在docker中使用`canal`同步数据到`elasticsearch`

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准备：

mysql：v5.7
canal-server：v1.4.1
elasticsearch：v7.5.1

创建网络：

docker network create net

创建volume：

docker volume create elasticsearch
docker volume create mysql

创建container：

#mysql
docker run -d --name mysql -p 3306:3306 --privileged=true  -v mysql:/var/lib/mysql -e MYSQL_ROOT_PASSWORD=123 --net net mysql:5.7 --log-bin=mysql-bin --binlog-format=ROW --server_id=101

#canal server
docker run -d --name canal-server --net net  -p 11111:11111 -e canal.instance.master.address=mysql:3306 \
         -e canal.instance.dbUsername=root \
         -e canal.instance.dbPassword=123 \
         -e canal.instance.connectionCharset=UTF-8 canal/canal-server:v1.1.4
         
#elasticsearch
docker run -d --name elasticsearch -p 9200:9200 -v elasticsearch -e "discovery.type=single-node"  --network net elasticsearch:7.5.1

查看mysql配置是否成功：

mysql> show variables like 'log_bin';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| log_bin       | ON    |
+---------------+-------+
2 rows in set (0.00 sec)

mysql> show variables like '%binlog_format';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| binlog_format | ROW   |
+---------------+-------+
1 row in set (0.00 sec)

mysql> show variables like '%server_id';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| server_id     | 101   |
+---------------+-------+
1 row in set (0.00 sec)

mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 |      884 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.01 sec)

授权 canal 链接 MySQL 账号具有作为 MySQL slave的权限

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

客户端代码：

public static void main(String[] args) {
        // 创建链接
        CanalConnector connector = CanalConnectors.newSingleConnector(new InetSocketAddress("ip",
                port), "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() == 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());
        }
    }

创建表以及加入插入数据之后观察控制台的输出：

================&gt; binlog[mysql-bin.000003:1019] , name[canal_data,person] , eventType : CREATE

================&gt; binlog[mysql-bin.000003:1377] , name[canal_data,person] , eventType : INSERT
id : 1    update=true
name : Tony    update=true

使用最新版本的mysql（8.x）可能会导致canal server无法启动

来源：oschina

链接：https://my.oschina.net/u/2486137/blog/3154962

标签

Docker

ElasticSearch

canal