Add new network activators to bring up interfaces (#919)

Currently _bring_up_interfaces() is a no-op for any distro using
renderers. We need to be able to support bringing up a single
interfaces, a list of interfaces, and all interfaces. This should be
independent of the renderers, as the network config is often
generated independent of the mechanism used to apply it.

Additionally, I included a refactor to remove
"_supported_write_network_config". We had a confusing call chain of
apply_network_config->_write_network_config->_supported_write_network_config.
The last two have been combined.

1 files changed, 8 insertions, 2 deletions

diff --git a/cloudinit/net/netplan.py b/cloudinit/net/netplan.py
index 53347c83..41acf963 100644
--- a/cloudinit/net/netplan.py
+++ b/cloudinit/net/netplan.py
@@ -4,7 +4,12 @@ import copy
 import os
 
 from . import renderer
-from .network_state import subnet_is_ipv6, NET_CONFIG_TO_V2, IPV6_DYNAMIC_TYPES
+from .network_state import (
+    NetworkState,
+    subnet_is_ipv6,
+    NET_CONFIG_TO_V2,
+    IPV6_DYNAMIC_TYPES,
+)
 
 from cloudinit import log as logging
 from cloudinit import util
@@ -256,7 +261,7 @@ class Renderer(renderer.Renderer):
                     os.path.islink(SYS_CLASS_NET + iface)]:
             subp.subp(cmd, capture=True)
 
-    def _render_content(self, network_state):
+    def _render_content(self, network_state: NetworkState):
 
         # if content already in netplan format, pass it back
         if network_state.version == 2:
@@ -426,4 +431,5 @@ def network_state_to_netplan(network_state, header=None):
     contents = renderer._render_content(network_state)
     return header + contents
 
+
 # vi: ts=4 expandtab