FlinkCDC如何实时同步mysql数据到DorisDB/StarRocks

一、创建数据表

1、DorisBD表创建

CREATE TABLE test( 
    id INT, 
    student VARCHAR(32), 
    phone VARCHAR(32) 
) UNIQUE KEY(id) 
DISTRIBUTED BY HASH(id)  
BUCKETS 3 
PROPERTIES("replication_num" = "1");

2、mysql表创建

CREATE TABLE `test` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `student` varchar(30),
  `phone` varchar(30),
  PRIMARY KEY (`id`) USING BTREE
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin;

二、pom依赖

1、查找Latest Version信息，替换下面x.x.x内容

版本信息

2、依赖示例

flink版本：1.13
scala版本：2.11

<dependency>
    <groupId>com.ververicagroupId>
    <artifactId>flink-connector-mysql-cdcartifactId>
    <version>2.2.0version>
dependency>

<dependency>
    <groupId>org.apache.flinkgroupId>
    <artifactId>flink-javaartifactId>
    <version>1.13.6version>
dependency>
<dependency>
    <groupId>org.apache.flinkgroupId>
    <artifactId>flink-clients_2.11artifactId>
    <version>1.13.6version>
dependency>
<dependency>
    <groupId>org.apache.flinkgroupId>
    <artifactId>flink-streaming-java_2.11artifactId>
    <version>1.13.6version>
dependency>
<dependency>
    <groupId>org.apache.flinkgroupId>
    <artifactId>flink-connector-jdbc_2.11artifactId>
    <version>1.13.6version>
dependency>
<dependency>
    <groupId>org.apache.flinkgroupId>
    <artifactId>flink-table-planner-blink_2.11artifactId>
    <version>1.13.6version>
dependency>

<dependency>
    <groupId>com.starrocksgroupId>
    <artifactId>flink-connector-starrocksartifactId>
    <version>1.2.3_flink-1.13_2.11version>
dependency>

代码示例

主类：FlinkToDoris

import com.starrocks.connector.flink.StarRocksSink;
import com.starrocks.connector.flink.table.sink.StarRocksSinkOptions;
import com.ververica.cdc.connectors.mysql.source.MySqlSource;
import com.ververica.cdc.connectors.mysql.table.StartupOptions;
import org.apache.flink.api.common.eventtime.WatermarkStrategy;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;

public class FlinkToDoris {
	public static void main(String[] args) throws Exception {
		StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

		// enable checkpoint
		env.enableCheckpointing(3000);

		MySqlSource<String> mySqlSource = MySqlSource.<String>builder()
		        .hostname("ip")
		        .port(port)
		        .databaseList("db_name") // set captured database
		        .tableList("db_name.table_name") // set captured table
		        .username("xxx")
		        .password("xxx")
		        // 不需要自定义schema可以直接用JsonDebeziumDeserializationSchema
		        //.deserializer(new JsonDebeziumDeserializationSchema())
		        .deserializer(new MyDeserializationSchema)
		        // 从最新数据开始
		        .startupOptions(StartupOptions.latest())
		        // 从最开始的数据开始
		        //.startupOptions(StartupOptions.initial())
		        .build();

		env
	        .fromSource(mySqlSource, WatermarkStrategy.noWatermarks(), "mysql source")
	        .addSink(StarRocksSink.sink(
	                StarRocksSinkOptions.builder()
	                .withProperty("jdbc-url", "jdbc:mysql://fe1_ip:query_port,fe2_ip:query_port,fe3_ip:query_port?xxxxx")
            		.withProperty("load-url", "fe1_ip:http_port;fe2_ip:http_port;fe3_ip:http_port")
	                .withProperty("username", "xxx")
	                .withProperty("password", "xxx")
	                .withProperty("table-name", "xxx")
	                .withProperty("database-name", "xxx")
	                .withProperty("sink.properties.format", "json")
	                .withProperty("sink.properties.strip_outer_array", "true")
	                // 设置并行度，多并行度情况下需要考虑如何保证数据有序性
	                .withProperty("sink.parallelism", "1")
	                .build()));
	                
		env.execute("FlinkToDoris");
	}
}

自定义Schema：MyDeserializationSchema

import com.alibaba.fastjson.JSONObject;
import com.ververica.cdc.debezium.DebeziumDeserializationSchema;
import org.apache.flink.api.common.typeinfo.BasicTypeInfo;
import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.util.Collector;
import org.apache.kafka.connect.source.SourceRecord;
import org.apache.kafka.connect.data.Struct;
import org.apache.kafka.connect.data.Field;
import org.apache.kafka.connect.data.Schema;

import java.util.Date;
import java.util.List;

public class MyDeserializationSchema implements DebeziumDeserializationSchema<String> {

    /**
     * 封装为
     * {"update_time":"2022-9-19 14:24:26","student":"ccc","phone":"ddd","id":16,"is_delete":0}
     * 因为doris是不能根据非主键字段做删除操作的，所以当mysql中有删除操作时，这边边采用逻辑删除的方式，将删出字段标记为已删除
     * 后期在做数据分析时，可以将这部分数据过滤掉即可。
     * is_delete：逻辑删除标志符 0表示正常 1表示删除
     * update_time：数据的更新时间
     */

    @Override
    public void deserialize(SourceRecord sourceRecord, Collector<String> collector) throws Exception {
        JSONObject res = new JSONObject();
        Struct value = (Struct) sourceRecord.value();

        // c: insert; u: update; d: delete
        String op = value.getString("op");

        if ("d".equals(op)) { // 如果是delete操作，则取before中的数据，将其设置为1
            Struct before = value.getStruct("before");
            if (before != null) {
                Schema beforeSchema = before.schema();
                List<Field> beforeFields = beforeSchema.fields();
                for (Field field : beforeFields) {
                    Object beforeValue = before.get(field);
                    res.put(field.name(), beforeValue);
                }
                res.put("is_delete", 1);
                res.put("update_time", new Date().toLocaleString());
            }
        } else { //如果是insert或者update操作，则取after中的数据，将是否删除设置为0
            Struct after = value.getStruct("after");
            if (after != null) {
                Schema afterSchema = after.schema();
                List<Field> afterFields = afterSchema.fields();
                for (Field field : afterFields) {
                    Object afterValue = after.get(field);
                    res.put(field.name(), afterValue);
                }
                res.put("is_delete", 0);
                res.put("update_time", new Date().toLocaleString());
            }
        }
        //输出数据
        collector.collect(res.toString());
    }

    @Override
    public TypeInformation<String> getProducedType() {
        return BasicTypeInfo.STRING_TYPE_INFO;
    }
}

测试

插入数据到mysql

INSERT INTO `test`(student, phone) VALUES('aaa', 'bbb');

DorisDB中查看数据

更新数据到mysql

UPDATE `test` SET student = 'ddd', phone = 'qqq' WHERE id = 20;

DorisDB中查看数据

删除数据到mysql

DELETE FROM `iferry_fall_record_test1` WHERE id = 20;

DorisDB中查看数据