Refactor a large part of the networking code.

Splits off distro specific code into specific files so that
other kinds of networking configuration can be written by the
various distro(s) that cloud-init supports.

It also isolates some of the cloudinit.net code so that it can
be more easily used on its own (and incorporated into other
projects such as curtin).

During this process it adds tests so that the net process can
be tested (to some level) so that the format conversion processes
can be tested going forward.

1 files changed, 84 insertions, 11 deletions

diff --git a/tests/unittests/test_net.py b/tests/unittests/test_net.py
index 624a9aa8..7998111a 100644
--- a/tests/unittests/test_net.py
+++ b/tests/unittests/test_net.py
@@ -1,6 +1,10 @@
 from cloudinit import net
+from cloudinit.net import cmdline
+from cloudinit.net import eni
+from cloudinit.net import network_state
 from cloudinit import util
 
+from .helpers import mock
 from .helpers import TestCase
 
 import base64
@@ -9,6 +13,8 @@ import gzip
 import io
 import json
 import os
+import shutil
+import tempfile
 
 DHCP_CONTENT_1 = """
 DEVICE='eth0'
@@ -69,21 +75,87 @@ STATIC_EXPECTED_1 = {
 }
 
 
-class TestNetConfigParsing(TestCase):
+class TestEniNetRendering(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):
+        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
+
+        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 = eni.Renderer()
+        renderer.render_network_state(render_dir, ns,
+                                      eni="interfaces",
+                                      links_prefix=None,
+                                      netrules=None)
+
+        self.assertTrue(os.path.exists(os.path.join(render_dir,
+                                                    'interfaces')))
+        with open(os.path.join(render_dir, 'interfaces')) as fh:
+            contents = fh.read()
+
+        expected = """
+auto lo
+iface lo inet loopback
+
+auto eth1000
+iface eth1000 inet dhcp
+"""
+        self.assertEqual(expected.lstrip(), contents.lstrip())
+
+
+class TestCmdlineConfigParsing(TestCase):
     simple_cfg = {
         'config': [{"type": "physical", "name": "eth0",
                     "mac_address": "c0:d6:9f:2c:e8:80",
                     "subnets": [{"type": "dhcp"}]}]}
 
-    def test_klibc_convert_dhcp(self):
-        found = net._klibc_to_config_entry(DHCP_CONTENT_1)
+    def test_cmdline_convert_dhcp(self):
+        found = cmdline._klibc_to_config_entry(DHCP_CONTENT_1)
         self.assertEqual(found, ('eth0', DHCP_EXPECTED_1))
 
-    def test_klibc_convert_static(self):
-        found = net._klibc_to_config_entry(STATIC_CONTENT_1)
+    def test_cmdline_convert_static(self):
+        found = cmdline._klibc_to_config_entry(STATIC_CONTENT_1)
         self.assertEqual(found, ('eth1', STATIC_EXPECTED_1))
 
-    def test_config_from_klibc_net_cfg(self):
+    def test_config_from_cmdline_net_cfg(self):
         files = []
         pairs = (('net-eth0.cfg', DHCP_CONTENT_1),
                  ('net-eth1.cfg', STATIC_CONTENT_1))
@@ -104,21 +176,22 @@ class TestNetConfigParsing(TestCase):
                 files.append(fp)
                 util.write_file(fp, content)
 
-            found = net.config_from_klibc_net_cfg(files=files, mac_addrs=macs)
+            found = cmdline.config_from_klibc_net_cfg(files=files,
+                                                      mac_addrs=macs)
             self.assertEqual(found, expected)
 
     def test_cmdline_with_b64(self):
         data = base64.b64encode(json.dumps(self.simple_cfg).encode())
         encoded_text = data.decode()
-        cmdline = 'ro network-config=' + encoded_text + ' root=foo'
-        found = net.read_kernel_cmdline_config(cmdline=cmdline)
+        raw_cmdline = 'ro network-config=' + encoded_text + ' root=foo'
+        found = cmdline.read_kernel_cmdline_config(cmdline=raw_cmdline)
         self.assertEqual(found, self.simple_cfg)
 
     def test_cmdline_with_b64_gz(self):
         data = _gzip_data(json.dumps(self.simple_cfg).encode())
         encoded_text = base64.b64encode(data).decode()
-        cmdline = 'ro network-config=' + encoded_text + ' root=foo'
-        found = net.read_kernel_cmdline_config(cmdline=cmdline)
+        raw_cmdline = 'ro network-config=' + encoded_text + ' root=foo'
+        found = cmdline.read_kernel_cmdline_config(cmdline=raw_cmdline)
         self.assertEqual(found, self.simple_cfg)