https://blog.csdn.net/Carson073/article/details/125175748

背景:以用户日志为例,写一个从Kafka实时同步到MySQL的实战Demo

1、SQL建表语句

    DROP TABLE IF EXISTS `user_log`;
    CREATE TABLE `user_log` (
      `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
      `user_id` int(11) DEFAULT NULL,
      `url` varchar(255) DEFAULT NULL,
      `create_time` timestamp NULL DEFAULT NULL,
      PRIMARY KEY (`id`)
    ) ENGINE=InnoDB AUTO_INCREMENT=2178 DEFAULT CHARSET=utf8;

    SET FOREIGN_KEY_CHECKS = 1;

2、Maven

<?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>org.example</groupId>
    <artifactId>flink-source-kafka-mysql-demo</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <flink.version>1.13.6</flink.version>
        <scala.binary.version>2.11</scala.binary.version>
    </properties>


    <dependencies>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.34</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.28</version>
            <scope>compile</scope>
        </dependency>
        <!--工具包依赖-->
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>23.0</version>
        </dependency>
        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
            <version>2.8.5</version>
        </dependency>
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.5.2</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.4</version>
        </dependency>
        <dependency>
            <groupId>com.jayway.jsonpath</groupId>
            <artifactId>json-path</artifactId>
            <version>2.4.0</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>joda-time</groupId>
            <artifactId>joda-time</artifactId>
            <version>2.9.9</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
        <!--state backend-->
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-statebackend-rocksdb_${scala.binary.version}</artifactId>
            <version>${flink.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-connector-kafka_${scala.binary.version}</artifactId>
            <version>${flink.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-java</artifactId>
            <version>${flink.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-streaming-java_${scala.binary.version}</artifactId>
            <version>${flink.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-clients_${scala.binary.version}</artifactId>
            <version>${flink.version}</version>
        </dependency>

        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-runtime-web_${scala.binary.version}</artifactId>
            <version>${flink.version}</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba.ververica</groupId>
            <artifactId>flink-connector-mysql-cdc</artifactId>
            <version>1.4.0</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>8</source>
                    <target>8</target>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>3.1.0</version>
                <configuration>
                    <createDependencyReducedPom>false</createDependencyReducedPom>
                </configuration>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>

                        <configuration>
                            <transformers>

                                <transformer
                                        implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                                    <!--如果要打包的话,这里要换成对应的 main class-->
                                    <mainClass>com.zhisheng.data.sources.userlog.UserLogKafka2MySQLMain</mainClass>
                                </transformer>
                                <transformer
                                        implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                                    <resource>reference.conf</resource>
                                </transformer>
                            </transformers>
                            <filters>
                                <filter>
                                    <artifact>*:*:*:*</artifact>
                                    <excludes>
                                        <exclude>META-INF/*.SF</exclude>
                                        <exclude>META-INF/*.DSA</exclude>
                                        <exclude>META-INF/*.RSA</exclude>
                                    </excludes>
                                </filter>
                            </filters>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

</project>

3、Java类

实体类

package com.zhisheng.data.sources.userlog;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.sql.Timestamp;

/**

Kafka模拟生产者类

 package com.zhisheng.data.sources.userlog;

import com.alibaba.fastjson.JSON;
import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerRecord;

import java.sql.Timestamp;
import java.util.Properties;

/**
 * 往kafka中写数据,模拟生产者
 */
public class KafkaUtilsProducer {
    public static final String broker_list = "10.252.92.4:9092";
    public static final String topic = "user_log";  //kafka topic 需要和 flink 程序用同一个 topic

    public static void writeToKafka() throws InterruptedException {
        Properties props = new Properties();
        props.put("bootstrap.servers", broker_list);
        props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
        KafkaProducer producer = new KafkaProducer<String, String>(props);
        int i = 0;
        while (true) {
            Thread.sleep(100L);// 每隔100ms 发送一次
            UserLog userLog = new UserLog(i, "https://www.baidu.com/" + i, new Timestamp(System.currentTimeMillis()));
            ProducerRecord record = new ProducerRecord<String, String>(topic, null, null, JSON.toJSONString(userLog));
            producer.send(record);
            System.out.println("发送用户日志: " + JSON.toJSONString(userLog));
            if (i % 10 == 0) {
                producer.flush();
            }
            i++;
        }
    }

    public static void main(String[] args) throws InterruptedException {
        writeToKafka();
    }
}

写入MySQL的Sink类

package com.zhisheng.data.sources.userlog;

import com.mysql.jdbc.JDBC4PreparedStatement;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.functions.sink.RichSinkFunction;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;

/**
 * 算子
 */
public class UserLogSinkToMySQL extends RichSinkFunction<UserLog> {
    PreparedStatement ps;
    private Connection connection;

    /**
     * open() 方法中建立连接,这样不用每次 invoke 的时候都要建立连接和释放连接
     *
     * @param parameters
     * @throws Exception
     */
    @Override
    public void open(Configuration parameters) throws Exception {
        super.open(parameters);
        connection = getConnection();
        String sql = "insert into user_log(user_id, url, create_time) values(?, ?, ?);";
        ps = this.connection.prepareStatement(sql);
    }

    @Override
    public void close() throws Exception {
        super.close();
        //关闭连接和释放资源
        if (connection != null) {
            connection.close();
        }
        if (ps != null) {
            ps.close();
        }
    }

    /**
     * 每条数据的插入都要调用一次 invoke() 方法
     *
     * @param value
     * @param context
     * @throws Exception
     */
    @Override
    public void invoke(UserLog value, Context context) throws Exception {
        //组装数据,执行插入操作
        ps.setInt(1, value.getUserId());
        ps.setString(2, value.getUrl());
        ps.setTimestamp(3, value.getCreateTime());
        String sqlLog = ((JDBC4PreparedStatement) ps).asSql();
        System.out.println("sqlLog:" + sqlLog);
        ps.executeUpdate();
    }

    private static Connection getConnection() {
        Connection con = null;
        try {
            Class.forName("com.mysql.jdbc.Driver");
            con = DriverManager.getConnection("jdbc:mysql://10.252.92.4:30006/test_flink?useUnicode=true&characterEncoding=UTF-8",
                    "root", "root");
        } catch (Exception e) {
            System.out.println("-----------mysql get connection has exception , msg = " + e.getMessage());
        }
        return con;
    }
}

Kafka同步到MySQL的主类

package com.zhisheng.data.sources.userlog;

import com.alibaba.fastjson.JSON;
import org.apache.flink.api.common.serialization.SimpleStringSchema;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer011;

import java.util.Properties;

public class UserLogKafka2MySQLMain {
    public static void main(String[] args) throws Exception {
        final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

        Properties props = new Properties();
        props.put("bootstrap.servers", "10.252.92.4:9092");
        props.put("zookeeper.connect", "10.252.92.4:2181");
        props.put("group.id", "metric-group");
        props.put("key.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.put("value.deserializer", "org.apache.kafka.common.serialization.StringDeserializer");
        props.put("auto.offset.reset", "latest");

        SingleOutputStreamOperator<UserLog> userLog = env.addSource(new FlinkKafkaConsumer011<>(
                "user_log",   //这个 kafka topic 需要和上面的工具类的 topic 一致
                new SimpleStringSchema(),
                props)).setParallelism(1)
                .map(string -> JSON.parseObject(string, UserLog.class)); //Fastjson 解析字符串成 student 对象

        userLog.addSink(new UserLogSinkToMySQL()); //数据 sink 到 mysql

        env.execute("Flink Job UserLog Kafka to MySQL");
    }
}

4、本地执行

记得这个要勾上不然会报错

执行成功

查看数据库

5、打包发布


作者:Jeebiz  创建时间:2022-10-16 01:06
 更新时间:2024-07-10 22:56