基于docker-compose部署canal

canal由来及相关介绍

需要了解canal框架介绍，安装及源码请参考wiki；基本安装过程及demo，官方git上都介绍的很清楚，强烈建议阅读git上相关介绍。

canal部署前Mysql相关设定

• 对于自建 MySQL , 需要先开启 Binlog 写入功能，配置 binlog-format 为 ROW 模式，my.cnf 中配置如下

    [mysqld]
    log-bin=mysql-bin # 开启 binlog
    binlog-format=ROW # 选择 ROW 模式
    server_id=1 # 配置 MySQL replaction 需要定义，不要和 canal 的 slaveId 重复

• ： 创建canal账号
  容器启动mysql,需要进入容器内部设置（docker exec -it mysql bash）
  自建是直接执行命令

mysql -uroot -proot
#创建账号(账号：canal;密码：canal）
CREATE USER canal IDENTIFIED BY 'canal'; 
#授予权限
GRANT SELECT, REPLICATION SLAVE, REPLICATION CLIENT ON *.* TO 'canal'@'%';
#刷新并应用权限
FLUSH PRIVILEGES;

docker-compose部署canal

基于已有docker,docker-compose环境；
docker-compose.yml文件如下：

version: '2'
 
services: 
  canal-server: 
    image: canal/canal-server:v1.1.3
    container_name: canal-server
    ports: 
      - 11111:11111
    environment: 
      - canal.instance.mysql.slaveId=12
      - canal.auto.scan=false
      - canal.destinations=test
      - canal.instance.master.address=192.168.1.9:3306
      - canal.instance.dbUsername=canal
      - canal.instance.dbPassword=canal
      - canal.mq.topic=test
      - canal.instance.filter.regex=esen_approval.apt_approval
    volumes: 
      - ./canal-server/conf/:/admin/canal-server/conf/
      - ./canal-server/logs/:/admin/canal-server/logs/

• canal.instance.mysql.slaveId：slaveId不能与mysql的serverId一样
• canal.instance.master.address：mysql地址
• canal.instance.dbUsername：mysql账号
• canal.instance.dbPassword：mysql密码
• 更多配置项介绍

启动：docker-compose up -d
新建测试项目添加mvn依赖：

<dependency>
    <groupId>com.alibaba.otter</groupId>
    <artifactId>canal.client</artifactId>
    <version>1.1.0</version>
</dependency>

测试类demo:

/**
 * Copyright @ 2019 by com.esenyun, All rights reserved.
 * <p>
 * Project: demo
 * Package: esenyun.canal.demo
 * File: ClientSample.java
 * Date: 2019/9/3 11:49
 */
package esenyun.canal.demo;

import com.alibaba.otter.canal.client.CanalConnector;
import com.alibaba.otter.canal.client.CanalConnectors;
import com.alibaba.otter.canal.protocol.CanalEntry;
import com.alibaba.otter.canal.protocol.Message;

import java.net.InetSocketAddress;
import java.util.List;



public class ClientSample {


    public static void main(String args[]) {
        // 创建链接
        CanalConnector connector = CanalConnectors.newSingleConnector(new InetSocketAddress("192.168.1.29",
                11111), "test", "canal", "canal");
        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<CanalEntry.Entry> entrys) {
        for (CanalEntry.Entry entry : entrys) {
            if (entry.getEntryType() == CanalEntry.EntryType.TRANSACTIONBEGIN || entry.getEntryType() == CanalEntry.EntryType.TRANSACTIONEND) {
                continue;
            }

            CanalEntry.RowChange rowChage = null;
            try {
                rowChage = CanalEntry.RowChange.parseFrom(entry.getStoreValue());
            } catch (Exception e) {
                throw new RuntimeException("ERROR ## parser of eromanga-event has an error , data:" + entry.toString(),
                        e);
            }

            CanalEntry.EventType eventType = rowChage.getEventType();
            System.out.println(String.format("================&gt; binlog[%s:%s] , name[%s,%s] , eventType : %s",
                    entry.getHeader().getLogfileName(), entry.getHeader().getLogfileOffset(),
                    entry.getHeader().getSchemaName(), entry.getHeader().getTableName(),
                    eventType));

            for (CanalEntry.RowData rowData : rowChage.getRowDatasList()) {
                if (eventType == CanalEntry.EventType.DELETE) {
                    printColumn(rowData.getBeforeColumnsList());
                } else if (eventType == CanalEntry.EventType.INSERT) {
                    printColumn(rowData.getAfterColumnsList());
                } else {
                    System.out.println("-------&gt; before");
                    printColumn(rowData.getBeforeColumnsList());
                    System.out.println("-------&gt; after");
                    printColumn(rowData.getAfterColumnsList());
                }
            }
        }
    }

    private static void printColumn(List<CanalEntry.Column> columns) {
        for (CanalEntry.Column column : columns) {
            System.out.println(column.getName() + " : " + column.getValue() + "    update=" + column.getUpdated());
        }
    }
}

启动测试类后，执行插入或更新sql,就可以在控制台看到变动日志了