2d82f972f0b9bea4c635dcbcb5689ec7547d9bb1
4 from aiokafka
import AIOKafkaConsumer
5 from aiokafka
import AIOKafkaProducer
6 from aiokafka
.errors
import KafkaError
7 from osm_common
.msgbase
import MsgBase
, MsgException
10 __author__
= "Alfonso Tierno <alfonso.tiernosepulveda@telefonica.com>, " \
11 "Guillermo Calvino <guillermo.calvinosanchez@altran.com>"
14 class MsgKafka(MsgBase
):
15 def __init__(self
, logger_name
='msg'):
16 self
.logger
= logging
.getLogger(logger_name
)
24 def connect(self
, config
):
26 if "logger_name" in config
:
27 self
.logger
= logging
.getLogger(config
["logger_name"])
28 self
.host
= config
["host"]
29 self
.port
= config
["port"]
30 self
.loop
= asyncio
.get_event_loop()
31 self
.broker
= str(self
.host
) + ":" + str(self
.port
)
33 except Exception as e
: # TODO refine
34 raise MsgException(str(e
))
40 except Exception as e
: # TODO refine
41 raise MsgException(str(e
))
43 def write(self
, topic
, key
, msg
):
45 Write a message at kafka bus
46 :param topic: message topic, must be string
47 :param key: message key, must be string
48 :param msg: message content, can be string or dictionary
49 :return: None or raises MsgException on failing
52 self
.loop
.run_until_complete(self
.aiowrite(topic
=topic
, key
=key
, msg
=msg
))
54 except Exception as e
:
55 raise MsgException("Error writing {} topic: {}".format(topic
, str(e
)))
57 def read(self
, topic
):
59 Read from one or several topics.
60 :param topic: can be str: single topic; or str list: several topics
61 :return: topic, key, message; or None
64 return self
.loop
.run_until_complete(self
.aioread(topic
, self
.loop
))
67 except Exception as e
:
68 raise MsgException("Error reading {} topic: {}".format(topic
, str(e
)))
70 async def aiowrite(self
, topic
, key
, msg
, loop
=None):
75 self
.producer
= AIOKafkaProducer(loop
=loop
, key_serializer
=str.encode
, value_serializer
=str.encode
,
76 bootstrap_servers
=self
.broker
)
77 await self
.producer
.start()
78 await self
.producer
.send(topic
=topic
, key
=key
, value
=yaml
.safe_dump(msg
, default_flow_style
=True))
79 except Exception as e
:
80 raise MsgException("Error publishing topic '{}', key '{}': {}".format(topic
, key
, e
))
82 await self
.producer
.stop()
84 async def aioread(self
, topic
, loop
=None, callback
=None, *args
):
86 Asyncio read from one or several topics. It blocks
87 :param topic: can be str: single topic; or str list: several topics
88 :param loop: asyncio loop
89 :callback: callback function that will handle the message in kafka bus
90 :*args: optional arguments for callback function
91 :return: topic, key, message
97 if isinstance(topic
, (list, tuple)):
100 topic_list
= (topic
,)
102 self
.consumer
= AIOKafkaConsumer(loop
=loop
, bootstrap_servers
=self
.broker
)
103 await self
.consumer
.start()
104 self
.consumer
.subscribe(topic_list
)
106 async for message
in self
.consumer
:
108 callback(message
.topic
, yaml
.load(message
.key
), yaml
.load(message
.value
), *args
)
110 return message
.topic
, yaml
.load(message
.key
), yaml
.load(message
.value
)
111 except KafkaError
as e
:
112 raise MsgException(str(e
))
114 await self
.consumer
.stop()