k8s快速部署kafka 3.3.1

在平常开发测试中，使用docker或者k8s快速部署某个组件会是一个不错的选择。kafka 3.3.1作为kraft第一个生产可用版本，本文介绍使用k8s快速部署基于kraft运行的kafka 3.3.1。

构建kafka镜像

首先我们要构建kafka 3.3.1镜像，简单地，我们只需要配置文件、启动脚本以及Dockerfile。

server.properties
start-kafka.sh
Dockerfile

为了在外网环境可以访问k8s中的kafka，需要对server.properties配置文件进行如下修改：

# 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.

#
# This configuration file is intended for use in KRaft mode, where
# Apache ZooKeeper is not present.  See config/kraft/README.md for details.
#

############################# Server Basics #############################

# The role of this server. Setting this puts us in KRaft mode
process.roles=broker,controller

# The node id associated with this instance's roles
node.id=1

# The connect string for the controller quorum
controller.quorum.voters=1@kafka:9093

############################# Socket Server Settings #############################

# The address the socket server listens on.
# Combined nodes (i.e. those with `process.roles=broker,controller`) must list the controller listener here at a minimum.
# If the broker listener is not defined, the default listener will use a host name that is equal to the value of java.net.InetAddress.getCanonicalHostName(),
# with PLAINTEXT listener name, and port 9092.
#   FORMAT:
#     listeners = listener_name://host_name:port
#   EXAMPLE:
#     listeners = PLAINTEXT://your.host.name:9092
listeners = INTERNAL://kafka:9092,EXTERNAL://kafka:30092,CONTROLLER://kafka:9093
# advertised.listeners = INTERNAL://kafka:9092,EXTERNAL://kafka:30092,CONTROLLER://kafka:9093

# Name of listener used for communication between brokers.
inter.broker.listener.name=INTERNAL

# Listener name, hostname and port the broker will advertise to clients.
# If not set, it uses the value for "listeners".
# advertised.listeners=PLAINTEXT://localhost:9092

# A comma-separated list of the names of the listeners used by the controller.
# If no explicit mapping set in `listener.security.protocol.map`, default will be using PLAINTEXT protocol
# This is required if running in KRaft mode.
controller.listener.names=CONTROLLER

# 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=INTERNAL:PLAINTEXT,EXTERNAL:PLAINTEXT,CONTROLLER:PLAINTEXT,PLAINTEXT:PLAINTEXT,SSL:SSL,SASL_PLAINTEXT:SASL_PLAINTEXT,SASL_SSL:SASL_SSL

# The number of threads that the server uses for receiving requests from the network and sending responses to the network
num.network.threads=3

# The number of threads that the server uses for processing requests, which may include disk I/O
num.io.threads=8

# The send buffer (SO_SNDBUF) used by the socket server
socket.send.buffer.bytes=102400

# The receive buffer (SO_RCVBUF) used by the socket server
socket.receive.buffer.bytes=102400

# The maximum size of a request that the socket server will accept (protection against OOM)
socket.request.max.bytes=104857600

############################# Log Basics #############################

# A comma separated list of directories under which to store log files
log.dirs=/data/kafka/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.
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.
num.recovery.threads.per.data.dir=1

############################# Internal Topic Settings  #############################
# The replication factor for the group metadata internal topics "__consumer_offsets" and "__transaction_state"
# For anything other than development testing, a value greater than 1 is recommended to ensure availability such as 3.
offsets.topic.replication.factor=1
transaction.state.log.replication.factor=1
transaction.state.log.min.isr=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 excessive 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
log.retention.hours=168

# A size-based retention policy for logs. Segments are pruned from the log unless the remaining
# segments 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.
log.segment.bytes=1073741824

# The interval at which log segments are checked to see if they can be deleted according
# to the retention policies
log.retention.check.interval.ms=300000

启动脚本start-kafka.sh内容为：

#!/bin/sh

/data/kafka/bin/kafka-storage.sh format \
                    --config /data/kafka/config/kraft/server.properties \
                    --cluster-id $(/data/kafka/bin/kafka-storage.sh random-uuid)

/data/kafka/bin/kafka-server-start.sh /data/kafka/config/kraft/server.properties

Dockerfile内容为：

FROM centos:centos7.9.2009

WORKDIR /data

COPY start-kafka.sh /data
COPY server.properties /data

ARG ZK_VERSION=3.8.0
ARG KAFKA_SCALA_VERSION=2.12
ARG KAFKA_VERSION=3.3.1

EXPOSE 30092

RUN yum update -y
RUN yum install wget java-1.8.0-openjdk-devel java-1.8.0-openjdk -y

RUN wget https://mirrors.tuna.tsinghua.edu.cn/apache/kafka/${KAFKA_VERSION}/kafka_${KAFKA_SCALA_VERSION}-${KAFKA_VERSION}.tgz

RUN tar zxvf kafka_${KAFKA_SCALA_VERSION}-${KAFKA_VERSION}.tgz

RUN ln -s kafka_${KAFKA_SCALA_VERSION}-${KAFKA_VERSION} kafka

RUN rm -rf /data/kafka/config/kraft/server.properties

RUN cp /data/server.properties /data/kafka/config/kraft

RUN mkdir /data/kafka/kafka-logs

RUN chmod a+x /data/start-kafka.sh

CMD ["sh", "/data/start-kafka.sh"]

将上述文件保存到目录下之后执行构建

docker build . --build-arg KAFKA_VERSION=3.3.1 --build-arg ZK_VERSION=3.8.0 --tag xiaozhongcheng2022/kafka:3.3.1 --no-cache=true

即可得到镜像：

K8s部署kafka

基于此镜像我们就可以构建kafka deployment

---
apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: kafka
  name: kafka
spec:
  replicas: 1
  revisionHistoryLimit: 2
  selector:
    matchLabels:
      app: kafka
  template:
    metadata:
      labels:
        app: kafka
    spec:
      hostname: kafka
      containers:
        - env:
            - name: KUBERNETES_NAMESPACE
              valueFrom:
                fieldRef:
                  fieldPath: metadata.namespace
          image: xiaozhongcheng2022/kafka:3.3.1
          imagePullPolicy: IfNotPresent
          name: kafka
          ports:
            - containerPort: 30092
              name: kafka-port
              protocol: TCP
          securityContext:
            privileged: false

将上述配置文件保存为：kafka-deployment.yaml，启动kafka

kubectl apply -f kafka-deployment.yaml

得到：

查看kafka日志：

部署kafka service，将kafka服务通过NodePort暴露出来

---
apiVersion: v1
kind: Service
metadata:
  labels:
    expose: "true"
    app: kafka
  name: kafka
spec:
  type: NodePort
  ports:
    - name: kafka-port
      port: 30092
      protocol: TCP
      nodePort: 30092
  selector:
    app: kafka

将上述文件保存为kafka-service.yaml

kubectl apply -f kafka-service.yaml

Kafka Java Client连接kafka

由于我们在部署kafka deployment时将kafka的hostname设置为kafka，同时也在配置文件里面将hostname设置为kafka，所以我们在使用客户端进行连接是，需要配置本地hosts，将kafka配置为k8s节点IP

package com.zh.ch.bigdata.examples.kafka;

import com.zh.ch.bigdata.examples.utils.PropertiesUtil;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.Producer;
import org.apache.kafka.clients.producer.ProducerRecord;

import java.io.IOException;
import java.util.Properties;

public class KafkaClientExample<K, V> {

    private Producer<K, V> getProducer() throws IOException {
        Properties kafkaConfig = PropertiesUtil.load("kafka/src/main/resources/kafkaConfig.properties");
        return new KafkaProducer<>(kafkaConfig);
    }

    public static void main(String[] args) throws IOException {
        KafkaClientExample<String, String> kafkaClientExample = new KafkaClientExample<>();
        Producer<String, String> producer = kafkaClientExample.getProducer();
        for (int i = 0; i < 100; i++) {
            producer.send(new ProducerRecord<>("my-topic", Integer.toString(i), Integer.toString(i)));
        }
        producer.close();
    }

}

kafkaConfig.properties

bootstrap.servers        =192.168.1.15:30092
linger.ms                =1
key.serializer           =org.apache.kafka.common.serialization.StringSerializer
value.serializer         =org.apache.kafka.common.serialization.StringSerializer

kafka数据持久化

如果需要持久化kafka数据，可使用nfs进行持久化。在已有nfs服务的情况下使用helm部署

helm repo add nfs-subdir-external-provisioner https://kubernetes-sigs.github.io/nfs-subdir-external-provisioner/

helm install nfs-subdir-external-provisioner nfs-subdir-external-provisioner/nfs-subdir-external-provisioner \
    --set nfs.server=192.168.49.1 \
    --set nfs.path=/data1/nfs/rootfs

即可得到名称为nfs-client的StorageClass

使用nfs-client创建pvc

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: kafka-pvc
spec:
  storageClassName: nfs-client
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 50Gi

将上述配置文件保存为kafka-pvc.yaml

kubectl apply -f kafka-pvc.yaml

修改kafka-deployment.yaml

---
apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: kafka
  name: kafka
spec:
  replicas: 1
  revisionHistoryLimit: 2
  selector:
    matchLabels:
      app: kafka
  template:
    metadata:
      labels:
        app: kafka
    spec:
      hostname: kafka
      containers:
        - env:
            - name: KUBERNETES_NAMESPACE
              valueFrom:
                fieldRef:
                  fieldPath: metadata.namespace
          image: xiaozhongcheng2022/kafka:3.3.1
          imagePullPolicy: IfNotPresent
          name: kafka
          ports:
            - containerPort: 30092
              name: kafka-port
              protocol: TCP
          securityContext:
            privileged: false
          volumeMounts:
            - mountPath: /data/kafka/kafka-logs
              name: kafka-pvc
      volumes:
        - name: kafka-pvc
          persistentVolumeClaim:
            claimName: kafka-pvc

查看nfs路径可以看到持久化目录