/usr/lib/python2.7/dist-packages/oslo_messaging/_drivers/impl_kafka.py is in python-oslo.messaging 5.35.0-0ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 | # Copyright (C) 2015 Cisco Systems, Inc.
#
# 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.
# Following code fixes 2 issues with kafka-python and
# The current release of eventlet (0.19.0) does not actually remove
# select.poll [1]. Because of kafka-python.selectors34 selects
# PollSelector instead of SelectSelector [2]. PollSelector relies on
# select.poll, which does not work when eventlet/greenlet is used. This
# bug in evenlet is fixed in the master branch [3], but there's no
# release of eventlet that includes this fix at this point.
import json
import threading
import kafka
from kafka.client_async import selectors
import kafka.errors
from oslo_log import log as logging
from oslo_utils import eventletutils
import tenacity
from oslo_messaging._drivers import base
from oslo_messaging._drivers import common as driver_common
from oslo_messaging._drivers.kafka_driver import kafka_options
from oslo_messaging._i18n import _LE
from oslo_messaging._i18n import _LW
from oslo_serialization import jsonutils
import logging as l
l.basicConfig(level=l.INFO)
l.getLogger("kafka").setLevel(l.WARN)
l.getLogger("stevedore").setLevel(l.WARN)
if eventletutils.is_monkey_patched('select'):
# monkeypatch the vendored SelectSelector._select like eventlet does
# https://github.com/eventlet/eventlet/blob/master/eventlet/green/selectors.py#L32
from eventlet.green import select
selectors.SelectSelector._select = staticmethod(select.select)
# Force to use the select selectors
KAFKA_SELECTOR = selectors.SelectSelector
else:
KAFKA_SELECTOR = selectors.DefaultSelector
LOG = logging.getLogger(__name__)
def unpack_message(msg):
context = {}
message = None
msg = json.loads(msg)
message = driver_common.deserialize_msg(msg)
context = message['_context']
del message['_context']
return context, message
def pack_message(ctxt, msg):
"""Pack context into msg."""
if isinstance(ctxt, dict):
context_d = ctxt
else:
context_d = ctxt.to_dict()
msg['_context'] = context_d
msg = driver_common.serialize_msg(msg)
return msg
def concat(sep, items):
return sep.join(filter(bool, items))
def target_to_topic(target, priority=None, vhost=None):
"""Convert target into topic string
:param target: Message destination target
:type target: oslo_messaging.Target
:param priority: Notification priority
:type priority: string
:param priority: Notification vhost
:type priority: string
"""
return concat(".", [target.topic, priority, vhost])
def retry_on_retriable_kafka_error(exc):
return (isinstance(exc, kafka.errors.KafkaError) and exc.retriable)
def with_reconnect(retries=None):
def decorator(func):
@tenacity.retry(
retry=tenacity.retry_if_exception(retry_on_retriable_kafka_error),
wait=tenacity.wait_fixed(1),
stop=tenacity.stop_after_attempt(retries),
reraise=True
)
def wrapper(*args, **kwargs):
return func(*args, **kwargs)
return wrapper
return decorator
class Connection(object):
def __init__(self, conf, url):
self.conf = conf
self.url = url
self.virtual_host = url.virtual_host
self._parse_url()
def _parse_url(self):
driver_conf = self.conf.oslo_messaging_kafka
self.hostaddrs = []
for host in self.url.hosts:
if host.hostname:
self.hostaddrs.append("%s:%s" % (
host.hostname,
host.port or driver_conf.kafka_default_port))
if not self.hostaddrs:
self.hostaddrs.append("%s:%s" % (driver_conf.kafka_default_host,
driver_conf.kafka_default_port))
def reset(self):
"""Reset a connection so it can be used again."""
pass
class ConsumerConnection(Connection):
def __init__(self, conf, url):
super(ConsumerConnection, self).__init__(conf, url)
driver_conf = self.conf.oslo_messaging_kafka
self.consumer = None
self.consumer_timeout = driver_conf.kafka_consumer_timeout
self.max_fetch_bytes = driver_conf.kafka_max_fetch_bytes
self.group_id = driver_conf.consumer_group
self._consume_loop_stopped = False
@with_reconnect()
def _poll_messages(self, timeout):
messages = self.consumer.poll(timeout * 1000.0)
messages = [record.value
for records in messages.values() if records
for record in records]
if not messages:
# NOTE(sileht): really ? you return payload but no messages...
# simulate timeout to consume message again
raise kafka.errors.ConsumerTimeout()
return messages
def consume(self, timeout=None):
"""Receive up to 'max_fetch_messages' messages.
:param timeout: poll timeout in seconds
"""
def _raise_timeout(exc):
raise driver_common.Timeout(str(exc))
timer = driver_common.DecayingTimer(duration=timeout)
timer.start()
poll_timeout = (self.consumer_timeout if timeout is None
else min(timeout, self.consumer_timeout))
while True:
if self._consume_loop_stopped:
return
try:
return self._poll_messages(poll_timeout)
except kafka.errors.ConsumerTimeout as exc:
poll_timeout = timer.check_return(
_raise_timeout, exc, maximum=self.consumer_timeout)
except Exception:
LOG.exception(_LE("Failed to consume messages"))
return
def stop_consuming(self):
self._consume_loop_stopped = True
def close(self):
if self.consumer:
self.consumer.close()
self.consumer = None
@with_reconnect()
def declare_topic_consumer(self, topics, group=None):
# TODO(Support for manual/auto_commit functionality)
# When auto_commit is False, consumer can manually notify
# the completion of the subscription.
# Currently we don't support for non auto commit option
self.consumer = kafka.KafkaConsumer(
*topics, group_id=(group or self.group_id),
bootstrap_servers=self.hostaddrs,
max_partition_fetch_bytes=self.max_fetch_bytes,
selector=KAFKA_SELECTOR
)
class ProducerConnection(Connection):
def __init__(self, conf, url):
super(ProducerConnection, self).__init__(conf, url)
driver_conf = self.conf.oslo_messaging_kafka
self.batch_size = driver_conf.producer_batch_size
self.linger_ms = driver_conf.producer_batch_timeout * 1000
self.producer = None
self.producer_lock = threading.Lock()
def notify_send(self, topic, ctxt, msg, retry):
"""Send messages to Kafka broker.
:param topic: String of the topic
:param ctxt: context for the messages
:param msg: messages for publishing
:param retry: the number of retry
"""
retry = retry if retry >= 0 else None
message = pack_message(ctxt, msg)
message = jsonutils.dumps(message)
@with_reconnect(retries=retry)
def wrapped_with_reconnect():
self._ensure_producer()
# NOTE(sileht): This returns a future, we can use get()
# if we want to block like other driver
future = self.producer.send(topic, message)
future.get()
try:
wrapped_with_reconnect()
except Exception:
# NOTE(sileht): if something goes wrong close the producer
# connection
self._close_producer()
raise
def close(self):
self._close_producer()
def _close_producer(self):
with self.producer_lock:
if self.producer:
self.producer.close()
self.producer = None
def _ensure_producer(self):
if self.producer:
return
with self.producer_lock:
if self.producer:
return
self.producer = kafka.KafkaProducer(
bootstrap_servers=self.hostaddrs,
linger_ms=self.linger_ms,
batch_size=self.batch_size,
selector=KAFKA_SELECTOR)
class OsloKafkaMessage(base.RpcIncomingMessage):
def __init__(self, ctxt, message):
super(OsloKafkaMessage, self).__init__(ctxt, message)
def requeue(self):
LOG.warning(_LW("requeue is not supported"))
def reply(self, reply=None, failure=None):
LOG.warning(_LW("reply is not supported"))
class KafkaListener(base.PollStyleListener):
def __init__(self, conn):
super(KafkaListener, self).__init__()
self._stopped = threading.Event()
self.conn = conn
self.incoming_queue = []
# FIXME(sileht): We do a first poll to ensure we topics are created
# This is a workaround mainly for functional tests, in real life
# this is fine if topics are not created synchroneously
self.poll(5)
@base.batch_poll_helper
def poll(self, timeout=None):
while not self._stopped.is_set():
if self.incoming_queue:
return self.incoming_queue.pop(0)
try:
messages = self.conn.consume(timeout=timeout) or []
for message in messages:
msg = OsloKafkaMessage(*unpack_message(message))
self.incoming_queue.append(msg)
except driver_common.Timeout:
return None
def stop(self):
self._stopped.set()
self.conn.stop_consuming()
def cleanup(self):
self.conn.close()
class KafkaDriver(base.BaseDriver):
"""Note: Current implementation of this driver is experimental.
We will have functional and/or integrated testing enabled for this driver.
"""
def __init__(self, conf, url, default_exchange=None,
allowed_remote_exmods=None):
conf = kafka_options.register_opts(conf, url)
super(KafkaDriver, self).__init__(
conf, url, default_exchange, allowed_remote_exmods)
self.listeners = []
self.virtual_host = url.virtual_host
self.pconn = ProducerConnection(conf, url)
def cleanup(self):
self.pconn.close()
for c in self.listeners:
c.close()
self.listeners = []
def send(self, target, ctxt, message, wait_for_reply=None, timeout=None,
retry=None):
raise NotImplementedError(
'The RPC implementation for Kafka is not implemented')
def send_notification(self, target, ctxt, message, version, retry=None):
"""Send notification to Kafka brokers
:param target: Message destination target
:type target: oslo_messaging.Target
:param ctxt: Message context
:type ctxt: dict
:param message: Message payload to pass
:type message: dict
:param version: Messaging API version (currently not used)
:type version: str
:param retry: an optional default kafka consumer retries configuration
None means to retry forever
0 means no retry
N means N retries
:type retry: int
"""
self.pconn.notify_send(target_to_topic(target,
vhost=self.virtual_host),
ctxt, message, retry)
def listen(self, target, batch_size, batch_timeout):
raise NotImplementedError(
'The RPC implementation for Kafka is not implemented')
def listen_for_notifications(self, targets_and_priorities, pool,
batch_size, batch_timeout):
"""Listen to a specified list of targets on Kafka brokers
:param targets_and_priorities: List of pairs (target, priority)
priority is not used for kafka driver
target.exchange_target.topic is used as
a kafka topic
:type targets_and_priorities: list
:param pool: consumer group of Kafka consumers
:type pool: string
"""
conn = ConsumerConnection(self.conf, self._url)
topics = set()
for target, priority in targets_and_priorities:
topics.add(target_to_topic(target, priority))
conn.declare_topic_consumer(topics, pool)
listener = KafkaListener(conn)
return base.PollStyleListenerAdapter(listener, batch_size,
batch_timeout)
|