三、springboot+canal+rocketmq+redis集成

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前言

前面将canal与redis直接集成进了springboot，我们需要在代码中建立canal的连接。
考虑到canal中对mq的支持，我们再实现一个通过mq去实现redis与mq消息的同步。

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提示：以下是本篇文章正文内容，下面案例可供参考

一、修改canal服务的配置

修改cana.properties文件，加入rocketmq的配置

修改example实例下的instance.properties文件，指定rocketmq的topic

重启canal服务

二、springboot中集成rocketmq

1.引入依赖

代码如下（示例）：

<dependency>
            <groupId>org.apache.rocketmqgroupId>
            <artifactId>rocketmq-spring-boot-starterartifactId>
            <version>2.1.1version>
dependency>

添加rocketmq配置

在application.properties中加入rocketmq相关配置

# 请填写自己的rocketmq相关ip端口
rocketmq.name-server=rocketmq.lee.com:9876
# 这里指定的生产组需要与canal.properties中rocketmq.producer.group配置一致
rocketmq.producer.group=test
rocketmq.producer.max-message-size=131072
rocketmq.producer.send-message-timeout=3000

添加消费者监听类

代码如下（示例）：

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
import com.lee.canal.entity.CanalDtoEntity;
import com.lee.canal.entity.UserEntity;
import com.lee.utils.RedisUtils;
import lombok.extern.slf4j.Slf4j;
import org.apache.rocketmq.common.message.MessageExt;
import org.apache.rocketmq.spring.annotation.RocketMQMessageListener;
import org.apache.rocketmq.spring.core.RocketMQListener;
import org.springframework.stereotype.Component;

import java.util.List;

/**
 * 创建消费者监听
 * @RocketMQMessageListener中topic为canal中配置的topic
 * @author 联想
 */
@Slf4j
@Component
@RocketMQMessageListener(topic = "example",consumerGroup = "example",selectorExpression="*")
public class UserServiceRocketMqImpl implements RocketMQListener<MessageExt> {

    /**
     * 将消息同步到redis中
     * 消息基本结构
     * {
     *     "data":[
     *         {
     *             "id":"10",
     *             "username":"bffafaaa",
     *             "telephone":"12345"
     *         }
     *     ],
     *     "database":"canal_test",
     *     "es":1649838746000,
     *     "id":10,
     *     "isDdl":false,
     *     "mysqlType":{
     *         "id":"int(11)",
     *         "username":"varchar(60)",
     *         "telephone":"varchar(30)"
     *     },
     *     "old":[
     *         {
     *             "username":"bffafaa"
     *         }
     *     ],
     *     "pkNames":[
     *         "id"
     *     ],
     *     "sql":"",
     *     "sqlType":{
     *         "id":4,
     *         "username":12,
     *         "telephone":12
     *     },
     *     "table":"t_user",
     *     "ts":1649838747174,
     *     "type":"UPDATE"
     * }
     * @param msg
     */
    @Override
    public void onMessage(MessageExt msg) {
        String message = new String(msg.getBody());
        log.info("收到消息{}", message);

        // 将消息转换为 java对象
        CanalDtoEntity entity = JSONObject.parseObject(message, CanalDtoEntity.class);
        // 判断是否是ddl语句
        if(!entity.isDdl()){
            // 获取表名
            String tableName = entity.getTable();
            // 获取数据
            List<UserEntity> datas = entity.getData();

            // 根据type类型判断为增删改操作
            if("INSERT".equals(entity.getType()) || "UPDATE".equals(entity.getType())){
                for (UserEntity u: datas ) {
                    RedisUtils.stringSet(tableName+":"+u.getId(),JSON.toJSONString(u));
                }
            }else if("DELETE".equals(entity.getType())){
                for (UserEntity u: datas ) {
                    RedisUtils.delKey(tableName+":"+u.getId());
                }
            }
        }



    }
}

对应的entity代码

import lombok.Data;
import lombok.ToString;

import java.util.List;

/**
 * canal传输的user整体结构
 * @author 联想
 */
@Data
@ToString
public class CanalDtoEntity {

    private List<UserEntity> data;

    private String database;

    private long es;
    private int id;
    //是否是DDL语句
    private boolean isDdl;

    //表结构的字段类型
    private MysqlTypeEntity mysqlType;
    //UPDATE语句，旧数据
    private String old;
    //主键名称
    private List<String> pkNames;
    //sql语句
    private String sql;

    private SqlTypeEntity sqlType;
    //表名
    private String table;

    private long ts;
    //(新增)INSERT、(更新)UPDATE、(删除)DELETE、(删除表)ERASE等等
    private String type;
}

import lombok.Data;
import lombok.ToString;

@Data
@ToString
public class MysqlTypeEntity {
    private String id;
    private String username;
    private String telephone;
}

@Data
@ToString
public class SqlTypeEntity {
    private Integer id;
    private Integer username;
    private Integer telephone;
}

import lombok.Data;
import lombok.ToString;

import java.io.Serializable;

/**
 * @author 联想
 */
@Data
@ToString
public class UserEntity implements Serializable {

    private Long id;
    private String username;
    private String telephone;
}

启动springboot

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验证截图

依次执行sql

insert into t_user(username,telephone) VALUES ("张三","12345678910");
update t_user set username = "胡八一";
DELETE from t_user where username = "胡八一";

控制台日志

rocket控制台截图

redis截图