Kafka消费者调查获取多个记录

Question

我已经使用以下设置实现了使用者。

allow.auto.create.topics = true
auto.commit.interval.ms = 1000
auto.offset.reset = latest
bootstrap.servers = [confluent-kafka-cp-kafka-headless:9092]
check.crcs = true
client.dns.lookup = default
client.id =
client.rack =
connections.max.idle.ms = 540000
default.api.timeout.ms = 60000
enable.auto.commit = false
exclude.internal.topics = true
fetch.max.bytes = 52428800
fetch.max.wait.ms = 500
fetch.min.bytes = 1
group.id = kafka-consumer
group.instance.id = null
heartbeat.interval.ms = 3000
interceptor.classes = []
internal.leave.group.on.close = true
isolation.level = read_uncommitted
key.deserializer = class org.apache.kafka.common.serialization.StringDeserializer
max.partition.fetch.bytes = 1048576
max.poll.interval.ms = 300000
max.poll.records = 200
metadata.max.age.ms = 300000
metric.reporters = []
metrics.num.samples = 2
metrics.recording.level = INFO
metrics.sample.window.ms = 30000
partition.assignment.strategy = [class org.apache.kafka.clients.consumer.RangeAssignor]
receive.buffer.bytes = 65536
reconnect.backoff.max.ms = 1000
reconnect.backoff.ms = 50
request.timeout.ms = 30000
retry.backoff.ms = 100
sasl.client.callback.handler.class = null
sasl.jaas.config = null
sasl.kerberos.kinit.cmd = /usr/bin/kinit
sasl.kerberos.min.time.before.relogin = 60000
sasl.kerberos.service.name = null
sasl.kerberos.ticket.renew.jitter = 0.05
sasl.kerberos.ticket.renew.window.factor = 0.8
sasl.login.callback.handler.class = null
sasl.login.class = null
sasl.login.refresh.buffer.seconds = 300
sasl.login.refresh.min.period.seconds = 60
sasl.login.refresh.window.factor = 0.8
sasl.login.refresh.window.jitter = 0.05
sasl.mechanism = GSSAPI
security.protocol = PLAINTEXT
security.providers = null
send.buffer.bytes = 131072
session.timeout.ms = 30000
ssl.cipher.suites = null
ssl.enabled.protocols = [TLSv1.2, TLSv1.1, TLSv1]
ssl.endpoint.identification.algorithm = https
ssl.key.password = null
ssl.keymanager.algorithm = SunX509
ssl.keystore.location = null
ssl.keystore.password = null
ssl.keystore.type = JKS
ssl.protocol = TLS
ssl.provider = null
ssl.secure.random.implementation = null
ssl.trustmanager.algorithm = PKIX
ssl.truststore.location = null
ssl.truststore.password = null
ssl.truststore.type = JKS
value.deserializer = class org.apache.kafka.common.serialization.StringDeserializer

在我的代码中，我尝试在每次轮询后打印记录大小，如下所示-

protected static final int MAX_WAIT = 60;
while (true) {
    ConsumerRecords<String, String> records = consumer.poll(Duration.ofMinutes(MAX_WAIT));
    sysout(records.count());
}

但是我看到record.count =1。我希望它能够从单个poll（）而不是单个记录。

我的事件如下-

{"event": {"sensor": "sensorA", "current": 33, "etime": "1588375763429"}}}

我的制作人正在连续运行。我不确定配置设置是否正确或生产者是否没有提供足够的数据供消费者在一次民意调查中获取。

注意-我是kafka的新手

关于，Edi

Answer 1

假设您的生产者发送了足够的记录，请尝试增加以下参数：

fetch.max.wait.ms = 60000
fetch.min.bytes = 1024000  

现在，使用者应先等待更高的最小字节数，然后再从Kafka提取记录。 
如果解决您的问题，我将提供有关这些更改的进一步说明。