Add the base classes for the new OS utils architecture

The base classes follows the OS utils architecture spec.

Change-Id: I1365e6c9de20dccc905e35113ccdea03f2a03f1b

cloudinit/osys/base.py

@@ -0,0 +1,77 @@
+# Copyright (C) 2015 Canonical Ltd.
+# Copyright 2015 Cloudbase Solutions Srl
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import abc
+import importlib
+import platform
+
+import six
+
+
+__all__ = (
+    'get_osutils',
+    'OSUtils',
+)
+
+
+def get_osutils():
+    """Obtain the OS utils object for the underlying platform."""
+    name, _, _ = platform.linux_distribution()
+    if not name:
+        name = platform.system()
+
+    name = name.lower()
+    location = "cloudinit.osys.{0}.base".format(name)
+    module = importlib.import_module(location)
+    return module.OSUtils
+
+
+@six.add_metaclass(abc.ABCMeta)
+class OSUtils(object):
+    """Base class for an OS utils namespace.
+
+    This base class provides a couple of hooks which needs to be
+    implemented by subclasses, for each particular OS and distro.
+    """
+
+    name = None
+
+    @abc.abstractproperty
+    def network(self):
+        """Get the network object for the underlying platform."""
+
+    @abc.abstractproperty
+    def filesystem(self):
+        """Get the filesystem object for the underlying platform."""
+
+    @abc.abstractproperty
+    def users(self):
+        """Get the users object for the underlying platform."""
+
+    @abc.abstractproperty
+    def general(self):
+        """Get the general object for the underlying platform."""
+
+    @abc.abstractproperty
+    def user_class(self):
+        """Get the user class specific to this operating system."""
+
+    @abc.abstractproperty
+    def route_class(self):
+        """Get the route class specific to this operating system."""
+
+    @abc.abstractproperty
+    def interface_class(self):
+        """Get the interface class specific to this operating system."""

cloudinit/osys/general.py

@@ -0,0 +1,43 @@
+# Copyright (C) 2015 Canonical Ltd.
+# Copyright 2015 Cloudbase Solutions Srl
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import abc
+
+import six
+
+
+@six.add_metaclass(abc.ABCMeta)
+class General(object):
+    """Base class for the general namespace.
+
+    This class should contain common functions between all OSes,
+    which can't be grouped in a domain-specific namespace.
+    """
+
+    @abc.abstractmethod
+    def set_timezone(self, timezone):
+        """Change the timezone for the underlying platform.
+
+        The `timezone` parameter should be a TZID timezone format,
+        e.g. 'Africa/Mogadishu'
+        """
+
+    @abc.abstractmethod
+    def set_locale(self, locale):
+        """Change the locale for the underlying platform."""
+
+    @abc.abstractmethod
+    def reboot(self):
+        pass

cloudinit/osys/network.py

@@ -0,0 +1,152 @@
+# Copyright (C) 2015 Canonical Ltd.
+# Copyright 2015 Cloudbase Solutions Srl
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import abc
+
+import six
+
+from cloudinit import util
+
+
+__all__ = (
+    'Network',
+    'Route',
+    'Interface',
+)
+
+
+@six.add_metaclass(abc.ABCMeta)
+class Network(object):
+    """Base network class for network related utilities."""
+
+    @abc.abstractmethod
+    def routes(self):
+        """Get the list of the available routes."""
+
+    @abc.abstractmethod
+    def default_gateway(self):
+        """Get the default gateway, as a route object."""
+
+    @abc.abstractmethod
+    def interfaces(self):
+        """Get the list of the available interfaces."""
+
+    @abc.abstractmethod
+    def hosts(self):
+        """Get the list of the available hosts."""
+
+    @abc.abstractmethod
+    def set_hostname(self, hostname):
+        """Change the host name of the instance."""
+
+    @abc.abstractmethod
+    def set_static_network_config(self, adapter_name, address, netmask,
+                                  broadcast, gateway, dnsnameservers):
+        """Configure a new static network."""
+
+
+@six.add_metaclass(abc.ABCMeta)
+class Route(object):
+    """Base class for routes."""
+
+    def __init__(self, destination, gateway, netmask,
+                 interface, metric,
+                 flags=None, refs=None, use=None, expire=None):
+        self.destination = destination
+        self.gateway = gateway
+        self.netmask = netmask
+        self.interface = interface
+        self.metric = metric
+        self.flags = flags
+        self.refs = refs
+        self.use = use
+        self.expire = expire
+
+    @abc.abstractproperty
+    def is_static(self):
+        """Check if this route is static."""
+
+    @util.abstractclassmethod
+    def add(cls, route):
+        """Add a new route in the underlying OS.
+
+        The `route` parameter should be an instance of :class:`Route`.
+        """
+
+    @util.abstractclassmethod
+    def delete(cls, route):
+        """Delete a route from the underlying OS.
+
+        The `route` parameter should be an instance of :class:`Route`.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class Interface(object):
+    """Base class reprensenting an interface.
+
+    It provides both attributes for retrieving interface information,
+    as well as methods for modifying the state of a route, such
+    as activating or deactivating it.
+    """
+
+    def __init__(self, name, mac, index=None, mtu=None,
+                 dhcp_server=None, dhcp_enabled=None):
+        self._mtu = mtu
+
+        self.name = name
+        self.index = index
+        self.mac = mac
+        self.dhcp_server = dhcp_server
+        self.dhcp_enabled = dhcp_enabled
+
+    def __eq__(self, other):
+        return (self.mac == other.mac and
+                self.name == other.name and
+                self.index == other.index)
+
+    @abc.abstractmethod
+    def _change_mtu(self, value):
+        """Change the mtu for the underlying interface."""
+
+    @util.abstractclassmethod
+    def from_name(cls, name):
+        """Get an instance of :class:`Interface` from an interface name.
+
+        E.g. this should retrieve the 'eth0' interface::
+
+           >>> Interface.from_name('eth0')
+        """
+
+    @abc.abstractmethod
+    def up(self):
+        """Activate the current interface."""
+
+    @abc.abstractmethod
+    def down(self):
+        """Deactivate the current interface."""
+
+    @abc.abstractmethod
+    def is_up(self):
+        """Check if this interface is activated."""
+
+    @property
+    def mtu(self):
+        return self._mtu
+
+    @mtu.setter
+    def mtu(self, value):
+        self._change_mtu(value)
+        self._mtu = value

cloudinit/osys/users.py

@@ -0,0 +1,67 @@
+# Copyright (C) 2015 Canonical Ltd.
+# Copyright 2015 Cloudbase Solutions Srl
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import abc
+
+import six
+
+from cloudinit import util
+
+
+@six.add_metaclass(abc.ABCMeta)
+class Users(object):
+    """Base class for user related operations."""
+
+    @abc.abstractmethod
+    def groups(self):
+        """Get a list of the groups available in the system."""
+
+    @abc.abstractmethod
+    def users(self):
+        """Get a list of the users available in the system."""
+
+
+@six.add_metaclass(abc.ABCMeta)
+class Group(object):
+    """Base class for user groups."""
+
+    @util.abstractclassmethod
+    def create(cls, group_name):
+        """Create a new group with the given name."""
+
+    @abc.abstractmethod
+    def add(self, member):
+        """Add a new member to this group."""
+
+
+@six.add_metaclass(abc.ABCMeta)
+class User(object):
+    """Base class for an user."""
+
+    @classmethod
+    def create(self, username, password, **kwargs):
+        """Create a new user."""
+
+    @abc.abstractmethod
+    def home(self):
+        """Get the user's home directory."""
+
+    @abc.abstractmethod
+    def ssh_keys(self):
+        """Get the ssh keys for this user."""
+
+    @abc.abstractmethod
+    def change_password(self, password):
+        """Change the password for this user."""

cloudinit/tests/osys/test_base.py

@@ -0,0 +1,50 @@
+# Copyright (C) 2015 Canonical Ltd.
+# Copyright 2015 Cloudbase Solutions Srl
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import unittest
+
+try:
+    import unittest.mock as mock
+except ImportError:
+    import mock
+
+from cloudinit.osys import base
+
+
+class TestOSUtils(unittest.TestCase):
+
+    @mock.patch('importlib.import_module')
+    @mock.patch('platform.linux_distribution')
+    @mock.patch('platform.system')
+    def _test_getosutils(self, mock_system,
+                         mock_linux_distribution, mock_import_module,
+                         linux=False):
+        if linux:
+            os_name = 'Linux'
+        else:
+            os_name = 'Windows'
+
+        mock_system.return_value = os_name
+        mock_linux_distribution.return_value = (os_name, None, None)
+        module = base.get_osutils()
+
+        mock_import_module.assert_called_once_with(
+            "cloudinit.osys.{0}.base".format(os_name.lower()))
+        self.assertEqual(mock_import_module.return_value.OSUtils,
+                         module)
+
+    def test_getosutils(self):
+        self._test_getosutils(linux=True)
+        self._test_getosutils(linux=False)

cloudinit/util.py

@@ -0,0 +1,26 @@
+# Copyright (C) 2015 Canonical Ltd.
+# Copyright (C) 2015 Cloudbase Solutions Srl
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+__all__ = ('abstractclassmethod', )
+
+
+class abstractclassmethod(classmethod):
+    """A backport for abc.abstractclassmethod from Python 3."""
+
+    __isabstractmethod__ = True
+
+    def __init__(self, func):
+        func.__isabstractmethod__ = True
+        super(abstractclassmethod, self).__init__(func)