"java.io.NotSerializableException: org.apache.spark.streaming.StreamingContext" When execute spark streaming

Question

When i executor spark streaming application on yarn, i continued to receive the following error

Why the error happened and how to solve it ? Any suggestion will help, thank you~

15/05/07 11:11:50 INFO dstream.StateDStream: Marking RDD 2364 for time 1430968310000 ms for checkpointing
    15/05/07 11:11:50 INFO scheduler.JobScheduler: Added jobs for time 1430968310000 ms
    15/05/07 11:11:50 INFO scheduler.JobGenerator: Checkpointing graph for time 1430968310000 ms
    15/05/07 11:11:50 INFO streaming.DStreamGraph: Updating checkpoint data for time 1430968310000 ms
    15/05/07 11:11:50 INFO streaming.DStreamGraph: Updated checkpoint data for time 1430968310000 ms
    15/05/07 11:11:50 ERROR actor.OneForOneStrategy: org.apache.spark.streaming.StreamingContext
    java.io.NotSerializableException: org.apache.spark.streaming.StreamingContext
            at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1184)
            at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
            at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
            at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
            at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
            at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
            at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
            at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
            at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
            at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1548)
            at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1509)
            at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
            at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)

The spark streaming application code as follow, i execute it in spark-shell

    import kafka.cluster.Cluster
import kafka.serializer.StringDecoder
import org.apache.spark.storage.StorageLevel
import org.apache.spark.streaming.kafka.KafkaUtils
import org.apache.spark.streaming.{Duration, StreamingContext}
import org.apache.spark.rdd.RDD
import org.apache.spark.streaming.StreamingContext._

val updateFunc = (values: Seq[Int], state: Option[Int]) => {
  Some(0)
}

val ssc = new StreamingContext(sc,
  new Duration(5000))
ssc.checkpoint(".")

val lines = KafkaUtils.createStream(ssc, "10.1.10.21:2181", "kafka_spark_streaming", Map("hello_test" -> 3))

val uuidDstream = lines.transform(rdd => rdd.map(_._2)).map(x => (x, 1)).updateStateByKey[Int](updateFunc)
uuidDstream.count().print()

ssc.start()
ssc.awaitTermination()

Answer 1

The reference to val updateFunc used within the closure of updateStateByKey is pulling the rest of that instance into the closure and taking the StreamingContext with it.

Two options:

• Quick fix: Declare streaming context transient => @transient val ssc= ... Also a good idea to annotate the dstream declarations as @transient as well.
• A better fix: Put your functions in a separate object

Like this:

case object TransformFunctions {
    val updateFunc = ???
}