+import logging
+import asyncio
+import yaml
from aiokafka import AIOKafkaConsumer
from aiokafka import AIOKafkaProducer
from aiokafka.errors import KafkaError
from msgbase import MsgBase, MsgException
-import asyncio
-import yaml
#import json
-class msgKafka(MsgBase):
- def __init__(self):
+
+class MsgKafka(MsgBase):
+ def __init__(self, logger_name='msg'):
+ self.logger = logging.getLogger(logger_name)
self.host = None
self.port = None
self.consumer = None
def connect(self, config):
try:
+ if "logger_name" in config:
+ self.logger = logging.getLogger(config["logger_name"])
self.host = config["host"]
self.port = config["port"]
self.topic_lst = []
except Exception as e: # TODO refine
raise MsgException(str(e))
- def write(self, topic, msg, key):
+ def disconnect(self):
+ try:
+ self.loop.close()
+ except Exception as e: # TODO refine
+ raise MsgException(str(e))
+ def write(self, topic, key, msg):
try:
- self.loop.run_until_complete(self.aiowrite(key, msg=yaml.safe_dump(msg, default_flow_style=True), topic=topic))
+ self.loop.run_until_complete(self.aiowrite(topic=topic, key=key,
+ msg=yaml.safe_dump(msg, default_flow_style=True),
+ loop=self.loop))
except Exception as e:
raise MsgException("Error writing {} topic: {}".format(topic, str(e)))
def read(self, topic):
- self.topic_lst.append(topic)
+ """
+ Read from one or several topics. it is non blocking returning None if nothing is available
+ :param topic: can be str: single topic; or str list: several topics
+ :return: topic, key, message; or None
+ """
try:
- return self.loop.run_until_complete(self.aioread(self.topic_lst))
+ return self.loop.run_until_complete(self.aioread(topic, self.loop))
+ except MsgException:
+ raise
except Exception as e:
raise MsgException("Error reading {} topic: {}".format(topic, str(e)))
- async def aiowrite(self, key, msg, topic):
+ async def aiowrite(self, topic, key, msg, loop):
try:
- self.producer = AIOKafkaProducer(loop=self.loop, key_serializer=str.encode, value_serializer=str.encode,
+ self.producer = AIOKafkaProducer(loop=loop, key_serializer=str.encode, value_serializer=str.encode,
bootstrap_servers=self.broker)
await self.producer.start()
await self.producer.send(topic=topic, key=key, value=msg)
finally:
await self.producer.stop()
- async def aioread(self, topic):
- self.consumer = AIOKafkaConsumer(loop=self.loop, bootstrap_servers=self.broker)
- await self.consumer.start()
- self.consumer.subscribe(topic)
+ async def aioread(self, topic, loop):
+ """
+ Asyncio read from one or several topics. It blocks
+ :param topic: can be str: single topic; or str list: several topics
+ :param loop: asyncio loop
+ :return: topic, key, message
+ """
try:
+ if isinstance(topic, (list, tuple)):
+ topic_list = topic
+ else:
+ topic_list = (topic,)
+
+ self.consumer = AIOKafkaConsumer(loop=loop, bootstrap_servers=self.broker)
+ await self.consumer.start()
+ self.consumer.subscribe(topic_list)
async for message in self.consumer:
- return yaml.load(message.key), yaml.load(message.value)
+ return message.topic, yaml.load(message.key), yaml.load(message.value)
except KafkaError as e:
raise MsgException(str(e))
finally: