Merge ~chad.smith/cloud-init:unittests-in-cloudinit-package into cloud-init:master

[Chad Smith]

cloudinit.net: add initialize_network_device function and tests

This is not yet called, but will be called in a subsequent Ec2-related branch to manually initialize a network interface with the responses using dhcp discovery without any dhcp-script side-effects. The functionality has been tested on Ec2 ubuntu and CentOS vms to ensure that network interface initialization works in both OS-types.

Since there was poor unit test coverage for the cloudinit.net.__init__ module, this branch adds a bunch of coverage to the functions in cloudinit.net.__init. We can also now have unit tests local to the cloudinit modules. The benefits of having unittests under cloudinit module:
 - Proximity of unittest to cloudinit module makes it easier for ongoing devs to know where to augment unit tests. The tests.unittest directory is organizated such that it
 - Allows for 1 to 1 name mapping module -> tests/test_module.py
 - Improved test and module isolation, if we find unit tests have to import from a number of modules besides the module under test, it will better prompt resturcturing of the module.

This also branch touches:
 - tox.ini to run unit tests found in cloudinit as well as include all test-requirements for pylint since we now have unit tests living within cloudinit package
 - setup.py to exclude any test modules under cloudinit when packaging

cloudinit.net: add initialize_network_device function and unittest.

This is not yet called, but will be called in a subsequent Ec2-related branch to manually initialize a network interface with the responses using dhcp discovery without any dhcp-script side-effects. The functionality has been tested on Ec2 ubuntu and CentOS vms to ensure that network interface initialization works in both OS-types.

Since there was poor unit test coverage for the cloudinit.net.__init__ module, this branch adds a bunch of coverage to the functions in cloudinit.net.__init. We can also now have unit tests local to the cloudinit modules. The benefits of having unittests under cloudinit module:
 - Proximity of unittest to cloudinit module makes it easier for ongoing devs to know where to augment unit tests. The tests.unittest directory is organizated such that it
 - Allows for 1 to 1 name mapping module -> tests/test_module.py
 - Improved test and module isolation, if we find unit tests have to import from a number of modules besides the module under test, it will better prompt resturcturing of the module.

This also branch touches:
 - tox.ini to run unit tests found in cloudinit as well as include mock test-requirement for pylint since we now have unit tests living within cloudinit package
 - setup.py to exclude any test modules under cloudinit when packaging

To test:
   make deb
   dpkg -c cloud-init_all.deb | grep test # make sure our package didn't include tests
   tox
   # on an lxc: ifconfig eth0 0.0.0.0; python -c 'from cloudinit.net import initialize_network_device; initialize_network_device("eth0", "ip-addr", "netmask", "broadcast")'

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:a3692fcda19267d6d63b0317cdfb40d6df8b08ed
https://jenkins.ubuntu.com/server/job/cloud-init-ci/64/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    SUCCESS: CentOS 6 & 7: Build & Test
    IN_PROGRESS: Declarative: Post Actions

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review: Approve (continuous-integration)

[Scott Moser (smoser)]

why did you have to add mock to tox's pylint entries ?
also some inline.
this does look really nice though.
thank you.

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:ed950d276972c869bbeb87dead0cc4ba55e2fc88
https://jenkins.ubuntu.com/server/job/cloud-init-ci/83/
Executed test runs:
    SUCCESS: Checkout
    FAILED: Unit & Style Tests

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review: Needs Fixing (continuous-integration)

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:4b4989d894331e07041c2656ec7f02e6ed68b140
https://jenkins.ubuntu.com/server/job/cloud-init-ci/84/
Executed test runs:
    SUCCESS: Checkout
    FAILED: Unit & Style Tests

Click here to trigger a rebuild:
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review: Needs Fixing (continuous-integration)

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:a3692fcda19267d6d63b0317cdfb40d6df8b08ed
https://jenkins.ubuntu.com/server/job/cloud-init-ci/85/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    SUCCESS: CentOS 6 & 7: Build & Test
    IN_PROGRESS: Declarative: Post Actions

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review: Approve (continuous-integration)

0f476ef... by Chad Smith on 2017-07-22

For realsies: it makes more sense that EphemeralIPv4Network is a context manager than DhcpCleanDiscovery handling all the setup an teardown of ips. Also allow EphemeralIPv4Network to accept prefix or netmask

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:0f476ef54a97487dc913027f6be3a071aaeb9575
https://jenkins.ubuntu.com/server/job/cloud-init-ci/86/
Executed test runs:
    SUCCESS: Checkout
    FAILED: Unit & Style Tests

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review: Needs Fixing (continuous-integration)

4811785... by Chad Smith on 2017-07-24

mock get_sys_class_path function in unit tests to allow for cleanup

a0bd7a7... by Chad Smith on 2017-07-24

lints

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:a0bd7a79f0869fc3bb09272cb030f84f1bb335f1
https://jenkins.ubuntu.com/server/job/cloud-init-ci/87/
Executed test runs:
    SUCCESS: Checkout
    FAILED: Unit & Style Tests

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review: Needs Fixing (continuous-integration)

e37c259... by Chad Smith on 2017-07-24

check is_up instead of is_connected before configuring a device

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:e37c259841bc6d902e9fec9c4a5dc1db3ebac70f
https://jenkins.ubuntu.com/server/job/cloud-init-ci/89/
Executed test runs:
    SUCCESS: Checkout
    FAILED: Unit & Style Tests

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review: Needs Fixing (continuous-integration)

93ace28... by Chad Smith on 2017-07-25

fixup leaky unittest mocks

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:93ace2828ef808bf32208e325de125ab40e4cefd
https://jenkins.ubuntu.com/server/job/cloud-init-ci/91/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    FAILED: CentOS 6 & 7: Build & Test

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review: Needs Fixing (continuous-integration)

[Scott Moser (smoser)]

small questions in line.

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:93ace2828ef808bf32208e325de125ab40e4cefd
https://jenkins.ubuntu.com/server/job/cloud-init-ci/92/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    SUCCESS: CentOS 6 & 7: Build & Test
    IN_PROGRESS: Declarative: Post Actions

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review: Approve (continuous-integration)

b6369bd... by Chad Smith on 2017-07-26

add get_ip_info helper function to allow inspecting ip addrs before setup or teardown in EphemeralIPv4Network context manager.

787586e... by Chad Smith on 2017-07-26

add exception handling if ip command or specified interface does not exist. Add unit tests for setup and teardown ip commands

cdba67c... by Chad Smith on 2017-07-26

add cleanup to remove ip addr from device during exit of EphemeralIPv4Network context manager

[Server Team CI bot (server-team-bot)]

FAILED: Continuous integration, rev:787586e45a5860c9be2ac13847b61855e29f7623
https://jenkins.ubuntu.com/server/job/cloud-init-ci/100/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    FAILED: Ubuntu LTS: Build

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review: Needs Fixing (continuous-integration)

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:cdba67c453c1da7b80d8d07274bc2d1c4995cb43
https://jenkins.ubuntu.com/server/job/cloud-init-ci/101/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    SUCCESS: CentOS 6 & 7: Build & Test
    IN_PROGRESS: Declarative: Post Actions

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review: Approve (continuous-integration)

c25b725... by Chad Smith on 2017-07-27

drop get_ip_info utility function and handle ProcessExecutionError mentioning File Exists when addr is already set

9cdbb64... by Chad Smith on 2017-07-27

lints/flakes

8ef6575... by Chad Smith on 2017-07-27

include all unit test-requirements for tox lint targets

[Chad Smith (chad.smith)]

Per our discussion today, I simplified logic in EphemeralIPv4Network context manager to first attempt to add a network address and handle a non-zero exit code if the address already exits.

All changes have been made per review comments, I separated out get_ip_info utility function so we can propose it as a separate branch to replace ifconfig parsing.

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:8ef6575c63eb4aaf08f1b0091d96cf1b8c9819e6
https://jenkins.ubuntu.com/server/job/cloud-init-ci/102/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    SUCCESS: CentOS 6 & 7: Build & Test
    IN_PROGRESS: Declarative: Post Actions

Click here to trigger a rebuild:
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review: Approve (continuous-integration)

3d85180... by Chad Smith on 2017-07-27

route del needs to happen before ip addr del

[Chad Smith (chad.smith)]

Just tested on ubuntu AWS. minor fix needed to remove the route before removing the address, because the side-effect of removing the addr is the route is auto-deleted.

[Chad Smith (chad.smith)]

Just validated on cent6 too:
2017-07-27 21:33:19,762 - handlers.py[DEBUG]: finish: init-local/search-Ec2Local: SUCCESS: found local data from DataSourceEc2Local

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:3d851806873f3f050cbe29206ab32c5fe7fa5cc9
https://jenkins.ubuntu.com/server/job/cloud-init-ci/103/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    SUCCESS: CentOS 6 & 7: Build & Test
    IN_PROGRESS: Declarative: Post Actions

Click here to trigger a rebuild:
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review: Approve (continuous-integration)

[Scott Moser (smoser)]

tiny things.
fix that comment, and i approve.
thank you Chad.

review: Approve

49a4b83... by Chad Smith on 2017-07-28

docstring fixup

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:49a4b8327125b4e5105c8508c08cc333480ff7e1
https://jenkins.ubuntu.com/server/job/cloud-init-ci/104/
Executed test runs:
    SUCCESS: Checkout
    SUCCESS: Unit & Style Tests
    SUCCESS: Ubuntu LTS: Build
    SUCCESS: Ubuntu LTS: Integration
    SUCCESS: CentOS 6 & 7: Build & Test
    IN_PROGRESS: Declarative: Post Actions

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review: Approve (continuous-integration)

diff --git a/cloudinit/net/__init__.py b/cloudinit/net/__init__.py
index d1740e5..46cb9c8 100644
--- a/cloudinit/net/__init__.py
+++ b/cloudinit/net/__init__.py
@@ -10,6 +10,7 @@ import logging
 import os
 import re
 
+from cloudinit.net.network_state import mask_to_net_prefix
 from cloudinit import util
 
 LOG = logging.getLogger(__name__)
@@ -28,8 +29,13 @@ def _natural_sort_key(s, _nsre=re.compile('([0-9]+)')):
             for text in re.split(_nsre, s)]
 
 
+def get_sys_class_path():
+    """Simple function to return the global SYS_CLASS_NET."""
+    return SYS_CLASS_NET
+
+
 def sys_dev_path(devname, path=""):
-    return SYS_CLASS_NET + devname + "/" + path
+    return get_sys_class_path() + devname + "/" + path
 
 
 def read_sys_net(devname, path, translate=None,
@@ -77,7 +83,7 @@ def read_sys_net_int(iface, field):
         return None
     try:
         return int(val)
-    except TypeError:
+    except ValueError:
         return None
 
 
@@ -149,7 +155,14 @@ def device_devid(devname):
 
 
 def get_devicelist():
-    return os.listdir(SYS_CLASS_NET)
+    try:
+        devs = os.listdir(get_sys_class_path())
+    except OSError as e:
+        if e.errno == errno.ENOENT:
+            devs = []
+        else:
+            raise
+    return devs
 
 
 class ParserError(Exception):
@@ -497,14 +510,8 @@ def get_interfaces_by_mac():
     """Build a dictionary of tuples {mac: name}.
 
     Bridges and any devices that have a 'stolen' mac are excluded."""
-    try:
-        devs = get_devicelist()
-    except OSError as e:
-        if e.errno == errno.ENOENT:
-            devs = []
-        else:
-            raise
     ret = {}
+    devs = get_devicelist()
     empty_mac = '00:00:00:00:00:00'
     for name in devs:
         if not interface_has_own_mac(name):
@@ -531,14 +538,8 @@ def get_interfaces():
     """Return list of interface tuples (name, mac, driver, device_id)
 
     Bridges and any devices that have a 'stolen' mac are excluded."""
-    try:
-        devs = get_devicelist()
-    except OSError as e:
-        if e.errno == errno.ENOENT:
-            devs = []
-        else:
-            raise
     ret = []
+    devs = get_devicelist()
     empty_mac = '00:00:00:00:00:00'
     for name in devs:
         if not interface_has_own_mac(name):
@@ -557,6 +558,102 @@ def get_interfaces():
     return ret
 
 
+class EphemeralIPv4Network(object):
+    """Context manager which sets up temporary static network configuration.
+
+    No operations are performed if the provided interface is already connected.
+    If unconnected, bring up the interface with valid ip, prefix and broadcast.
+    If router is provided setup a default route for that interface. Upon
+    context exit, clean up the interface leaving no configuration behind.
+    """
+
+    def __init__(self, interface, ip, prefix_or_mask, broadcast, router=None):
+        """Setup context manager and validate call signature.
+
+        @param interface: Name of the network interface to bring up.
+        @param ip: IP address to assign to the interface.
+        @param prefix_or_mask: Either netmask of the format X.X.X.X or an int
+            prefix.
+        @param broadcast: Broadcast address for the IPv4 network.
+        @param router: Optionally the default gateway IP.
+        """
+        if not all([interface, ip, prefix_or_mask, broadcast]):
+            raise ValueError(
+                'Cannot init network on {0} with {1}/{2} and bcast {3}'.format(
+                    interface, ip, prefix_or_mask, broadcast))
+        try:
+            self.prefix = mask_to_net_prefix(prefix_or_mask)
+        except ValueError as e:
+            raise ValueError(
+                'Cannot setup network: {0}'.format(e))
+        self.interface = interface
+        self.ip = ip
+        self.broadcast = broadcast
+        self.router = router
+        self.cleanup_cmds = []  # List of commands to run to cleanup state.
+
+    def __enter__(self):
+        """Perform ephemeral network setup if interface is not connected."""
+        self._bringup_device()
+        if self.router:
+            self._bringup_router()
+
+    def __exit__(self, excp_type, excp_value, excp_traceback):
+        for cmd in self.cleanup_cmds:
+            util.subp(cmd, capture=True)
+
+    def _delete_address(self, address, prefix):
+        """Perform the ip command to remove the specified address."""
+        util.subp(
+            ['ip', '-family', 'inet', 'addr', 'del',
+             '%s/%s' % (address, prefix), 'dev', self.interface],
+            capture=True)
+
+    def _bringup_device(self):
+        """Perform the ip comands to fully setup the device."""
+        cidr = '{0}/{1}'.format(self.ip, self.prefix)
+        LOG.debug(
+            'Attempting setup of ephemeral network on %s with %s brd %s',
+            self.interface, cidr, self.broadcast)
+        try:
+            util.subp(
+                ['ip', '-family', 'inet', 'addr', 'add', cidr, 'broadcast',
+                 self.broadcast, 'dev', self.interface],
+                capture=True, update_env={'LANG': 'C'})
+        except util.ProcessExecutionError as e:
+            if "File exists" not in e.stderr:
+                raise
+            LOG.debug(
+                'Skip ephemeral network setup, %s already has address %s',
+                self.interface, self.ip)
+        else:
+            # Address creation success, bring up device and queue cleanup
+            util.subp(
+                ['ip', '-family', 'inet', 'link', 'set', 'dev', self.interface,
+                 'up'], capture=True)
+            self.cleanup_cmds.append(
+                ['ip', '-family', 'inet', 'link', 'set', 'dev', self.interface,
+                 'down'])
+            self.cleanup_cmds.append(
+                ['ip', '-family', 'inet', 'addr', 'del', cidr, 'dev',
+                 self.interface])
+
+    def _bringup_router(self):
+        """Perform the ip commands to fully setup the router if needed."""
+        # Check if a default route exists and exit if it does
+        out, _ = util.subp(['ip', 'route', 'show', '0.0.0.0/0'], capture=True)
+        if 'default' in out:
+            LOG.debug(
+                'Skip ephemeral route setup. %s already has default route: %s',
+                self.interface, out.strip())
+            return
+        util.subp(
+            ['ip', '-4', 'route', 'add', 'default', 'via', self.router,
+             'dev', self.interface], capture=True)
+        self.cleanup_cmds.insert(
+            0, ['ip', '-4', 'route', 'del', 'default', 'dev', self.interface])
+
+
 class RendererNotFoundError(RuntimeError):
     pass
 
diff --git a/cloudinit/net/tests/__init__.py b/cloudinit/net/tests/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/cloudinit/net/tests/__init__.py
diff --git a/cloudinit/net/tests/test_init.py b/cloudinit/net/tests/test_init.py
new file mode 100644
index 0000000..272a6eb
--- /dev/null
+++ b/cloudinit/net/tests/test_init.py
@@ -0,0 +1,522 @@
+# This file is part of cloud-init. See LICENSE file for license information.
+
+import copy
+import errno
+import mock
+import os
+
+import cloudinit.net as net
+from cloudinit.util import ensure_file, write_file, ProcessExecutionError
+from tests.unittests.helpers import CiTestCase
+
+
+class TestSysDevPath(CiTestCase):
+
+    def test_sys_dev_path(self):
+        """sys_dev_path returns a path under SYS_CLASS_NET for a device."""
+        dev = 'something'
+        path = 'attribute'
+        expected = net.SYS_CLASS_NET + dev + '/' + path
+        self.assertEqual(expected, net.sys_dev_path(dev, path))
+
+    def test_sys_dev_path_without_path(self):
+        """When path param isn't provided it defaults to empty string."""
+        dev = 'something'
+        expected = net.SYS_CLASS_NET + dev + '/'
+        self.assertEqual(expected, net.sys_dev_path(dev))
+
+
+class TestReadSysNet(CiTestCase):
+    with_logs = True
+
+    def setUp(self):
+        super(TestReadSysNet, self).setUp()
+        sys_mock = mock.patch('cloudinit.net.get_sys_class_path')
+        self.m_sys_path = sys_mock.start()
+        self.sysdir = self.tmp_dir() + '/'
+        self.m_sys_path.return_value = self.sysdir
+        self.addCleanup(sys_mock.stop)
+
+    def test_read_sys_net_strips_contents_of_sys_path(self):
+        """read_sys_net strips whitespace from the contents of a sys file."""
+        content = 'some stuff with trailing whitespace\t\r\n'
+        write_file(os.path.join(self.sysdir, 'dev', 'attr'), content)
+        self.assertEqual(content.strip(), net.read_sys_net('dev', 'attr'))
+
+    def test_read_sys_net_reraises_oserror(self):
+        """read_sys_net raises OSError/IOError when file doesn't exist."""
+        # Non-specific Exception because versions of python OSError vs IOError.
+        with self.assertRaises(Exception) as context_manager:  # noqa: H202
+            net.read_sys_net('dev', 'attr')
+        error = context_manager.exception
+        self.assertIn('No such file or directory', str(error))
+
+    def test_read_sys_net_handles_error_with_on_enoent(self):
+        """read_sys_net handles OSError/IOError with on_enoent if provided."""
+        handled_errors = []
+
+        def on_enoent(e):
+            handled_errors.append(e)
+
+        net.read_sys_net('dev', 'attr', on_enoent=on_enoent)
+        error = handled_errors[0]
+        self.assertIsInstance(error, Exception)
+        self.assertIn('No such file or directory', str(error))
+
+    def test_read_sys_net_translates_content(self):
+        """read_sys_net translates content when translate dict is provided."""
+        content = "you're welcome\n"
+        write_file(os.path.join(self.sysdir, 'dev', 'attr'), content)
+        translate = {"you're welcome": 'de nada'}
+        self.assertEqual(
+            'de nada',
+            net.read_sys_net('dev', 'attr', translate=translate))
+
+    def test_read_sys_net_errors_on_translation_failures(self):
+        """read_sys_net raises a KeyError and logs details on failure."""
+        content = "you're welcome\n"
+        write_file(os.path.join(self.sysdir, 'dev', 'attr'), content)
+        with self.assertRaises(KeyError) as context_manager:
+            net.read_sys_net('dev', 'attr', translate={})
+        error = context_manager.exception
+        self.assertEqual('"you\'re welcome"', str(error))
+        self.assertIn(
+            "Found unexpected (not translatable) value 'you're welcome' in "
+            "'{0}dev/attr".format(self.sysdir),
+            self.logs.getvalue())
+
+    def test_read_sys_net_handles_handles_with_onkeyerror(self):
+        """read_sys_net handles translation errors calling on_keyerror."""
+        content = "you're welcome\n"
+        write_file(os.path.join(self.sysdir, 'dev', 'attr'), content)
+        handled_errors = []
+
+        def on_keyerror(e):
+            handled_errors.append(e)
+
+        net.read_sys_net('dev', 'attr', translate={}, on_keyerror=on_keyerror)
+        error = handled_errors[0]
+        self.assertIsInstance(error, KeyError)
+        self.assertEqual('"you\'re welcome"', str(error))
+
+    def test_read_sys_net_safe_false_on_translate_failure(self):
+        """read_sys_net_safe returns False on translation failures."""
+        content = "you're welcome\n"
+        write_file(os.path.join(self.sysdir, 'dev', 'attr'), content)
+        self.assertFalse(net.read_sys_net_safe('dev', 'attr', translate={}))
+
+    def test_read_sys_net_safe_returns_false_on_noent_failure(self):
+        """read_sys_net_safe returns False on file not found failures."""
+        self.assertFalse(net.read_sys_net_safe('dev', 'attr'))
+
+    def test_read_sys_net_int_returns_none_on_error(self):
+        """read_sys_net_safe returns None on failures."""
+        self.assertFalse(net.read_sys_net_int('dev', 'attr'))
+
+    def test_read_sys_net_int_returns_none_on_valueerror(self):
+        """read_sys_net_safe returns None when content is not an int."""
+        write_file(os.path.join(self.sysdir, 'dev', 'attr'), 'NOTINT\n')
+        self.assertFalse(net.read_sys_net_int('dev', 'attr'))
+
+    def test_read_sys_net_int_returns_integer_from_content(self):
+        """read_sys_net_safe returns None on failures."""
+        write_file(os.path.join(self.sysdir, 'dev', 'attr'), '1\n')
+        self.assertEqual(1, net.read_sys_net_int('dev', 'attr'))
+
+    def test_is_up_true(self):
+        """is_up is True if sys/net/devname/operstate is 'up' or 'unknown'."""
+        for state in ['up', 'unknown']:
+            write_file(os.path.join(self.sysdir, 'eth0', 'operstate'), state)
+            self.assertTrue(net.is_up('eth0'))
+
+    def test_is_up_false(self):
+        """is_up is False if sys/net/devname/operstate is 'down' or invalid."""
+        for state in ['down', 'incomprehensible']:
+            write_file(os.path.join(self.sysdir, 'eth0', 'operstate'), state)
+            self.assertFalse(net.is_up('eth0'))
+
+    def test_is_wireless(self):
+        """is_wireless is True when /sys/net/devname/wireless exists."""
+        self.assertFalse(net.is_wireless('eth0'))
+        ensure_file(os.path.join(self.sysdir, 'eth0', 'wireless'))
+        self.assertTrue(net.is_wireless('eth0'))
+
+    def test_is_bridge(self):
+        """is_bridge is True when /sys/net/devname/bridge exists."""
+        self.assertFalse(net.is_bridge('eth0'))
+        ensure_file(os.path.join(self.sysdir, 'eth0', 'bridge'))
+        self.assertTrue(net.is_bridge('eth0'))
+
+    def test_is_bond(self):
+        """is_bond is True when /sys/net/devname/bonding exists."""
+        self.assertFalse(net.is_bond('eth0'))
+        ensure_file(os.path.join(self.sysdir, 'eth0', 'bonding'))
+        self.assertTrue(net.is_bond('eth0'))
+
+    def test_is_vlan(self):
+        """is_vlan is True when /sys/net/devname/uevent has DEVTYPE=vlan."""
+        ensure_file(os.path.join(self.sysdir, 'eth0', 'uevent'))
+        self.assertFalse(net.is_vlan('eth0'))
+        content = 'junk\nDEVTYPE=vlan\njunk\n'
+        write_file(os.path.join(self.sysdir, 'eth0', 'uevent'), content)
+        self.assertTrue(net.is_vlan('eth0'))
+
+    def test_is_connected_when_physically_connected(self):
+        """is_connected is True when /sys/net/devname/iflink reports 2."""
+        self.assertFalse(net.is_connected('eth0'))
+        write_file(os.path.join(self.sysdir, 'eth0', 'iflink'), "2")
+        self.assertTrue(net.is_connected('eth0'))
+
+    def test_is_connected_when_wireless_and_carrier_active(self):
+        """is_connected is True if wireless /sys/net/devname/carrier is 1."""
+        self.assertFalse(net.is_connected('eth0'))
+        ensure_file(os.path.join(self.sysdir, 'eth0', 'wireless'))
+        self.assertFalse(net.is_connected('eth0'))
+        write_file(os.path.join(self.sysdir, 'eth0', 'carrier'), "1")
+        self.assertTrue(net.is_connected('eth0'))
+
+    def test_is_physical(self):
+        """is_physical is True when /sys/net/devname/device exists."""
+        self.assertFalse(net.is_physical('eth0'))
+        ensure_file(os.path.join(self.sysdir, 'eth0', 'device'))
+        self.assertTrue(net.is_physical('eth0'))
+
+    def test_is_present(self):
+        """is_present is True when /sys/net/devname exists."""
+        self.assertFalse(net.is_present('eth0'))
+        ensure_file(os.path.join(self.sysdir, 'eth0', 'device'))
+        self.assertTrue(net.is_present('eth0'))
+
+
+class TestGenerateFallbackConfig(CiTestCase):
+
+    def setUp(self):
+        super(TestGenerateFallbackConfig, self).setUp()
+        sys_mock = mock.patch('cloudinit.net.get_sys_class_path')
+        self.m_sys_path = sys_mock.start()
+        self.sysdir = self.tmp_dir() + '/'
+        self.m_sys_path.return_value = self.sysdir
+        self.addCleanup(sys_mock.stop)
+
+    def test_generate_fallback_finds_connected_eth_with_mac(self):
+        """generate_fallback_config finds any connected device with a mac."""
+        write_file(os.path.join(self.sysdir, 'eth0', 'carrier'), '1')
+        write_file(os.path.join(self.sysdir, 'eth1', 'carrier'), '1')
+        mac = 'aa:bb:cc:aa:bb:cc'
+        write_file(os.path.join(self.sysdir, 'eth1', 'address'), mac)
+        expected = {
+            'config': [{'type': 'physical', 'mac_address': mac,
+                        'name': 'eth1', 'subnets': [{'type': 'dhcp'}]}],
+            'version': 1}
+        self.assertEqual(expected, net.generate_fallback_config())
+
+    def test_generate_fallback_finds_dormant_eth_with_mac(self):
+        """generate_fallback_config finds any dormant device with a mac."""
+        write_file(os.path.join(self.sysdir, 'eth0', 'dormant'), '1')
+        mac = 'aa:bb:cc:aa:bb:cc'
+        write_file(os.path.join(self.sysdir, 'eth0', 'address'), mac)
+        expected = {
+            'config': [{'type': 'physical', 'mac_address': mac,
+                        'name': 'eth0', 'subnets': [{'type': 'dhcp'}]}],
+            'version': 1}
+        self.assertEqual(expected, net.generate_fallback_config())
+
+    def test_generate_fallback_finds_eth_by_operstate(self):
+        """generate_fallback_config finds any dormant device with a mac."""
+        mac = 'aa:bb:cc:aa:bb:cc'
+        write_file(os.path.join(self.sysdir, 'eth0', 'address'), mac)
+        expected = {
+            'config': [{'type': 'physical', 'mac_address': mac,
+                        'name': 'eth0', 'subnets': [{'type': 'dhcp'}]}],
+            'version': 1}
+        valid_operstates = ['dormant', 'down', 'lowerlayerdown', 'unknown']
+        for state in valid_operstates:
+            write_file(os.path.join(self.sysdir, 'eth0', 'operstate'), state)
+            self.assertEqual(expected, net.generate_fallback_config())
+        write_file(os.path.join(self.sysdir, 'eth0', 'operstate'), 'noworky')
+        self.assertIsNone(net.generate_fallback_config())
+
+    def test_generate_fallback_config_skips_veth(self):
+        """generate_fallback_config will skip any veth interfaces."""
+        # A connected veth which gets ignored
+        write_file(os.path.join(self.sysdir, 'veth0', 'carrier'), '1')
+        self.assertIsNone(net.generate_fallback_config())
+
+    def test_generate_fallback_config_skips_bridges(self):
+        """generate_fallback_config will skip any bridges interfaces."""
+        # A connected veth which gets ignored
+        write_file(os.path.join(self.sysdir, 'eth0', 'carrier'), '1')
+        mac = 'aa:bb:cc:aa:bb:cc'
+        write_file(os.path.join(self.sysdir, 'eth0', 'address'), mac)
+        ensure_file(os.path.join(self.sysdir, 'eth0', 'bridge'))
+        self.assertIsNone(net.generate_fallback_config())
+
+    def test_generate_fallback_config_skips_bonds(self):
+        """generate_fallback_config will skip any bonded interfaces."""
+        # A connected veth which gets ignored
+        write_file(os.path.join(self.sysdir, 'eth0', 'carrier'), '1')
+        mac = 'aa:bb:cc:aa:bb:cc'
+        write_file(os.path.join(self.sysdir, 'eth0', 'address'), mac)
+        ensure_file(os.path.join(self.sysdir, 'eth0', 'bonding'))
+        self.assertIsNone(net.generate_fallback_config())
+
+
+class TestGetDeviceList(CiTestCase):
+
+    def setUp(self):
+        super(TestGetDeviceList, self).setUp()
+        sys_mock = mock.patch('cloudinit.net.get_sys_class_path')
+        self.m_sys_path = sys_mock.start()
+        self.sysdir = self.tmp_dir() + '/'
+        self.m_sys_path.return_value = self.sysdir
+        self.addCleanup(sys_mock.stop)
+
+    def test_get_devicelist_raise_oserror(self):
+        """get_devicelist raise any non-ENOENT OSerror."""
+        error = OSError('Can not do it')
+        error.errno = errno.EPERM  # Set non-ENOENT
+        self.m_sys_path.side_effect = error
+        with self.assertRaises(OSError) as context_manager:
+            net.get_devicelist()
+        exception = context_manager.exception
+        self.assertEqual('Can not do it', str(exception))
+
+    def test_get_devicelist_empty_without_sys_net(self):
+        """get_devicelist returns empty list when missing SYS_CLASS_NET."""
+        self.m_sys_path.return_value = 'idontexist'
+        self.assertEqual([], net.get_devicelist())
+
+    def test_get_devicelist_empty_with_no_devices_in_sys_net(self):
+        """get_devicelist returns empty directoty listing for SYS_CLASS_NET."""
+        self.assertEqual([], net.get_devicelist())
+
+    def test_get_devicelist_lists_any_subdirectories_in_sys_net(self):
+        """get_devicelist returns a directory listing for SYS_CLASS_NET."""
+        write_file(os.path.join(self.sysdir, 'eth0', 'operstate'), 'up')
+        write_file(os.path.join(self.sysdir, 'eth1', 'operstate'), 'up')
+        self.assertItemsEqual(['eth0', 'eth1'], net.get_devicelist())
+
+
+class TestGetInterfaceMAC(CiTestCase):
+
+    def setUp(self):
+        super(TestGetInterfaceMAC, self).setUp()
+        sys_mock = mock.patch('cloudinit.net.get_sys_class_path')
+        self.m_sys_path = sys_mock.start()
+        self.sysdir = self.tmp_dir() + '/'
+        self.m_sys_path.return_value = self.sysdir
+        self.addCleanup(sys_mock.stop)
+
+    def test_get_interface_mac_false_with_no_mac(self):
+        """get_device_list returns False when no mac is reported."""
+        ensure_file(os.path.join(self.sysdir, 'eth0', 'bonding'))
+        mac_path = os.path.join(self.sysdir, 'eth0', 'address')
+        self.assertFalse(os.path.exists(mac_path))
+        self.assertFalse(net.get_interface_mac('eth0'))
+
+    def test_get_interface_mac(self):
+        """get_interfaces returns the mac from SYS_CLASS_NET/dev/address."""
+        mac = 'aa:bb:cc:aa:bb:cc'
+        write_file(os.path.join(self.sysdir, 'eth1', 'address'), mac)
+        self.assertEqual(mac, net.get_interface_mac('eth1'))
+
+    def test_get_interface_mac_grabs_bonding_address(self):
+        """get_interfaces returns the source device mac for bonded devices."""
+        source_dev_mac = 'aa:bb:cc:aa:bb:cc'
+        bonded_mac = 'dd:ee:ff:dd:ee:ff'
+        write_file(os.path.join(self.sysdir, 'eth1', 'address'), bonded_mac)
+        write_file(
+            os.path.join(self.sysdir, 'eth1', 'bonding_slave', 'perm_hwaddr'),
+            source_dev_mac)
+        self.assertEqual(source_dev_mac, net.get_interface_mac('eth1'))
+
+    def test_get_interfaces_empty_list_without_sys_net(self):
+        """get_interfaces returns an empty list when missing SYS_CLASS_NET."""
+        self.m_sys_path.return_value = 'idontexist'
+        self.assertEqual([], net.get_interfaces())
+
+    def test_get_interfaces_by_mac_skips_empty_mac(self):
+        """Ignore 00:00:00:00:00:00 addresses from get_interfaces_by_mac."""
+        empty_mac = '00:00:00:00:00:00'
+        mac = 'aa:bb:cc:aa:bb:cc'
+        write_file(os.path.join(self.sysdir, 'eth1', 'address'), empty_mac)
+        write_file(os.path.join(self.sysdir, 'eth1', 'addr_assign_type'), '0')
+        write_file(os.path.join(self.sysdir, 'eth2', 'addr_assign_type'), '0')
+        write_file(os.path.join(self.sysdir, 'eth2', 'address'), mac)
+        expected = [('eth2', 'aa:bb:cc:aa:bb:cc', None, None)]
+        self.assertEqual(expected, net.get_interfaces())
+
+    def test_get_interfaces_by_mac_skips_missing_mac(self):
+        """Ignore interfaces without an address from get_interfaces_by_mac."""
+        write_file(os.path.join(self.sysdir, 'eth1', 'addr_assign_type'), '0')
+        address_path = os.path.join(self.sysdir, 'eth1', 'address')
+        self.assertFalse(os.path.exists(address_path))
+        mac = 'aa:bb:cc:aa:bb:cc'
+        write_file(os.path.join(self.sysdir, 'eth2', 'addr_assign_type'), '0')
+        write_file(os.path.join(self.sysdir, 'eth2', 'address'), mac)
+        expected = [('eth2', 'aa:bb:cc:aa:bb:cc', None, None)]
+        self.assertEqual(expected, net.get_interfaces())
+
+
+class TestInterfaceHasOwnMAC(CiTestCase):
+
+    def setUp(self):
+        super(TestInterfaceHasOwnMAC, self).setUp()
+        sys_mock = mock.patch('cloudinit.net.get_sys_class_path')
+        self.m_sys_path = sys_mock.start()
+        self.sysdir = self.tmp_dir() + '/'
+        self.m_sys_path.return_value = self.sysdir
+        self.addCleanup(sys_mock.stop)
+
+    def test_interface_has_own_mac_false_when_stolen(self):
+        """Return False from interface_has_own_mac when address is stolen."""
+        write_file(os.path.join(self.sysdir, 'eth1', 'addr_assign_type'), '2')
+        self.assertFalse(net.interface_has_own_mac('eth1'))
+
+    def test_interface_has_own_mac_true_when_not_stolen(self):
+        """Return False from interface_has_own_mac when mac isn't stolen."""
+        valid_assign_types = ['0', '1', '3']
+        assign_path = os.path.join(self.sysdir, 'eth1', 'addr_assign_type')
+        for _type in valid_assign_types:
+            write_file(assign_path, _type)
+            self.assertTrue(net.interface_has_own_mac('eth1'))
+
+    def test_interface_has_own_mac_strict_errors_on_absent_assign_type(self):
+        """When addr_assign_type is absent, interface_has_own_mac errors."""
+        with self.assertRaises(ValueError):
+            net.interface_has_own_mac('eth1', strict=True)
+
+
[e-mail]('cloudinit.net.util.subp')
+class TestEphemeralIPV4Network(CiTestCase):
+
+    with_logs = True
+
+    def setUp(self):
+        super(TestEphemeralIPV4Network, self).setUp()
+        sys_mock = mock.patch('cloudinit.net.get_sys_class_path')
+        self.m_sys_path = sys_mock.start()
+        self.sysdir = self.tmp_dir() + '/'
+        self.m_sys_path.return_value = self.sysdir
+        self.addCleanup(sys_mock.stop)
+
+    def test_ephemeral_ipv4_network_errors_on_missing_params(self, m_subp):
+        """No required params for EphemeralIPv4Network can be None."""
+        required_params = {
+            'interface': 'eth0', 'ip': '192.168.2.2',
+            'prefix_or_mask': '255.255.255.0', 'broadcast': '192.168.2.255'}
+        for key in required_params.keys():
+            params = copy.deepcopy(required_params)
+            params[key] = None
+            with self.assertRaises(ValueError) as context_manager:
+                net.EphemeralIPv4Network(**params)
+            error = context_manager.exception
+            self.assertIn('Cannot init network on', str(error))
+            self.assertEqual(0, m_subp.call_count)
+
+    def test_ephemeral_ipv4_network_errors_invalid_mask(self, m_subp):
+        """Raise an error when prefix_or_mask is not a netmask or prefix."""
+        params = {
+            'interface': 'eth0', 'ip': '192.168.2.2',
+            'broadcast': '192.168.2.255'}
+        invalid_masks = ('invalid', 'invalid.', '123.123.123')
+        for error_val in invalid_masks:
+            params['prefix_or_mask'] = error_val
+            with self.assertRaises(ValueError) as context_manager:
+                with net.EphemeralIPv4Network(**params):
+                    pass
+            error = context_manager.exception
+            self.assertIn('Cannot setup network: netmask', str(error))
+            self.assertEqual(0, m_subp.call_count)
+
+    def test_ephemeral_ipv4_network_performs_teardown(self, m_subp):
+        """EphemeralIPv4Network performs teardown on the device if setup."""
+        expected_setup_calls = [
+            mock.call(
+                ['ip', '-family', 'inet', 'addr', 'add', '192.168.2.2/24',
+                 'broadcast', '192.168.2.255', 'dev', 'eth0'],
+                capture=True, update_env={'LANG': 'C'}),
+            mock.call(
+                ['ip', '-family', 'inet', 'link', 'set', 'dev', 'eth0', 'up'],
+                capture=True)]
+        expected_teardown_calls = [
+            mock.call(
+                ['ip', '-family', 'inet', 'link', 'set', 'dev', 'eth0',
+                 'down'], capture=True),
+            mock.call(
+                ['ip', '-family', 'inet', 'addr', 'del', '192.168.2.2/24',
+                 'dev', 'eth0'], capture=True)]
+        params = {
+            'interface': 'eth0', 'ip': '192.168.2.2',
+            'prefix_or_mask': '255.255.255.0', 'broadcast': '192.168.2.255'}
+        with net.EphemeralIPv4Network(**params):
+            self.assertEqual(expected_setup_calls, m_subp.call_args_list)
+        m_subp.assert_has_calls(expected_teardown_calls)
+
+    def test_ephemeral_ipv4_network_noop_when_configured(self, m_subp):
+        """EphemeralIPv4Network handles exception when address is setup.
+
+        It performs no cleanup as the interface was already setup.
+        """
+        params = {
+            'interface': 'eth0', 'ip': '192.168.2.2',
+            'prefix_or_mask': '255.255.255.0', 'broadcast': '192.168.2.255'}
+        m_subp.side_effect = ProcessExecutionError(
+            '', 'RTNETLINK answers: File exists', 2)
+        expected_calls = [
+            mock.call(
+                ['ip', '-family', 'inet', 'addr', 'add', '192.168.2.2/24',
+                 'broadcast', '192.168.2.255', 'dev', 'eth0'],
+                capture=True, update_env={'LANG': 'C'})]
+        with net.EphemeralIPv4Network(**params):
+            pass
+        self.assertEqual(expected_calls, m_subp.call_args_list)
+        self.assertIn(
+            'Skip ephemeral network setup, eth0 already has address',
+            self.logs.getvalue())
+
+    def test_ephemeral_ipv4_network_with_prefix(self, m_subp):
+        """EphemeralIPv4Network takes a valid prefix to setup the network."""
+        params = {
+            'interface': 'eth0', 'ip': '192.168.2.2',
+            'prefix_or_mask': '24', 'broadcast': '192.168.2.255'}
+        for prefix_val in ['24', 16]:  # prefix can be int or string
+            params['prefix_or_mask'] = prefix_val
+            with net.EphemeralIPv4Network(**params):
+                pass
+        m_subp.assert_has_calls([mock.call(
+            ['ip', '-family', 'inet', 'addr', 'add', '192.168.2.2/24',
+             'broadcast', '192.168.2.255', 'dev', 'eth0'],
+            capture=True, update_env={'LANG': 'C'})])
+        m_subp.assert_has_calls([mock.call(
+            ['ip', '-family', 'inet', 'addr', 'add', '192.168.2.2/16',
+             'broadcast', '192.168.2.255', 'dev', 'eth0'],
+            capture=True, update_env={'LANG': 'C'})])
+
+    def test_ephemeral_ipv4_network_with_new_default_route(self, m_subp):
+        """Add the route when router is set and no default route exists."""
+        params = {
+            'interface': 'eth0', 'ip': '192.168.2.2',
+            'prefix_or_mask': '255.255.255.0', 'broadcast': '192.168.2.255',
+            'router': '192.168.2.1'}
+        m_subp.return_value = '', ''  # Empty response from ip route gw check
+        expected_setup_calls = [
+            mock.call(
+                ['ip', '-family', 'inet', 'addr', 'add', '192.168.2.2/24',
+                 'broadcast', '192.168.2.255', 'dev', 'eth0'],
+                capture=True, update_env={'LANG': 'C'}),
+            mock.call(
+                ['ip', '-family', 'inet', 'link', 'set', 'dev', 'eth0', 'up'],
+                capture=True),
+            mock.call(
+                ['ip', 'route', 'show', '0.0.0.0/0'], capture=True),
+            mock.call(
+                ['ip', '-4', 'route', 'add', 'default', 'via',
+                 '192.168.2.1', 'dev', 'eth0'], capture=True)]
+        expected_teardown_calls = [mock.call(
+            ['ip', '-4', 'route', 'del', 'default', 'dev', 'eth0'],
+            capture=True)]
+
+        with net.EphemeralIPv4Network(**params):
+            self.assertEqual(expected_setup_calls, m_subp.call_args_list)
+        m_subp.assert_has_calls(expected_teardown_calls)
diff --git a/setup.py b/setup.py
index b1bde43..5c65c7f 100755
--- a/setup.py
+++ b/setup.py
@@ -240,7 +240,7 @@ setuptools.setup(
     author='Scott Moser',
     author_email='[e-mail]',
     url='http://launchpad.net/cloud-init/',
-    packages=setuptools.find_packages(exclude=['tests']),
+    packages=setuptools.find_packages(exclude=['tests.*', '*.tests', 'tests']),
     scripts=['tools/cloud-init-per'],
     license='Dual-licensed under GPLv3 or Apache 2.0',
     data_files=data_files,
diff --git a/tox.ini b/tox.ini
index 1140f9b..ef76884 100644
--- a/tox.ini
+++ b/tox.ini
@@ -21,7 +21,11 @@ setenv =
     LC_ALL = en_US.utf-8
 
 [testenv:pylint]
-deps = pylint==1.7.1
+deps = 
+    # requirements
+    pylint==1.7.1
+    # test-requirements because unit tests are now present in cloudinit tree 
+    -r{toxinidir}/test-requirements.txt
 commands = {envpython} -m pylint {posargs:cloudinit}
 
 [testenv:py3]
@@ -29,7 +33,7 @@ basepython = python3
 deps = -r{toxinidir}/test-requirements.txt
 commands = {envpython} -m nose {posargs:--with-coverage \
            --cover-erase --cover-branches --cover-inclusive \
-           --cover-package=cloudinit tests/unittests}
+           --cover-package=cloudinit tests/unittests cloudinit}
 
 [testenv:py27]
 basepython = python2.7
@@ -98,7 +102,11 @@ deps = pyflakes
 
 [testenv:tip-pylint]
 commands = {envpython} -m pylint {posargs:cloudinit}
-deps = pylint
+deps =
+    # requirements
+    pylint
+    # test-requirements
+    -r{toxinidir}/test-requirements.txt
 
 [testenv:citest]
 basepython = python3