Hi Dian,
thanks, that did the trick.
Unfortunately, I have a new problem now.
As I said I'm trying to read json data from a kafka topic into a datastream. I
tried doing this using the JsonRowDeserializationSchema-class as below (the
Json-objects are tweets and thus pretty nested and complex). However that
causes the following error:
Traceback (most recent call last):
File "/home/ubuntu/load_kafka.py", line 21, in <module>
env.execute()
File
"/home/ubuntu/flink-1.12.2/opt/python/pyflink.zip/pyflink/datastream/stream_execution_environment.py",
line 623, in execute
File
"/home/ubuntu/flink-1.12.2/opt/python/py4j-0.10.8.1-src.zip/py4j/java_gateway.py",
line 1285, in __call__
File
"/home/ubuntu/flink-1.12.2/opt/python/pyflink.zip/pyflink/util/exceptions.py",
line 147, in deco
File
"/home/ubuntu/flink-1.12.2/opt/python/py4j-0.10.8.1-src.zip/py4j/protocol.py",
line 326, in get_return_value
py4j.protocol.Py4JJavaError: An error occurred while calling o1.execute.
: java.util.concurrent.ExecutionException:
org.apache.flink.client.program.ProgramInvocationException: Job failed (JobID:
00392ec565588adc82c8dc405fdb9e1d)
at
java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:357)
at java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1908)
at
org.apache.flink.client.program.StreamContextEnvironment.getJobExecutionResult(StreamContextEnvironment.java:123)
at
org.apache.flink.client.program.StreamContextEnvironment.execute(StreamContextEnvironment.java:80)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at
org.apache.flink.api.python.shaded.py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:244)
at
org.apache.flink.api.python.shaded.py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
at org.apache.flink.api.python.shaded.py4j.Gateway.invoke(Gateway.java:282)
at
org.apache.flink.api.python.shaded.py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
at
org.apache.flink.api.python.shaded.py4j.commands.CallCommand.execute(CallCommand.java:79)
at
org.apache.flink.api.python.shaded.py4j.GatewayConnection.run(GatewayConnection.java:238)
at java.lang.Thread.run(Thread.java:748)
Caused by: org.apache.flink.client.program.ProgramInvocationException: Job
failed (JobID: 00392ec565588adc82c8dc405fdb9e1d)
at
org.apache.flink.client.deployment.ClusterClientJobClientAdapter.lambda$null$6(ClusterClientJobClientAdapter.java:125)
at
java.util.concurrent.CompletableFuture.uniApply(CompletableFuture.java:616)
at
java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:591)
at
java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:488)
at
java.util.concurrent.CompletableFuture.complete(CompletableFuture.java:1975)
at
org.apache.flink.client.program.rest.RestClusterClient.lambda$pollResourceAsync$22(RestClusterClient.java:665)
at
java.util.concurrent.CompletableFuture.uniWhenComplete(CompletableFuture.java:774)
at
java.util.concurrent.CompletableFuture$UniWhenComplete.tryFire(CompletableFuture.java:750)
at
java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:488)
at
java.util.concurrent.CompletableFuture.complete(CompletableFuture.java:1975)
at
org.apache.flink.runtime.concurrent.FutureUtils.lambda$retryOperationWithDelay$9(FutureUtils.java:394)
at
java.util.concurrent.CompletableFuture.uniWhenComplete(CompletableFuture.java:774)
at
java.util.concurrent.CompletableFuture$UniWhenComplete.tryFire(CompletableFuture.java:750)
at
java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:488)
at
java.util.concurrent.CompletableFuture.postFire(CompletableFuture.java:575)
at
java.util.concurrent.CompletableFuture$UniCompose.tryFire(CompletableFuture.java:943)
at
java.util.concurrent.CompletableFuture$Completion.run(CompletableFuture.java:456)
at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
... 1 more
Caused by: org.apache.flink.runtime.client.JobExecutionException: Job execution
failed.
at
org.apache.flink.runtime.jobmaster.JobResult.toJobExecutionResult(JobResult.java:144)
at
org.apache.flink.client.deployment.ClusterClientJobClientAdapter.lambda$null$6(ClusterClientJobClientAdapter.java:123)
... 19 more
Caused by: org.apache.flink.runtime.JobException: Recovery is suppressed by
NoRestartBackoffTimeStrategy
at
org.apache.flink.runtime.executiongraph.failover.flip1.ExecutionFailureHandler.handleFailure(ExecutionFailureHandler.java:118)
at
org.apache.flink.runtime.executiongraph.failover.flip1.ExecutionFailureHandler.getFailureHandlingResult(ExecutionFailureHandler.java:80)
at
org.apache.flink.runtime.scheduler.DefaultScheduler.handleTaskFailure(DefaultScheduler.java:233)
at
org.apache.flink.runtime.scheduler.DefaultScheduler.maybeHandleTaskFailure(DefaultScheduler.java:224)
at
org.apache.flink.runtime.scheduler.DefaultScheduler.updateTaskExecutionStateInternal(DefaultScheduler.java:215)
at
org.apache.flink.runtime.scheduler.SchedulerBase.updateTaskExecutionState(SchedulerBase.java:669)
at
org.apache.flink.runtime.scheduler.SchedulerNG.updateTaskExecutionState(SchedulerNG.java:89)
at
org.apache.flink.runtime.jobmaster.JobMaster.updateTaskExecutionState(JobMaster.java:447)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at
org.apache.flink.runtime.rpc.akka.AkkaRpcActor.handleRpcInvocation(AkkaRpcActor.java:305)
at
org.apache.flink.runtime.rpc.akka.AkkaRpcActor.handleRpcMessage(AkkaRpcActor.java:212)
at
org.apache.flink.runtime.rpc.akka.FencedAkkaRpcActor.handleRpcMessage(FencedAkkaRpcActor.java:77)
at
org.apache.flink.runtime.rpc.akka.AkkaRpcActor.handleMessage(AkkaRpcActor.java:158)
at akka.japi.pf.UnitCaseStatement.apply(CaseStatements.scala:26)
at akka.japi.pf.UnitCaseStatement.apply(CaseStatements.scala:21)
at scala.PartialFunction$class.applyOrElse(PartialFunction.scala:123)
at akka.japi.pf.UnitCaseStatement.applyOrElse(CaseStatements.scala:21)
at scala.PartialFunction$OrElse.applyOrElse(PartialFunction.scala:170)
at scala.PartialFunction$OrElse.applyOrElse(PartialFunction.scala:171)
at scala.PartialFunction$OrElse.applyOrElse(PartialFunction.scala:171)
at akka.actor.Actor$class.aroundReceive(Actor.scala:517)
at akka.actor.AbstractActor.aroundReceive(AbstractActor.scala:225)
at akka.actor.ActorCell.receiveMessage(ActorCell.scala:592)
at akka.actor.ActorCell.invoke(ActorCell.scala:561)
at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:258)
at akka.dispatch.Mailbox.run(Mailbox.scala:225)
at akka.dispatch.Mailbox.exec(Mailbox.scala:235)
at akka.dispatch.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
at
akka.dispatch.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
at akka.dispatch.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
at
akka.dispatch.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
Caused by: java.io.IOException: Failed to deserialize JSON '
'.
at
org.apache.flink.formats.json.JsonRowDeserializationSchema.deserialize(JsonRowDeserializationSchema.java:149)
at
org.apache.flink.formats.json.JsonRowDeserializationSchema.deserialize(JsonRowDeserializationSchema.java:81)
at
org.apache.flink.api.common.serialization.DeserializationSchema.deserialize(DeserializationSchema.java:82)
at
org.apache.flink.streaming.connectors.kafka.internals.KafkaDeserializationSchemaWrapper.deserialize(KafkaDeserializationSchemaWrapper.java:56)
at
org.apache.flink.streaming.connectors.kafka.internals.KafkaFetcher.partitionConsumerRecordsHandler(KafkaFetcher.java:177)
at
org.apache.flink.streaming.connectors.kafka.internals.KafkaFetcher.runFetchLoop(KafkaFetcher.java:137)
at
org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumerBase.run(FlinkKafkaConsumerBase.java:761)
at
org.apache.flink.streaming.api.operators.StreamSource.run(StreamSource.java:110)
at
org.apache.flink.streaming.api.operators.StreamSource.run(StreamSource.java:66)
at
org.apache.flink.streaming.runtime.tasks.SourceStreamTask$LegacySourceFunctionThread.run(SourceStreamTask.java:263)
Caused by: java.lang.ClassCastException:
org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.MissingNode
cannot be cast to
org.apache.flink.shaded.jackson2.com.fasterxml.jackson.databind.node.ObjectNode
at
org.apache.flink.formats.json.JsonRowDeserializationSchema.lambda$assembleRowConverter$77f7700$1(JsonRowDeserializationSchema.java:518)
at
org.apache.flink.formats.json.JsonRowDeserializationSchema.lambda$wrapIntoNullableConverter$d586c97$1(JsonRowDeserializationSchema.java:266)
at
org.apache.flink.formats.json.JsonRowDeserializationSchema.deserialize(JsonRowDeserializationSchema.java:143)
... 9 more
org.apache.flink.client.program.ProgramAbortException
at org.apache.flink.client.python.PythonDriver.main(PythonDriver.java:124)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at
org.apache.flink.client.program.PackagedProgram.callMainMethod(PackagedProgram.java:349)
at
org.apache.flink.client.program.PackagedProgram.invokeInteractiveModeForExecution(PackagedProgram.java:219)
at org.apache.flink.client.ClientUtils.executeProgram(ClientUtils.java:114)
at
org.apache.flink.client.cli.CliFrontend.executeProgram(CliFrontend.java:812)
at org.apache.flink.client.cli.CliFrontend.run(CliFrontend.java:246)
at
org.apache.flink.client.cli.CliFrontend.parseAndRun(CliFrontend.java:1054)
at
org.apache.flink.client.cli.CliFrontend.lambda$main$10(CliFrontend.java:1132)
at
org.apache.flink.runtime.security.contexts.NoOpSecurityContext.runSecured(NoOpSecurityContext.java:28)
at org.apache.flink.client.cli.CliFrontend.main(CliFrontend.java:1132)
The Json-Objects look like this (modified out of privacy concerns):
{"data":{"text":"xy",
"public_metrics":{"retweet_count":0,"reply_count":0,"like_count":0,"quote_count":0},
"author_id":"123","id":"123","created_at":"00000",
"source":"Twitter for Android","lang":"in"},
"includes":{"users":[{"protected":false,"id":"123",
"name":"nobody","created_at":"000",
"public_metrics":{"followers_count":0,"following_count":0,"tweet_count":557,"listed_count":0},"username":"nobody"}]},
"matching_rules":[{"id":123,"tag":"nothing"}]}
I'm guess that one reason for why my code isn't working could be that I specify
matching_rules":[{"id":123,"tag":"nothing"}]}
as
Types.ROW([Types.ROW([Types.STRING(), Types.STRING()])])
I'm aware that I would need something like Types.ARRAY here, but it seems that
only supports primitive Types as array-elements and not rows.
Given that the JsonRowDeserializationSchema didnt work I have tried to do it
with the SimpleStringSchema as follows:
from pyflink.common.serialization import SimpleStringSchema
from pyflink.common.typeinfo import Types
from pyflink.datastream import StreamExecutionEnvironment
from pyflink.datastream.connectors import FlinkKafkaConsumer
env = StreamExecutionEnvironment.get_execution_environment()
env.set_parallelism(1)
kafka_props = {'bootstrap.servers': 'localhost:9092', 'group.id':
'twitter_consumers'}
kafka_consumer = FlinkKafkaConsumer("twitter-stream", SimpleStringSchema(),
kafka_props)
ds = env.add_source(kafka_consumer)
ds.print()
env.execute()
But this also didn't work, as nothing happens (no output or anything).
Do you have an idea what I'm doing wrong? Or should I maybe open a new thread
for this? Unfortunately, there is very little documentation about this kind of
stuff and how to use it.
Thanks a lot,
Giacomo
Gesendet: Montag, 19. April 2021 um 03:51 Uhr
Von: "Dian Fu" <dian0511...@gmail.com>
An: g.g.m.5...@web.de
Cc: "user" <user@flink.apache.org>
Betreff: Re: PyFlink Kafka-Connector NoClassDefFoundError
Hi,
You need to use the fat jar [1] as documented in the Kafka Table & SQL
connector page [2].
[1]
https://repo.maven.apache.org/maven2/org/apache/flink/flink-sql-connector-kafka_2.11/1.12.2/flink-sql-connector-kafka_2.11-1.12.2.jar
[2]
https://ci.apache.org/projects/flink/flink-docs-release-1.12/dev/table/connectors/kafka.html[https://ci.apache.org/projects/flink/flink-docs-release-1.12/dev/table/connectors/kafka.html]
Regards,
Dian
2021年4月19日 上午1:26，g.g.m.5...@web.de[mailto:g.g.m.5...@web.de] 写道：
Hi,
I am trying to run a very basic job in PyFlink (getting Data from a Kafka-Topic
and printing the stream).
In the command line I run:
./bin/flink run \
--python /home/ubuntu/load_kafka.py \
--jarfile /home/ubuntu/flink-connector-kafka_2.12-1.12.2.jar
I downloaded the jar from:
https://mvnrepository.com/artifact/org.apache.flink/flink-connector-kafka[https://mvnrepository.com/artifact/org.apache.flink/flink-connector-kafka]
Now I get the following error:
File "/home/ubuntu/load_kafka.py", line 16, in <module>
kafka_consumer = FlinkKafkaConsumer("twitter-stream-source",
json_row_schema, kafka_props)
File
"/home/ubuntu/flink-1.12.2/opt/python/pyflink.zip/pyflink/datastream/connectors.py",
line 179, in __init__
File
"/home/ubuntu/flink-1.12.2/opt/python/pyflink.zip/pyflink/datastream/connectors.py",
line 329, in _get_kafka_consumer
File
"/home/ubuntu/flink-1.12.2/opt/python/py4j-0.10.8.1-src.zip/py4j/java_gateway.py",
line 1553, in __call__
File
"/home/ubuntu/flink-1.12.2/opt/python/pyflink.zip/pyflink/util/exceptions.py",
line 147, in deco
File
"/home/ubuntu/flink-1.12.2/opt/python/py4j-0.10.8.1-src.zip/py4j/protocol.py",
line 326, in get_return_value
py4j.protocol.Py4JJavaError: An error occurred while calling
None.org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer.
: java.lang.NoClassDefFoundError:
org/apache/kafka/common/serialization/ByteArrayDeserializer
at
org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer.setDeserializer(FlinkKafkaConsumer.java:322)
at
org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer.<init>(FlinkKafkaConsumer.java:223)
at
org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer.<init>(FlinkKafkaConsumer.java:154)
at
org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer.<init>(FlinkKafkaConsumer.java:139)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at
sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at
org.apache.flink.api.python.shaded.py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:247)
at
org.apache.flink.api.python.shaded.py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:357)
at org.apache.flink.api.python.shaded.py4j.Gateway.invoke(Gateway.java:238)
at
org.apache.flink.api.python.shaded.py4j.commands.ConstructorCommand.invokeConstructor(ConstructorCommand.java:80)
at
org.apache.flink.api.python.shaded.py4j.commands.ConstructorCommand.execute(ConstructorCommand.java:69)
at
org.apache.flink.api.python.shaded.py4j.GatewayConnection.run(GatewayConnection.java:238)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.ClassNotFoundException:
org.apache.kafka.common.serialization.ByteArrayDeserializer
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
at
org.apache.flink.util.FlinkUserCodeClassLoader.loadClassWithoutExceptionHandling(FlinkUserCodeClassLoader.java:64)
at
org.apache.flink.util.ChildFirstClassLoader.loadClassWithoutExceptionHandling(ChildFirstClassLoader.java:74)
at
org.apache.flink.util.FlinkUserCodeClassLoader.loadClass(FlinkUserCodeClassLoader.java:48)
at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
... 15 more
org.apache.flink.client.program.ProgramAbortException
at org.apache.flink.client.python.PythonDriver.main(PythonDriver.java:124)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at
org.apache.flink.client.program.PackagedProgram.callMainMethod(PackagedProgram.java:349)
at
org.apache.flink.client.program.PackagedProgram.invokeInteractiveModeForExecution(PackagedProgram.java:219)
at org.apache.flink.client.ClientUtils.executeProgram(ClientUtils.java:114)
at org.apache.flink.client.cli.CliFrontend.executeProgram(CliFrontend.java:812)
at org.apache.flink.client.cli.CliFrontend.run(CliFrontend.java:246)
at org.apache.flink.client.cli.CliFrontend.parseAndRun(CliFrontend.java:1054)
at org.apache.flink.client.cli.CliFrontend.lambda$main$10(CliFrontend.java:1132)
at
org.apache.flink.runtime.security.contexts.NoOpSecurityContext.runSecured(NoOpSecurityContext.java:28)
at org.apache.flink.client.cli.CliFrontend.main(CliFrontend.java:1132)
I'm thinking that I might be providing the wrong jar, but don't really have any
idea.
This is my code:
from pyflink.common.serialization import JsonRowDeserializationSchema
from pyflink.common.typeinfo import Types
from pyflink.datastream import StreamExecutionEnvironment
from pyflink.datastream.connectors import FlinkKafkaConsumer
env = StreamExecutionEnvironment.get_execution_environment()
env.set_parallelism(1)
type_info = Types.ROW([Types.ROW([Types.STRING(), Types.ROW([Types.INT(),
Types.INT(), Types.INT(), Types.INT()]), Types.STRING(), Types.STRING(),
Types.STRING(), Types.STRING(), Types.STRING()]),
Types.ROW([Types.ROW([Types.ROW([Types.BOOLEAN(), Types.STRING(),
Types.STRING(), Types.STRING(), Types.ROW([Types.INT(), Types.INT(),
Types.INT(), Types.INT()]), Types.STRING()])])]),
Types.ROW([Types.ROW([Types.STRING(), Types.STRING()])])])
json_row_schema =
JsonRowDeserializationSchema.builder().type_info(type_info).build()
kafka_props = {'bootstrap.servers': 'localhost:9092', 'group.id':
'twitter_consumers'}
kafka_consumer = FlinkKafkaConsumer("twitter-stream-source", json_row_schema,
kafka_props)
# research this
kafka_consumer.set_start_from_earliest()
ds = env.add_source(kafka_consumer)
ds.print()
ds.execute()
Thanks a lot!
