os-vif/os_vif/plugin.py
Eric Fried 8d7c0d548d doc: Fix arg specs and object types in docs
The usage doc stated that plug and unplug accept a single argument of
type `os_vif.objects.VIF`, which isn't a thing, and then went on to give
an example showing that they take two.  The usage doc and the plug and
unplug docstrings also listed various objects at the wrong paths (e.g.
the `instance_info` param being of type `os_vif.objects.InstanceInfo`,
which also isn't a thing).

Fixed up the usage doc to list both arguments and correct the references
in the sample code; and fixed the plug/unplug docstrings
to list the proper paths to classes: os_vif.objects.vif.VIFBase and
os_vif.objects.instance_info.InstanceInfo.

Made everything in `single backticks` into a proper rst ``literal``.

Change-Id: I400838bbe9663917fe2c64f52975b77a370405b4
2018-07-16 17:55:22 +01:00

92 lines
3.0 KiB
Python

# 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
from oslo_config import cfg
import six
CONF = cfg.CONF
@six.add_metaclass(abc.ABCMeta)
class PluginBase(object):
"""Base class for all VIF plugins."""
# Override to provide a tuple of oslo_config.Opt instances for
# the plugin config parameters
CONFIG_OPTS = ()
def __init__(self, config):
"""
Initialize the plugin object with the provided config
:param config: ``oslo_config.ConfigOpts.GroupAttr`` instance:
"""
self.config = config
@abc.abstractmethod
def describe(self):
"""
Return an object that describes the plugin's supported vif types and
the earliest/latest known VIF object versions.
:returns: A ``os_vif.objects.host_info.HostPluginInfo`` instance
"""
@abc.abstractmethod
def plug(self, vif, instance_info):
"""
Given a model of a VIF, perform operations to plug the VIF properly.
:param vif: ``os_vif.objects.vif.VIFBase`` object.
:param instance_info: ``os_vif.objects.instance_info.InstanceInfo``
object.
:raises ``processutils.ProcessExecutionError``. Plugins implementing
this method should let `processutils.ProcessExecutionError`
bubble up.
"""
@abc.abstractmethod
def unplug(self, vif, instance_info):
"""
Given a model of a VIF, perform operations to unplug the VIF properly.
:param vif: ``os_vif.objects.vif.VIFBase`` object.
:param instance_info: ``os_vif.objects.instance_info.InstanceInfo``
object.
:raises ``processutils.ProcessExecutionError``. Plugins implementing
this method should let ``processutils.ProcessExecutionError``
bubble up.
"""
@classmethod
def load(cls, plugin_name):
"""
Load a plugin, registering its configuration options
:param plugin_name: the name of the plugin extension
:returns: an initialized instance of the class
"""
cfg_group_name = "os_vif_" + plugin_name
cfg_opts = getattr(cls, "CONFIG_OPTS")
cfg_vals = None
if cfg_opts and len(cfg_opts) > 0:
cfg_group = cfg.OptGroup(
cfg_group_name,
"os-vif plugin %s options" % plugin_name)
CONF.register_opts(cfg_opts, group=cfg_group)
cfg_vals = getattr(CONF, cfg_group_name)
return cls(cfg_vals)