monasca-events-api/monasca_events_api/common/messaging/kafka_publisher.py

111 lines
4.0 KiB
Python

# Copyright 2014 Hewlett-Packard
#
# 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 time
from kafka import client
from kafka import common
from kafka import producer
from oslo.config import cfg
from monasca_events_api.common.messaging import exceptions
from monasca_events_api.common.messaging import publisher
from monasca_events_api.openstack.common import log
LOG = log.getLogger(__name__)
class KafkaPublisher(publisher.Publisher):
def __init__(self, topic):
if not cfg.CONF.kafka.uri:
raise Exception('Kafka is not configured correctly! '
'Use configuration file to specify Kafka '
'uri, for example: '
'uri=192.168.1.191:9092')
self.uri = cfg.CONF.kafka.uri
self.topic = topic
self.group = cfg.CONF.kafka.group
self.wait_time = cfg.CONF.kafka.wait_time
self.async = cfg.CONF.kafka.async
self.ack_time = cfg.CONF.kafka.ack_time
self.max_retry = cfg.CONF.kafka.max_retry
self.auto_commit = cfg.CONF.kafka.auto_commit
self.compact = cfg.CONF.kafka.compact
self.partitions = cfg.CONF.kafka.partitions
self.drop_data = cfg.CONF.kafka.drop_data
self._client = None
self._producer = None
def _init_client(self, wait_time=None):
for i in range(self.max_retry):
try:
# if there is a client instance, but _init_client is called
# again, most likely the connection has gone stale, close that
# connection and reconnect.
if self._client:
self._client.close()
if not wait_time:
wait_time = self.wait_time
time.sleep(wait_time)
self._client = client.KafkaClient(self.uri)
# when a client is re-initialized, existing consumer should be
# reset as well.
self._producer = None
break
except common.KafkaUnavailableError:
LOG.error('Kafka server at %s is down.' % self.uri)
except common.LeaderNotAvailableError:
LOG.error('Kafka at %s has no leader available.' % self.uri)
except Exception:
LOG.error('Kafka at %s initialization failed.' % self.uri)
# Wait a bit and try again to get a client
time.sleep(self.wait_time)
def _init_producer(self):
try:
if not self._client:
self._init_client()
self._producer = producer.SimpleProducer(
self._client, async=self.async, ack_timeout=self.ack_time)
LOG.debug('Kafka SimpleProducer was created successfully.')
except Exception:
self._producer = None
LOG.exception('Kafka (%s) producer can not be created.' % self.uri)
def close(self):
if self._client:
self._producer = None
self._client.close()
def send_message(self, message):
try:
if not self._producer:
self._init_producer()
self._producer.send_messages(self.topic, message)
except (common.KafkaUnavailableError,
common.LeaderNotAvailableError):
self._client = None
LOG.exception('Error occurred while posting data to Kafka.')
raise exceptions.MessageQueueException()
except Exception:
LOG.exception('Unknown error.')
raise exceptions.MessageQueueException()