Merge lp:~harlowja/cloud-init/cloud-init-net-sysconfig into lp:~cloud-init-dev/cloud-init/trunk

[Joshua Harlow]

[lp:~harlowja/cloud-init/cloud-init-net-sysconfig]

1235. By Joshua Harlow on 2016-06-10

Add a sysconfig rendering test

1236. By Joshua Harlow on 2016-06-10

Add a bunch more sample tests for sysconfig

1237. By Joshua Harlow on 2016-06-13

Refactor some of sysconfig changes -> network_state module

1238. By Joshua Harlow on 2016-06-14

Make the os samples easier to extend (for new samples)

[Scott Moser (smoser)]

remove your print statements.
i guess go ahead and fix the TODO that you added.

running 'tox' fails for me, always good to fix that .

the rest of it looks reasonable.

[Scott Moser (smoser)]

links_prefix support would be ncie in the renderer.
for persistent naming with systemd.link
that might be shared with eni

[lp:~harlowja/cloud-init/cloud-init-net-sysconfig]

1239. By Joshua Harlow on 2016-06-15

Fixup code review comments

1240. By Joshua Harlow on 2016-06-15

Fix line length issues

[Joshua Harlow (harlowja)]

done.

=== modified file 'cloudinit/distros/debian.py'
--- cloudinit/distros/debian.py	2016-06-10 21:40:05 +0000
+++ cloudinit/distros/debian.py	2016-06-15 23:16:02 +0000
@@ -57,7 +57,11 @@
         # should only happen say once per instance...)
         self._runner = helpers.Runners(paths)
         self.osfamily = 'debian'
-        self._net_renderer = eni.Renderer()
+        self._net_renderer = eni.Renderer({
+            'eni_path': self.network_conf_fn,
+            'links_prefix_path': self.links_prefix,
+            'netrules_path': None,
+        })
 
     def apply_locale(self, locale, out_fn=None):
         if not out_fn:
@@ -81,13 +85,17 @@
         return ['all']
 
     def _write_network_config(self, netconfig):
+<<<<<<< TREE
         ns = parse_net_config_data(netconfig)
         self._net_renderer.render_network_state(
             target="/", network_state=ns,
             eni=self.network_conf_fn, links_prefix=self.links_prefix,
             netrules=None)
+=======
+        ns = net.parse_net_config_data(netconfig)
+        self._net_renderer.render_network_state("/", ns)
+>>>>>>> MERGE-SOURCE
         _maybe_remove_legacy_eth0()
-
         return []
 
     def _bring_up_interfaces(self, device_names):

=== modified file 'cloudinit/distros/rhel.py'
--- cloudinit/distros/rhel.py	2015-06-02 20:27:57 +0000
+++ cloudinit/distros/rhel.py	2016-06-15 23:16:02 +0000
@@ -23,6 +23,8 @@
 from cloudinit import distros
 from cloudinit import helpers
 from cloudinit import log as logging
+from cloudinit.net.network_state import parse_net_config_data
+from cloudinit.net import sysconfig
 from cloudinit import util
 
 from cloudinit.distros import net_util
@@ -59,10 +61,16 @@
         # should only happen say once per instance...)
         self._runner = helpers.Runners(paths)
         self.osfamily = 'redhat'
+        self._net_renderer = sysconfig.Renderer()
 
     def install_packages(self, pkglist):
         self.package_command('install', pkgs=pkglist)
 
+    def _write_network_config(self, netconfig):
+        ns = parse_net_config_data(netconfig)
+        self._net_renderer.render_network_state("/", ns)
+        return []
+
     def _write_network(self, settings):
         # TODO(harlowja) fix this... since this is the ubuntu format
         entries = net_util.translate_network(settings)

=== modified file 'cloudinit/net/__init__.py'
--- cloudinit/net/__init__.py	2016-06-07 01:42:29 +0000
+++ cloudinit/net/__init__.py	2016-06-15 23:16:02 +0000
@@ -26,7 +26,6 @@
 LOG = logging.getLogger(__name__)
 SYS_CLASS_NET = "/sys/class/net/"
 DEFAULT_PRIMARY_INTERFACE = 'eth0'
-LINKS_FNAME_PREFIX = "etc/systemd/network/50-cloud-init-"
 
 
 def sys_dev_path(devname, path=""):

=== modified file 'cloudinit/net/eni.py'
--- cloudinit/net/eni.py	2016-06-14 19:18:53 +0000
+++ cloudinit/net/eni.py	2016-06-15 23:16:02 +0000
@@ -16,10 +16,9 @@
 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 @@
             '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 @@
         '''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 @@
             '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 @@
                 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"

=== modified file 'cloudinit/net/network_state.py'
--- cloudinit/net/network_state.py	2016-06-07 17:59:27 +0000
+++ cloudinit/net/network_state.py	2016-06-15 23:16:02 +0000
@@ -38,10 +38,10 @@
     """
     state = None
     if 'version' in net_config and 'config' in net_config:
-        ns = NetworkState(version=net_config.get('version'),
-                          config=net_config.get('config'))
-        ns.parse_config(skip_broken=skip_broken)
-        state = ns.network_state
+        nsi = NetworkStateInterpreter(version=net_config.get('version'),
+                                      config=net_config.get('config'))
+        nsi.parse_config(skip_broken=skip_broken)
+        state = nsi.network_state
     return state
 
 
@@ -57,11 +57,10 @@
 
 
 def from_state_file(state_file):
-    network_state = None
     state = util.read_conf(state_file)
-    network_state = NetworkState()
-    network_state.load(state)
-    return network_state
+    nsi = NetworkStateInterpreter()
+    nsi.load(state)
+    return nsi
 
 
 def diff_keys(expected, actual):
@@ -113,8 +112,50 @@
                                                       parents, dct)
 
 
+class NetworkState(object):
+
+    def __init__(self, network_state, version=NETWORK_STATE_VERSION):
+        self._network_state = copy.deepcopy(network_state)
+        self._version = version
+
+    @property
+    def version(self):
+        return self._version
+
+    def iter_routes(self, filter_func=None):
+        for route in self._network_state.get('routes', []):
+            if filter_func is not None:
+                if filter_func(route):
+                    yield route
+            else:
+                yield route
+
+    @property
+    def dns_nameservers(self):
+        try:
+            return self._network_state['dns']['nameservers']
+        except KeyError:
+            return []
+
+    @property
+    def dns_searchdomains(self):
+        try:
+            return self._network_state['dns']['search']
+        except KeyError:
+            return []
+
+    def iter_interfaces(self, filter_func=None):
+        ifaces = self._network_state.get('interfaces', {})
+        for iface in six.itervalues(ifaces):
+            if filter_func is None:
+                yield iface
+            else:
+                if filter_func(iface):
+                    yield iface
+
+
 @six.add_metaclass(CommandHandlerMeta)
-class NetworkState(object):
+class NetworkStateInterpreter(object):
 
     initial_network_state = {
         'interfaces': {},
@@ -126,22 +167,27 @@
     }
 
     def __init__(self, version=NETWORK_STATE_VERSION, config=None):
-        self.version = version
-        self.config = config
-        self.network_state = copy.deepcopy(self.initial_network_state)
+        self._version = version
+        self._config = config
+        self._network_state = copy.deepcopy(self.initial_network_state)
+        self._parsed = False
+
+    @property
+    def network_state(self):
+        return NetworkState(self._network_state, version=self._version)
 
     def dump(self):
         state = {
-            'version': self.version,
-            'config': self.config,
-            'network_state': self.network_state,
+            'version': self._version,
+            'config': self._config,
+            'network_state': self._network_state,
         }
         return util.yaml_dumps(state)
 
     def load(self, state):
         if 'version' not in state:
             LOG.error('Invalid state, missing version field')
-            raise Exception('Invalid state, missing version field')
+            raise ValueError('Invalid state, missing version field')
 
         required_keys = NETWORK_STATE_REQUIRED_KEYS[state['version']]
         missing_keys = diff_keys(required_keys, state)
@@ -155,11 +201,11 @@
             setattr(self, key, state[key])
 
     def dump_network_state(self):
-        return util.yaml_dumps(self.network_state)
+        return util.yaml_dumps(self._network_state)
 
     def parse_config(self, skip_broken=True):
         # rebuild network state
-        for command in self.config:
+        for command in self._config:
             command_type = command['type']
             try:
                 handler = self.command_handlers[command_type]
@@ -189,7 +235,7 @@
         }
         '''
 
-        interfaces = self.network_state.get('interfaces')
+        interfaces = self._network_state.get('interfaces', {})
         iface = interfaces.get(command['name'], {})
         for param, val in command.get('params', {}).items():
             iface.update({param: val})
@@ -215,7 +261,7 @@
             'gateway': None,
             'subnets': subnets,
         })
-        self.network_state['interfaces'].update({command.get('name'): iface})
+        self._network_state['interfaces'].update({command.get('name'): iface})
         self.dump_network_state()
 
     @ensure_command_keys(['name', 'vlan_id', 'vlan_link'])
@@ -228,7 +274,7 @@
                     hwaddress ether BC:76:4E:06:96:B3
                     vlan-raw-device eth0
         '''
-        interfaces = self.network_state.get('interfaces')
+        interfaces = self._network_state.get('interfaces', {})
         self.handle_physical(command)
         iface = interfaces.get(command.get('name'), {})
         iface['vlan-raw-device'] = command.get('vlan_link')
@@ -263,12 +309,12 @@
         '''
 
         self.handle_physical(command)
-        interfaces = self.network_state.get('interfaces')
+        interfaces = self._network_state.get('interfaces')
         iface = interfaces.get(command.get('name'), {})
         for param, val in command.get('params').items():
             iface.update({param: val})
         iface.update({'bond-slaves': 'none'})
-        self.network_state['interfaces'].update({iface['name']: iface})
+        self._network_state['interfaces'].update({iface['name']: iface})
 
         # handle bond slaves
         for ifname in command.get('bond_interfaces'):
@@ -280,13 +326,13 @@
                 # inject placeholder
                 self.handle_physical(cmd)
 
-            interfaces = self.network_state.get('interfaces')
+            interfaces = self._network_state.get('interfaces', {})
             bond_if = interfaces.get(ifname)
             bond_if['bond-master'] = command.get('name')
             # copy in bond config into slave
             for param, val in command.get('params').items():
                 bond_if.update({param: val})
-            self.network_state['interfaces'].update({ifname: bond_if})
+            self._network_state['interfaces'].update({ifname: bond_if})
 
     @ensure_command_keys(['name', 'bridge_interfaces', 'params'])
     def handle_bridge(self, command):
@@ -319,7 +365,7 @@
 
         # find one of the bridge port ifaces to get mac_addr
         # handle bridge_slaves
-        interfaces = self.network_state.get('interfaces')
+        interfaces = self._network_state.get('interfaces', {})
         for ifname in command.get('bridge_interfaces'):
             if ifname in interfaces:
                 continue
@@ -330,7 +376,7 @@
             # inject placeholder
             self.handle_physical(cmd)
 
-        interfaces = self.network_state.get('interfaces')
+        interfaces = self._network_state.get('interfaces', {})
         self.handle_physical(command)
         iface = interfaces.get(command.get('name'), {})
         iface['bridge_ports'] = command['bridge_interfaces']
@@ -341,7 +387,7 @@
 
     @ensure_command_keys(['address'])
     def handle_nameserver(self, command):
-        dns = self.network_state.get('dns')
+        dns = self._network_state.get('dns')
         if 'address' in command:
             addrs = command['address']
             if not type(addrs) == list:
@@ -357,7 +403,7 @@
 
     @ensure_command_keys(['destination'])
     def handle_route(self, command):
-        routes = self.network_state.get('routes')
+        routes = self._network_state.get('routes', [])
         network, cidr = command['destination'].split("/")
         netmask = cidr2mask(int(cidr))
         route = {

=== added file 'cloudinit/net/renderer.py'
--- cloudinit/net/renderer.py	1970-01-01 00:00:00 +0000
+++ cloudinit/net/renderer.py	2016-06-15 23:16:02 +0000
@@ -0,0 +1,48 @@
+#   Copyright (C) 2013-2014 Canonical Ltd.
+#
+#   Author: Scott Moser <[e-mail]>
+#   Author: Blake Rouse <[e-mail]>
+#
+#   Curtin is free software: you can redistribute it and/or modify it under
+#   the terms of the GNU Affero General Public License as published by the
+#   Free Software Foundation, either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   Curtin is distributed in the hope that it will be useful, but WITHOUT ANY
+#   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+#   FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for
+#   more details.
+#
+#   You should have received a copy of the GNU Affero General Public License
+#   along with Curtin.  If not, see <http://www.gnu.org/licenses/>.
+
+import six
+
+from .udev import generate_udev_rule
+
+
+def filter_by_type(match_type):
+    return lambda iface: match_type == iface['type']
+
+
+def filter_by_name(match_name):
+    return lambda iface: match_name == iface['name']
+
+
+filter_by_physical = filter_by_type('physical')
+
+
+class Renderer(object):
+
+    @staticmethod
+    def _render_persistent_net(network_state):
+        """Given state, emit udev rules to map mac to ifname."""
+        # TODO(harlowja): this seems shared between eni renderer and
+        # this, so move it to a shared location.
+        content = six.StringIO()
+        for iface in network_state.iter_interfaces(filter_by_physical):
+            # for physical interfaces write out a persist net udev rule
+            if 'name' in iface and iface.get('mac_address'):
+                content.write(generate_udev_rule(iface['name'],
+                                                 iface['mac_address']))
+        return content.getvalue()

=== added file 'cloudinit/net/sysconfig.py'
--- cloudinit/net/sysconfig.py	1970-01-01 00:00:00 +0000
+++ cloudinit/net/sysconfig.py	2016-06-15 23:16:02 +0000
@@ -0,0 +1,400 @@
+# vi: ts=4 expandtab
+#
+#    This program is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU General Public License version 3, as
+#    published by the Free Software Foundation.
+#
+#    This program is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    GNU General Public License for more details.
+#
+#    You should have received a copy of the GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import os
+import re
+
+import six
+
+from cloudinit.distros.parsers import resolv_conf
+from cloudinit import util
+
+from . import renderer
+
+
+def _make_header(sep='#'):
+    lines = [
+        "Created by cloud-init on instance boot automatically, do not edit.",
+        "",
+    ]
+    for i in range(0, len(lines)):
+        if lines[i]:
+            lines[i] = sep + " " + lines[i]
+        else:
+            lines[i] = sep
+    return "\n".join(lines)
+
+
+def _is_default_route(route):
+    if route['network'] == '::' and route['netmask'] == 0:
+        return True
+    if route['network'] == '0.0.0.0' and route['netmask'] == '0.0.0.0':
+        return True
+    return False
+
+
+def _quote_value(value):
+    if re.search(r"\s", value):
+        # This doesn't handle complex cases...
+        if value.startswith('"') and value.endswith('"'):
+            return value
+        else:
+            return '"%s"' % value
+    else:
+        return value
+
+
+class ConfigMap(object):
+    """Sysconfig like dictionary object."""
+
+    # Why does redhat prefer yes/no to true/false??
+    _bool_map = {
+        True: 'yes',
+        False: 'no',
+    }
+
+    def __init__(self):
+        self._conf = {}
+
+    def __setitem__(self, key, value):
+        self._conf[key] = value
+
+    def drop(self, key):
+        self._conf.pop(key, None)
+
+    def __len__(self):
+        return len(self._conf)
+
+    def to_string(self):
+        buf = six.StringIO()
+        buf.write(_make_header())
+        if self._conf:
+            buf.write("\n")
+        for key in sorted(self._conf.keys()):
+            value = self._conf[key]
+            if isinstance(value, bool):
+                value = self._bool_map[value]
+            if not isinstance(value, six.string_types):
+                value = str(value)
+            buf.write("%s=%s\n" % (key, _quote_value(value)))
+        return buf.getvalue()
+
+
+class Route(ConfigMap):
+    """Represents a route configuration."""
+
+    route_fn_tpl = '%(base)s/network-scripts/route-%(name)s'
+
+    def __init__(self, route_name, base_sysconf_dir):
+        super(Route, self).__init__()
+        self.last_idx = 1
+        self.has_set_default = False
+        self._route_name = route_name
+        self._base_sysconf_dir = base_sysconf_dir
+
+    def copy(self):
+        r = Route(self._route_name, self._base_sysconf_dir)
+        r._conf = self._conf.copy()
+        r.last_idx = self.last_idx
+        r.has_set_default = self.has_set_default
+        return r
+
+    @property
+    def path(self):
+        return self.route_fn_tpl % ({'base': self._base_sysconf_dir,
+                                     'name': self._route_name})
+
+
+class NetInterface(ConfigMap):
+    """Represents a sysconfig/networking-script (and its config + children)."""
+
+    iface_fn_tpl = '%(base)s/network-scripts/ifcfg-%(name)s'
+
+    iface_types = {
+        'ethernet': 'Ethernet',
+        'bond': 'Bond',
+        'bridge': 'Bridge',
+    }
+
+    def __init__(self, iface_name, base_sysconf_dir, kind='ethernet'):
+        super(NetInterface, self).__init__()
+        self.children = []
+        self.routes = Route(iface_name, base_sysconf_dir)
+        self._kind = kind
+        self._iface_name = iface_name
+        self._conf['DEVICE'] = iface_name
+        self._conf['TYPE'] = self.iface_types[kind]
+        self._base_sysconf_dir = base_sysconf_dir
+
+    @property
+    def name(self):
+        return self._iface_name
+
+    @name.setter
+    def name(self, iface_name):
+        self._iface_name = iface_name
+        self._conf['DEVICE'] = iface_name
+
+    @property
+    def kind(self):
+        return self._kind
+
+    @kind.setter
+    def kind(self, kind):
+        self._kind = kind
+        self._conf['TYPE'] = self.iface_types[kind]
+
+    @property
+    def path(self):
+        return self.iface_fn_tpl % ({'base': self._base_sysconf_dir,
+                                     'name': self.name})
+
+    def copy(self, copy_children=False, copy_routes=False):
+        c = NetInterface(self.name, self._base_sysconf_dir, kind=self._kind)
+        c._conf = self._conf.copy()
+        if copy_children:
+            c.children = list(self.children)
+        if copy_routes:
+            c.routes = self.routes.copy()
+        return c
+
+
+class Renderer(renderer.Renderer):
+    """Renders network information in a /etc/sysconfig format."""
+
+    # See: https://access.redhat.com/documentation/en-US/\
+    #      Red_Hat_Enterprise_Linux/6/html/Deployment_Guide/\
+    #      s1-networkscripts-interfaces.html (or other docs for
+    #                                         details about this)
+
+    iface_defaults = tuple([
+        ('ONBOOT', True),
+        ('USERCTL', False),
+        ('NM_CONTROLLED', False),
+        ('BOOTPROTO', 'none'),
+    ])
+
+    # If these keys exist, then there values will be used to form
+    # a BONDING_OPTS grouping; otherwise no grouping will be set.
+    bond_tpl_opts = tuple([
+        ('bond_mode', "mode=%s"),
+        ('bond_xmit_hash_policy', "xmit_hash_policy=%s"),
+        ('bond_miimon', "miimon=%s"),
+    ])
+
+    bridge_opts_keys = tuple([
+        ('bridge_stp', 'STP'),
+        ('bridge_ageing', 'AGEING'),
+        ('bridge_bridgeprio', 'PRIO'),
+    ])
+
+    def __init__(self, config=None):
+        if not config:
+            config = {}
+        self.sysconf_dir = config.get('sysconf_dir', 'etc/sysconfig/')
+        self.netrules_path = config.get(
+            'netrules_path', 'etc/udev/rules.d/70-persistent-net.rules')
+        self.dns_path = config.get('dns_path', 'etc/resolv.conf')
+
+    @classmethod
+    def _render_iface_shared(cls, iface, iface_cfg):
+        for k, v in cls.iface_defaults:
+            iface_cfg[k] = v
+        for (old_key, new_key) in [('mac_address', 'HWADDR'), ('mtu', 'MTU')]:
+            old_value = iface.get(old_key)
+            if old_value is not None:
+                iface_cfg[new_key] = old_value
+
+    @classmethod
+    def _render_subnet(cls, iface_cfg, route_cfg, subnet):
+        subnet_type = subnet.get('type')
+        if subnet_type == 'dhcp6':
+            iface_cfg['DHCPV6C'] = True
+            iface_cfg['IPV6INIT'] = True
+            iface_cfg['BOOTPROTO'] = 'dhcp'
+        elif subnet_type in ['dhcp4', 'dhcp']:
+            iface_cfg['BOOTPROTO'] = 'dhcp'
+        elif subnet_type == 'static':
+            iface_cfg['BOOTPROTO'] = 'static'
+            if subnet.get('ipv6'):
+                iface_cfg['IPV6ADDR'] = subnet['address']
+                iface_cfg['IPV6INIT'] = True
+            else:
+                iface_cfg['IPADDR'] = subnet['address']
+        else:
+            raise ValueError("Unknown subnet type '%s' found"
+                             " for interface '%s'" % (subnet_type,
+                                                      iface_cfg.name))
+        if 'netmask' in subnet:
+            iface_cfg['NETMASK'] = subnet['netmask']
+        for route in subnet.get('routes', []):
+            if _is_default_route(route):
+                if route_cfg.has_set_default:
+                    raise ValueError("Duplicate declaration of default"
+                                     " route found for interface '%s'"
+                                     % (iface_cfg.name))
+                # NOTE(harlowja): ipv6 and ipv4 default gateways
+                gw_key = 'GATEWAY0'
+                nm_key = 'NETMASK0'
+                addr_key = 'ADDRESS0'
+                # The owning interface provides the default route.
+                #
+                # TODO(harlowja): add validation that no other iface has
+                # also provided the default route?
+                iface_cfg['DEFROUTE'] = True
+                if 'gateway' in route:
+                    iface_cfg['GATEWAY'] = route['gateway']
+                route_cfg.has_set_default = True
+            else:
+                gw_key = 'GATEWAY%s' % route_cfg.last_idx
+                nm_key = 'NETMASK%s' % route_cfg.last_idx
+                addr_key = 'ADDRESS%s' % route_cfg.last_idx
+                route_cfg.last_idx += 1
+            for (old_key, new_key) in [('gateway', gw_key),
+                                       ('netmask', nm_key),
+                                       ('network', addr_key)]:
+                if old_key in route:
+                    route_cfg[new_key] = route[old_key]
+
+    @classmethod
+    def _render_bonding_opts(cls, iface_cfg, iface):
+        bond_opts = []
+        for (bond_key, value_tpl) in cls.bond_tpl_opts:
+            # Seems like either dash or underscore is possible?
+            bond_keys = [bond_key, bond_key.replace("_", "-")]
+            for bond_key in bond_keys:
+                if bond_key in iface:
+                    bond_value = iface[bond_key]
+                    if isinstance(bond_value, (tuple, list)):
+                        bond_value = " ".join(bond_value)
+                    bond_opts.append(value_tpl % (bond_value))
+                    break
+        if bond_opts:
+            iface_cfg['BONDING_OPTS'] = " ".join(bond_opts)
+
+    @classmethod
+    def _render_physical_interfaces(cls, network_state, iface_contents):
+        physical_filter = renderer.filter_by_physical
+        for iface in network_state.iter_interfaces(physical_filter):
+            iface_name = iface['name']
+            iface_subnets = iface.get("subnets", [])
+            iface_cfg = iface_contents[iface_name]
+            route_cfg = iface_cfg.routes
+            if len(iface_subnets) == 1:
+                cls._render_subnet(iface_cfg, route_cfg, iface_subnets[0])
+            elif len(iface_subnets) > 1:
+                for i, iface_subnet in enumerate(iface_subnets,
+                                                 start=len(iface.children)):
+                    iface_sub_cfg = iface_cfg.copy()
+                    iface_sub_cfg.name = "%s:%s" % (iface_name, i)
+                    iface.children.append(iface_sub_cfg)
+                    cls._render_subnet(iface_sub_cfg, route_cfg, iface_subnet)
+
+    @classmethod
+    def _render_bond_interfaces(cls, network_state, iface_contents):
+        bond_filter = renderer.filter_by_type('bond')
+        for iface in network_state.iter_interfaces(bond_filter):
+            iface_name = iface['name']
+            iface_cfg = iface_contents[iface_name]
+            cls._render_bonding_opts(iface_cfg, iface)
+            iface_master_name = iface['bond-master']
+            iface_cfg['MASTER'] = iface_master_name
+            iface_cfg['SLAVE'] = True
+            # Ensure that the master interface (and any of its children)
+            # are actually marked as being bond types...
+            master_cfg = iface_contents[iface_master_name]
+            master_cfgs = [master_cfg]
+            master_cfgs.extend(master_cfg.children)
+            for master_cfg in master_cfgs:
+                master_cfg['BONDING_MASTER'] = True
+                master_cfg.kind = 'bond'
+
+    @staticmethod
+    def _render_vlan_interfaces(network_state, iface_contents):
+        vlan_filter = renderer.filter_by_type('vlan')
+        for iface in network_state.iter_interfaces(vlan_filter):
+            iface_name = iface['name']
+            iface_cfg = iface_contents[iface_name]
+            iface_cfg['VLAN'] = True
+            iface_cfg['PHYSDEV'] = iface_name[:iface_name.rfind('.')]
+
+    @staticmethod
+    def _render_dns(network_state, existing_dns_path=None):
+        content = resolv_conf.ResolvConf("")
+        if existing_dns_path and os.path.isfile(existing_dns_path):
+            content = resolv_conf.ResolvConf(util.load_file(existing_dns_path))
+        for nameserver in network_state.dns_nameservers:
+            content.add_nameserver(nameserver)
+        for searchdomain in network_state.dns_searchdomains:
+            content.add_search_domain(searchdomain)
+        return "\n".join([_make_header(';'), str(content)])
+
+    @classmethod
+    def _render_bridge_interfaces(cls, network_state, iface_contents):
+        bridge_filter = renderer.filter_by_type('bridge')
+        for iface in network_state.iter_interfaces(bridge_filter):
+            iface_name = iface['name']
+            iface_cfg = iface_contents[iface_name]
+            iface_cfg.kind = 'bridge'
+            for old_key, new_key in cls.bridge_opts_keys:
+                if old_key in iface:
+                    iface_cfg[new_key] = iface[old_key]
+            # Is this the right key to get all the connected interfaces?
+            for bridged_iface_name in iface.get('bridge_ports', []):
+                # Ensure all bridged interfaces are correctly tagged
+                # as being bridged to this interface.
+                bridged_cfg = iface_contents[bridged_iface_name]
+                bridged_cfgs = [bridged_cfg]
+                bridged_cfgs.extend(bridged_cfg.children)
+                for bridge_cfg in bridged_cfgs:
+                    bridge_cfg['BRIDGE'] = iface_name
+
+    @classmethod
+    def _render_sysconfig(cls, base_sysconf_dir, network_state):
+        '''Given state, return /etc/sysconfig files + contents'''
+        iface_contents = {}
+        for iface in network_state.iter_interfaces():
+            iface_name = iface['name']
+            iface_cfg = NetInterface(iface_name, base_sysconf_dir)
+            cls._render_iface_shared(iface, iface_cfg)
+            iface_contents[iface_name] = iface_cfg
+        cls._render_physical_interfaces(network_state, iface_contents)
+        cls._render_bond_interfaces(network_state, iface_contents)
+        cls._render_vlan_interfaces(network_state, iface_contents)
+        cls._render_bridge_interfaces(network_state, iface_contents)
+        contents = {}
+        for iface_name, iface_cfg in iface_contents.items():
+            if iface_cfg or iface_cfg.children:
+                contents[iface_cfg.path] = iface_cfg.to_string()
+                for iface_cfg in iface_cfg.children:
+                    if iface_cfg:
+                        contents[iface_cfg.path] = iface_cfg.to_string()
+            if iface_cfg.routes:
+                contents[iface_cfg.routes.path] = iface_cfg.routes.to_string()
+        return contents
+
+    def render_network_state(self, target, network_state):
+        base_sysconf_dir = os.path.join(target, self.sysconf_dir)
+        for path, data in self._render_sysconfig(base_sysconf_dir,
+                                                 network_state).items():
+            util.write_file(path, data)
+        if self.dns_path:
+            dns_path = os.path.join(target, self.dns_path)
+            resolv_content = self._render_dns(network_state,
+                                              existing_dns_path=dns_path)
+            util.write_file(dns_path, resolv_content)
+        if self.netrules_path:
+            netrules_content = self._render_persistent_net(network_state)
+            netrules_path = os.path.join(target, self.netrules_path)
+            util.write_file(netrules_path, netrules_content)

=== modified file 'tests/unittests/test_net.py'
--- tests/unittests/test_net.py	2016-05-19 22:33:15 +0000
+++ tests/unittests/test_net.py	2016-06-15 23:16:02 +0000
@@ -2,6 +2,8 @@
 from cloudinit.net import cmdline
 from cloudinit.net import eni
 from cloudinit.net import network_state
+from cloudinit.net import sysconfig
+from cloudinit.sources.helpers import openstack
 from cloudinit import util
 
 from .helpers import mock
@@ -74,6 +76,157 @@
                  'dns_nameservers': ['10.0.1.1']}],
 }
 
+# Examples (and expected outputs for various renderers).
+OS_SAMPLES = [
+    {
+        'in_data': {
+            "services": [{"type": "dns", "address": "172.19.0.12"}],
+            "networks": [{
+                "network_id": "dacd568d-5be6-4786-91fe-750c374b78b4",
+                "type": "ipv4", "netmask": "255.255.252.0",
+                "link": "tap1a81968a-79",
+                "routes": [{
+                    "netmask": "0.0.0.0",
+                    "network": "0.0.0.0",
+                    "gateway": "172.19.3.254",
+                }],
+                "ip_address": "172.19.1.34", "id": "network0"
+            }],
+            "links": [
+                {
+                    "ethernet_mac_address": "fa:16:3e:ed:9a:59",
+                    "mtu": None, "type": "bridge", "id":
+                    "tap1a81968a-79",
+                    "vif_id": "1a81968a-797a-400f-8a80-567f997eb93f"
+                },
+            ],
+        },
+        'in_macs': {
+            'fa:16:3e:ed:9a:59': 'eth0',
+        },
+        'out_sysconfig': [
+            ('etc/sysconfig/network-scripts/ifcfg-eth0',
+             """
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+BOOTPROTO=static
+DEFROUTE=yes
+DEVICE=eth0
+GATEWAY=172.19.3.254
+HWADDR=fa:16:3e:ed:9a:59
+IPADDR=172.19.1.34
+NETMASK=255.255.252.0
+NM_CONTROLLED=no
+ONBOOT=yes
+TYPE=Ethernet
+USERCTL=no
+""".lstrip()),
+            ('etc/sysconfig/network-scripts/route-eth0',
+             """
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+ADDRESS0=0.0.0.0
+GATEWAY0=172.19.3.254
+NETMASK0=0.0.0.0
+""".lstrip()),
+            ('etc/resolv.conf',
+             """
+; Created by cloud-init on instance boot automatically, do not edit.
+;
+nameserver 172.19.0.12
+""".lstrip()),
+            ('etc/udev/rules.d/70-persistent-net.rules',
+             "".join(['SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ',
+                      'ATTR{address}=="fa:16:3e:ed:9a:59", NAME="eth0"\n']))]
+    }
+]
+
+
+def _setup_test(tmp_dir, mock_get_devicelist, mock_sys_netdev_info,
+                mock_sys_dev_path):
+    mock_get_devicelist.return_value = ['eth1000']
+    dev_characteristics = {
+        'eth1000': {
+            "bridge": False,
+            "carrier": False,
+            "dormant": False,
+            "operstate": "down",
+            "address": "07-1C-C6-75-A4-BE",
+        }
+    }
+
+    def netdev_info(name, field):
+        return dev_characteristics[name][field]
+
+    mock_sys_netdev_info.side_effect = netdev_info
+
+    def sys_dev_path(devname, path=""):
+        return tmp_dir + devname + "/" + path
+
+    for dev in dev_characteristics:
+        os.makedirs(os.path.join(tmp_dir, dev))
+        with open(os.path.join(tmp_dir, dev, 'operstate'), 'w') as fh:
+            fh.write("down")
+
+    mock_sys_dev_path.side_effect = sys_dev_path
+
+
+class TestSysConfigRendering(TestCase):
+
+    @mock.patch("cloudinit.net.sys_dev_path")
+    @mock.patch("cloudinit.net.sys_netdev_info")
+    @mock.patch("cloudinit.net.get_devicelist")
+    def test_default_generation(self, mock_get_devicelist,
+                                mock_sys_netdev_info,
+                                mock_sys_dev_path):
+        tmp_dir = tempfile.mkdtemp()
+        self.addCleanup(shutil.rmtree, tmp_dir)
+        _setup_test(tmp_dir, mock_get_devicelist,
+                    mock_sys_netdev_info, mock_sys_dev_path)
+
+        network_cfg = net.generate_fallback_config()
+        ns = network_state.parse_net_config_data(network_cfg,
+                                                 skip_broken=False)
+
+        render_dir = os.path.join(tmp_dir, "render")
+        os.makedirs(render_dir)
+
+        renderer = sysconfig.Renderer()
+        renderer.render_network_state(render_dir, ns)
+
+        render_file = 'etc/sysconfig/network-scripts/ifcfg-eth1000'
+        with open(os.path.join(render_dir, render_file)) as fh:
+            content = fh.read()
+            expected_content = """
+# Created by cloud-init on instance boot automatically, do not edit.
+#
+BOOTPROTO=dhcp
+DEVICE=eth1000
+HWADDR=07-1C-C6-75-A4-BE
+NM_CONTROLLED=no
+ONBOOT=yes
+TYPE=Ethernet
+USERCTL=no
+""".lstrip()
+            self.assertEqual(expected_content, content)
+
+    def test_openstack_rendering_samples(self):
+        tmp_dir = tempfile.mkdtemp()
+        self.addCleanup(shutil.rmtree, tmp_dir)
+        render_dir = os.path.join(tmp_dir, "render")
+        for os_sample in OS_SAMPLES:
+            ex_input = os_sample['in_data']
+            ex_mac_addrs = os_sample['in_macs']
+            network_cfg = openstack.convert_net_json(
+                ex_input, known_macs=ex_mac_addrs)
+            ns = network_state.parse_net_config_data(network_cfg,
+                                                     skip_broken=False)
+            renderer = sysconfig.Renderer()
+            renderer.render_network_state(render_dir, ns)
+            for fn, expected_content in os_sample.get('out_sysconfig', []):
+                with open(os.path.join(render_dir, fn)) as fh:
+                    self.assertEqual(expected_content, fh.read())
+
 
 class TestEniNetRendering(TestCase):
 
@@ -83,35 +236,10 @@
     def test_default_generation(self, mock_get_devicelist,
                                 mock_sys_netdev_info,
                                 mock_sys_dev_path):
-        mock_get_devicelist.return_value = ['eth1000', 'lo']
-
-        dev_characteristics = {
-            'eth1000': {
-                "bridge": False,
-                "carrier": False,
-                "dormant": False,
-                "operstate": "down",
-                "address": "07-1C-C6-75-A4-BE",
-            }
-        }
-
-        def netdev_info(name, field):
-            return dev_characteristics[name][field]
-
-        mock_sys_netdev_info.side_effect = netdev_info
-
         tmp_dir = tempfile.mkdtemp()
         self.addCleanup(shutil.rmtree, tmp_dir)
-
-        def sys_dev_path(devname, path=""):
-            return tmp_dir + devname + "/" + path
-
-        for dev in dev_characteristics:
-            os.makedirs(os.path.join(tmp_dir, dev))
-            with open(os.path.join(tmp_dir, dev, 'operstate'), 'w') as fh:
-                fh.write("down")
-
-        mock_sys_dev_path.side_effect = sys_dev_path
+        _setup_test(tmp_dir, mock_get_devicelist,
+                    mock_sys_netdev_info, mock_sys_dev_path)
 
         network_cfg = net.generate_fallback_config()
         ns = network_state.parse_net_config_data(network_cfg,
@@ -120,11 +248,11 @@
         render_dir = os.path.join(tmp_dir, "render")
         os.makedirs(render_dir)
 
-        renderer = eni.Renderer()
-        renderer.render_network_state(render_dir, ns,
-                                      eni="interfaces",
-                                      links_prefix=None,
-                                      netrules=None)
+        renderer = eni.Renderer(
+            {'links_path_prefix': None,
+             'eni_path': 'interfaces', 'netrules_path': None,
+             })
+        renderer.render_network_state(render_dir, ns)
 
         self.assertTrue(os.path.exists(os.path.join(render_dir,
                                                     'interfaces')))