前言
在搭建时候,发现几个易错点(坑点),并一一填过
1. mysql 版本尽量5.7以下(官方有支持的版本)
2. canal运行方式
一、准备
平台:Ubuntu 16.04
MySQL: 5.7.22
MySQL 安装(指定版本)
# 指定版本:apt-get install mysql-client-core-* (* 为 版本号)
apt-get install mysql-client-core-5.7
apt-get install mysql-client-5.7
apt-get install mysql-server-5.7
MySQL 相关命令
# 服务开启
service mysql start
# 服务关闭
service mysql stop
# 登录
mysql -uxxx -pyyy (xxx 为账号, yyy为密码)
MySQL 对应目录
- 数据库目录:
/var/lib/mysql
- 配置文件:
/usr/share/mysql
,/etc/mysql
- 相关命令:
/usr/bin
,/usr/sbin
- 启动脚本:
etc/init.d/mysql
二、配置MySQL
(1)在/etc/mysql/my.cnf
中添加
[mysqld]
log-bin=mysql-bin #添加这一行就ok
binlog-format=ROW #选择row模式
server_id=1 #配置mysql replaction需要定义,不能和canal的slaveId重复
(2)在mysql中配置canal数据库管理用户,配置相应权限
CREATE USER canal IDENTIFIED BY 'canal';
GRANT SELECT, REPLICATION SLAVE, REPLICATION CLIENT ON *.* TO 'canal'@'%';
-- GRANT ALL PRIVILEGES ON *.* TO 'canal'@'%' ;
FLUSH PRIVILEGES;
三、搭建Canal
(1)下载
wget https://github.com/alibaba/canal/releases/download/canal-1.0.17/canal.deployer-1.0.24.tar.gz
(2)解压
在 /tmp
目录下的文件在重启后会被自动删除
mkdir /tmp/canal
tar zxvf canal.deployer-$version.tar.gz -C /tmp/canal
(3)修改配置
sudo vi /tmp/canal/conf/example/instance.properties
(4)启动
./bin/startup.sh
(5)查看日志
vi /tmp/canal/logs/canal/canal.log
vi /tmp/canal/logs/example/example.log
(6)关闭
./bin/stop.sh
四、搭建canal-client
Maven 配置
<dependency>
<groupId>com.alibaba.otter</groupId>
<artifactId>canal.client</artifactId>
<version>1.0.12</version>
</dependency>
CanalDemo.java
package com.donaldy.platform.canalyoung.demo;
import java.net.InetSocketAddress;
import java.util.List;
import com.alibaba.otter.canal.client.CanalConnectors;
import com.alibaba.otter.canal.common.utils.AddressUtils;
import com.alibaba.otter.canal.client.CanalConnector;
import com.alibaba.otter.canal.protocol.Message;
import com.alibaba.otter.canal.protocol.CanalEntry.Column;
import com.alibaba.otter.canal.protocol.CanalEntry.Entry;
import com.alibaba.otter.canal.protocol.CanalEntry.EntryType;
import com.alibaba.otter.canal.protocol.CanalEntry.EventType;
import com.alibaba.otter.canal.protocol.CanalEntry.RowChange;
import com.alibaba.otter.canal.protocol.CanalEntry.RowData;
public class CanalDemo {
public static void main(String args[]) {
// 创建链接
CanalConnector connector = CanalConnectors.newSingleConnector(new InetSocketAddress(AddressUtils.getHostIp(),
11111), "example", "", "");
int batchSize = 1000;
int emptyCount = 0;
try {
connector.connect();
connector.subscribe(".*\\..*");
connector.rollback();
int totalEmptyCount = 120;
while (emptyCount < totalEmptyCount) {
Message message = connector.getWithoutAck(batchSize); // 获取指定数量的数据
long batchId = message.getId();
int size = message.getEntries().size();
if (batchId == -1 || size == 0) {
emptyCount++;
System.out.println("empty count : " + emptyCount);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
}
} else {
emptyCount = 0;
// System.out.printf("message[batchId=%s,size=%s] \n", batchId, size);
printEntry(message.getEntries());
}
connector.ack(batchId); // 提交确认
// connector.rollback(batchId); // 处理失败, 回滚数据
}
System.out.println("empty too many times, exit");
} finally {
connector.disconnect();
}
}
private static void printEntry(List<Entry> entrys) {
for (Entry entry : entrys) {
if (entry.getEntryType() == EntryType.TRANSACTIONBEGIN || entry.getEntryType() == EntryType.TRANSACTIONEND) {
continue;
}
RowChange rowChage = null;
try {
rowChage = RowChange.parseFrom(entry.getStoreValue());
} catch (Exception e) {
throw new RuntimeException("ERROR ## parser of eromanga-event has an error , data:" + entry.toString(),
e);
}
EventType eventType = rowChage.getEventType();
System.out.println(String.format("================> binlog[%s:%s] , name[%s,%s] , eventType : %s",
entry.getHeader().getLogfileName(), entry.getHeader().getLogfileOffset(),
entry.getHeader().getSchemaName(), entry.getHeader().getTableName(),
eventType));
for (RowData rowData : rowChage.getRowDatasList()) {
if (eventType == EventType.DELETE) {
printColumn(rowData.getBeforeColumnsList());
} else if (eventType == EventType.INSERT) {
printColumn(rowData.getAfterColumnsList());
} else {
System.out.println("-------> before");
printColumn(rowData.getBeforeColumnsList());
System.out.println("-------> after");
printColumn(rowData.getAfterColumnsList());
}
}
}
}
private static void printColumn(List<Column> columns) {
for (Column column : columns) {
System.out.println(column.getName() + " : " + column.getValue() + " update=" + column.getUpdated());
}
}
}
运行
首先启动Canal Server,即之前的 ./bin/startup.sh
创建数据库,表,插入记录
# 创建数据库
create database test;
use test;
# 创建表
create table test (
uid int (4) primary key not null auto_increment,
name varchar(10) not null);
# 插入记录
insert into test (name) values('10');
五、参考资料
https://github.com/alibaba/canal/wiki/QuickStart
https://github.com/alibaba/canal/wiki/ClientExample
https://blog.csdn.net/hackerwin7/article/details/37923607
https://blog.csdn.net/zjerryj/article/details/77152226