canal github地址
https://github.com/alibaba/canal/releases
执行这个sql

show MASTER STATUS;

image.png

修改关键配置

canal.instance.master.address=127.0.0.1:3306  #mysql主机和端口
canal.instance.master.journal.name=mysql-bin.000002 #将上图的file填到这里
canal.instance.master.position=2305 #将上图的position填到这里
canal.instance.dbUsername=root #mysql用户名
canal.instance.dbPassword=123456 #mysql密码
canal.instance.enableDruid=false #密码是否加密 如果是true需要填写下面的公钥
# canal.instance.pwdPublicKey=publicKey #密码加密用的公钥

密码加密：命令行切换到druid.jar下 执行该命令，如果密码中有特殊字符需要使用英文双引号包起来

java -cp druid-1.2.13.jar com.alibaba.druid.filter.config.ConfigTools WcBnMiVd"^"MvQTR%1

执行后会生成私钥、公钥、密码

image.png

创建用户并授权，一定要授权！！！！！一定要授权！！！！！一定要授权！！！！！一定要授权！！！！！

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

开启mysql binlog参考这个网址
https://blog.csdn.net/hundan_520520/article/details/123792968?spm=1001.2014.3001.5506
启动canal

windows:bin目录下双击startup.bat
linux:bin目录下执行startup.sh

maven依赖，版本要和你下载的服务端版本一致

  <dependency>
    <groupId>com.alibaba.otter</groupId>
    <artifactId>canal.client</artifactId>
    <version>1.1.4</version>
  </dependency>

上代码

public void canal() {
        // 创建canal连接对象
        CanalConnector connector = CanalConnectors.newSingleConnector(new InetSocketAddress("canal服务主机IP地址", "cannal服务端口", "example", "canal", "canal");
        try {
            //连接
            connector.connect();
            //订阅所有数据库和表 正则表达式 库名.表名
            connector.subscribe("rzt.gov_ref_sys|rzt.gov_user|rzt.gov_info_user|rzt.gov_info");
            connector.rollback();
            while (true) {
                // 获取指定数量的数据
                Message message = connector.getWithoutAck(1000);
                long batchId = message.getId();
                int size = message.getEntries().size();
                if (batchId == -1 || size == 0) {
                    //没有数据，就休眠1秒
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                    }
                } else {
                    //有数据就打印
                    printEntry(message.getEntries());
                }
                // 提交确认
                connector.ack(batchId);
            }
        } 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 parse 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()) {
                //判断增删改操作
                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());
        }
    }