86 lines
2.2 KiB
Python
86 lines
2.2 KiB
Python
# Copyright 2012 Bouvet ASA
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#
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# Author: Endre Karlson <endre.karlson@bouvet.no>
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#
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# Licensed under the Apache License, Version 2.0 (the "License"); you may
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# not use this file except in compliance with the License. You may obtain
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# a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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# License for the specific language governing permissions and limitations
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# under the License.
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import abc
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from stevedore import driver
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from moniker.openstack.common import log as logging
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LOG = logging.getLogger(__name__)
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class Plugin(object):
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__metaclass__ = abc.ABCMeta
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__plugin_ns__ = None
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__plugin_name__ = None
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__plugin_type__ = None
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def __init__(self):
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self.name = self.get_canonical_name()
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LOG.debug("Loaded plugin %s", self.name)
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def is_enabled(self):
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"""
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Is this Plugin enabled?
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:retval: Boolean
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"""
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return True
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@classmethod
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def get_plugin(cls, name, ns=None, invoke_on_load=False,
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invoke_args=(), invoke_kwds={}):
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"""
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Load a plugin from namespace
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"""
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ns = ns or cls.__plugin_ns__
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if ns is None:
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raise RuntimeError('No namespace provided or __plugin_ns__ unset')
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LOG.debug('Looking for plugin %s in %s', name, ns)
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mgr = driver.DriverManager(ns, name)
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return mgr.driver(*invoke_args, **invoke_kwds) if invoke_on_load \
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else mgr.driver
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@classmethod
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def get_canonical_name(cls):
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"""
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Return the plugin name
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"""
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type_ = cls.get_plugin_type()
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name = cls.get_plugin_name()
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return "%s:%s" % (type_, name)
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@classmethod
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def get_plugin_name(cls):
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return cls.__plugin_name__
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@classmethod
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def get_plugin_type(cls):
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return cls.__plugin_type__
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def start(self):
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"""
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Start this plugin
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"""
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def stop(self):
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"""
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Stop this plugin from doing anything
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"""
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