-
Notifications
You must be signed in to change notification settings - Fork 11
/
sink.py
296 lines (255 loc) · 10.1 KB
/
sink.py
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
from collections import namedtuple
from struct import (pack, unpack)
import time
from ..compat import BytesIO
from ..dispatch import MessageDispatcher
from ..loadbalancer.serverset import StaticServerSetProvider
from ..loadbalancer.zookeeper import Member
from ..message import (
MethodCallMessage,
MethodReturnMessage
)
from ..mux.sink import MuxSocketTransportSink
from ..sink import (
ClientMessageSink,
SinkProperties,
SinkProvider,
SinkRole,
)
from ..thrift.sink import SocketTransportSinkProvider
from .protocol import (
BrokerMetadata,
ErrorCode,
KafkaError,
KafkaProtocol,
MessageHelper,
NoBrokerForTopicException,
)
KafkaEndpoint = namedtuple("KafkaEndpoint", "host port partition_id")
KafkaEndpoint.__str__ = lambda k: '%s:%d' % (k.host, k.port)
class TopicState(object):
def __init__(self, topic_name, lb, brokers, open_ar):
self.topic_name = topic_name
self.lb = lb
self.brokers = brokers
self.last_refreshed = time.time()
self.open_ar = open_ar
class KafkaTransportSink(MuxSocketTransportSink):
CLIENT_ID = 'scales'
def _CheckInitialConnection(self):
pass
def _OnTimeout(self, tag):
pass
def _BuildHeader(self, tag, msg_type, data_len):
header = pack(
'!ihhih%ds' % len(self.CLIENT_ID),
2 + 2 + 4 + 2 + len(self.CLIENT_ID) + data_len,
msg_type,
0,
tag,
len(self.CLIENT_ID),
self.CLIENT_ID
)
return header
def _ProcessReply(self, stream):
tag, = unpack('!i', stream.read(4))
self._ProcessTaggedReply(tag, stream)
class KafkaRouterSink(ClientMessageSink):
_RETRY_KEY = "__KafkaRetries"
_BOOTSTRAP_SUFFIX = "-bootstrap"
def __init__(self, next_provider, sink_properties, global_properties):
self._metadata = None
self._topics = {}
self._next_provider = next_provider
self._global_properties = global_properties
self._label = global_properties['label']
self._refresh_rate = sink_properties.refresh_rate
self._refresh_ar = None
self._bootstrap_servers = set()
self._bootstrap_lb = self._CreateBootstrapLoadBalancer(
sink_properties.server_set_provider)
super(KafkaRouterSink, self).__init__()
def _CreateBootstrapLoadBalancer(self, broker_provider):
"""Create a load balancer used to bootstrap the cluster.
Args:
broker_provider: A ServerSetProvider that contains at least one kafka
broker.
Returns:
A load balancer that can be used to bootstrap the kafka client.
"""
brokers = []
broker_provider.Initialize(None, None)
for bs in broker_provider.GetServers():
ep = bs.service_endpoint
brokers.append((-1, BrokerMetadata(-1, ep.host, ep.port)))
self._bootstrap_servers = set([(b.host, b.port) for _, b in brokers])
return self._CreateBrokerLoadBalancer(brokers, self._BOOTSTRAP_SUFFIX)
def _RefreshMetadataAsync(self):
"""Asynchronously refreshes the kafka cluster metadata.
Returns:
An AsyncResult representing the refresh operation.
"""
if not self._refresh_ar:
self._refresh_ar = self._bootstrap_lb.Open().ContinueWith(
lambda ar: MessageDispatcher.StaticDispatchMessage(
self._bootstrap_lb,
None,
0,
0,
MethodCallMessage(None, '__metadata', [], {}))
).Unwrap()
return self._refresh_ar
def _CreateBrokerLoadBalancer(self, brokers, service_suffix):
"""Create a load balancer for a set of brokers.
Args:
brokers - A list of (partition_id, BrokerMetadata) tuples.
service_suffix - An optional suffix to add the to generated service.
Returns:
A new load balancer sink populated with the brokers passed in.
"""
members = [
Member(b.nodeId, KafkaEndpoint(b.host, b.port, partition_id), {}, b.nodeId, 'ALIVE')
for partition_id, b in brokers
]
ssp = StaticServerSetProvider(members)
balancer = self._next_provider.Clone(server_set_provider=ssp)
return balancer.CreateSink({ SinkProperties.Label: self._label + (service_suffix or '') })
def _RebuildTopicLoadBalancers(self, broker_metadata, requested_topic_name):
"""Creates a new set of load balancers for all topics. Each load balancer
consists of the leaders for all partitions in a topic.
Args:
broker_metadata - A MetadataResponse object.
topic_name - The topic to refresh
"""
brokers = broker_metadata.brokers
new_topics = {}
old_lbs_to_close = []
seen_new_topics = set()
for topic_name, t in broker_metadata.topics.items():
partition_leaders = set((p.partition_id, p.leader)
for p in t.values() if p.leader != -1)
topic_brokers = set((partition_id, brokers[broker])
for partition_id, broker in partition_leaders)
topic_state = self._topics.get(topic_name)
if topic_state and topic_state.brokers == topic_brokers:
topic_state.last_refreshed = time.time()
elif topic_name == requested_topic_name:
if topic_state:
old_lbs_to_close.append(topic_state.lb)
lb = self._CreateBrokerLoadBalancer(topic_brokers, None)
open_ar = lb.Open()
topic_state = TopicState(topic_name, lb, topic_brokers, open_ar)
else:
seen_new_topics.add(topic_name)
if topic_state:
new_topics[topic_name] = topic_state
self._topics = new_topics
for lb in old_lbs_to_close:
lb.Close()
new_bootstrap_keys = set((b.host, b.port) for b in brokers.values())
if new_bootstrap_keys != self._bootstrap_servers:
new_bootstrap = self._CreateBrokerLoadBalancer(brokers.items(), self._BOOTSTRAP_SUFFIX)
old_bootstrap = self._bootstrap_lb
self._bootstrap_lb = new_bootstrap
old_bootstrap.Close()
def _GetTopic(self, topic):
return self._topics.get(topic)
def _RefreshBrokersAndRetry(self, topic_name, sink_stack, msg):
topic_info = self._GetTopic(topic_name)
if topic_info and (
time.time() - topic_info.last_refreshed < self._refresh_rate):
# We've already tried to refresh within the refresh rate, just send it
self._AsyncProcessRequestToTopic(sink_stack, msg, topic_info)
return
refresh_ar = self._RefreshMetadataAsync()
def _on_refresh_complete(ar):
self._refresh_ar = None
if ar.exception:
sink_stack.AsyncProcessResponseMessage(
MethodReturnMessage(error=ar.exception))
else:
try:
# Rebuild
self._RebuildTopicLoadBalancers(ar.value, topic_name)
# Retry
topic, _, _ = MessageHelper.GetPutArgs(msg)
topic_info = self._GetTopic(topic)
if not topic_info:
sink_stack.AsyncProcessResponseMessage(
MethodReturnMessage(error=NoBrokerForTopicException("No broker for topic %s" % topic))
)
else:
# We're in the gevent hub here, move to a new greenlet to do the retry.
self._AsyncProcessRequestToTopic(sink_stack, msg, topic_info)
except Exception as ex:
sink_stack.AsyncProcessResponseMessage(MethodReturnMessage(error=ex))
refresh_ar.ContinueWith(_on_refresh_complete, False)
def _AsyncProcessRequestToTopic(self, sink_stack, msg, topic_info):
def _send_msg(_):
sink_stack.Push(self, (msg, topic_info.topic_name))
topic_info.lb.AsyncProcessRequest(sink_stack, msg, None, {})
if not topic_info.open_ar:
topic_info.open_ar = topic_info.lb.Open()
topic_info.open_ar.ContinueWith(_send_msg, False)
def AsyncProcessRequest(self, sink_stack, msg, stream, headers):
topic, _, _ = MessageHelper.GetPutArgs(msg)
topic_info = self._GetTopic(topic)
if not topic_info:
self._RefreshBrokersAndRetry(topic, sink_stack, msg)
else:
self._AsyncProcessRequestToTopic(sink_stack, msg, topic_info)
def AsyncProcessResponse(self, sink_stack, context, stream, msg):
req_msg, topic_name = context
num_retries = req_msg.properties.get(self._RETRY_KEY, 0)
if msg.return_value:
if len(msg.return_value) != 1:
sink_stack.AsyncProcessResponseMessage(
MethodReturnMessage(error=Exception('Invalid response from kafka: unexpected return value')))
else:
err_code = msg.return_value[0].error
if err_code == ErrorCode.NoError:
sink_stack.AsyncProcessResponseMessage(msg)
elif err_code in ErrorCode.ReloadMetadataCodes and num_retries == 0:
# Refresh metadata and retry
req_msg.properties[self._RETRY_KEY] = 1
self._RefreshBrokersAndRetry(topic_name, sink_stack, req_msg)
else:
err_msg = MethodReturnMessage(error=KafkaError(
'Kafka broker returned error %d' % err_code, err_code))
sink_stack.AsyncProcessResponseMessage(err_msg)
else:
# An exception occured, retry once
self._RefreshBrokersAndRetry(topic_name, sink_stack, req_msg)
class KafkaSerializerSink(ClientMessageSink):
def __init__(self, next_provider, sink_properties, global_properties):
super(KafkaSerializerSink, self).__init__()
self._serializer = KafkaProtocol()
self.next_sink = next_provider.CreateSink(global_properties)
def AsyncProcessRequest(self, sink_stack, msg, stream, headers):
buf = BytesIO()
headers = {}
try:
ctx = self._serializer.SerializeMessage(msg, buf, headers)
except Exception as ex:
msg = MethodReturnMessage(error=ex)
sink_stack.AsyncProcessResponseMessage(msg)
return
sink_stack.Push(self, ctx)
self.next_sink.AsyncProcessRequest(sink_stack, msg, buf, headers)
def AsyncProcessResponse(self, sink_stack, context, stream, msg):
if msg:
sink_stack.AsyncProcessResponseMessage(msg)
else:
try:
msg = self._serializer.DeserializeMessage(stream, context)
except Exception as ex:
msg = MethodReturnMessage(error=ex)
sink_stack.AsyncProcessResponseMessage(msg)
KafkaRouterSink.Builder = SinkProvider(
KafkaRouterSink,
SinkRole.LoadBalancer,
server_set_provider = None,
refresh_rate = 10
)
KafkaSerializerSink.Builder = SinkProvider(KafkaSerializerSink)
KafkaTransportSink.Builder = SocketTransportSinkProvider(KafkaTransportSink)