Canal实现MYSQL实时数据同步的示例代码

 更新时间:2024年11月07日 10:11:53   作者:水蓝烟雨  
本文详细介绍了Canal部署的全过程,包括Canal-Admin、Canal-Server和Canal-Adapter的安装和配置,涵盖创建目录、修改配置文件、容器部署等步骤,适用于MYSQL8.0+环境,旨在帮助用户实现MYSQL实时数据同步

部署Canal-Admin

1. 拉取Canal-Admin镜像

为了兼容MYSQL8.0+, 我们需要拉取 v1.1.7的镜像

docker pull canal/canal-admin:v1.1.7

2. 创建目录

mkdir -p /data/canal-server/conf/

3. 创建canal_manager数据库

CREATE DATABASE /*!32312 IF NOT EXISTS*/ `canal_manager` /*!40100 DEFAULT CHARACTER SET utf8 COLLATE utf8_bin */;

USE `canal_manager`;

SET NAMES utf8;
SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------
-- Table structure for canal_adapter_config
-- ----------------------------
DROP TABLE IF EXISTS `canal_adapter_config`;
CREATE TABLE `canal_adapter_config` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `category` varchar(45) NOT NULL,
  `name` varchar(45) NOT NULL,
  `status` varchar(45) DEFAULT NULL,
  `content` text NOT NULL,
  `modified_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Table structure for canal_cluster
-- ----------------------------
DROP TABLE IF EXISTS `canal_cluster`;
CREATE TABLE `canal_cluster` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `name` varchar(63) NOT NULL,
  `zk_hosts` varchar(255) NOT NULL,
  `modified_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Table structure for canal_config
-- ----------------------------
DROP TABLE IF EXISTS `canal_config`;
CREATE TABLE `canal_config` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `cluster_id` bigint(20) DEFAULT NULL,
  `server_id` bigint(20) DEFAULT NULL,
  `name` varchar(45) NOT NULL,
  `status` varchar(45) DEFAULT NULL,
  `content` text NOT NULL,
  `content_md5` varchar(128) NOT NULL,
  `modified_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`),
  UNIQUE KEY `sid_UNIQUE` (`server_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Table structure for canal_instance_config
-- ----------------------------
DROP TABLE IF EXISTS `canal_instance_config`;
CREATE TABLE `canal_instance_config` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `cluster_id` bigint(20) DEFAULT NULL,
  `server_id` bigint(20) DEFAULT NULL,
  `name` varchar(45) NOT NULL,
  `status` varchar(45) DEFAULT NULL,
  `content` text NOT NULL,
  `content_md5` varchar(128) DEFAULT NULL,
  `modified_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`),
  UNIQUE KEY `name_UNIQUE` (`name`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Table structure for canal_node_server
-- ----------------------------
DROP TABLE IF EXISTS `canal_node_server`;
CREATE TABLE `canal_node_server` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `cluster_id` bigint(20) DEFAULT NULL,
  `name` varchar(63) NOT NULL,
  `ip` varchar(63) NOT NULL,
  `admin_port` int(11) DEFAULT NULL,
  `tcp_port` int(11) DEFAULT NULL,
  `metric_port` int(11) DEFAULT NULL,
  `status` varchar(45) DEFAULT NULL,
  `modified_time` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Table structure for canal_user
-- ----------------------------
DROP TABLE IF EXISTS `canal_user`;
CREATE TABLE `canal_user` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `username` varchar(31) NOT NULL,
  `password` varchar(128) NOT NULL,
  `name` varchar(31) NOT NULL,
  `roles` varchar(31) NOT NULL,
  `introduction` varchar(255) DEFAULT NULL,
  `avatar` varchar(255) DEFAULT NULL,
  `creation_date` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

SET FOREIGN_KEY_CHECKS = 1;

-- ----------------------------
-- Records of canal_user
-- ----------------------------
BEGIN;
INSERT INTO `canal_user` VALUES (1, 'admin', '6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9', 'Canal Manager', 'admin', NULL, NULL, '2019-07-14 00:05:28');
COMMIT;

SET FOREIGN_KEY_CHECKS = 1;

4. 启动Canal-Admin

如果是服务器部署的话,记得开放对应的端口号 8089:8089

docker run -d --name canal-admin -p 8089:8089 canal/canal-admin:v1.1.7

5. 拷贝配置文件

docker cp canal-admin:/home/admin/canal-admin/conf/application.yml /data/canal-admin/conf/

6. 删除Canal-Admin容器

docker rm -f canal-admin

7. 修改配置文件

(注意修改注释位置的信息) 一共3处修改

server:
  port: 8089
spring:
  jackson:
    date-format: yyyy-MM-dd HH:mm:ss
    time-zone: GMT+8

spring.datasource:
  address: xxx.xxx.xxx.xxx:3306   	#创建数据库canal_manager的地址及端口号
  database: canal_manager			 
  username: root					#数据库账号
  password: xxxxxx					#数据库密码
  driver-class-name: com.mysql.jdbc.Driver
  url: jdbc:mysql://${spring.datasource.address}/${spring.datasource.database}?useUnicode=true&characterEncoding=UTF-8&useSSL=false
  hikari:
    maximum-pool-size: 30
    minimum-idle: 1

canal:
  adminUser: admin
  adminPasswd: admin

8. 部署Canal-Admin

docker run --name canal-admin -p 8089:8089 \
-v /data/canal-admin/conf/application.yml:/home/admin/canal-admin/conf/application.yml \
-v /data/canal-admin/logs/:/home/admin/canal-admin/logs/ \
-d canal/canal-admin:v1.1.7

9. 访问Canal-Admin

访问 xxx.xxx.xxx.xxx:8089, 前面换成自己的服务器、虚拟机地址

部署Canal-Server

0. 前置工作

查看MYSQL是否 开启log_bin日志 和 日志记录格式 是否为Row
一般都是开启的, 可以通过下列命令在 Navicat 或其他数据库工具进行查看

show variables like 'log_bin';
show variables like 'binlog_format';

授权账号权限, 复制下列命令执行即可

CREATE USER canal IDENTIFIED BY 'canal';  
GRANT SELECT, REPLICATION SLAVE, REPLICATION CLIENT ON *.* TO 'canal'@'%';
FLUSH PRIVILEGES;

1. 拉取Canal-Server镜像

docker pull canal/canal-server:v1.1.7

2. 创建目录

mkdir -p /data/canal-server/conf/

3. 启动Canal-Server

如果是服务器部署的话,记得开放对应的端口号 11111:11111

docker run -d --name canal-server -p 11111:11111 canal/canal-server:v1.1.7

4. 拷贝配置文件

docker cp canal-server:/home/admin/canal-server/conf/canal.properties /data/canal-server/conf/
docker cp canal-server:/home/admin/canal-server/conf/example/instance.properties /data/canal-server/conf/

5. 删除Canal-Server

docker rm -f canal-server

6. 修改配置文件

canal.properties 一共1处修改

# tcp bind ip
canal.ip =
# register ip to zookeeper
canal.register.ip =
canal.port = 11111
canal.metrics.pull.port = 11112

# canal admin config
canal.admin.manager = xxx.xxx.xxx.xxx:8089  # 改成自己的数据库地址
canal.admin.port = 11110
canal.admin.user = admin
canal.admin.passwd = 4ACFE3202A5FF5CF467898FC58AAB1D615029441

canal.zkServers =
# flush data to zk
canal.zookeeper.flush.period = 1000
canal.withoutNetty = false
# tcp, kafka, rocketMQ, rabbitMQ, pulsarMQ
canal.serverMode = tcp
# flush meta cursor/parse position to file
canal.file.data.dir = ${canal.conf.dir}
canal.file.flush.period = 1000
## memory store RingBuffer size, should be Math.pow(2,n)
canal.instance.memory.buffer.size = 16384
## memory store RingBuffer used memory unit size , default 1kb
canal.instance.memory.buffer.memunit = 1024 
## meory store gets mode used MEMSIZE or ITEMSIZE
canal.instance.memory.batch.mode = MEMSIZE
canal.instance.memory.rawEntry = true

## detecing config
canal.instance.detecting.enable = false
canal.instance.detecting.sql = select 1
canal.instance.detecting.interval.time = 3
canal.instance.detecting.retry.threshold = 3
canal.instance.detecting.heartbeatHaEnable = false

canal.instance.transaction.size =  1024
# mysql fallback connected to new master should fallback times
canal.instance.fallbackIntervalInSeconds = 60

# network config
canal.instance.network.receiveBufferSize = 16384
canal.instance.network.sendBufferSize = 16384
canal.instance.network.soTimeout = 30

# binlog filter config
canal.instance.filter.druid.ddl = true
canal.instance.filter.query.dcl = false
canal.instance.filter.query.dml = false
canal.instance.filter.query.ddl = false
canal.instance.filter.table.error = false
canal.instance.filter.rows = false
canal.instance.filter.transaction.entry = false
canal.instance.filter.dml.insert = false
canal.instance.filter.dml.update = false
canal.instance.filter.dml.delete = false

# binlog format/image check
canal.instance.binlog.format = ROW,STATEMENT,MIXED 
canal.instance.binlog.image = FULL,MINIMAL,NOBLOB

# binlog ddl isolation
canal.instance.get.ddl.isolation = false

# parallel parser config
canal.instance.parser.parallel = true
canal.instance.parser.parallelBufferSize = 256

# table meta tsdb info
canal.instance.tsdb.enable = true
canal.instance.tsdb.dir = ${canal.file.data.dir:../conf}/${canal.instance.destination:}
canal.instance.tsdb.url = jdbc:h2:${canal.instance.tsdb.dir}/h2;CACHE_SIZE=1000;MODE=MYSQL;
canal.instance.tsdb.dbUsername = canal
canal.instance.tsdb.dbPassword = canal
# dump snapshot interval, default 24 hour
canal.instance.tsdb.snapshot.interval = 24
# purge snapshot expire , default 360 hour(15 days)
canal.instance.tsdb.snapshot.expire = 360

#################################################
######### 		destinations		#############
#################################################
canal.destinations = example
# conf root dir
canal.conf.dir = ../conf
# auto scan instance dir add/remove and start/stop instance
canal.auto.scan = true
canal.auto.scan.interval = 5
canal.auto.reset.latest.pos.mode = false

canal.instance.tsdb.spring.xml = classpath:spring/tsdb/h2-tsdb.xml

canal.instance.global.mode = spring
canal.instance.global.lazy = false
canal.instance.global.manager.address = ${canal.admin.manager}
canal.instance.global.spring.xml = classpath:spring/file-instance.xml

# canal admin config
canal.admin.manager = xxx.xxx.xxx.xxx:8089 # 改成自己的数据库地址
# admin auto register
canal.admin.register.auto = true
canal.admin.register.cluster =
canal.admin.register.name =

instance.properties 一共2处修改

#################################################
## mysql serverId , v1.0.26+ will autoGen
 canal.instance.mysql.slaveId=10 # 这里的ID不要和Mysql的重复即可,可以直接填10

# enable gtid use true/false
canal.instance.gtidon=false

# position info
canal.instance.master.address=xxx.xxx.xxx.xxx:3306 # 改成需要监听的数据库地址
canal.instance.master.journal.name=
canal.instance.master.position=
canal.instance.master.timestamp=
canal.instance.master.gtid=

# rds oss binlog
canal.instance.rds.accesskey=
canal.instance.rds.secretkey=
canal.instance.rds.instanceId=

# table meta tsdb info
canal.instance.tsdb.enable=true

# username/password
canal.instance.dbUsername=canal
canal.instance.dbPassword=canal
canal.instance.connectionCharset = UTF-8
canal.instance.enableDruid=false

# table regex
canal.instance.filter.regex=.*\\..*
# table black regex
canal.instance.filter.black.regex=mysql\\.slave_.*

# mq config
canal.mq.topic=example
canal.mq.partition=0
canal.instance.multi.stream.on=false
#################################################

7. 部署Canal-Server

docker run --name canal-server -p 11111:11111 \
-v /data/canal-server/conf/instance.properties:/home/admin/canal-server/conf/example/instance.properties \
-v /data/canal-server/conf/canal.properties:/home/admin/canal-server/conf/canal.properties \
-v /data/canal-server/logs/:/home/docker/canal-server/logs/ \
-d canal/canal-server:v1.1.7

部署Canal-Adapter

由于这个 Canal-Adapter 作者并没有上传对应的镜像
但是他上传了对应的 tar ,所以我们可以制作对应的镜像
Canal-Adapter 的下载链接: Canal-Adapter

在这里插入图片描述

1. 创建对应的文件,文件如下

路径尽量跟我的一致 /opt/canal/ ,因为后面的文件都是在这个路径下

在这里插入图片描述

2. 对应的文件内容如下

Dockerfile

FROM openjdk:11
COPY canal.adapter-*.tar.gz /tmp/
	
RUN \
    mkdir -p /opt/canal-adapter && \
    tar -zxf /tmp/canal.adapter-*.tar.gz -C /opt/canal-adapter && \
    rm -r /tmp/canal.adapter-*.tar.gz

COPY startup.sh /opt/canal-adapter/bin/startup.sh

WORKDIR /opt/canal-adapter

CMD ["sh", "-c", "sh /opt/canal-adapter/bin/startup.sh && tail -F logs/adapter/adapter.log"]

startup.sh

#!/bin/bash

current_path=`pwd`
case "`uname`" in
    Linux)
		bin_abs_path=$(readlink -f $(dirname $0))
		;;
	*)
		bin_abs_path=`cd $(dirname $0); pwd`
		;;
esac
base=${bin_abs_path}/..
export LANG=en_US.UTF-8
export BASE=$base

if [ -f $base/bin/adapter.pid ] ; then
	echo "found adapter.pid , Please run stop.sh first ,then startup.sh" 2>&2
    exit 1
fi

if [ ! -d $base/logs ] ; then
	mkdir -p $base/logs
fi

## set java path
if [ -z "$JAVA" ] ; then
  JAVA=$(which java)
fi

ALIBABA_JAVA="/usr/alibaba/java/bin/java"
TAOBAO_JAVA="/opt/taobao/java/bin/java"
if [ -z "$JAVA" ]; then
  if [ -f $ALIBABA_JAVA ] ; then
  	JAVA=$ALIBABA_JAVA
  elif [ -f $TAOBAO_JAVA ] ; then
  	JAVA=$TAOBAO_JAVA
  else
  	echo "Cannot find a Java JDK. Please set either set JAVA or put java (>=1.5) in your PATH." 2>&2
    exit 1
  fi
fi

case "$#"
in
0 )
  ;;
2 )
  if [ "$1" = "debug" ]; then
    DEBUG_PORT=$2
    DEBUG_SUSPEND="n"
    JAVA_DEBUG_OPT="-Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,address=$DEBUG_PORT,server=y,suspend=$DEBUG_SUSPEND"
  fi
  ;;
* )
  echo "THE PARAMETERS MUST BE TWO OR LESS.PLEASE CHECK AGAIN."
  exit;;
esac

str=`file -L $JAVA | grep 64-bit`
if [ -n "$str" ]; then
	JAVA_OPTS="-server -Xms2048m -Xmx3072m -Xmn1024m -XX:SurvivorRatio=2 -Xss256k -XX:+DisableExplicitGC -XX:+HeapDumpOnOutOfMemoryError"
else
	JAVA_OPTS="-server -Xms1024m -Xmx1024m -XX:NewSize=256m -XX:MaxNewSize=256m -XX:MaxPermSize=128m "
fi

JAVA_OPTS=" $JAVA_OPTS -Djava.awt.headless=true -Djava.net.preferIPv4Stack=true -Dfile.encoding=UTF-8"
ADAPTER_OPTS="-DappName=canal-adapter"

for i in $base/lib/*;
    do CLASSPATH=$i:"$CLASSPATH";
done

CLASSPATH="$base/conf:$CLASSPATH";

echo "cd to $bin_abs_path for workaround relative path"
cd $bin_abs_path

echo CLASSPATH :$CLASSPATH
exec $JAVA $JAVA_OPTS $JAVA_DEBUG_OPT $ADAPTER_OPTS -classpath .:$CLASSPATH com.alibaba.otter.canal.adapter.launcher.CanalAdapterApplication

3. 构造 Canal-Adapter 镜像

cd /opt/canal
docker build -t canal/canal-adapter:v1.1.7 .

4. 创建目录

mkdir -p /data/canal-adapter/conf/es7

5. 启动Canal-Adapter

docker run -d --name canal-adapter -p 8081:8081 canal/canal-adapter:v1.1.7

6. 拷贝配置文件

docker cp canal-adapter:/opt/canal-adapter/conf/application.yml /data/canal-adapter/conf/
docker cp canal-adapter:/opt/canal-adapter/conf/bootstrap.yml /data/canal-adapter/conf/
docker cp canal-adapter:/opt/canal-adapter/conf/es7/mytest_user.yml /data/canal-adapter/conf/es7

7. 删除Canal-Adapter

docker rm -f canal-adapter

8. 修改配置文件

application.yml 一共7处地方

server:
  port: 8081
spring:
  jackson:
    date-format: yyyy-MM-dd HH:mm:ss
    time-zone: GMT+8
    default-property-inclusion: non_null

canal.conf:
  mode: tcp #tcp kafka rocketMQ rabbitMQ
  flatMessage: true
  zookeeperHosts:
  syncBatchSize: 1000
  retries: -1
  timeout:
  accessKey:
  secretKey:
  consumerProperties:
    # canal tcp consumer
    canal.tcp.server.host: xxx.xxx.xxx.xxx:11111 #改成部署canal-server的地址
    canal.tcp.zookeeper.hosts:
    canal.tcp.batch.size: 500
    canal.tcp.username:
    canal.tcp.password:

  srcDataSources:
    defaultDS:
      url: jdbc:mysql://xxx.xxx.xxx:3341/infusion-xxxxx?useUnicode=true # 监听的数据库地址
      username: root                           #数据库账号
      password: xxxxxxx						   #数据库密码
  canalAdapters:
  - instance: example 						   #如果没改过的话 默认这个即可
    groups:
    - groupId: g1
      outerAdapters:
      - name: logger
      - name: es7
        hosts: http://xxx.xxx.xxx:9200  	   #部署Es的服务器地址
        properties:
          mode: rest # or rest
          # security.auth: test:123456 #  only used for rest mode
          cluster.name: es					    #部署Es的容器名字

bootstrap.yml

canal:
  manager:
    jdbc:
      url: jdbc:mysql://xxxxxx:3306/canal_manager?useUnicode=true&characterEncoding=UTF-8
      username: root
      password: xxxxxxx

coupon_record.yml 一共3处地方

dataSourceKey: defaultDS 
destination: example        #如果之前canal-server没改就使用默认example
groupId: g1 
esMapping:
  _index: coupon_record			#对应索引库名称
  _id: _id 
  sql: "select id as _id,coupon_id,create_time,use_state,openid,user_type,user_name,coupon_title,start_time,end_time,order_id,price,condition_price,del_flag from sys_coupon_record"   
  commitBatch: 3000

9. 部署Canal-Adapter

docker run --name canal-adapter -p 8081:8081 \
-v /data/canal-adapter/conf/application.yml:/opt/canal-adapter/conf/application.yml \
-v /data/canal-adapter/conf/bootstrap.yml:/opt/canal-adapter/conf/bootstrap.yml \
-v /data/canal-adapter/conf/es7:/opt/canal-adapter/conf/es7 \
-v /data/canal-adapter/logs:/opt/canal-adapter/logs \
-d canal/canal-adapter:v1.1.7

部署Canal三件套到此结束啦,内容可能有点多,需要认真理解!

到此这篇关于Canal实现MYSQL实时数据同步的示例代码的文章就介绍到这了,更多相关Canal MYSQL实时数据同步内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家!

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