我有一个spring cloud stream kafka流应用程序,它读取一个主题(事件)并执行一个简单的处理:
@Configuration
class EventKStreamConfiguration {
private val logger = LoggerFactory.getLogger(javaClass)
@StreamListener
fun process(@Input("event") eventStream: KStream<String, EventReceived>) {
eventStream.foreach { key, value ->
logger.info("--------> Processing Event {}", value)
// Save in DB
}
}
}
此应用程序使用来自confluent cloud的kafka环境,其事件主题具有6个分区。完整配置为:
spring:
application:
name: events-processor
cloud:
stream:
schema-registry-client:
endpoint: ${schema-registry-url:http://localhost:8081}
kafka:
streams:
binder:
brokers: ${kafka-brokers:localhost}
configuration:
application:
id: ${spring.application.name}
default:
key:
serde: org.apache.kafka.common.serialization.Serdes$StringSerde
schema:
registry:
url: ${spring.cloud.stream.schema-registry-client.endpoint}
value:
subject:
name:
strategy: io.confluent.kafka.serializers.subject.RecordNameStrategy
processing:
guarantee: exactly_once
bindings:
event:
consumer:
valueSerde: io.confluent.kafka.streams.serdes.avro.SpecificAvroSerde
bindings:
event:
destination: event
data:
mongodb:
uri: ${mongodb-uri:mongodb://localhost/test}
server:
port: 8085
logging:
level:
org.springframework.kafka.config: debug
---
spring:
profiles: confluent-cloud
cloud:
stream:
kafka:
streams:
binder:
autoCreateTopics: false
configuration:
retry:
backoff:
ms: 500
security:
protocol: SASL_SSL
sasl:
mechanism: PLAIN
jaas:
config: xxx
basic:
auth:
credentials:
source: USER_INFO
schema:
registry:
basic:
auth:
user:
info: yyy
kstream正在正确处理消息。如果我重新启动应用程序,它们不会被重新处理。注意:我不希望他们被重新处理,所以这种行为是可以的。
但是,启动日志显示了一些奇怪的信息:
首先,它显示还原使用者客户端的创建。自动偏移复位无:
2019-07-19 10:20:17.120 INFO 82473 --- [ main] o.a.k.s.p.internals.StreamThread : stream-thread [events-processor-9a8069c4-3fb6-4d76-a207-efbbadd52b8f-StreamThread-1] Creating restore consumer client
2019-07-19 10:20:17.123 INFO 82473 --- [ main] o.a.k.clients.consumer.ConsumerConfig : ConsumerConfig values:
auto.commit.interval.ms = 5000
auto.offset.reset = none
然后创建一个具有自动偏移重置功能的客户机。
2019-07-19 10:20:17.235 INFO 82473 --- [ main] o.a.k.s.p.internals.StreamThread : stream-thread [events-processor-9a8069c4-3fb6-4d76-a207-efbbadd52b8f-StreamThread-1] Creating consumer client
2019-07-19 10:20:17.241 INFO 82473 --- [ main] o.a.k.clients.consumer.ConsumerConfig : ConsumerConfig values:
auto.commit.interval.ms = 5000
auto.offset.reset = earliest
启动日志的最后跟踪显示偏移量重置为0。每次重新启动应用程序时都会发生这种情况:
2019-07-19 10:20:31.577 INFO 82473 --- [-StreamThread-1] o.a.k.s.p.internals.StreamThread : stream-thread [events-processor-9a8069c4-3fb6-4d76-a207-efbbadd52b8f-StreamThread-1] State transition from PARTITIONS_ASSIGNED to RUNNING
2019-07-19 10:20:31.578 INFO 82473 --- [-StreamThread-1] org.apache.kafka.streams.KafkaStreams : stream-client [events-processor-9a8069c4-3fb6-4d76-a207-efbbadd52b8f] State transition from REBALANCING to RUNNING
2019-07-19 10:20:31.669 INFO 82473 --- [events-processor] o.a.k.c.consumer.internals.Fetcher : [Consumer clientId=events-processor-9a8069c4-3fb6-4d76-a207-efbbadd52b8f-StreamThread-1-consumer, groupId=events-processor] Resetting offset for partition event-3 to offset 0.
2019-07-19 10:20:31.669 INFO 82473 --- [events-processor] o.a.k.c.consumer.internals.Fetcher : [Consumer clientId=events-processor-9a8069c4-3fb6-4d76-a207-efbbadd52b8f-StreamThread-1-consumer, groupId=events-processor] Resetting offset for partition event-0 to offset 0.
2019-07-19 10:20:31.669 INFO 82473 --- [events-processor] o.a.k.c.consumer.internals.Fetcher : [Consumer clientId=events-processor-9a8069c4-3fb6-4d76-a207-efbbadd52b8f-StreamThread-1-consumer, groupId=events-processor] Resetting offset for partition event-1 to offset 0.
2019-07-19 10:20:31.669 INFO 82473 --- [events-processor] o.a.k.c.consumer.internals.Fetcher : [Consumer clientId=events-processor-9a8069c4-3fb6-4d76-a207-efbbadd52b8f-StreamThread-1-consumer, groupId=events-processor] Resetting offset for partition event-5 to offset 0.
2019-07-19 10:20:31.670 INFO 82473 --- [events-processor] o.a.k.c.consumer.internals.Fetcher : [Consumer clientId=events-processor-9a8069c4-3fb6-4d76-a207-efbbadd52b8f-StreamThread-1-consumer, groupId=events-processor] Resetting offset for partition event-4 to offset 0.
为什么配置了两个消费者?
为什么第二个有 auto.offset.reset = earliest
当我没有显式地配置它并且Kafka默认值是最新的?
我想要默认的(auto.offset.reset=latest)行为,它看起来工作正常。然而,这与我在日志中看到的不矛盾吗?
更新:
我想把第三个问题改成这样:为什么日志显示分区在每次重新启动时都被重置为0,尽管如此,没有消息被重新传递到kstream?
更新2:
我已经简化了这个场景,这次使用了一个本地kafka流应用程序。这种现象与 Spring 云流的观测结果完全相同。然而,检查消费者组和分区我发现这是有意义的。
K流:
fun main() {
val props = Properties()
props[StreamsConfig.APPLICATION_ID_CONFIG] = "streams-wordcount"
props[StreamsConfig.BOOTSTRAP_SERVERS_CONFIG] = "localhost:9092"
props[StreamsConfig.CACHE_MAX_BYTES_BUFFERING_CONFIG] = 0
props[StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG] = Serdes.String().javaClass.name
props[StreamsConfig.DEFAULT_VALUE_SERDE_CLASS_CONFIG] = Serdes.String().javaClass.name
val builder = StreamsBuilder()
val source = builder.stream<String, String>("streams-plaintext-input")
source.foreach { key, value -> println("$key $value") }
val streams = KafkaStreams(builder.build(), props)
val latch = CountDownLatch(1)
// attach shutdown handler to catch control-c
Runtime.getRuntime().addShutdownHook(object : Thread("streams-wordcount-shutdown-hook") {
override fun run() {
streams.close()
latch.countDown()
}
})
try {
streams.start()
latch.await()
} catch (e: Throwable) {
exitProcess(1)
}
exitProcess(0)
}
这就是我所看到的:
1) 如果主题为空,则启动将显示所有分区重置为偏移量0:
07:55:03.885 [streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-2 to offset 0.
07:55:03.886 [streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-3 to offset 0.
07:55:03.886 [streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-0 to offset 0.
07:55:03.886 [streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-1 to offset 0.
07:55:03.886 [streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-4 to offset 0.
07:55:03.886 [streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-3549a54e-49db-4490-bd9f-7156e972021a-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-5 to offset 0
2) 我在主题中放了一条消息并检查了消费者组,看到记录在分区4中:
TOPIC PARTITION CURRENT-OFFSET LOG-END-OFFSET LAG CONSUMER-ID HOST CLIENT-ID
streams-plaintext-input 0 - 0 - streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer-905a307a-4c49-4d8b-ac2e-5525ba2e8a8e /127.0.0.1 streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer
streams-plaintext-input 5 - 0 - streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer-905a307a-4c49-4d8b-ac2e-5525ba2e8a8e /127.0.0.1 streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer
streams-plaintext-input 1 - 0 - streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer-905a307a-4c49-4d8b-ac2e-5525ba2e8a8e /127.0.0.1 streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer
streams-plaintext-input 2 - 0 - streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer-905a307a-4c49-4d8b-ac2e-5525ba2e8a8e /127.0.0.1 streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer
streams-plaintext-input 3 - 0 - streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer-905a307a-4c49-4d8b-ac2e-5525ba2e8a8e /127.0.0.1 streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer
streams-plaintext-input 4 1 1 0 streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer-905a307a-4c49-4d8b-ac2e-5525ba2e8a8e /127.0.0.1 streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer
3) 我重新启动应用程序。现在重置只影响空分区(0、1、2、3、5):
07:57:39.477 [streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-2 to offset 0.
07:57:39.478 [streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-3 to offset 0.
07:57:39.478 [streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-0 to offset 0.
07:57:39.479 [streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-1 to offset 0.
07:57:39.479 [streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-b1565eca-7d80-4550-97d2-e78ead62a840-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-5 to offset 0.
4) 我插入另一条消息,检查使用者组状态,同样的情况发生了:记录在分区2中,当重新启动应用程序时,它只重置空分区(0、1、3、5):
TOPIC PARTITION CURRENT-OFFSET LOG-END-OFFSET LAG CONSUMER-ID HOST CLIENT-ID
streams-plaintext-input 0 - 0 - streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer-cb04e2bd-598f-455f-b913-1370b4144dd6 /127.0.0.1 streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer
streams-plaintext-input 5 - 0 - streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer-cb04e2bd-598f-455f-b913-1370b4144dd6 /127.0.0.1 streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer
streams-plaintext-input 1 - 0 - streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer-cb04e2bd-598f-455f-b913-1370b4144dd6 /127.0.0.1 streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer
streams-plaintext-input 2 1 1 0 streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer-cb04e2bd-598f-455f-b913-1370b4144dd6 /127.0.0.1 streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer
streams-plaintext-input 3 - 0 - streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer-cb04e2bd-598f-455f-b913-1370b4144dd6 /127.0.0.1 streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer
streams-plaintext-input 4 1 1 0 streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer-cb04e2bd-598f-455f-b913-1370b4144dd6 /127.0.0.1 streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer
08:00:42.313 [streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-3 to offset 0.
08:00:42.314 [streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-0 to offset 0.
08:00:42.314 [streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-1 to offset 0.
08:00:42.314 [streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1] INFO org.apache.kafka.clients.consumer.internals.Fetcher - [Consumer clientId=streams-wordcount-addb08ed-62ce-47f9-a446-f2ee0592c53d-StreamThread-1-consumer, groupId=streams-wordcount] Resetting offset for partition streams-plaintext-input-5 to offset 0.
1条答案
按热度按时间bttbmeg01#
为什么配置了两个消费者?
Restore Consumer Client
是容错和状态管理的专用使用者。它负责从changelog主题恢复状态。它与应用程序使用者客户端分开显示。您可以在此处找到更多信息:https://docs.confluent.io/current/streams/monitoring.html#kafka-还原使用者客户端id为什么第二个设置auto.offset.reset=earliest,而我没有显式配置它,并且kafka默认值是最新的?
你是对的,
auto.offset.reset
默认值为latest
在Kafka消费。但在SpringCloudStream中,消费者的默认值startOffset
是earliest
. 因此它显示earliest
第二消费者。也取决于spring.cloud.stream.bindings.<channelName>.group
结合。如果显式设置,则startOffset
设置为earliest
,否则设置为latest
为了anonymous
消费者。参考资料:Spring Cloud流Kafka消费物业
我想要默认的(auto.offset.reset=latest)行为,它看起来工作正常。然而,这与我在日志中看到的不矛盾吗?
万一
anonymous
使用者组,的默认值startOffset
将latest
.