net: Make sysconfig renderer compatible with Network Manager.

The 'sysconfig' renderer is activated if, and only if, there's ifup and
ifdown commands present in its search dictonary or the network-scripts
configuration files are found. This patch adds a check for Network-
Manager configuration file as well.

This solution is based on the use of the plugin 'ifcfg-rh' present in
Network-Manager and is designed to support Fedora 29 or other
distributions that also replaced network-scripts by Network-Manager.

2 files changed, 107 insertions, 0 deletions

diff --git a/cloudinit/net/sysconfig.py b/cloudinit/net/sysconfig.py
index 17293e1d..ae41f7b3 100644
--- a/cloudinit/net/sysconfig.py
+++ b/cloudinit/net/sysconfig.py
@@ -10,11 +10,14 @@ from cloudinit.distros.parsers import resolv_conf
 from cloudinit import log as logging
 from cloudinit import util
 
+from configobj import ConfigObj
+
 from . import renderer
 from .network_state import (
     is_ipv6_addr, net_prefix_to_ipv4_mask, subnet_is_ipv6)
 
 LOG = logging.getLogger(__name__)
+NM_CFG_FILE = "/etc/NetworkManager/NetworkManager.conf"
 
 
 def _make_header(sep='#'):
@@ -46,6 +49,24 @@ def _quote_value(value):
         return value
 
 
+def enable_ifcfg_rh(path):
+    """Add ifcfg-rh to NetworkManager.cfg plugins if main section is present"""
+    config = ConfigObj(path)
+    if 'main' in config:
+        if 'plugins' in config['main']:
+            if 'ifcfg-rh' in config['main']['plugins']:
+                return
+        else:
+            config['main']['plugins'] = []
+
+        if isinstance(config['main']['plugins'], list):
+            config['main']['plugins'].append('ifcfg-rh')
+        else:
+            config['main']['plugins'] = [config['main']['plugins'], 'ifcfg-rh']
+        config.write()
+        LOG.debug('Enabled ifcfg-rh NetworkManager plugins')
+
+
 class ConfigMap(object):
     """Sysconfig like dictionary object."""
 
@@ -657,6 +678,8 @@ class Renderer(renderer.Renderer):
             netrules_content = self._render_persistent_net(network_state)
             netrules_path = util.target_path(target, self.netrules_path)
             util.write_file(netrules_path, netrules_content, file_mode)
+        if available_nm(target=target):
+            enable_ifcfg_rh(util.target_path(target, path=NM_CFG_FILE))
 
         sysconfig_path = util.target_path(target, templates.get('control'))
         # Distros configuring /etc/sysconfig/network as a file e.g. Centos
@@ -671,6 +694,13 @@ class Renderer(renderer.Renderer):
 
 
 def available(target=None):
+    sysconfig = available_sysconfig(target=target)
+    nm = available_nm(target=target)
+
+    return any([nm, sysconfig])
+
+
+def available_sysconfig(target=None):
     expected = ['ifup', 'ifdown']
     search = ['/sbin', '/usr/sbin']
     for p in expected:
@@ -686,4 +716,10 @@ def available(target=None):
     return True
 
 
+def available_nm(target=None):
+    if not os.path.isfile(util.target_path(target, path=NM_CFG_FILE)):
+        return False
+    return True
+
+
 # vi: ts=4 expandtab
diff --git a/tests/unittests/test_net.py b/tests/unittests/test_net.py
index 195f261c..d679e92c 100644
--- a/tests/unittests/test_net.py
+++ b/tests/unittests/test_net.py
@@ -22,6 +22,7 @@ import os
 import textwrap
 import yaml
 
+
 DHCP_CONTENT_1 = """
 DEVICE='eth0'
 PROTO='dhcp'
@@ -1880,6 +1881,7 @@ class TestRhelSysConfigRendering(CiTestCase):
 
     with_logs = True
 
+    nm_cfg_file = "/etc/NetworkManager/NetworkManager.conf"
     scripts_dir = '/etc/sysconfig/network-scripts'
     header = ('# Created by cloud-init on instance boot automatically, '
               'do not edit.\n#\n')
@@ -2174,6 +2176,75 @@ USERCTL=no
         self._compare_files_to_expected(entry[self.expected_name], found)
         self._assert_headers(found)
 
+    def test_check_ifcfg_rh(self):
+        """ifcfg-rh plugin is added NetworkManager.conf if conf present."""
+        render_dir = self.tmp_dir()
+        nm_cfg = util.target_path(render_dir, path=self.nm_cfg_file)
+        util.ensure_dir(os.path.dirname(nm_cfg))
+
+        # write a template nm.conf, note plugins is a list here
+        with open(nm_cfg, 'w') as fh:
+            fh.write('# test_check_ifcfg_rh\n[main]\nplugins=foo,bar\n')
+        self.assertTrue(os.path.exists(nm_cfg))
+
+        # render and read
+        entry = NETWORK_CONFIGS['small']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']),
+                                      dir=render_dir)
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+
+        # check ifcfg-rh is in the 'plugins' list
+        config = sysconfig.ConfigObj(nm_cfg)
+        self.assertIn('ifcfg-rh', config['main']['plugins'])
+
+    def test_check_ifcfg_rh_plugins_string(self):
+        """ifcfg-rh plugin is append when plugins is a string."""
+        render_dir = self.tmp_path("render")
+        os.makedirs(render_dir)
+        nm_cfg = util.target_path(render_dir, path=self.nm_cfg_file)
+        util.ensure_dir(os.path.dirname(nm_cfg))
+
+        # write a template nm.conf, note plugins is a value here
+        util.write_file(nm_cfg, '# test_check_ifcfg_rh\n[main]\nplugins=foo\n')
+
+        # render and read
+        entry = NETWORK_CONFIGS['small']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']),
+                                      dir=render_dir)
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+
+        # check raw content has plugin
+        nm_file_content = util.load_file(nm_cfg)
+        self.assertIn('ifcfg-rh', nm_file_content)
+
+        # check ifcfg-rh is in the 'plugins' list
+        config = sysconfig.ConfigObj(nm_cfg)
+        self.assertIn('ifcfg-rh', config['main']['plugins'])
+
+    def test_check_ifcfg_rh_plugins_no_plugins(self):
+        """enable_ifcfg_plugin creates plugins value if missing."""
+        render_dir = self.tmp_path("render")
+        os.makedirs(render_dir)
+        nm_cfg = util.target_path(render_dir, path=self.nm_cfg_file)
+        util.ensure_dir(os.path.dirname(nm_cfg))
+
+        # write a template nm.conf, note plugins is missing
+        util.write_file(nm_cfg, '# test_check_ifcfg_rh\n[main]\n')
+        self.assertTrue(os.path.exists(nm_cfg))
+
+        # render and read
+        entry = NETWORK_CONFIGS['small']
+        found = self._render_and_read(network_config=yaml.load(entry['yaml']),
+                                      dir=render_dir)
+        self._compare_files_to_expected(entry[self.expected_name], found)
+        self._assert_headers(found)
+
+        # check ifcfg-rh is in the 'plugins' list
+        config = sysconfig.ConfigObj(nm_cfg)
+        self.assertIn('ifcfg-rh', config['main']['plugins'])
+
 
 class TestOpenSuseSysConfigRendering(CiTestCase):