通过 FlinkCDC 实现 MySQL 数据库、表的实时变化监控,这里只把变化打印了出来,后面会实现如何再写入其他 MySQL 库中;
1、开启 MySQL 的 binlog
在 my.cnf 中开启 binlog,我这里指定了 test 库,然后重启 MySQL
server.id=1
log-bin=mysql-bin
binlog-do-db=test
2、在 MySQL 中创建测试库和表
mysql> create database test;
mysql> create table user_info(id int unsigned not null auto_increment primary key, username varchar(60), sex tinyint(1), nickname varchar(60), addr varchar(255))ENGINE=InnoDB default charset=utf8mb4;
3、Flink 代码
在 IDEA 中新建工程 flinkcdc
pom.xml
<?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.zsoft.flinkcdc</groupId>
<artifactId>flinkcdc</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
<flink.version>1.13.1</flink.version>
</properties>
<dependencies>
<!-- FlinkCDC DataStream 方式 -->
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-java</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-streaming-java_2.12</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-clients_2.12</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-client</artifactId>
<version>3.1.3</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.22</version>
</dependency>
<dependency>
<groupId>com.alibaba.ververica</groupId>
<artifactId>flink-connector-mysql-cdc</artifactId>
<version>1.4.0</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.75</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>
resources/log4j.properties
log4j.rootLogger=warn,stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d %p [%c] - %m%n
反序列化类:
com/zsoft/flinkcdc/MyDeserializationSchema.java
package com.zsoft.flinkcdc;
import com.alibaba.fastjson.JSONObject;
import com.alibaba.ververica.cdc.debezium.DebeziumDeserializationSchema;
import io.debezium.data.Envelope;
import org.apache.flink.api.common.typeinfo.TypeInformation;
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;
public class MyDeserializationSchema implements DebeziumDeserializationSchema<String> {
@Override
public void deserialize(SourceRecord sourceRecord, Collector<String> collector) 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");
// 获取类型( c -> insert, u -> update)
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);
}
}
jsonObj.put("data", dataJsonObj);
collector.collect(jsonObj.toJSONString());
}
@Override
public TypeInformation<String> getProducedType() {
return TypeInformation.of(String.class);
}
}
主类:
com/zsoft/flinkcdc/FlinkCdcDataStream.java
package com.zsoft.flinkcdc;
import com.alibaba.ververica.cdc.connectors.mysql.MySQLSource;
import com.alibaba.ververica.cdc.connectors.mysql.table.StartupOptions;
import com.alibaba.ververica.cdc.debezium.StringDebeziumDeserializationSchema;
import org.apache.flink.api.common.restartstrategy.RestartStrategies;
import org.apache.flink.runtime.state.filesystem.FsStateBackend;
import org.apache.flink.streaming.api.CheckpointingMode;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.environment.CheckpointConfig;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.source.SourceFunction;
import java.util.Properties;
public class FlinkCdcDataStream {
public static void main(String[] args) throws Exception {
// TODO 1. 准备流处理环境
StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
env.setParallelism(1);
// TODO 2. 开启检查点
// 2.1 开启 Checkpoint
env.enableCheckpointing(5000L, CheckpointingMode.EXACTLY_ONCE);
// 2.2 设置超时时间
env.getCheckpointConfig().setCheckpointTimeout(60000);
// 2.3 指定从 CK 自动重启策略
env.setRestartStrategy(RestartStrategies.fixedDelayRestart(1, 6000L));
// 2.4 设置任务关闭时候保留最后一次 CK 数据
env.getCheckpointConfig().enableExternalizedCheckpoints(CheckpointConfig.ExternalizedCheckpointCleanup.RETAIN_ON_CANCELLATION);
// 2.5 设置状态后端
env.setStateBackend(new FsStateBackend("hdfs://s1:8020/flinkCDC_DS"));
// 2.6 设置访问 HDFS 的用户名
System.setProperty("HADOOP_USER_NAME", "hadoop");
// TODO 3. 创建 Flink-MySQL-CDC 的 Source
Properties props = new Properties();
props.setProperty("scan.startup.mode", "initial");
SourceFunction<String> sourceFunction = MySQLSource.<String>builder()
.hostname("s1")
.port(3306)
.username("root")
.password("123456")
.databaseList("test")
.tableList("test.user_info")
.startupOptions(StartupOptions.earliest())
.debeziumProperties(props)
.deserializer(new MyDeserializationSchema())
.build();
// TODO 4. 使用 CDC Source 从 MySQL 读取数据
DataStreamSource<String> mysqlDS = env.addSource(sourceFunction).setParallelism(1);
// TODO 5. 打印输出
mysqlDS.print();
// TODO 6. 执行任务
env.execute();
}
}
4、打包运行
在 IDEA 中打包项目 package
将生成的 flinkcdc-1.0-SNAPSHOT-jar-with-dependencies.jar 通过 Flink 的 webUI 上传
在 Flink 的 WebUI 中上传 jar 包
Submit New Job 页面点击 + Add New 按钮
上传后的 jar 包下填入:
- Entry Class:com.zsoft.flinkcdc.FlinkCdcDataStream
- Parallelism:1
- Program Arguments:
- Savepoint Path:
点击 ”Submit“ 提交应用
5、测试
此时在 MySQL 中插入如下数据:
mysql> insert into user_info values(null, 'zhangsan', 1, 'zhs','beijing');
mysql> insert into user_info values(null, 'lisi', 1, 'ls','shanghai');
mysql> insert into user_info values(null, 'wangwu', 1, 'ww','wangwu');文章来源:https://www.toymoban.com/news/detail-458724.html
在 Flink 的 webUI 中 Task Managers 中点击项目,在 Stdout 中有输出日志:文章来源地址https://www.toymoban.com/news/detail-458724.html
{"database":"test","data":{"sex":1,"nickname":"zhs","id":1,"addr":"beijing","username":"zhangsan"},"type":"insert","table":"user_info"}
{"database":"test","data":{"sex":1,"nickname":"ls","id":2,"addr":"shanghai","username":"lisi"},"type":"insert","table":"user_info"}
{"database":"test","data":{"sex":1,"nickname":"ww","id":3,"addr":"wangwu","username":"wangwu"},"type":"insert","table":"user_info"}
到了这里,关于FlinkCDC 实时监控 MySQL的文章就介绍完了。如果您还想了解更多内容,请在右上角搜索TOY模板网以前的文章或继续浏览下面的相关文章,希望大家以后多多支持TOY模板网!