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From Haoming Zhang <haoming.zh...@outlook.com>
Subject RE: Partition Key Cannot be Send Out by Producer
Date Fri, 21 Nov 2014 01:53:34 GMT
Hi Joe,

I just tried, it works! Now I should to think how to design the partition function.

Thanks!
Haoming

> Date: Thu, 20 Nov 2014 20:44:29 -0500
> Subject: Re: Partition Key Cannot be Send Out by Producer
> From: joe.stein@stealth.ly
> To: users@kafka.apache.org
> 
> Yes, that was what I was thinking, you don't need to set the serializer
> class if you want Array[byte] that is the default. Remove the line
> c.put("key.serializer.class",
> "kafka.serializer.StringEncoder") you should either see it work or have to
> work through the next issue, hopefully the former =8^)
> 
> /*******************************************
>  Joe Stein
>  Founder, Principal Consultant
>  Big Data Open Source Security LLC
>  http://www.stealth.ly
>  Twitter: @allthingshadoop <http://www.twitter.com/allthingshadoop>
> ********************************************/
> 
> On Thu, Nov 20, 2014 at 8:42 PM, Haoming Zhang <haoming.zhang@outlook.com>
> wrote:
> 
> > Hi Joe,
> >
> > You remind me, maybe I included the incorrect serializer.
> >
> > Here is how I created the producer:
> >       And(s"a synchronous Kafka producer app that writes to the topic
> > $inputTopic")
> >       val producerApp = {
> >         val config = {
> >           val c = new Properties
> >           c.put("producer.type", "sync")
> >           c.put("client.id", "kafka-spark-streaming-test-sync-producer")
> >           c.put("request.required.acks", "1")
> >           c.put("key.serializer.class", "kafka.serializer.StringEncoder")
> >           c
> >         }
> >         kafkaZkCluster.createProducer(inputTopic.name, config).get
> >       }
> >
> > I have included the "key.serializer.class", but I'm not sure whether I did
> > correct..
> >
> > The following is the error message:
> >
> > 14/11/20 17:08:11 INFO KafkaSparkStreamingSpec: Synchronously sending
> > Tweet {"username": "ANY_USER_1", "text": "ANY_TEXT_1", "timestamp":
> > 1416532086} to topic Some(testingInput)
> > [B@3eb78a85
> > KeyedMessage(testingInput,[B@3eb78a85,[B@3eb78a85,[B@3bf54b00)
> > msg.key: [B@3eb78a85
> > msg.message: [B@3bf54b00
> > msg.partKey: [B@3eb78a85
> > msg.topic: testingInput
> > java.lang.ClassCastException: [B cannot be cast to java.lang.String
> >     at kafka.serializer.StringEncoder.toBytes(Encoder.scala:46)
> >     at
> > kafka.producer.async.DefaultEventHandler$$anonfun$serialize$1.apply(DefaultEventHandler.scala:128)
> >     at
> > kafka.producer.async.DefaultEventHandler$$anonfun$serialize$1.apply(DefaultEventHandler.scala:125)
> >     at
> > scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244)
> >     at
> > scala.collection.TraversableLike$$anonfun$map$1.apply(TraversableLike.scala:244)
> >     at
> > scala.collection.IndexedSeqOptimized$class.foreach(IndexedSeqOptimized.scala:33)
> >     at scala.collection.mutable.WrappedArray.foreach(WrappedArray.scala:34)
> >     at
> > scala.collection.TraversableLike$class.map(TraversableLike.scala:244)
> >     at scala.collection.AbstractTraversable.map(Traversable.scala:105)
> >     at
> > kafka.producer.async.DefaultEventHandler.serialize(DefaultEventHandler.scala:125)
> >     at
> > kafka.producer.async.DefaultEventHandler.handle(DefaultEventHandler.scala:52)
> >     at kafka.producer.Producer.send(Producer.scala:76)
> >     at com.cisco.npa.kafka.KafkaProducerApp.send(KafkaProducerApp.scala:87)
> >     at
> > com.cisco.npa.spark.KafkaSparkStreamingSpec$$anonfun$1$$anonfun$apply$mcV$sp$1$$anonfun$apply$mcV$sp$3.apply(KafkaSparkStreamingSpec.scala:171)
> >     at
> > com.cisco.npa.spark.KafkaSparkStreamingSpec$$anonfun$1$$anonfun$apply$mcV$sp$1$$anonfun$apply$mcV$sp$3.apply(KafkaSparkStreamingSpec.scala:153)
> >     at scala.collection.immutable.List.foreach(List.scala:318)
> >     at
> > com.cisco.npa.spark.KafkaSparkStreamingSpec$$anonfun$1$$anonfun$apply$mcV$sp$1.apply$mcV$sp(KafkaSparkStreamingSpec.scala:153)
> >     at
> > com.cisco.npa.spark.KafkaSparkStreamingSpec$$anonfun$1$$anonfun$apply$mcV$sp$1.apply(KafkaSparkStreamingSpec.scala:117)
> >     at
> > com.cisco.npa.spark.KafkaSparkStreamingSpec$$anonfun$1$$anonfun$apply$mcV$sp$1.apply(KafkaSparkStreamingSpec.scala:117)
> >     at
> > org.scalatest.Transformer$$anonfun$apply$1.apply$mcV$sp(Transformer.scala:22)
> >     at org.scalatest.OutcomeOf$class.outcomeOf(OutcomeOf.scala:85)
> >     at org.scalatest.OutcomeOf$.outcomeOf(OutcomeOf.scala:104)
> >     at org.scalatest.Transformer.apply(Transformer.scala:22)
> >     at org.scalatest.Transformer.apply(Transformer.scala:20)
> >     at
> > org.scalatest.FeatureSpecLike$$anon$1.apply(FeatureSpecLike.scala:199)
> >     at org.scalatest.Suite$class.withFixture(Suite.scala:1122)
> >     at org.scalatest.FeatureSpec.withFixture(FeatureSpec.scala:1836)
> >     at
> > org.scalatest.FeatureSpecLike$class.invokeWithFixture$1(FeatureSpecLike.scala:196)
> >     at
> > org.scalatest.FeatureSpecLike$$anonfun$runTest$1.apply(FeatureSpecLike.scala:208)
> >     at
> > org.scalatest.FeatureSpecLike$$anonfun$runTest$1.apply(FeatureSpecLike.scala:208)
> >     at org.scalatest.SuperEngine.runTestImpl(Engine.scala:306)
> >     at
> > org.scalatest.FeatureSpecLike$class.runTest(FeatureSpecLike.scala:208)
> >     at com.cisco.npa.spark.KafkaSparkStreamingSpec.org
> > $scalatest$BeforeAndAfterEach$$super$runTest(KafkaSparkStreamingSpec.scala:35)
> >     at
> > org.scalatest.BeforeAndAfterEach$class.runTest(BeforeAndAfterEach.scala:255)
> >     at
> > com.cisco.npa.spark.KafkaSparkStreamingSpec.runTest(KafkaSparkStreamingSpec.scala:35)
> >     at
> > org.scalatest.FeatureSpecLike$$anonfun$runTests$1.apply(FeatureSpecLike.scala:267)
> >     at
> > org.scalatest.FeatureSpecLike$$anonfun$runTests$1.apply(FeatureSpecLike.scala:267)
> >     at
> > org.scalatest.SuperEngine$$anonfun$traverseSubNodes$1$1.apply(Engine.scala:413)
> >     at
> > org.scalatest.SuperEngine$$anonfun$traverseSubNodes$1$1.apply(Engine.scala:401)
> >     at scala.collection.immutable.List.foreach(List.scala:318)
> >     at org.scalatest.SuperEngine.traverseSubNodes$1(Engine.scala:401)
> >     at org.scalatest.SuperEngine.org
> > $scalatest$SuperEngine$$runTestsInBranch(Engine.scala:390)
> >     at
> > org.scalatest.SuperEngine$$anonfun$traverseSubNodes$1$1.apply(Engine.scala:427)
> >     at
> > org.scalatest.SuperEngine$$anonfun$traverseSubNodes$1$1.apply(Engine.scala:401)
> >     at scala.collection.immutable.List.foreach(List.scala:318)
> >     at org.scalatest.SuperEngine.traverseSubNodes$1(Engine.scala:401)
> >     at org.scalatest.SuperEngine.org
> > $scalatest$SuperEngine$$runTestsInBranch(Engine.scala:396)
> >     at org.scalatest.SuperEngine.runTestsImpl(Engine.scala:483)
> >     at
> > org.scalatest.FeatureSpecLike$class.runTests(FeatureSpecLike.scala:267)
> >     at org.scalatest.FeatureSpec.runTests(FeatureSpec.scala:1836)
> >     at org.scalatest.Suite$class.run(Suite.scala:1424)
> >     at org.scalatest.FeatureSpec.org
> > $scalatest$FeatureSpecLike$$super$run(FeatureSpec.scala:1836)
> >     at
> > org.scalatest.FeatureSpecLike$$anonfun$run$1.apply(FeatureSpecLike.scala:309)
> >     at
> > org.scalatest.FeatureSpecLike$$anonfun$run$1.apply(FeatureSpecLike.scala:309)
> >     at org.scalatest.SuperEngine.runImpl(Engine.scala:545)
> >     at org.scalatest.FeatureSpecLike$class.run(FeatureSpecLike.scala:309)
> >     at org.scalatest.FeatureSpec.run(FeatureSpec.scala:1836)
> >     at org.scalatest.tools.SuiteRunner.run(SuiteRunner.scala:55)
> >     at
> > org.scalatest.tools.Runner$$anonfun$doRunRunRunDaDoRunRun$3.apply(Runner.scala:2563)
> >     at
> > org.scalatest.tools.Runner$$anonfun$doRunRunRunDaDoRunRun$3.apply(Runner.scala:2557)
> >     at scala.collection.immutable.List.foreach(List.scala:318)
> >     at org.scalatest.tools.Runner$.doRunRunRunDaDoRunRun(Runner.scala:2557)
> >     at
> > org.scalatest.tools.Runner$$anonfun$runOptionallyWithPassFailReporter$2.apply(Runner.scala:1044)
> >     at
> > org.scalatest.tools.Runner$$anonfun$runOptionallyWithPassFailReporter$2.apply(Runner.scala:1043)
> >     at
> > org.scalatest.tools.Runner$.withClassLoaderAndDispatchReporter(Runner.scala:2722)
> >     at
> > org.scalatest.tools.Runner$.runOptionallyWithPassFailReporter(Runner.scala:1043)
> >     at org.scalatest.tools.Runner$.main(Runner.scala:860)
> >     at org.scalatest.tools.Runner.main(Runner.scala)
> >     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
> >     at
> > sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
> >     at
> > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
> >     at java.lang.reflect.Method.invoke(Method.java:606)
> >     at
> > scala.tools.eclipse.scalatest.launching.ScalaTestLauncher$.main(ScalaTestLauncher.scala:58)
> >     at
> > scala.tools.eclipse.scalatest.launching.ScalaTestLauncher.main(ScalaTestLauncher.scala)
> >
> > Thanks,
> > Haoming
> >
> > > Date: Thu, 20 Nov 2014 20:29:44 -0500
> > > Subject: Re: Partition Key Cannot be Send Out by Producer
> > > From: joe.stein@stealth.ly
> > > To: users@kafka.apache.org
> > >
> > > iI would helpful to see the full stack trace. Also, how have you
> > > instantiated your Producer class? Did you set a value for
> > > "serializer.class" in the property?
> > >
> > > /*******************************************
> > >  Joe Stein
> > >  Founder, Principal Consultant
> > >  Big Data Open Source Security LLC
> > >  http://www.stealth.ly
> > >  Twitter: @allthingshadoop <http://www.twitter.com/allthingshadoop>
> > > ********************************************/
> > >
> > > On Thu, Nov 20, 2014 at 8:15 PM, Haoming Zhang <
> > haoming.zhang@outlook.com>
> > > wrote:
> > >
> > > > Hi Harsha,
> > > >
> > > > I just tried to hard code a string message, then convert the message to
> > > > byte array, but no lucky...
> > > >
> > > > The following is how my program works:
> > > >
> > > > Create a hardcode key, which is String, then convert to byte array,
> > > > iterate a network message, send the message one by one:
> > > >       networkelements foreach {
> > > >         case networkelement =>
> > > >           val bytes = Injection(networkelement)
> > > >           logger.info(s"Synchronously sending Tweet $networkelement to
> > > > topic ${producerApp.defaultTopic}")
> > > >
> > > >           val hardKey = "2"
> > > >           val parkey = hardKey.getBytes("UTF8")
> > > >           val topic = producerApp.defaultTopic
> > > >           producerApp.send(parkey, bytes, topic)
> > > >       }
> > > >
> > > >
> > > > Here is how the networkelements created, where NetworkElement is a
> > class
> > > > that created by avro, I think you can ignore it:
> > > > val networkelements = fixture.messages
> > > >
> > > >   val fixture = {
> > > >     val BeginningOfEpoch = 0.seconds
> > > >     val AnyTimestamp = 1234.seconds
> > > >     val now = System.currentTimeMillis().millis
> > > >
> > > >     new {
> > > >       val t1 = new NetworkElement("ANY_USER_1", "ANY_TEXT_1",
> > > > now.toSeconds)
> > > >       val t2 = new NetworkElement("ANY_USER_2", "ANY_TEXT_2",
> > > > BeginningOfEpoch.toSeconds)
> > > >       val t3 = new NetworkElement("ANY_USER_3", "ANY_TEXT_3",
> > > > AnyTimestamp.toSeconds)
> > > >
> > > >       val messages = Seq(t1, t2, t3)
> > > >     }
> > > >   }
> > > >
> > > > BTW, I defined the Key and Val types as following:
> > > >
> > > >   type Key = Array[Byte]
> > > >   type Val = Array[Byte]
> > > >
> > > > Thanks,
> > > > Haoming
> > > >
> > > > > From: kafka@harsha.io
> > > > > To: users@kafka.apache.org
> > > > > Subject: Re: Partition Key Cannot be Send Out by Producer
> > > > > Date: Thu, 20 Nov 2014 16:59:19 -0800
> > > > >
> > > > > also the (key: Key, value: Val, topic: Option[String]) "value"
> > should be
> > > > > a string converted to a byte array.
> > > > > Can you send a example of your key and value data.
> > > > >
> > > > >
> > > > > On Thu, Nov 20, 2014, at 04:53 PM, Haoming Zhang wrote:
> > > > > > Hi Harsha,
> > > > > >
> > > > > > Thanks for suggestion!
> > > > > >
> > > > > > I have checked this link before, and I tried to create the
> > partition
> > > > key
> > > > > > like the following:
> > > > > >           val hardKey = "2"
> > > > > >           val parkey = hardKey.getBytes("UTF8")
> > > > > >
> > > > > > But I still get the same exception. I also tried set "UTF8"
as
> > "UTF-8",
> > > > > > but no luck...
> > > > > >
> > > > > > Regards,
> > > > > > Haoming
> > > > > >
> > > > > > > From: kafka@harsha.io
> > > > > > > To: users@kafka.apache.org
> > > > > > > Subject: Re: Partition Key Cannot be Send Out by Producer
> > > > > > > Date: Thu, 20 Nov 2014 16:43:11 -0800
> > > > > > >
> > > > > > > Hi Haoming,
> > > > > > >           Take a look at the code here
> > > > > > >
> > > >
> > https://github.com/stealthly/scala-kafka/blob/master/src/main/scala/KafkaProducer.scala
> > > > > > > for your partKey it should be string and when you converting
it
> > into
> > > > > > > byte array you can use partKey.getBytes("UTF8")
> > > > > > > -Harsha
> > > > > > >
> > > > > > > On Thu, Nov 20, 2014, at 03:57 PM, Haoming Zhang wrote:
> > > > > > > > Hi all,
> > > > > > > >
> > > > > > > > I'm a beginner of Kafka, currently I'm stuck by how
to send
> > out a
> > > > > > > > KeyedMessage by producer. I would like to design a
partition
> > > > > > > > function to route the message based on the key, but
the
> > producer
> > > > cannot
> > > > > > > > send the KeyedMessage and I got this exception:
> > > > > > > > java.lang.ClassCastException: [B cannot be cast to
> > java.lang.String
> > > > > > > >
> > > > > > > > What I tried is hardcode a partition key ( I tried
String and
> > > > Integer,
> > > > > > > > currently it is Integer ), then convert the partition
key to
> > Byte
> > > > Array:
> > > > > > > >           val converter = new DataTypeConvertion
> > > > > > > >           val hardKey = 2
> > > > > > > >           val partkey = converter.intToByteArray(hardKey)
> > > > > > > >
> > > > > > > >  Then create a KeyedMessage by the following function:
> > > > > > > >
> > > > > > > >   private def toMessage(value: Val, key: Option[Key]
= None,
> > topic:
> > > > > > > >   Option[String] = None): KeyedMessage[Key, Val] =
{
> > > > > > > >     val t = topic.get
> > > > > > > >     require(!t.isEmpty, "Topic must not be empty")
> > > > > > > >     key match {
> > > > > > > >       case Some(key) => new KeyedMessage(t, key,
value)
> > > > > > > >       case _ => new KeyedMessage(t, value)
> > > > > > > >     }
> > > > > > > >   }
> > > > > > > >
> > > > > > > > Then try to send the KeyedMessage by a Kafka producer:
> > > > > > > >
> > > > > > > >   def send(key: Key, value: Val, topic: Option[String]
= None)
> > {
> > > > > > > >     val msg = toMessage(value, Option(key), topic)
> > > > > > > >     print(msg + "\n")
> > > > > > > >     print("msg.key" + msg.key + "\n")
> > > > > > > >     print("msg.message" + msg.message + "\n")
> > > > > > > >     print("msg.partKey" + msg.partKey + "\n")
> > > > > > > >     print("msg.topic" + msg.topic + "\n")
> > > > > > > >     try {
> > > > > > > >       p.send(msg) //P is an instance of producer,
exception
> > > > happens in
> > > > > > > >       this line
> > > > > > > >     } catch {
> > > > > > > >       case e: Exception =>
> > > > > > > >         e.printStackTrace()
> > > > > > > >         System.exit(1)
> > > > > > > >     }
> > > > > > > >   }
> > > > > > > >
> > > > > > > > As you can see, I added many print statement in the
above
> > > > function, and
> > > > > > > > the following is the output of above function:
> > > > > > > > KeyedMessage(testingInput,[B@7ad40950,[B@7ad40950,[B@7ce18764)
> > > > > > > > msg.key: [B@7ad40950
> > > > > > > > msg.message: [B@7ce18764
> > > > > > > > msg.partKey: [B@7ad40950
> > > > > > > > msg.topic: testingInput
> > > > > > > >
> > > > > > > > The key of KeyedMessage is displayed as [B@7ad40950
, I think
> > it
> > > > is a
> > > > > > > > memory address and the exception
> > (java.lang.ClassCastException: [B
> > > > cannot
> > > > > > > > be cast to java.lang.String) happens when "send" function
try
> > to
> > > > convert
> > > > > > > > the Byte Array to String.
> > > > > > > >
> > > > > > > > Am I wrong on creating a key in Byte Array type?
> > > > > > > > Some examples of how to use KeyedMessage will be great!
> > > > > > > >
> > > > > > > > Regards,
> > > > > > > > Haoming
> > > > > > > >
> > > > > > > >
> > > > > >
> > > >
> > > >
> >
> >
 		 	   		  
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