Merge lp:~blake-rouse/curtin/net-interfaces-parser into lp:~curtin-dev/curtin/trunk

[Blake Rouse]

Add /etc/network/interfaces file parser utility.

Provides a nice method to parse an /etc/network/interfaces file. Since this is the file format that is passed to the hook commands, it makes it easy for any python hook command, to parse the file. This could easily be included in each curtin image, but adding it to curtin removes the need to have it per image.

[lp:~blake-rouse/curtin/net-interfaces-parser]

136. By Blake Rouse on 2014-06-16

Support source-directory and source for /etc/network/interfaces.

137. By Blake Rouse on 2014-06-24

Add tests for net interface parser.

138. By Blake Rouse on 2014-06-24

Merge trunk.

[Blake Rouse (blake-rouse)]

Added the ability to handle source and source-directory. Added test coverage.

=== modified file 'curtin/net/__init__.py'
--- curtin/net/__init__.py	2014-03-25 23:13:46 +0000
+++ curtin/net/__init__.py	2014-06-24 17:55:55 +0000
@@ -1,6 +1,7 @@
-#   Copyright (C) 2013 Canonical Ltd.
+#   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
@@ -22,6 +23,22 @@
 
 SYS_CLASS_NET = "/sys/class/net/"
 
+NET_CONFIG_OPTIONS = [
+    "address", "netmask", "broadcast", "network", "metric", "gateway",
+    "pointtopoint", "media", "mtu", "hostname", "leasehours", "leasetime",
+    "vendor", "client", "bootfile", "server", "hwaddr", "provider", "frame",
+    "netnum", "endpoint", "local", "ttl",
+    ]
+
+NET_CONFIG_COMMANDS = [
+    "pre-up", "up", "post-up", "down", "pre-down", "post-down",
+    ]
+
+NET_CONFIG_BRIDGE_OPTIONS = [
+    "bridge_ageing", "bridge_bridgeprio", "bridge_fd", "bridge_gcinit",
+    "bridge_hello", "bridge_maxage", "bridge_maxwait", "bridge_stp",
+    ]
+
 
 def sys_dev_path(devname, path=""):
     return SYS_CLASS_NET + devname + "/" + path
@@ -95,4 +112,100 @@
     return os.listdir(SYS_CLASS_NET)
 
 
+class ParserError(Exception):
+    """Raised when parser has issue parsing the interfaces file."""
+
+
+def parse_deb_config_data(ifaces, contents, path):
+    """Parses the file contents, placing result into ifaces.
+
+    :param ifaces: interface dictionary
+    :param contents: contents of interfaces file
+    :param path: directory interfaces file was located
+    """
+    currif = None
+    src_dir = path
+    for line in contents.splitlines():
+        line = line.strip()
+        if line.startswith('#'):
+            continue
+        split = line.split(' ')
+        option = split[0]
+        if option == "source-directory":
+            src_dir = os.path.join(path, split[1])
+        elif option == "source":
+            src_path = os.path.join(src_dir, split[1])
+            with open(src_path, "r") as fp:
+                src_data = fp.read().strip()
+            parse_deb_config_data(
+                ifaces, src_data,
+                os.path.dirname(os.path.abspath(src_path)))
+        elif option == "auto":
+            for iface in split[1:]:
+                if iface not in ifaces:
+                    ifaces[iface] = {}
+                ifaces[iface]['auto'] = True
+        elif option == "iface":
+            iface, family, method = split[1:4]
+            if iface not in ifaces:
+                ifaces[iface] = {}  
+            elif 'family' in ifaces[iface]:
+                raise ParserError("Cannot define %s interface again.")
+            ifaces[iface]['family'] = family
+            ifaces[iface]['method'] = method
+            currif = iface
+        elif option == "hwaddress":
+            ifaces[currif]['hwaddress'] = split[1]
+        elif option in NET_CONFIG_OPTIONS:
+            ifaces[currif][option] = split[1]
+        elif option in NET_CONFIG_COMMANDS:
+            if option not in ifaces[currif]:
+                ifaces[currif][option] = []
+            ifaces[currif][option].append(' '.join(split[1:]))
+        elif option.startswith('dns-'):
+            if 'dns' not in ifaces[currif]:
+                ifaces[currif]['dns'] = {}
+            if option == 'dns-search':
+                ifaces[currif]['dns']['search'] = []
+                for domain in split[1:]:
+                    ifaces[currif]['dns']['search'].append(domain)
+            elif option == 'dns-nameservers':
+                ifaces[currif]['dns']['nameservers'] = []
+                for server in split[1:]:
+                    ifaces[currif]['dns']['nameservers'].append(server)
+        elif option.startswith('bridge_'):
+            if 'bridge' not in ifaces[currif]:
+                ifaces[currif]['bridge'] = {}
+            if option in NET_CONFIG_BRIDGE_OPTIONS:
+                bridge_option = option.replace('bridge_', '')
+                ifaces[currif]['bridge'][bridge_option] = split[1]
+            elif option == "bridge_ports":
+                ifaces[currif]['bridge']['ports'] = []
+                for iface in split[1:]:
+                    ifaces[currif]['bridge']['ports'].append(iface)
+            elif option == "bridge_hw" and split[1].lower() == "mac":
+                ifaces[currif]['bridge']['mac'] = split[2]
+            elif option == "bridge_pathcost":
+                if 'pathcost' not in ifaces[currif]['bridge']:
+                    ifaces[currif]['bridge']['pathcost'] = {}
+                ifaces[currif]['bridge']['pathcost'][split[1]] = split[2]
+            elif option == "bridge_portprio":
+                if 'portprio' not in ifaces[currif]['bridge']:
+                    ifaces[currif]['bridge']['portprio'] = {}
+                ifaces[currif]['bridge']['portprio'][split[1]] = split[2]
+    for iface in ifaces.keys():
+        if 'auto' not in ifaces[iface]:
+            ifaces[iface]['auto'] = False
+
+
+def parse_deb_config(path):
+    """Parses a debian network configuration file."""
+    ifaces = {}
+    with open(path, "r") as fp:
+        contents = fp.read().strip()
+    parse_deb_config_data(
+        ifaces, contents,
+        os.path.dirname(os.path.abspath(path)))
+    return ifaces
+
 # vi: ts=4 expandtab syntax=python

=== added file 'tests/unittests/test_net.py'
--- tests/unittests/test_net.py	1970-01-01 00:00:00 +0000
+++ tests/unittests/test_net.py	2014-06-24 17:55:55 +0000
@@ -0,0 +1,244 @@
+from unittest import TestCase
+import os
+import shutil
+import tempfile
+
+from curtin import net
+from textwrap import dedent
+
+
+class TestNetParserData(TestCase):
+
+    def test_parse_deb_config_data_ignores_comments(self):
+        contents = dedent("""\
+            # ignore
+            # iface eth0 inet static
+            #  address 192.168.1.1
+            """)
+        ifaces = {}
+        net.parse_deb_config_data(ifaces, contents, '')
+        self.assertEqual({}, ifaces)
+
+    def test_parse_deb_config_data_basic(self):
+        contents = dedent("""\
+            iface eth0 inet static
+            address 192.168.1.2
+            netmask 255.255.255.0
+            hwaddress aa:bb:cc:dd:ee:ff
+            """)
+        ifaces = {}
+        net.parse_deb_config_data(ifaces, contents, '')
+        self.assertEqual({
+            'eth0': {
+                'auto': False,
+                'family': 'inet',
+                'method': 'static',
+                'address': '192.168.1.2',
+                'netmask': '255.255.255.0',
+                'hwaddress': 'aa:bb:cc:dd:ee:ff',
+                },
+            }, ifaces)
+
+    def test_parse_deb_config_data_auto(self):
+        contents = dedent("""\
+            auto eth0 eth1
+            iface eth0 inet manual
+            iface eth1 inet manual
+            """)
+        ifaces = {}
+        net.parse_deb_config_data(ifaces, contents, '')
+        self.assertEqual({
+            'eth0': {
+                'auto': True,
+                'family': 'inet',
+                'method': 'manual',
+                },
+            'eth1': {
+                'auto': True,
+                'family': 'inet',
+                'method': 'manual',
+                },
+            }, ifaces)
+
+    def test_parse_deb_config_data_error_on_redefine(self):
+        contents = dedent("""\
+            iface eth0 inet static
+            address 192.168.1.2
+            iface eth0 inet static
+            address 192.168.1.3
+            """)
+        ifaces = {}
+        self.assertRaises(
+            net.ParserError,
+            net.parse_deb_config_data, ifaces, contents, '')
+
+    def test_parse_deb_config_data_commands(self):
+        contents = dedent("""\
+            iface eth0 inet manual
+            pre-up preup1
+            pre-up preup2
+            up up1
+            post-up postup1
+            pre-down predown1
+            down down1
+            down down2
+            post-down postdown1
+            """)
+        ifaces = {}
+        net.parse_deb_config_data(ifaces, contents, '')
+        self.assertEqual({
+            'eth0': {
+                'auto': False,
+                'family': 'inet',
+                'method': 'manual',
+                'pre-up': ['preup1', 'preup2'],
+                'up': ['up1'],
+                'post-up': ['postup1'],
+                'pre-down': ['predown1'],
+                'down': ['down1', 'down2'],
+                'post-down': ['postdown1'],
+                },
+            }, ifaces)
+
+    def test_parse_deb_config_data_dns(self):
+        contents = dedent("""\
+            iface eth0 inet static
+            dns-nameservers 192.168.1.1 192.168.1.2
+            dns-search curtin local
+            """)
+        ifaces = {}
+        net.parse_deb_config_data(ifaces, contents, '')
+        self.assertEqual({
+            'eth0': {
+                'auto': False,
+                'family': 'inet',
+                'method': 'static',
+                'dns': {
+                    'nameservers': ['192.168.1.1', '192.168.1.2'],
+                    'search': ['curtin', 'local'],
+                    },
+                },
+            }, ifaces)
+    
+    def test_parse_deb_config_data_bridge(self):
+        contents = dedent("""\
+            iface eth0 inet manual
+            iface eth1 inet manual
+            iface br0 inet static
+            address 192.168.1.1
+            netmask 255.255.255.0
+            bridge_maxwait 30
+            bridge_ports eth0 eth1
+            bridge_pathcost eth0 1
+            bridge_pathcost eth1 2
+            bridge_portprio eth0 0
+            bridge_portprio eth1 1
+            """)
+        ifaces = {}
+        net.parse_deb_config_data(ifaces, contents, '')
+        self.assertEqual({
+            'eth0': {
+                'auto': False,
+                'family': 'inet',
+                'method': 'manual',
+                },
+            'eth1': {
+                'auto': False,
+                'family': 'inet',
+                'method': 'manual',
+                },
+            'br0': {
+                'auto': False,
+                'family': 'inet',
+                'method': 'static',
+                'address': '192.168.1.1',
+                'netmask': '255.255.255.0',
+                'bridge': {
+                    'maxwait': '30',
+                    'ports': ['eth0', 'eth1'],
+                    'pathcost': {
+                        'eth0': '1',
+                        'eth1': '2',
+                        },
+                    'portprio': {
+                        'eth0': '0',
+                        'eth1': '1'
+                        },
+                    },
+                },
+            }, ifaces)
+
+
+class TestNetParser(TestCase):
+
+    def setUp(self):
+        self.target = tempfile.mkdtemp()
+
+    def tearDown(self):
+        shutil.rmtree(self.target)
+
+    def make_config(self, path=None, name=None, contents=None,
+                    parse=True):
+        if path is None:
+            path = self.target
+        if name is None:
+            name = 'interfaces'
+        path = os.path.join(path, name)
+        if contents is None:
+            contents = dedent("""\
+                auto eth0
+                iface eth0 inet static
+                address 192.168.1.2
+                netmask 255.255.255.0
+                hwaddress aa:bb:cc:dd:ee:ff
+                """)
+        with open(path, 'w') as stream:
+            stream.write(contents)
+        ifaces = None
+        if parse:
+            ifaces = {}
+            net.parse_deb_config_data(ifaces, contents, '')
+        return path, ifaces
+
+    def test_parse_deb_config(self):
+        path, data = self.make_config()
+        expected = net.parse_deb_config(path)
+        self.assertEqual(data, expected)
+
+    def test_parse_deb_config_source(self):
+        path, data = self.make_config(name='interfaces2')
+        contents = dedent("""\
+            source interfaces2
+            iface eth1 inet manual
+            """)
+        i_path, _ = self.make_config(
+            contents=contents, parse=False)
+        data['eth1'] = {
+            'auto': False,
+            'family': 'inet',
+            'method': 'manual',
+            }
+        expected = net.parse_deb_config(i_path)
+        self.assertEqual(data, expected)
+
+    def test_parse_deb_config_source_dir(self):
+        subdir = os.path.join(self.target, 'interfaces.d')
+        os.mkdir(subdir)
+        path, data = self.make_config(
+            path=subdir, name='interfaces2')
+        contents = dedent("""\
+            source-directory interfaces.d
+            source interfaces2
+            iface eth1 inet manual
+            """)
+        i_path, _ = self.make_config(
+            contents=contents, parse=False)
+        data['eth1'] = {
+            'auto': False,
+            'family': 'inet',
+            'method': 'manual',
+            }
+        expected = net.parse_deb_config(i_path)
+        self.assertEqual(data, expected)
+
+# vi: ts=4 expandtab syntax=python