,4 +15,4 @@ network_config:
     type: interface
     name: ib1
     use_dhcp: true
-    defroute: no
+    defroute: false

etc/os-net-config/samples/interface.json

@@ -25,8 +25,14 @@
       "type": "interface",
       "name": "em2",
       "use_dhcp": true,
-      "defroute": no,
+      "defroute": false,
       "ethtool_opts": "speed 1000 duplex full"
+    },
+    {
+      "type": "interface",
+      "name": "em3",
+      "use_dhcp": true,
+      "hotplug": true
     }
   ]
 }

etc/os-net-config/samples/interface.yaml

@@ -19,5 +19,10 @@ network_config:
     type: interface
     name: em2
     use_dhcp: true
-    defroute: no
+    defroute: false
     ethtool_opts: "speed 1000 duplex full"
+  -
+    type: interface
+    name: em3
+    use_dhcp: true
+    hotplug: true

os_net_config/impl_eni.py

@@ -127,7 +127,10 @@ class ENINetConfig(os_net_config.NetConfig):
             data += address_data
             data += "    vlan-raw-device %s\n" % interface.device
         else:
-            data += "auto %s\n" % interface.name
+            if isinstance(interface, objects.Interface) and interface.hotplug:
+                data += "allow-hotplug %s\n" % interface.name
+            else:
+                data += "auto %s\n" % interface.name
             data += _iface
             data += address_data
         if interface.mtu:

os_net_config/impl_ifcfg.py

@@ -131,7 +131,10 @@ class IfcfgNetConfig(os_net_config.NetConfig):
         data = "# This file is autogenerated by os-net-config\n"
         data += "DEVICE=%s\n" % base_opt.name
         data += "ONBOOT=yes\n"
-        data += "HOTPLUG=no\n"
+        if isinstance(base_opt, objects.Interface) and base_opt.hotplug:
+            data += "HOTPLUG=yes\n"
+        else:
+            data += "HOTPLUG=no\n"
         data += "NM_CONTROLLED=no\n"
         if not base_opt.dns_servers and not base_opt.use_dhcp:
             data += "PEERDNS=no\n"

os_net_config/objects.py

@@ -287,7 +287,7 @@ class Interface(_BaseOpts):
     def __init__(self, name, use_dhcp=False, use_dhcpv6=False, addresses=None,
                  routes=None, mtu=None, primary=False, nic_mapping=None,
                  persist_mapping=False, defroute=True, dhclient_args=None,
-                 dns_servers=None, ethtool_opts=None):
+                 dns_servers=None, ethtool_opts=None, hotplug=False):
         addresses = addresses or []
         routes = routes or []
         dns_servers = dns_servers or []
@@ -296,13 +296,16 @@ class Interface(_BaseOpts):
                                         persist_mapping, defroute,
                                         dhclient_args, dns_servers)
         self.ethtool_opts = ethtool_opts
+        self.hotplug = hotplug
 
     @staticmethod
     def from_json(json):
         name = _get_required_field(json, 'name', 'Interface')
+        hotplug = strutils.bool_from_string(str(json.get('hotplug', False)))
         opts = _BaseOpts.base_opts_from_json(json)
         ethtool_opts = json.get('ethtool_opts', None)
-        return Interface(name, *opts, ethtool_opts=ethtool_opts)
+        return Interface(name, *opts, ethtool_opts=ethtool_opts,
+                         hotplug=hotplug)
 
 
 class Vlan(_BaseOpts):

os_net_config/tests/test_impl_eni.py

@@ -32,6 +32,12 @@ _V4_IFACE_STATIC_IP = _AUTO + """iface eth0 inet static
     netmask 255.255.255.0
 """
 
+_IFACE_HOTPLUG = """allow-hotplug eth0
+iface eth0 inet static
+    address 192.168.1.2
+    netmask 255.255.255.0
+"""
+
 _V4_IFACE_STATIC_IP_MULTIPLE = (_V4_IFACE_STATIC_IP + _AUTO +
                                 """iface eth0 inet static
     address 10.0.0.2
@@ -117,8 +123,9 @@ class TestENINetConfig(base.TestCase):
     def get_route_config(self):
         return self.provider.routes[self.if_name]
 
-    def _default_interface(self, addr=[], rts=[]):
-        return objects.Interface(self.if_name, addresses=addr, routes=rts)
+    def _default_interface(self, addr=[], rts=[], hotplug=False):
+        return objects.Interface(self.if_name, addresses=addr, routes=rts,
+                                 hotplug=hotplug)
 
     def test_interface_no_ip(self):
         interface = self._default_interface()
@@ -131,6 +138,12 @@ class TestENINetConfig(base.TestCase):
         self.provider.add_interface(interface)
         self.assertEqual(_V4_IFACE_STATIC_IP, self.get_interface_config())
 
+    def test_add_interface_with_hotplug(self):
+        v4_addr = objects.Address('192.168.1.2/24')
+        interface = self._default_interface(addr=[v4_addr], hotplug=True)
+        self.provider.add_interface(interface)
+        self.assertEqual(_IFACE_HOTPLUG, self.get_interface_config())
+
     def test_add_interface_with_v4_multiple(self):
         v4_addresses = [objects.Address('192.168.1.2/24'),
                         objects.Address('10.0.0.2/8')]

os_net_config/tests/test_impl_ifcfg.py

@@ -33,6 +33,15 @@ NM_CONTROLLED=no
 PEERDNS=no
 """
 
+_HOTPLUG = """# This file is autogenerated by os-net-config
+DEVICE=em1
+ONBOOT=yes
+HOTPLUG=yes
+NM_CONTROLLED=no
+PEERDNS=no
+BOOTPROTO=none
+"""
+
 _NO_IP = _BASE_IFCFG + "BOOTPROTO=none\n"
 
 _V4_IFCFG = _BASE_IFCFG + """BOOTPROTO=static
@@ -386,6 +395,11 @@ class TestIfcfgNetConfig(base.TestCase):
         self.provider.add_interface(interface)
         self.assertEqual(_NO_IP, self.get_interface_config())
 
+    def test_add_interface_with_hotplug(self):
+        interface = objects.Interface('em1', hotplug=True)
+        self.provider.add_interface(interface)
+        self.assertEqual(_HOTPLUG, self.get_interface_config())
+
     def test_add_base_interface_vlan(self):
         interface = objects.Interface('em1.120')
         self.provider.add_interface(interface)

os_net_config/tests/test_objects.py

@@ -98,6 +98,27 @@ class TestInterface(base.TestCase):
         self.assertEqual("em1", interface.name)
         self.assertTrue(interface.use_dhcp)
 
+    def test_from_json_hotplug(self):
+        data = """{
+"type": "interface",
+"name": "em1",
+"hotplug": true
+}
+"""
+        interface = objects.object_from_json(json.loads(data))
+        self.assertEqual("em1", interface.name)
+        self.assertTrue(interface.hotplug)
+
+    def test_from_json_hotplug_off_by_default(self):
+        data = """{
+"type": "interface",
+"name": "em1"
+}
+"""
+        interface = objects.object_from_json(json.loads(data))
+        self.assertEqual("em1", interface.name)
+        self.assertFalse(interface.hotplug)
+
     def test_from_json_defroute(self):
         data = '{"type": "interface", "name": "em1", "use_dhcp": true}'
         interface1 = objects.object_from_json(json.loads(data))