+# -*- coding: utf-8 -*-
+
+# 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.
+
import logging
import asyncio
import yaml
from aiokafka import AIOKafkaProducer
from aiokafka.errors import KafkaError
from osm_common.msgbase import MsgBase, MsgException
-# import json
__author__ = "Alfonso Tierno <alfonso.tiernosepulveda@telefonica.com>, " \
"Guillermo Calvino <guillermo.calvinosanchez@altran.com>"
class MsgKafka(MsgBase):
- def __init__(self, logger_name='msg'):
- self.logger = logging.getLogger(logger_name)
+ def __init__(self, logger_name='msg', lock=False):
+ super().__init__(logger_name, lock)
self.host = None
self.port = None
self.consumer = None
self.producer = None
self.loop = None
self.broker = None
+ self.group_id = None
def connect(self, config):
try:
self.logger = logging.getLogger(config["logger_name"])
self.host = config["host"]
self.port = config["port"]
- self.loop = asyncio.get_event_loop()
+ self.loop = config.get("loop") or asyncio.get_event_loop()
self.broker = str(self.host) + ":" + str(self.port)
+ self.group_id = config.get("group_id")
except Exception as e: # TODO refine
raise MsgException(str(e))
def disconnect(self):
try:
- self.loop.close()
+ pass
+ # 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(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)))
+ """
+ Write a message at kafka bus
+ :param topic: message topic, must be string
+ :param key: message key, must be string
+ :param msg: message content, can be string or dictionary
+ :return: None or raises MsgException on failing
+ """
+ retry = 2 # Try two times
+ while retry:
+ try:
+ self.loop.run_until_complete(self.aiowrite(topic=topic, key=key, msg=msg))
+ break
+ except Exception as e:
+ retry -= 1
+ if retry == 0:
+ raise MsgException("Error writing {} topic: {}".format(topic, str(e)))
def read(self, topic):
"""
- Read from one or several topics. it is non blocking returning None if nothing is available
+ Read from one or several topics.
:param topic: can be str: single topic; or str list: several topics
:return: topic, key, message; or None
"""
raise MsgException("Error reading {} topic: {}".format(topic, str(e)))
async def aiowrite(self, topic, key, msg, loop=None):
+ """
+ Asyncio write
+ :param topic: str kafka topic
+ :param key: str kafka key
+ :param msg: str or dictionary kafka message
+ :param loop: asyncio loop. To be DEPRECATED! in near future!!! loop must be provided inside config at connect
+ :return: None
+ """
if not loop:
loop = self.loop
finally:
await self.producer.stop()
- async def aioread(self, topic, loop=None, callback=None, *args):
+ async def aioread(self, topic, loop=None, callback=None, aiocallback=None, group_id=None, **kwargs):
"""
- Asyncio read from one or several topics. It blocks
+ Asyncio read from one or several topics.
:param topic: can be str: single topic; or str list: several topics
- :param loop: asyncio loop
- :callback: callback function that will handle the message in kafka bus
- :*args: optional arguments for callback function
- :return: topic, key, message
+ :param loop: asyncio loop. To be DEPRECATED! in near future!!! loop must be provided inside config at connect
+ :param callback: synchronous callback function that will handle the message in kafka bus
+ :param aiocallback: async callback function that will handle the message in kafka bus
+ :param group_id: kafka group_id to use. Can be False (set group_id to None), None (use general group_id provided
+ at connect inside config), or a group_id string
+ :param kwargs: optional keyword arguments for callback function
+ :return: If no callback defined, it returns (topic, key, message)
"""
if not loop:
loop = self.loop
+ if group_id is False:
+ group_id = None
+ elif group_id is None:
+ group_id = self.group_id
try:
if isinstance(topic, (list, tuple)):
topic_list = topic
else:
topic_list = (topic,)
- self.consumer = AIOKafkaConsumer(loop=loop, bootstrap_servers=self.broker)
+ self.consumer = AIOKafkaConsumer(loop=loop, bootstrap_servers=self.broker, group_id=group_id)
await self.consumer.start()
self.consumer.subscribe(topic_list)
async for message in self.consumer:
if callback:
- callback(message.topic, yaml.load(message.key), yaml.load(message.value), *args)
+ callback(message.topic, yaml.safe_load(message.key), yaml.safe_load(message.value), **kwargs)
+ elif aiocallback:
+ await aiocallback(message.topic, yaml.safe_load(message.key), yaml.safe_load(message.value),
+ **kwargs)
else:
- return message.topic, yaml.load(message.key), yaml.load(message.value)
+ return message.topic, yaml.safe_load(message.key), yaml.safe_load(message.value)
except KafkaError as e:
raise MsgException(str(e))
finally: