1 # -*- coding: utf-8 -*-
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
13 # See the License for the specific language governing permissions and
14 # limitations under the License.
19 from aiokafka
import AIOKafkaConsumer
20 from aiokafka
import AIOKafkaProducer
21 from aiokafka
.errors
import KafkaError
22 from osm_common
.msgbase
import MsgBase
, MsgException
25 "Alfonso Tierno <alfonso.tiernosepulveda@telefonica.com>, "
26 "Guillermo Calvino <guillermo.calvinosanchez@altran.com>"
30 class MsgKafka(MsgBase
):
31 def __init__(self
, logger_name
="msg", lock
=False):
32 super().__init
__(logger_name
, lock
)
41 def connect(self
, config
):
43 if "logger_name" in config
:
44 self
.logger
= logging
.getLogger(config
["logger_name"])
45 self
.host
= config
["host"]
46 self
.port
= config
["port"]
47 self
.loop
= config
.get("loop") or asyncio
.get_event_loop()
48 self
.broker
= str(self
.host
) + ":" + str(self
.port
)
49 self
.group_id
= config
.get("group_id")
51 except Exception as e
: # TODO refine
52 raise MsgException(str(e
))
58 except Exception as e
: # TODO refine
59 raise MsgException(str(e
))
61 def write(self
, topic
, key
, msg
):
63 Write a message at kafka bus
64 :param topic: message topic, must be string
65 :param key: message key, must be string
66 :param msg: message content, can be string or dictionary
67 :return: None or raises MsgException on failing
69 retry
= 2 # Try two times
72 self
.loop
.run_until_complete(
73 self
.aiowrite(topic
=topic
, key
=key
, msg
=msg
)
76 except Exception as e
:
80 "Error writing {} topic: {}".format(topic
, str(e
))
83 def read(self
, topic
):
85 Read from one or several topics.
86 :param topic: can be str: single topic; or str list: several topics
87 :return: topic, key, message; or None
90 return self
.loop
.run_until_complete(self
.aioread(topic
, self
.loop
))
93 except Exception as e
:
94 raise MsgException("Error reading {} topic: {}".format(topic
, str(e
)))
96 async def aiowrite(self
, topic
, key
, msg
, loop
=None):
99 :param topic: str kafka topic
100 :param key: str kafka key
101 :param msg: str or dictionary kafka message
102 :param loop: asyncio loop. To be DEPRECATED! in near future!!! loop must be provided inside config at connect
109 self
.producer
= AIOKafkaProducer(
111 key_serializer
=str.encode
,
112 value_serializer
=str.encode
,
113 bootstrap_servers
=self
.broker
,
115 await self
.producer
.start()
116 await self
.producer
.send(
117 topic
=topic
, key
=key
, value
=yaml
.safe_dump(msg
, default_flow_style
=True)
119 except Exception as e
:
121 "Error publishing topic '{}', key '{}': {}".format(topic
, key
, e
)
124 await self
.producer
.stop()
137 Asyncio read from one or several topics.
138 :param topic: can be str: single topic; or str list: several topics
139 :param loop: asyncio loop. To be DEPRECATED! in near future!!! loop must be provided inside config at connect
140 :param callback: synchronous callback function that will handle the message in kafka bus
141 :param aiocallback: async callback function that will handle the message in kafka bus
142 :param group_id: kafka group_id to use. Can be False (set group_id to None), None (use general group_id provided
143 at connect inside config), or a group_id string
144 :param from_beginning: if True, messages will be obtained from beginning instead of only new ones.
145 If group_id is supplied, only the not processed messages by other worker are obtained.
146 If group_id is None, all messages stored at kafka are obtained.
147 :param kwargs: optional keyword arguments for callback function
148 :return: If no callback defined, it returns (topic, key, message)
153 if group_id
is False:
155 elif group_id
is None:
156 group_id
= self
.group_id
158 if isinstance(topic
, (list, tuple)):
161 topic_list
= (topic
,)
162 self
.consumer
= AIOKafkaConsumer(
164 bootstrap_servers
=self
.broker
,
166 auto_offset_reset
="earliest" if from_beginning
else "latest",
168 await self
.consumer
.start()
169 self
.consumer
.subscribe(topic_list
)
171 async for message
in self
.consumer
:
175 yaml
.safe_load(message
.key
),
176 yaml
.safe_load(message
.value
),
182 yaml
.safe_load(message
.key
),
183 yaml
.safe_load(message
.value
),
189 yaml
.safe_load(message
.key
),
190 yaml
.safe_load(message
.value
),
192 except KafkaError
as e
:
193 raise MsgException(str(e
))
195 await self
.consumer
.stop()