998f6afa53
On failure to publish, clear the topic metadata then retry, in case the IP Addresses have changed. This can occur when Monasca is run in Kubernetes and the Kafka pod is restarted. Restarting the Kafka pod can happen often enough the API should be able handle it without losing a message. Change-Id: If48971c40883b5be10adec947562cdda7e82d77c Story: 2001386 Task: 5963
76 lines
2.7 KiB
Python
76 lines
2.7 KiB
Python
# (C) Copyright 2015, 2017 Hewlett Packard Enterprise Development LP
|
|
#
|
|
# 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 time
|
|
|
|
import monasca_common.kafka_lib.client as kafka_client
|
|
import monasca_common.kafka_lib.producer as kafka_producer
|
|
|
|
log = logging.getLogger(__name__)
|
|
|
|
|
|
class KafkaProducer(object):
|
|
"""Adds messages to a kafka topic
|
|
|
|
"""
|
|
|
|
def __init__(self, url):
|
|
"""Init
|
|
|
|
url - kafka connection details
|
|
"""
|
|
self._kafka = kafka_client.KafkaClient(url)
|
|
self._producer = kafka_producer.KeyedProducer(
|
|
self._kafka,
|
|
async=False,
|
|
req_acks=kafka_producer.KeyedProducer.ACK_AFTER_LOCAL_WRITE,
|
|
ack_timeout=2000)
|
|
|
|
def publish(self, topic, messages, key=None):
|
|
"""Takes messages and puts them on the supplied kafka topic
|
|
|
|
"""
|
|
|
|
if not isinstance(messages, list):
|
|
messages = [messages]
|
|
|
|
first = True
|
|
success = False
|
|
while not success:
|
|
try:
|
|
if key is None:
|
|
key = int(time.time() * 1000)
|
|
self._producer.send_messages(topic, str(key), *messages)
|
|
success = True
|
|
except Exception:
|
|
if first:
|
|
# This is a warning because of all the other warning and
|
|
# error messages that are logged in this case. This way
|
|
# someone looking at the log file can see the retry
|
|
log.warn("Failed send on topic {}, clear metadata and retry"
|
|
.format(topic))
|
|
|
|
# If Kafka is running in Kubernetes, the cached metadata
|
|
# contains the IP Address of the Kafka pod. If the Kafka
|
|
# pod has restarted, the IP Address will have changed
|
|
# which would have caused the first publish to fail. So,
|
|
# clear the cached metadata and retry the publish
|
|
self._kafka.reset_topic_metadata(topic)
|
|
first = False
|
|
continue
|
|
log.exception('Error publishing to {} topic.'.format(topic))
|
|
raise
|