1. 聲明
目前内容主要為測試和使用Flink,将資料讀取處理後放入到kafka的topic中
主要内容:
- 使用Flink讀取文本内容
- 過濾讀取的内容
- 将讀取的内容放入kafka中
2.基本demo
1.pom依賴
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<flink.version>1.13.0</flink.version>
<target.java.version>1.8</target.java.version>
<scala.binary.version>2.11</scala.binary.version>
<maven.compiler.source>${target.java.version}</maven.compiler.source>
<maven.compiler.target>${target.java.version}</maven.compiler.target>
<log4j.version>2.12.1</log4j.version>
</properties>
<dependencies>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-walkthrough-common_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
</dependency>
<!-- This dependency is provided, because it should not be packaged into
the JAR file. -->
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-streaming-java_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
<!-- <scope>provided</scope> -->
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-clients_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
<!-- <scope>provided</scope> -->
</dependency>
<!-- 直接導入需要的flink到kafka的連接配接器 -->
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-connector-kafka_2.12</artifactId>
<version>1.13.0</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-slf4j-impl</artifactId>
<version>${log4j.version}</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-api</artifactId>
<version>${log4j.version}</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
<version>${log4j.version}</version>
<scope>runtime</scope>
</dependency>
</dependencies>
2.開啟一個指令行消費者
![](https://img.laitimes.com/img/_0nNw4CM6IyYiwiM6ICdiwiIyVGduV2YfNWawNyZuBnL1YjN1QTOzQTMzITNwEjMwIzLc52YucWbp5GZzNmLn9Gbi1yZtl2Lc9CX6MHc0RHaiojIsJye.png)
3.開始編寫demo
import java.util.Properties;
import org.apache.flink.api.common.JobExecutionResult;
import org.apache.flink.api.common.functions.FilterFunction;
import org.apache.flink.api.common.serialization.SimpleStringSchema;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.connectors.kafka.FlinkKafkaProducer;
/**
*
* @author hy
* @createTime 2021-05-23 10:38:40
* @description 目前内容主要将Apache Flink中處理的内容放入目前的Apache Kafka中(将Kafka作為資料輸出的地點)
*
*/
public class LocalRunningToKafkaSaveTest {
public static void main(String[] args) {
// 采用本地模式
StreamExecutionEnvironment env = StreamExecutionEnvironment.createLocalEnvironment();
// 設定資料來源為集合資料
String topic = "test-events"; // 設定監聽的主題
Properties props = new Properties();
props.setProperty("bootstrap.servers", "192.168.1.101:9092");
props.setProperty("group.id", "test");
String filePath = "D:\\eclipse-workspace\\Apache-Flink-Start\\resources\\abc.txt";
DataStream<String> txtStream = env.readTextFile(filePath);
// 這裡可以進行處理操作(但是結果需要指派)
txtStream = txtStream.filter(new FilterFunction<String>() {
@Override
public boolean filter(String value) throws Exception {
// TODO Auto-generated method stub
// 傳回資料中不帶有19的資料
if(!value.contains("19")) {
return true;
}
return false;
}
});
System.out.println("處理後的資料=====>");
txtStream.print();
System.out.println("<=====處理後的資料");
// 将讀取的文本類型的資料注入到kafka的這個topic中
FlinkKafkaProducer<String> producer=new FlinkKafkaProducer<String>(topic, new SimpleStringSchema(),props);
txtStream.addSink(producer);
System.out.println("将目前的資料處理後放入kafka的test-events這個topic成功!");
try {
// 最後開始執行
JobExecutionResult result = env.execute("Fraud Detection");
if (result.isJobExecutionResult()) {
System.out.println("執行完畢......");
}
System.out.println();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
小心這裡的filter,以及使用的Sink為FlinkKafkaProducer(一個消息生産者)
3. 測試結果
指令行消費者結果:
4. 總結
1.由于本人沒有找到一個清空topic的消息的,隻要是訂閱了的,以前釋出的消息都會發送,并且接受到,隻有執行删除topic的指令,然後在建立才有用
./bin/kafka-topics.sh --delete --topic test-events --bootstrap-server 192.168.1.101:9092