FlinkSQL消费Kafka写入Hive表

环境版本:

hadoop-3.1.0

hive-3.1.2

flink-1.13.2

一、开发

Maven引入依赖项:


      org.apache.flink
      flink-java
      ${flink.version}

      org.apache.flink
      flink-streaming-java_${scala.binary.version}
      ${flink.version}

      org.apache.flink
      flink-table-planner-blink_${scala.binary.version}
      ${flink.version}

      org.apache.flink
      flink-table-api-java-bridge_2.11
      ${flink.version}

      org.apache.flink
      flink-connector-kafka_2.11
      ${flink.version}

      org.apache.flink
      flink-connector-hive_2.11
      ${flink.version}

      org.apache.flink
      flink-statebackend-rocksdb_2.11
      ${flink.version}

      org.apache.flink
      flink-streaming-scala_2.11
      ${flink.version}

      org.apache.flink
      flink-clients_2.11
      ${flink.version}

      org.apache.hive
      hive-exec
      ${hive.version}

      org.apache.flink
      flink-parquet_2.11
      ${flink.version}

      org.apache.flink
      flink-avro
      ${flink.version}

java代码示例:

package teld;

import org.apache.flink.api.common.eventtime.WatermarkStrategy;
import org.apache.flink.api.common.functions.MapFunction;
import org.apache.flink.api.common.serialization.SimpleStringSchema;
import org.apache.flink.connector.kafka.source.KafkaSource;
import org.apache.flink.connector.kafka.source.enumerator.initializer.OffsetsInitializer;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.datastream.DataStreamSource;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.table.api.EnvironmentSettings;
import org.apache.flink.table.api.SqlDialect;
import org.apache.flink.table.api.bridge.java.StreamTableEnvironment;
import org.apache.flink.table.catalog.hive.HiveCatalog;
import java.time.Duration;

/**
 * @Auther: lixz
 * @Date: 2022/10/13/9:38
 * @Description:  有hive依赖冲突问题暂停
 */
public class Kafka2Hive {
    public static void main( String[] args ) throws Exception {
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        EnvironmentSettings settings = EnvironmentSettings.newInstance().useBlinkPlanner().build();
        StreamTableEnvironment tEnv = StreamTableEnvironment.create(env,settings);
        /**
         * hive环境
         */
//        System.setProperty("HADOOP_USER_NAME","hdfs");
        String name            = "myhive";
        String defaultDatabase = "test";
        //这里版本号一定要与hive-exec包版本一致,否则报错:NoSuchMethodException: org.apache.hadoop.hive.metastore.RetryingMetaStoreClient.getProxy(org.apache.hadoop.hive.conf.HiveConf)
        String hive_version = "3.1.2";
        String hiveConfDir     = "/opt/hive-3.1.2/conf";
        HiveCatalog hive = new HiveCatalog(name, defaultDatabase, hiveConfDir,hive_version);
        tEnv.registerCatalog("myhive", hive);
        tEnv.useCatalog("myhive");
        tEnv.getConfig().setSqlDialect(SqlDialect.HIVE);
        //接入kafka
        KafkaSource source = KafkaSource.builder()
                .setBootstrapServers("192.168.78.1:9092")
                .setTopics("test4")
                .setGroupId("my-group")
                .setStartingOffsets(OffsetsInitializer.latest())
                .setValueOnlyDeserializer(new SimpleStringSchema())
                .build();
        //接入kafka流
        DataStreamSource stream = env.fromSource(source,
                WatermarkStrategy.forBoundedOutOfOrderness(Duration.ofSeconds(5)), "Kafka Source");
        DataStream dataStream = stream.map(new MapFunction() {
            @Override
            public MyUser map(String s) throws Exception {
                String[] arr = s.split(",");
                return new MyUser(arr[0], arr[1], Integer.valueOf(arr[2]));
            }
        }).returns(MyUser.class);
        //创建动态表
        tEnv.createTemporaryView("MyUser",dataStream);
        //创建hive表(如果hive中该表不存在会自动在hive上创建,也可以提前在hive中建好该表,flinksql中就无需再执行建表SQL,因为用了hive的catalog,flinksql运行时会找到表)
        tEnv.executeSql("CREATE TABLE IF NOT EXISTS myhive.test.useroplog \n" +
                "(\n" +
                "ID STRING,\n" +
                "NAME STRING,\n" +
                "AGE INT\n" +
                ") \n" +
                "partitioned by(DAY STRING)\n" +
                "STORED AS parquet TBLPROPERTIES(\n" +
                //小文件自动合并,1.12版的新特性,解决了实时写hive产生的小文件问题
                "'auto-compaction'='true',\n" +
                //合并后的最大文件大小
                "'compaction.file-size'='128MB',\n"+
                "'format' = 'parquet',\n"+
                //压缩方式
                "'parquet.compression'='GZIP',\n"+
                //如果每小时一个分区,这个参数可设置为1 h,这样意思就是说数据延后一小时写入hdfs,能够达到数据的真确性,如果分区是天,这个参数也没必要设置了,今天的数据明天才能写入,时效性太差
                "'sink.partition-commit.delay'='30 s',\n" +
                //metastore值是专门用于写入hive的,也需要指定success-file
                //这样检查点触发完数据写入磁盘后会创建_SUCCESS文件以及hive metastore上创建元数据,这样hive才能够对这些写入的数据可查
                "'sink.partition-commit.policy.kind'='metastore,success-file'\n" +
                ")");
        //写hive表
        tEnv.getConfig().setSqlDialect(SqlDialect.DEFAULT);
        tEnv.executeSql("insert into useroplog select *,'2022-10-13' as DAY from MyUser");
        //打印
//        tEnv.executeSql("select * from MyUser").print();
        env.execute();
    }
}

如果要输出的hive没有创建,执行任务后会自动创建,我们到hive下看看自定创建出来的表格式是什么样:

CREATE TABLE useroplog(
  id string,
  name string,
  age int)
PARTITIONED BY (
  day string)
ROW FORMAT SERDE
  'org.apache.hadoop.hive.ql.io.parquet.serde.ParquetHiveSerDe'
STORED AS INPUTFORMAT
  'org.apache.hadoop.hive.ql.io.parquet.MapredParquetInputFormat'
OUTPUTFORMAT
  'org.apache.hadoop.hive.ql.io.parquet.MapredParquetOutputFormat'
LOCATION
  'hdfs://dss0:8020/user/hive/warehouse/test.db/useroplog'
TBLPROPERTIES (
  'auto-compaction'='true',
  'bucketing_version'='2',
  'format'='parquet',
  'parquet.compression'='GZIP',
  'sink.partition-commit.delay'='1min',
  'sink.partition-commit.policy.kind'='success-file',
  'transient_lastDdlTime'='1665629249')

打包代码,注意不要包含依赖避免依赖重读,我们用到的依赖都放到集群上

提交作业:

flink run-application \
-t yarn-application \
-c teld.Kafka2Hive \
-Dyarn.provided.lib.dirs=”hdfs://dss0:8020/user/flink/flink-dependency-1.13.2;hdfs://dss0:8020/user/flink/flink-dependency-1.13.2/lib;hdfs://dss0:8020/user/flink/flink-dependency-1.13.2/plugin
s” -Dyarn.application.name=flink2hivetest \
flink2hivetest-1.0-SNAPSHOT.jar \

提交成功截图:

FlinkSQL消费Kafka写入Hive表

当我们向kafka发送数据后就会写入到hive中,我们看下hive表生成的文件结构

FlinkSQL消费Kafka写入Hive表

实时写入时,分区会自动创建;我们来查询下

FlinkSQL消费Kafka写入Hive表

二、注意事项

FlinkSQL消费Kafka写入Hive表

2、集群HDFS上的依赖如下:

FlinkSQL消费Kafka写入Hive表

3、hive要开启metastore

bin/hive –service metastore >/dev/null 2>&1 &

开启后可以看9083端口是否存在

4、hive-site.xml配置

需要指定metastore uri

Original: https://blog.csdn.net/qq_32068809/article/details/127297115
Author: 头顶榴莲树
Title: FlinkSQL消费Kafka写入Hive表

原创文章受到原创版权保护。转载请注明出处:https://www.johngo689.com/816933/

转载文章受原作者版权保护。转载请注明原作者出处!

(0)

大家都在看

亲爱的 Coder【最近整理,可免费获取】👉 最新必读书单  | 👏 面试题下载  | 🌎 免费的AI知识星球