Flink DataStream之输出数据到File中

news2024/12/23 21:07:31

新建类

package test01;

import org.apache.flink.api.common.serialization.SimpleStringEncoder;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.configuration.MemorySize;
import org.apache.flink.connector.file.sink.FileSink;
import org.apache.flink.core.fs.Path;
import org.apache.flink.streaming.api.CheckpointingMode;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.sink.filesystem.OutputFileConfig;
import org.apache.flink.streaming.api.functions.sink.filesystem.rollingpolicies.DefaultRollingPolicy;

import java.time.Duration;

public class TestOutputFile {

    public static void main(String[] args) throws Exception {
        StreamExecutionEnvironment executionEnvironment = StreamExecutionEnvironment.getExecutionEnvironment(new Configuration());
        executionEnvironment.setParallelism(1);

        //监听数据端口
        DataStreamSource<String> dataSource = executionEnvironment.socketTextStream("localhost", 9999);

        //开启checkpoint,这样到了一定节点就会关闭文件，否则文件一直都是inprogress,此处设置的检查点是2秒。
        executionEnvironment.enableCheckpointing(2000, CheckpointingMode.EXACTLY_ONCE);

        //输出至文件
        FileSink<String> fileSink = FileSink
                //设置按行输出，指定输出的路径及编码格式，这里的泛型指定的是字符串类型。
                .<String>forRowFormat(new Path("D:/IT/testfilnk"), new SimpleStringEncoder<>("UTF-8"))
                //设置输出文件名的前缀和后缀
                .withOutputFileConfig(OutputFileConfig.builder()
                        .withPartPrefix("test-flink-output-")
                        .withPartSuffix(".log")
                        .build())
                //设置文件滚动策略,这里设置的是20s和1024B(1KB)，滚动策略满足其一就会重新写新文件。
                .withRollingPolicy(
                        DefaultRollingPolicy.builder()
                                .withRolloverInterval(Duration.ofSeconds(20))
                                .withMaxPartSize(new MemorySize(1024))
                                .build()
                )
                .build();

        dataSource.sinkTo(fileSink);
        executionEnvironment.execute();
    }
}