1 # Copyright (c) 2016-2017 Intel Corporation
3 # Licensed under the Apache License, Version 2.0 (the "License");
4 # you may not use this file except in compliance with the License.
5 # You may obtain a copy of the License at
7 # http://www.apache.org/licenses/LICENSE-2.0
9 # Unless required by applicable law or agreed to in writing, software
10 # distributed under the License is distributed on an "AS IS" BASIS,
11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 # See the License for the specific language governing permissions and
13 # limitations under the License.
14 """ AMQP Consumer senario definition """
16 from __future__ import absolute_import
17 from __future__ import print_function
20 from pika.exceptions import AMQPConnectionError
23 class AmqpConsumer(object):
24 """ This Class handles amqp consumer and collects collectd data """
25 EXCHANGE = 'amq.fanout'
26 EXCHANGE_TYPE = 'fanout'
28 ROUTING_KEY = 'collectd'
30 def __init__(self, amqp_url, queue):
31 self._connection = None
34 self._consumer_tag = None
39 """ connect to amqp url """
41 return pika.SelectConnection(pika.URLParameters(self._url),
42 self.on_connection_open,
43 stop_ioloop_on_close=False)
44 except AMQPConnectionError:
47 def on_connection_open(self, unused_connection):
48 """ call back from pika & open channel """
49 logging.info("list of unused connections %s", unused_connection)
50 self._connection.add_on_close_callback(self.on_connection_closed)
51 self._connection.channel(on_open_callback=self.on_channel_open)
53 def on_connection_closed(self, connection, reply_code, reply_text):
54 """ close the amqp connections. if force close, try re-connect """
55 logging.info("amqp connection (%s)", connection)
58 self._connection.ioloop.stop()
60 logging.debug(('Connection closed, reopening in 5 sec: (%s) %s',
61 reply_code, reply_text))
62 self._connection.add_timeout(5, self.reconnect)
65 """ re-connect amqp consumer"""
66 self._connection.ioloop.stop()
69 self._connection = self.connect()
70 self._connection.ioloop.start()
72 def on_channel_open(self, channel):
73 """ add close callback & setup exchange """
74 self._channel = channel
75 self.add_on_channel_close_callback()
76 self._channel.exchange_declare(self.on_exchange_declareok,
79 durable=True, auto_delete=False)
81 def add_on_channel_close_callback(self):
82 """ register for close callback """
83 self._channel.add_on_close_callback(self.on_channel_closed)
85 def on_channel_closed(self, channel, reply_code, reply_text):
86 """ close amqp channel connection """
87 logging.info("amqp channel closed channel(%s), "
88 "reply_code(%s) reply_text(%s)",
89 channel, reply_code, reply_text)
90 self._connection.close()
92 def on_exchange_declareok(self, unused_frame):
93 """ if exchange declare is ok, setup queue """
94 logging.info("amqp exchange unused frame (%s)", unused_frame)
95 self.setup_queue(self.QUEUE)
97 def setup_queue(self, queue_name):
98 """ setup queue & declare same with channel """
99 logging.info("amqp queue name (%s)", queue_name)
100 self._channel.queue_declare(self.on_queue_declareok, queue_name)
102 def on_queue_declareok(self, method_frame):
103 """ bind queue to channel """
104 logging.info("amqp queue method frame (%s)", method_frame)
105 self._channel.queue_bind(self._on_bindok, self.QUEUE,
106 self.EXCHANGE, self.ROUTING_KEY)
108 def _on_bindok(self, unused_frame):
109 """ call back on bind start consuming data from amqp queue """
110 logging.info("amqp unused frame %s", unused_frame)
111 self.add_on_cancel_callback()
112 self._consumer_tag = self._channel.basic_consume(self.on_message,
115 def add_on_cancel_callback(self):
116 """ add cancel func to amqp callback """
117 self._channel.add_on_cancel_callback(self.on_consumer_cancelled)
119 def on_consumer_cancelled(self, method_frame):
120 """ on cancel close the channel """
121 logging.info("amqp method frame %s", method_frame)
123 self._channel.close()
125 def on_message(self, unused_channel, basic_deliver, properties, body):
126 """ parse received data from amqp server (collectd) """
127 logging.info("amqp unused channel %s, properties %s",
128 unused_channel, properties)
129 metrics = body.rsplit()
130 self._queue.put({metrics[1]: metrics[3]})
131 self.ack_message(basic_deliver.delivery_tag)
133 def ack_message(self, delivery_tag):
134 """ acknowledge amqp msg """
135 self._channel.basic_ack(delivery_tag)
137 def on_cancelok(self, unused_frame):
138 """ initiate amqp close channel on callback """
139 logging.info("amqp unused frame %s", unused_frame)
140 self._channel.close()
143 """ Initiate amqp connection. """
144 self._connection = self.connect()
145 self._connection.ioloop.start()
148 """ stop amqp consuming data """
151 self._channel.basic_cancel(self.on_cancelok, self._consumer_tag)
154 self._connection.ioloop.start()
156 def close_connection(self):
157 """ close amqp connection """
158 self._connection.close()