I want to write ORC file using Flink's Streaming File Sink but it doesn’t write files correctly - apache-flink

Question

I am reading data from Kafka and trying to write it to the HDFS file system in ORC format. I have used the below link reference from their official website. But I can see that Flink write exact same content for all data and make so many files and all files are ok 103KB
https://ci.apache.org/projects/flink/flink-docs-release-1.11/dev/connectors/streamfile_sink.html#orc-format
Please find my code below.
object BeaconBatchIngest extends StreamingBase {
val env: StreamExecutionEnvironment = StreamExecutionEnvironment.getExecutionEnvironment
def getTopicConfig(configs: List[Config]): Map[String, String] = (for (config: Config <- configs) yield (config.getString("sourceTopic"), config.getString("destinationTopic"))).toMap
def setKafkaConfig():Unit ={
val kafkaParams = new Properties()
kafkaParams.setProperty("bootstrap.servers","")
kafkaParams.setProperty("zookeeper.connect","")
kafkaParams.setProperty("group.id", DEFAULT_KAFKA_GROUP_ID)
kafkaParams.setProperty("auto.offset.reset", "latest")
val kafka_consumer:FlinkKafkaConsumer[String] = new FlinkKafkaConsumer[String]("sourceTopics", new SimpleStringSchema(),kafkaParams)
kafka_consumer.setStartFromLatest()
val stream: DataStream[DataParse] = env.addSource(kafka_consumer).map(new temp)
val schema: String = "struct<_col0:string,_col1:bigint,_col2:string,_col3:string,_col4:string>"
val writerProperties = new Properties()
writerProperties.setProperty("orc.compress", "ZLIB")
val writerFactory = new OrcBulkWriterFactory(new PersonVectorizer(schema),writerProperties,new org.apache.hadoop.conf.Configuration);
val sink: StreamingFileSink[DataParse] = StreamingFileSink
.forBulkFormat(new Path("hdfs://warehousestore/hive/warehouse/metrics_test.db/upp_raw_prod/hour=1/"), writerFactory)
.build()
stream.addSink(sink)
}
def main(args: Array[String]): Unit = {
setKafkaConfig()
env.enableCheckpointing(5000)
env.execute("Kafka_Flink_HIVE")
}
}
class temp extends MapFunction[String,DataParse]{
override def map(record: String): DataParse = {
new DataParse(record)
}
}
class DataParse(data : String){
val parsedJason = parse(data)
val timestamp = compact(render(parsedJason \ "timestamp")).replaceAll("\"", "").toLong
val event = compact(render(parsedJason \ "event")).replaceAll("\"", "")
val source_id = compact(render(parsedJason \ "source_id")).replaceAll("\"", "")
val app = compact(render(parsedJason \ "app")).replaceAll("\"", "")
val json = data
}
class PersonVectorizer(schema: String) extends Vectorizer[DataParse](schema) {
override def vectorize(element: DataParse, batch: VectorizedRowBatch): Unit = {
val eventColVector = batch.cols(0).asInstanceOf[BytesColumnVector]
val timeColVector = batch.cols(1).asInstanceOf[LongColumnVector]
val sourceIdColVector = batch.cols(2).asInstanceOf[BytesColumnVector]
val appColVector = batch.cols(3).asInstanceOf[BytesColumnVector]
val jsonColVector = batch.cols(4).asInstanceOf[BytesColumnVector]
timeColVector.vector(batch.size + 1) = element.timestamp
eventColVector.setVal(batch.size + 1, element.event.getBytes(StandardCharsets.UTF_8))
sourceIdColVector.setVal(batch.size + 1, element.source_id.getBytes(StandardCharsets.UTF_8))
appColVector.setVal(batch.size + 1, element.app.getBytes(StandardCharsets.UTF_8))
jsonColVector.setVal(batch.size + 1, element.json.getBytes(StandardCharsets.UTF_8))
}
}

Answer 1

With bulk formats (such as ORC), the StreamingFileSink rolls over to new files with every checkpoint. If you reduce the checkpointing interval (currently 5 seconds), it won't write so many files.