kafka集群及与springboot集成

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linux搭建,kafkao3节点虚拟机为CentOS6,ip为192.168.1.128，192.168.1.129和192.168.1.130，域名分别为master,worker1,worker2

1. 集群

  #192.168.1.128
  [root@master local]# cd /home/gilbert/app/rar/
  [root@master rar]# tar zxvf kafka_2.10-0.10.2.0.tgz
  [root@master rar]# mv kafka_2.10-0.10.2.0 /home/gilbert/app/kafka
  ​

配置文件路径：kafka/config/server.properties

修改配置文件

  
[root@master config]# more server.properties 
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You 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.
​
# see kafka.server.KafkaConfig for additional details and defaults
​
############################# Server Basics #############################
​
# The id of the broker. This must be set to a unique integer for each broker.
##每一个broker在集群中的唯一标示，要求是正数。在改变IP地址，不改变broker.id的话不会影响consumers
broker.id=0
​
# Switch to enable topic deletion or not, default value is false
## 是否允许自动创建topic ，若是false，就需要通过命令创建topic
delete.topic.enable=true
​
############################# Socket Server Settings #############################
​
# The address the socket server listens on. It will get the value returned from 
# java.net.InetAddress.getCanonicalHostName() if not configured.
#   FORMAT:
#     listeners = listener_name://host_name:port
#   EXAMPLE:
#     listeners = PLAINTEXT://your.host.name:9092
#listeners=PLAINTEXT://:9092
##提供给客户端响应的端口
port=9092
host.name=192.168.1.128
​
# Hostname and port the broker will advertise to producers and consumers. If not set, 
# it uses the value for "listeners" if configured.  Otherwise, it will use the value
# returned from java.net.InetAddress.getCanonicalHostName().
#advertised.listeners=PLAINTEXT://your.host.name:9092
​
# Maps listener names to security protocols, the default is for them to be the same. See the config documentation for more details
#listener.security.protocol.map=PLAINTEXT:PLAINTEXT,SSL:SSL,SASL_PLAINTEXT:SASL_PLAINTEXT,SASL_SSL:SASL_SSL
​
# The number of threads handling network requests
## broker 处理消息的最大线程数，一般情况下不需要去修改
num.network.threads=3
​
# The number of threads doing disk I/O
## broker处理磁盘IO 的线程数 ，数值应该大于你的硬盘数
num.io.threads=8
​
# The send buffer (SO_SNDBUF) used by the socket server
## socket的发送缓冲区，socket的调优参数SO_SNDBUFF
socket.send.buffer.bytes=102400
​
# The receive buffer (SO_RCVBUF) used by the socket server
## socket的接受缓冲区，socket的调优参数SO_RCVBUFF
socket.receive.buffer.bytes=102400
​
# The maximum size of a request that the socket server will accept (protection against OOM)
## socket请求的最大数值，防止serverOOM，message.max.bytes必然要小于socket.request.max.bytes，会被topic创建时的指定参数覆盖
socket.request.max.bytes=104857600
​
​
############################# Log Basics #############################
​
# A comma seperated list of directories under which to store log files
##kafka数据的存放地址，多个地址的话用逗号分割/data/kafka-logs-1，/data/kafka-logs-2
log.dirs=/tmp/kafka-logs
​
# The default number of log partitions per topic. More partitions allow greater
# parallelism for consumption, but this will also result in more files across
# the brokers.
##每个topic的分区个数，若是在topic创建时候没有指定的话会被topic创建时的指定参数覆盖
num.partitions=1
​
# The number of threads per data directory to be used for log recovery at startup and flushing at shutdown.
# This value is recommended to be increased for installations with data dirs located in RAID array.
##我们知道segment文件默认会被保留7天的时间，超时的话就
##会被清理，那么清理这件事情就需要有一些线程来做。这里就是
##用来设置恢复和清理data下数据的线程数量
num.recovery.threads.per.data.dir=1
​
############################# Log Flush Policy #############################
​
# Messages are immediately written to the filesystem but by default we only fsync() to sync
# the OS cache lazily. The following configurations control the flush of data to disk.
# There are a few important trade-offs here:
#    1. Durability: Unflushed data may be lost if you are not using replication.
#    2. Latency: Very large flush intervals may lead to latency spikes when the flush does occur as there will be a lot of data to flush.
#    3. Throughput: The flush is generally the most expensive operation, and a small flush interval may lead to exceessive seeks.
# The settings below allow one to configure the flush policy to flush data after a period of time or
# every N messages (or both). This can be done globally and overridden on a per-topic basis.
​
# The number of messages to accept before forcing a flush of data to disk
#log.flush.interval.messages=10000
​
# The maximum amount of time a message can sit in a log before we force a flush
#log.flush.interval.ms=1000
​
############################# Log Retention Policy #############################
​
# The following configurations control the disposal of log segments. The policy can
# be set to delete segments after a period of time, or after a given size has accumulated.
# A segment will be deleted whenever *either* of these criteria are met. Deletion always happens
# from the end of the log.
​
# The minimum age of a log file to be eligible for deletion due to age
##segment文件保留的最长时间，默认保留7天（168小时），
##超时将被删除，也就是说7天之前的数据将被清理掉。
log.retention.hours=168
​
# A size-based retention policy for logs. Segments are pruned from the log as long as the remaining
# segments don't drop below log.retention.bytes. Functions independently of log.retention.hours.
#log.retention.bytes=1073741824
​
# The maximum size of a log segment file. When this size is reached a new log segment will be created.
###日志文件中每个segment的大小，默认为1G
log.segment.bytes=1073741824
​
# The interval at which log segments are checked to see if they can be deleted according
# to the retention policies
##上面的参数设置了每一个segment文件的大小是1G，那么
##就需要有一个东西去定期检查segment文件有没有达到1G，
##多长时间去检查一次，就需要设置一个周期性检查文件大小
##的时间（单位是毫秒）。
log.retention.check.interval.ms=300000
​
############################# Zookeeper #############################
​
# Zookeeper connection string (see zookeeper docs for details).
# This is a comma separated host:port pairs, each corresponding to a zk
# server. e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002".
# You can also append an optional chroot string to the urls to specify the
# root directory for all kafka znodes.
#zookeeper.connect=localhost:2181
##消费者集群通过连接Zookeeper来找到broker。
##zookeeper连接服务器地址
zookeeper.connect=master:2181,worker1:2181,worker2:2181
​
# Timeout in ms for connecting to zookeeper
zookeeper.connection.timeout.ms=6000

启动kafka        

  [root@master kafka]# ./bin/kafka-server-start.sh config/server.properties &
[2018-06-25 02:31:21,931] INFO KafkaConfig values: 
       advertised.host.name = null
       advertised.listeners = null
       advertised.port = null
       authorizer.class.name = 
       auto.create.topics.enable = true
       auto.leader.rebalance.enable = true
       background.threads = 10
       broker.id = 0
       broker.id.generation.enable = true
       broker.rack = null
       compression.type = producer
       connections.max.idle.ms = 600000
       controlled.shutdown.enable = true
       controlled.shutdown.max.retries = 3
       controlled.shutdown.retry.backoff.ms = 5000
       controller.socket.timeout.ms = 30000

创建topic

  #创建topic topic名字为gilbert
[root@master kafka]# ./bin/kafka-topics.sh --create --zookeeper master:2181,worker1:2181,worker2:2181 --replication-factor 3 --partitions 3 --topic gilbert
Created topic "gilbert".

查看topic

  
[root@master kafka]# ./bin/kafka-topics.sh --describe --zookeeper master:2181,worker1:2181,worker2:2181 --topic gilbert
Topic:gilbert   PartitionCount:3        ReplicationFactor:3     Configs:
       Topic: gilbert  Partition: 0    Leader: 2       Replicas: 2,0,1 Isr: 2,0,1
       Topic: gilbert  Partition: 1    Leader: 0       Replicas: 0,1,2 Isr: 0,1,2
       Topic: gilbert  Partition: 2    Leader: 1       Replicas: 1,2,0 Isr: 1,2,0
         
[root@master kafka]# ./bin/kafka-topics.sh --list --zookeeper master:2181,worker1:2181,worker2:2181
gilbert
test

创建producer

  
./bin/kafka-console-producer.sh --broker-list master:9092 -topic gilbert

创建consumer，分别在3台服务器上执行创建消费者

  #192.168.1.128服务器 
[root@master kafka]# ./bin/kafka-console-consumer.sh --zookeeper master:2181,worker1:2181,worker2:2181 -topic gilbert --from-beginning
Using the ConsoleConsumer with old consumer is deprecated and will be removed in a future major release. Consider using the new consumer by passing [bootstrap-server] instead of [zookeeper].
 
#192.168.1.129服务器 
[root@worker1 kafka_2.10-0.10.2.0]# ./bin/kafka-console-consumer.sh --zookeeper master:2181,worker1:2181,worker2:2181 -topic gilbert --from-beginning
Using the ConsoleConsumer with old consumer is deprecated and will be removed in a future major release. Consider using the new consumer by passing [bootstrap-server] instead of [zookeeper].
​
#192.168.1.130服务器 
[root@worker2 kafka_2.10-0.10.2.0]#  ./bin/kafka-console-consumer.sh --zookeeper master:2181,worker1:2181,worker2:2181 -topic gilbert --from-beginning
Using the ConsoleConsumer with old consumer is deprecated and will be removed in a future major release. Consider using the new consumer by passing [bootstrap-server] instead of [zookeeper].
​
​

在#192.168.1.128服务器上生产者控制台输入：hello kafka进行测试

在3台服务器上的消费者都正常接收到消息

删除topic

  
[root@master kafka]# ./bin/kafka-topics.sh --delete --zookeeper master:2181,worker1:2181,worker2:2181 --topic test
Topic test is marked for deletion.
Note: This will have no impact if delete.topic.enable is not set to true

springboot集成kafka

1.生产者kafka-producer

a) pom文件

  <dependency>
 <groupId>org.springframework.boot</groupId>
 <artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
 <groupId>org.springframework.kafka</groupId>
 <artifactId>spring-kafka</artifactId>
</dependency>
<dependency>
 <groupId>com.google.code.gson</groupId>
 <artifactId>gson</artifactId>
 <version>2.8.2</version>
</dependency>
<dependency>
 <groupId>org.projectlombok</groupId>
 <artifactId>lombok</artifactId>
 <optional>true</optional>
</dependency>
<dependency>
 <groupId>org.springframework.boot</groupId>
 <artifactId>spring-boot-starter-test</artifactId>
 <scope>test</scope>
</dependency>

b) yml配置文件,本例为kafka3节点集群

  
spring:
kafka:
   bootstrap-servers: http://master:9092,http://worker1:9092,http://worker2:9092
   producer:
     retries: 0
     batch-size: 16384
     buffer-memory: 33554432
     key-serializer: org.apache.kafka.common.serialization.StringSerializer
     value-serializer: org.apache.kafka.common.serialization.StringSerializer

c) message消息实体类

  
@Data
public class Message {
   private Long id;    //id
   private String msg; //消息
   private Date sendTime;  //时间戳
}

d) 生产者

  @Component
@Slf4j
public class KafkaProducer {
​
   @Autowired
   private KafkaTemplate<String, String> kafkaTemplate;
​
   private Gson gson = new GsonBuilder().create();
​
   //发送消息方法
   public void send() {
       Message message = new Message();
       message.setId(System.currentTimeMillis());
       message.setMsg(UUID.randomUUID().toString());
       message.setSendTime(new Date());
       log.info("+++++++++++++++++++++  message = {}", gson.toJson(message));
       //topic-ideal为主题
       kafkaTemplate.send("topic-ideal", gson.toJson(message));
   }
}

e) 测试类,运行kafkaProducer方法即可

  @RunWith(SpringRunner.class)
@SpringBootTest
public class KafkaProducerApplicationTests {
​
    @Autowired
    private KafkaProducer kafkaProducer;
​
    @Test
    public void kafkaProducer(){
        this.kafkaProducer.send();
    }
​
    @Test
    public void contextLoads() {
    }
​
}

2. 消费者kafka-consumer

a) pom文件

  <dependency>
 <groupId>org.springframework.boot</groupId>
 <artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
 <groupId>org.springframework.kafka</groupId>
 <artifactId>spring-kafka</artifactId>
</dependency>
<dependency>
 <groupId>com.google.code.gson</groupId>
 <artifactId>gson</artifactId>
 <version>2.8.2</version>
</dependency>
<dependency>
 <groupId>org.projectlombok</groupId>
 <artifactId>lombok</artifactId>
 <optional>true</optional>
</dependency>

b) yml配置文件

  
server:
port: 9999
spring:
kafka:
   bootstrap-servers: http://master:9092,http://worker1:9092,http://worker2:9092
   consumer:
     group-id: ideal-consumer-group
     auto-offset-reset: earliest
     enable-auto-commit: true
     auto-commit-interval: 20000
     key-deserializer: org.apache.kafka.common.serialization.StringDeserializer
     value-deserializer: org.apache.kafka.common.serialization.StringDeserializer

c) 消费者类

  
@Component
@Slf4j
public class KafkaConsumer {
​
   @KafkaListener(topics = {
"topic-ideal"})
   public void consumer(ConsumerRecord<?, ?> record){
       Optional<?> kafkaMessage = Optional.ofNullable(record.value());
       if (kafkaMessage.isPresent()) {
           Object message = kafkaMessage.get();
           log.info("----------------- record =" + record);
           log.info("------------------ message =" + message);
       }
   }
}

运行消费者kafka-consumer，再运行kafka-producer工程测试类KafkaProducerApplicationTests中kafkaProducer()方法,可以看到消费者后台正常接收消息