support network rendering to sysconfig (for centos and RHEL)

This intends to add support for rendering of network data under sysconfig
distributions (centos and rhel).  The end result will be support for
network configuration via ConfigDrive or NoCloud on these OS.

1 files changed, 30 insertions, 39 deletions

diff --git a/cloudinit/net/eni.py b/cloudinit/net/eni.py
index 5a90eb32..ccd16ba7 100644
--- a/cloudinit/net/eni.py
+++ b/cloudinit/net/eni.py
@@ -16,10 +16,9 @@ import glob
 import os
 import re
 
-from . import LINKS_FNAME_PREFIX
 from . import ParserError
 
-from .udev import generate_udev_rule
+from . import renderer
 
 from cloudinit import util
 
@@ -297,21 +296,17 @@ def _ifaces_to_net_config_data(ifaces):
             'config': [devs[d] for d in sorted(devs)]}
 
 
-class Renderer(object):
+class Renderer(renderer.Renderer):
     """Renders network information in a /etc/network/interfaces format."""
 
-    def _render_persistent_net(self, network_state):
-        """Given state, emit udev rules to map mac to ifname."""
-        content = ""
-        interfaces = network_state.get('interfaces')
-        for iface in interfaces.values():
-            # for physical interfaces write out a persist net udev rule
-            if iface['type'] == 'physical' and \
-               'name' in iface and iface.get('mac_address'):
-                content += generate_udev_rule(iface['name'],
-                                              iface['mac_address'])
-
-        return content
+    def __init__(self, config=None):
+        if not config:
+            config = {}
+        self.eni_path = config.get('eni_path', 'etc/network/interfaces')
+        self.links_path_prefix = config.get(
+            'links_path_prefix', 'etc/systemd/network/50-cloud-init-')
+        self.netrules_path = config.get(
+            'netrules_path', 'etc/udev/rules.d/70-persistent-net.rules')
 
     def _render_route(self, route, indent=""):
         """When rendering routes for an iface, in some cases applying a route
@@ -360,7 +355,15 @@ class Renderer(object):
         '''Given state, emit etc/network/interfaces content.'''
 
         content = ""
-        interfaces = network_state.get('interfaces')
+        content += "auto lo\niface lo inet loopback\n"
+
+        nameservers = network_state.dns_nameservers
+        if nameservers:
+            content += "    dns-nameservers %s\n" % (" ".join(nameservers))
+        searchdomains = network_state.dns_searchdomains
+        if searchdomains:
+            content += "    dns-search %s\n" % (" ".join(searchdomains))
+
         ''' Apply a sort order to ensure that we write out
             the physical interfaces first; this is critical for
             bonding
@@ -371,12 +374,7 @@ class Renderer(object):
             'bridge': 2,
             'vlan': 3,
         }
-        content += "auto lo\niface lo inet loopback\n"
-        for dnskey, value in network_state.get('dns', {}).items():
-            if len(value):
-                content += "    dns-{} {}\n".format(dnskey, " ".join(value))
-
-        for iface in sorted(interfaces.values(),
+        for iface in sorted(network_state.iter_interfaces(),
                             key=lambda k: (order[k['type']], k['name'])):
 
             if content[-2:] != "\n\n":
@@ -409,40 +407,33 @@ class Renderer(object):
                 content += "iface {name} {inet} {mode}\n".format(**iface)
                 content += _iface_add_attrs(iface)
 
-        for route in network_state.get('routes'):
+        for route in network_state.iter_routes():
             content += self._render_route(route)
 
         # global replacements until v2 format
         content = content.replace('mac_address', 'hwaddress')
         return content
 
-    def render_network_state(
-        self, target, network_state, eni="etc/network/interfaces",
-            links_prefix=LINKS_FNAME_PREFIX,
-            netrules='etc/udev/rules.d/70-persistent-net.rules',
-            writer=None):
-
-        fpeni = os.path.sep.join((target, eni,))
+    def render_network_state(self, target, network_state):
+        fpeni = os.path.join(target, self.eni_path)
         util.ensure_dir(os.path.dirname(fpeni))
         util.write_file(fpeni, self._render_interfaces(network_state))
 
-        if netrules:
-            netrules = os.path.sep.join((target, netrules,))
+        if self.netrules_path:
+            netrules = os.path.join(target, self.netrules_path)
             util.ensure_dir(os.path.dirname(netrules))
             util.write_file(netrules,
                             self._render_persistent_net(network_state))
 
-        if links_prefix:
+        if self.links_path_prefix:
             self._render_systemd_links(target, network_state,
-                                       links_prefix=links_prefix)
+                                       links_prefix=self.links_path_prefix)
 
-    def _render_systemd_links(self, target, network_state,
-                              links_prefix=LINKS_FNAME_PREFIX):
-        fp_prefix = os.path.sep.join((target, links_prefix))
+    def _render_systemd_links(self, target, network_state, links_prefix):
+        fp_prefix = os.path.join(target, links_prefix)
         for f in glob.glob(fp_prefix + "*"):
             os.unlink(f)
-        interfaces = network_state.get('interfaces')
-        for iface in interfaces.values():
+        for iface in network_state.iter_interfaces():
             if (iface['type'] == 'physical' and 'name' in iface and
                     iface.get('mac_address')):
                 fname = fp_prefix + iface['name'] + ".link"