# -*- encoding: utf-8 -*-
#
# Copyright © 2012 New Dream Network, LLC (DreamHost)
#
# Author: <NAME> <<EMAIL>>
#
# 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.
"""Base class for plugins.
"""

import abc
import collections


ExchangeTopics = collections.namedtuple('ExchangeTopics',
                                        ['exchange', 'topics'])


class PluginBase(object):
    """Base class for all plugins.
    """

    def is_enabled(self):
        """Return boolean indicating whether this plugin should
        be enabled and used by the caller.
        """
        return True


class NotificationBase(PluginBase):
    """Base class for plugins that support the notification API."""

    __metaclass__ = abc.ABCMeta

    def is_enabled(self):
        return True

    @abc.abstractmethod
    def get_event_types(self):
        """Return a sequence of strings defining the event types to be
        given to this plugin."""

    @abc.abstractmethod
    def get_exchange_topics(self, conf):
        """Return a sequence of ExchangeTopics defining the exchange and
        topics to be connected for this plugin.

        :param conf: Configuration.
        """

    @abc.abstractmethod
    def process_notification(self, message):
        """Return a sequence of Counter instances for the given message.

        :param message: Message to process."""

    def notification_to_metadata(self, event):
        """Transform a payload dict to a metadata dict."""
        metadata = dict([(k, event['payload'].get(k))
                         for k in self.metadata_keys])
        metadata['event_type'] = event['event_type']
        metadata['host'] = event['publisher_id']
        return metadata


class PollsterBase(PluginBase):
    """Base class for plugins that support the polling API."""

    __metaclass__ = abc.ABCMeta

    @abc.abstractmethod
    def get_counter_names(self):
        """Return a sequence of Counter names supported by the pollster."""

    @abc.abstractmethod
    def get_counters(self, manager, instance):
        """Return a sequence of Counter instances from polling the
        resources."""


class PublisherBase(PluginBase):
    """Base class for plugins that publish the sampler."""

    __metaclass__ = abc.ABCMeta

    @abc.abstractmethod
    def publish_counters(self, context, counters, source):
        "Publish counters into final conduit."


class TransformerBase(PluginBase):
    """Base class for plugins that transform the counter."""

    __metaclass__ = abc.ABCMeta

    @abc.abstractmethod
    def handle_sample(self, context, counter, source):
        """Transform a counter.

        :param context: Passed from the data collector.
        :param counter: A counter.
        :param source: Passed from data collector.
        """

    def flush(self, context, source):
        """Flush counters cached previously.

        :param context: Passed from the data collector.
        :param source: Source of counters that are being published."""
        return []

    def __init__(self, **kwargs):
        """Setup transformer.

        Each time a transformed is involved in a pipeline, a new transformer
        instance is created and chained into the pipeline. i.e. transformer
        instance is per pipeline. This helps if transformer need keep some
        cache and per-pipeline information.

        :param kwargs: The parameters that are defined in pipeline config file.
        """
        super(TransformerBase, self).__init__()

# -*- encoding: utf-8 -*-
#
# Copyright © 2012 New Dream Network, LLC (DreamHost)
#
# Author: <NAME> <<EMAIL>>
#
# 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.
"""Base class for plugins.
"""

import abc
import collections


ExchangeTopics = collections.namedtuple('ExchangeTopics',
                                        ['exchange', 'topics'])


class PluginBase(object):
    """Base class for all plugins.
    """

    def is_enabled(self):
        """Return boolean indicating whether this plugin should
        be enabled and used by the caller.
        """
        return True


class NotificationBase(PluginBase):
    """Base class for plugins that support the notification API."""

    __metaclass__ = abc.ABCMeta

    def is_enabled(self):
        return True

    @abc.abstractmethod
    def get_event_types(self):
        """Return a sequence of strings defining the event types to be
        given to this plugin."""

    @abc.abstractmethod
    def get_exchange_topics(self, conf):
        """Return a sequence of ExchangeTopics defining the exchange and
        topics to be connected for this plugin.

        :param conf: Configuration.
        """

    @abc.abstractmethod
    def process_notification(self, message):
        """Return a sequence of Counter instances for the given message.

        :param message: Message to process."""

    def notification_to_metadata(self, event):
        """Transform a payload dict to a metadata dict."""
        metadata = dict([(k, event['payload'].get(k))
                         for k in self.metadata_keys])
        metadata['event_type'] = event['event_type']
        metadata['host'] = event['publisher_id']
        return metadata


class PollsterBase(PluginBase):
    """Base class for plugins that support the polling API."""

    __metaclass__ = abc.ABCMeta

    @abc.abstractmethod
    def get_counter_names(self):
        """Return a sequence of Counter names supported by the pollster."""

    @abc.abstractmethod
    def get_counters(self, manager, instance):
        """Return a sequence of Counter instances from polling the
        resources."""


class PublisherBase(PluginBase):
    """Base class for plugins that publish the sampler."""

    __metaclass__ = abc.ABCMeta

    @abc.abstractmethod
    def publish_counters(self, context, counters, source):
        "Publish counters into final conduit."


class TransformerBase(PluginBase):
    """Base class for plugins that transform the counter."""

    __metaclass__ = abc.ABCMeta

    @abc.abstractmethod
    def handle_sample(self, context, counter, source):
        """Transform a counter.

        :param context: Passed from the data collector.
        :param counter: A counter.
        :param source: Passed from data collector.
        """

    def flush(self, context, source):
        """Flush counters cached previously.

        :param context: Passed from the data collector.
        :param source: Source of counters that are being published."""
        return []

    def __init__(self, **kwargs):
        """Setup transformer.

        Each time a transformed is involved in a pipeline, a new transformer
        instance is created and chained into the pipeline. i.e. transformer
        instance is per pipeline. This helps if transformer need keep some
        cache and per-pipeline information.

        :param kwargs: The parameters that are defined in pipeline config file.
        """
        super(TransformerBase, self).__init__()

# -*- encoding: utf-8 -*- # # Copyright © 2012 New Dream Network, LLC (DreamHost) # # Author: <NAME> <<EMAIL>> # # 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. Base class for plugins. Base class for all plugins. Return boolean indicating whether this plugin should         be enabled and used by the caller. Base class for plugins that support the notification API. Return a sequence of strings defining the event types to be         given to this plugin. Return a sequence of ExchangeTopics defining the exchange and         topics to be connected for this plugin.          :param conf: Configuration. Return a sequence of Counter instances for the given message.          :param message: Message to process. Transform a payload dict to a metadata dict. Base class for plugins that support the polling API. Return a sequence of Counter names supported by the pollster. Return a sequence of Counter instances from polling the         resources. Base class for plugins that publish the sampler. Base class for plugins that transform the counter. Transform a counter.          :param context: Passed from the data collector.         :param counter: A counter.         :param source: Passed from data collector. Flush counters cached previously.          :param context: Passed from the data collector.         :param source: Source of counters that are being published. Setup transformer.          Each time a transformed is involved in a pipeline, a new transformer         instance is created and chained into the pipeline. i.e. transformer         instance is per pipeline. This helps if transformer need keep some         cache and per-pipeline information.          :param kwargs: The parameters that are defined in pipeline config file.