Flink-CDC 动态监控 mysql 数据表

Flink-CDC监控mysql的好处在于，在项目中无需向canal和maxwell那样要先将数据先存入kafka，而是直接将数据拉取到实时流当中。API方式监控import com.alibaba.ververica.cdc.connectors.mysql.MySQLSource;import com.alibaba.ververica.cdc.connectors.mysql.table.S

笑面天下

4498人浏览 · 2022-01-07 12:31:25

笑面天下 · 2022-01-07 12:31:25 发布

Flink-CDC监控mysql的好处在于，在项目中无需向canal和maxwell那样要先将数据先存入kafka，而是直接将数据拉取到实时流当中。

Flink - API方式监控

import com.alibaba.fastjson.JSONObject;
import com.alibaba.ververica.cdc.connectors.mysql.MySQLSource;
import com.alibaba.ververica.cdc.connectors.mysql.table.StartupOptions;
import com.alibaba.ververica.cdc.debezium.DebeziumDeserializationSchema;
import com.alibaba.ververica.cdc.debezium.DebeziumSourceFunction;
import io.debezium.data.Envelope;
import org.apache.flink.api.common.restartstrategy.RestartStrategies;
import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.runtime.state.filesystem.FsStateBackend;
import org.apache.flink.streaming.api.CheckpointingMode;
import org.apache.flink.streaming.api.environment.CheckpointConfig;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.util.Collector;
import org.apache.kafka.connect.data.Field;
import org.apache.kafka.connect.data.Struct;
import org.apache.kafka.connect.source.SourceRecord;

/**
 * @author zyj
 * @Date 2022/1/7 11:49
 * 自定义序列化器
 */
public class FlinkCDC01_CustomSchema {
    public static void main(String[] args) throws Exception {
        // 创建flink环境
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        // 设置并行度
        env.setParallelism(1);

        // 开启检查点，5秒插入一次
        env.enableCheckpointing(5000L, CheckpointingMode.EXACTLY_ONCE);
        // 建立检查点超时时间为1分钟
        env.getCheckpointConfig().setCheckpointTimeout(60000L);
        // 检查点重启次数和重启间隔
        env.setRestartStrategy(RestartStrategies.fixedDelayRestart(2, 2000L));
        // 设置job取消后，检查点是否保留
        env.getCheckpointConfig().enableExternalizedCheckpoints(CheckpointConfig.ExternalizedCheckpointCleanup.RETAIN_ON_CANCELLATION);
        // 设置状态后端
        env.setStateBackend(new FsStateBackend("hdfs:///flinkCDC"));
        // 设置访问HDFS用户名
        System.setProperty("HADOOP_USER_NAME", "zyj");

        DebeziumSourceFunction<String> sourceFunction = MySQLSource.<String>builder()
                .hostname("hadoop110") // mysql主机名
                .port(3306) // mysql 端口号
                .databaseList("project_realtime") // 要监控的数据库名，可写多个
                .tableList("project_realtime.t_user") // 要监控的数据表，数据库.数据表方式
                .username("root") // mysql用户名
                .password("root") // mysql登录密码
                .startupOptions(StartupOptions.initial()) // 从最开始的binlog读取数据
                .deserializer(new MySchema()) // CDC 输出的文件格式
                .build();

        env
                .addSource(sourceFunction)
                .print();

        env.execute();
    }
}

class MySchema implements DebeziumDeserializationSchema<String> {

    @Override
    public void deserialize(SourceRecord sourceRecord, Collector<String> out) throws Exception {
        Struct valueStruct = (Struct) sourceRecord.value();
        Struct sourceStruct = valueStruct.getStruct("source");
        // 获取数据库的名称
        String database = sourceStruct.getString("db");
        // 获取表名
        String table = sourceStruct.getString("table");

        // 获取数据库操作的类型
        String type = Envelope.operationFor(sourceRecord).toString().toLowerCase();
        if (type.equals("create")) {
            type = "insert";
        }

        JSONObject jsonObj = new JSONObject();
        jsonObj.put("database", database);
        jsonObj.put("table", table);
        jsonObj.put("type", type);

        // 获取影响的数据data
        Struct afterStruct = valueStruct.getStruct("after");
        JSONObject dataJsonObj = new JSONObject();
        if (afterStruct != null) {
            for (Field field : afterStruct.schema().fields()) {
                String fieldName = field.name();
                Object fieldValue = afterStruct.get(field);
                dataJsonObj.put(fieldName, fieldValue);
            }
        }
        // 如果是delete操作, data为{}, 空, 防止后续调用产生空指针异常
        jsonObj.put("data", dataJsonObj);

        // 向下游传递数据
        out.collect(jsonObj.toJSONString());
    }

    @Override
    public TypeInformation<String> getProducedType() {
        return TypeInformation.of(String.class);
    }
}

FLink - SQL方式监控

import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.table.api.bridge.java.StreamTableEnvironment;

/**
 * @author zyj
 * @Date 2022/1/8 0:32
 * 通过Flink-CDC动态读取MySQL表中的数据 SQL方式
 */
public class FlinkCDC02_SQL {
    public static void main(String[] args) throws Exception {
        //TODO 1.准备环境
        //1.1 流处理环境
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        // 1.2 表执行环境
        StreamTableEnvironment tableEnv = StreamTableEnvironment.create(env);
        // 1.3 设置并行度
        env.setParallelism(1);

        //TODO 2.创建动态表
        tableEnv.executeSql("CREATE TABLE user_info (" +
                "  id INT," +
                "  name STRING," +
                "  age INT" +
                ") WITH (" +
                "  'connector' = 'mysql-cdc'," +
                "  'hostname' = 'hadoop110'," +
                "  'port' = '3306'," +
                "  'username' = 'root'," +
                "  'password' = 'root'," +
                "  'database-name' = 'project_realtime'," +
                "  'table-name' = 't_user'" +
                ")");

        tableEnv.executeSql("select * from user_info").print();

        env.execute();
    }
}

pom依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.atguigu.gmall</groupId>
    <artifactId>gmall0224-cdc</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-java</artifactId>
            <version>1.12.0</version>
        </dependency>

        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-streaming-java_2.11</artifactId>
            <version>1.12.0</version>
        </dependency>

        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-clients_2.11</artifactId>
            <version>1.12.0</version>
        </dependency>

        <dependency>
            <groupId>org.apache.hadoop</groupId>
            <artifactId>hadoop-client</artifactId>
            <version>3.0.0</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.48</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba.ververica</groupId>
            <artifactId>flink-connector-mysql-cdc</artifactId>
            <version>1.2.0</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.75</version>
        </dependency>

        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-table-planner-blink_2.11</artifactId>
            <version>1.12.0</version>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-assembly-plugin</artifactId>
                <version>3.0.0</version>
                <configuration>
                    <descriptorRefs>
                        <descriptorRef>jar-with-dependencies</descriptorRef>
                    </descriptorRefs>
                </configuration>
                <executions>
                    <execution>
                        <id>make-assembly</id>
                        <phase>package</phase>
                        <goals>
                            <goal>single</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>