Skip to content
This repository was archived by the owner on Nov 11, 2022. It is now read-only.
This repository was archived by the owner on Nov 11, 2022. It is now read-only.

Take 2: Error when reading from External Unbounded Source and Write to PubSubIO #589

Description

@cbazza

I took the title from a previous issue #105 that has been resolved and it sounds just like my issue.

I have a pipeline that reads from unbonded pubsubio and writes to pubsubio.
Testing it locally reading from TextIO file and writing to pubsubio, works great, but when I switch the source to pubsubio (with large amount of data) and deploy it to google's dataflow, it runs fine but when data needs to be written out to pubsubio I get the following NullPointerException (seems related to creating the protobuf that wraps the message sent to pubsub):

Using Apache Beam 2.0.0 and the unique thing about my linear pipeline is that it contains 2 different windows. The first one a sliding window and the second a fixed window.

                .apply(Window.<GaugeDebug>into(
                        SlidingWindows.of(windowSizeL1).every(windowOffsetL1)
                        )
                        .triggering(Repeatedly.forever(AfterProcessingTime.pastFirstElementInPane()
                                .plusDelayOf(windowDelayL1)))
                        .accumulatingFiredPanes()
                        .withAllowedLateness(windowLatenessL1)
                );
...
                .apply(Combine.<List<String>, GaugeDebug>perKey(new SumGauges()))
...
                .apply(Count.<List<String>, GaugeDebug>perKey())
...
                .apply(Window.<KV<List<String>,Long>>into(
                        FixedWindows.of(windowSizeL2)
                        ))
...
                .apply(Max.perKey())
...
                .apply("WriteMessages", PubsubIO.writeMessages().to("projects/preseem/topics/carlos-test"));

Notice that I write to pubsubio with 'writeMessages' (i.e. no attributes), yet code seems to die when trying to write out attributes.

Carlos.


Caused by: org.apache.beam.sdk.util.UserCodeException: java.lang.NullPointerException
org.apache.beam.sdk.util.UserCodeException.wrap(UserCodeException.java:36)
org.apache.beam.sdk.transforms.MapElements$1$auxiliary$u4qfc9DK.invokeProcessElement(Unknown Source)
org.apache.beam.runners.core.SimpleDoFnRunner.invokeProcessElement(SimpleDoFnRunner.java:197)
org.apache.beam.runners.core.SimpleDoFnRunner.processElement(SimpleDoFnRunner.java:158)
com.google.cloud.dataflow.worker.runners.worker.SimpleParDoFn.processElement(SimpleParDoFn.java:246)
com.google.cloud.dataflow.worker.runners.worker.ForwardingParDoFn.processElement(ForwardingParDoFn.java:42)
com.google.cloud.dataflow.worker.runners.worker.DataflowWorkerLoggingParDoFn.processElement(DataflowWorkerLoggingParDoFn.java:47)
com.google.cloud.dataflow.worker.util.common.worker.ParDoOperation.process(ParDoOperation.java:48)
com.google.cloud.dataflow.worker.util.common.worker.OutputReceiver.process(OutputReceiver.java:52)
com.google.cloud.dataflow.worker.runners.worker.SimpleParDoFn$1.output(SimpleParDoFn.java:194)
org.apache.beam.runners.core.SimpleDoFnRunner$DoFnContext.outputWindowedValue(SimpleDoFnRunner.java:355)
org.apache.beam.runners.core.SimpleDoFnRunner$DoFnProcessContext.output(SimpleDoFnRunner.java:629)
org.apache.beam.examples.GaugeKVToMessage.processElement(GaugeDebug.java:396)
org.apache.beam.examples.GaugeKVToMessage$auxiliary$xI4IkwZo.invokeProcessElement(Unknown Source)
org.apache.beam.runners.core.SimpleDoFnRunner.invokeProcessElement(SimpleDoFnRunner.java:197)
org.apache.beam.runners.core.SimpleDoFnRunner.processElement(SimpleDoFnRunner.java:158)
com.google.cloud.dataflow.worker.runners.worker.SimpleParDoFn.processElement(SimpleParDoFn.java:246)
com.google.cloud.dataflow.worker.runners.worker.ForwardingParDoFn.processElement(ForwardingParDoFn.java:42)
com.google.cloud.dataflow.worker.runners.worker.DataflowWorkerLoggingParDoFn.processElement(DataflowWorkerLoggingParDoFn.java:47)
com.google.cloud.dataflow.worker.util.common.worker.ParDoOperation.process(ParDoOperation.java:48)
com.google.cloud.dataflow.worker.util.common.worker.OutputReceiver.process(OutputReceiver.java:52)
com.google.cloud.dataflow.worker.runners.worker.GroupAlsoByWindowsParDoFn$1.output(GroupAlsoByWindowsParDoFn.java:149)
com.google.cloud.dataflow.worker.runners.worker.SimpleOldDoFnRunner$DoFnContext.outputWindowedValue(SimpleOldDoFnRunner.java:270)
com.google.cloud.dataflow.worker.runners.worker.SimpleOldDoFnRunner$DoFnContext.outputWindowedValue(SimpleOldDoFnRunner.java:266)
com.google.cloud.dataflow.worker.runners.worker.SimpleOldDoFnRunner$DoFnProcessContext$1.outputWindowedValue(SimpleOldDoFnRunner.java:463)
com.google.cloud.dataflow.worker.runners.worker.WindowingInternalsAdapters$2.outputWindowedValue(WindowingInternalsAdapters.java:63)
org.apache.beam.runners.core.ReduceFnRunner$2.output(ReduceFnRunner.java:1014)
org.apache.beam.runners.core.ReduceFnContextFactory$OnTriggerContextImpl.output(ReduceFnContextFactory.java:428)
org.apache.beam.runners.core.SystemReduceFn.onTrigger(SystemReduceFn.java:118)
org.apache.beam.runners.core.ReduceFnRunner.onTrigger(ReduceFnRunner.java:1019)
org.apache.beam.runners.core.ReduceFnRunner.emit(ReduceFnRunner.java:893)
org.apache.beam.runners.core.ReduceFnRunner.onTimers(ReduceFnRunner.java:758)
com.google.cloud.dataflow.worker.runners.worker.GroupAlsoByWindowViaWindowSetDoFn.processElement(GroupAlsoByWindowViaWindowSetDoFn.java:90)
com.google.cloud.dataflow.worker.runners.worker.SimpleOldDoFnRunner.invokeProcessElement(SimpleOldDoFnRunner.java:122)
com.google.cloud.dataflow.worker.runners.worker.SimpleOldDoFnRunner.processElement(SimpleOldDoFnRunner.java:101)
org.apache.beam.runners.core.LateDataDroppingDoFnRunner.processElement(LateDataDroppingDoFnRunner.java:73)
com.google.cloud.dataflow.worker.runners.worker.GroupAlsoByWindowsParDoFn.processElement(GroupAlsoByWindowsParDoFn.java:106)
com.google.cloud.dataflow.worker.runners.worker.ForwardingParDoFn.processElement(ForwardingParDoFn.java:42)
com.google.cloud.dataflow.worker.runners.worker.DataflowWorkerLoggingParDoFn.processElement(DataflowWorkerLoggingParDoFn.java:47)
com.google.cloud.dataflow.worker.util.common.worker.ParDoOperation.process(ParDoOperation.java:48)
com.google.cloud.dataflow.worker.util.common.worker.OutputReceiver.process(OutputReceiver.java:52)
com.google.cloud.dataflow.worker.util.common.worker.ReadOperation.runReadLoop(ReadOperation.java:198)
com.google.cloud.dataflow.worker.util.common.worker.ReadOperation.start(ReadOperation.java:159)
com.google.cloud.dataflow.worker.util.common.worker.MapTaskExecutor.execute(MapTaskExecutor.java:72)
com.google.cloud.dataflow.worker.runners.worker.StreamingDataflowWorker.process(StreamingDataflowWorker.java:791)
com.google.cloud.dataflow.worker.runners.worker.StreamingDataflowWorker.access$600(StreamingDataflowWorker.java:104)
com.google.cloud.dataflow.worker.runners.worker.StreamingDataflowWorker$9.run(StreamingDataflowWorker.java:873)
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
java.util.HashMap.putMapEntries(HashMap.java:500)
java.util.HashMap.putAll(HashMap.java:784)
com.google.cloud.dataflow.worker.repackaged.com.google.protobuf.MapField$MutatabilityAwareMap.putAll(MapField.java:343)
com.google.cloud.dataflow.worker.repackaged.com.google.pubsub.v1.PubsubMessage$Builder.putAllAttributes(PubsubMessage.java:880)
com.google.cloud.dataflow.worker.runners.worker.PubsubSink$PubsubWriter.add(PubsubSink.java:131)
com.google.cloud.dataflow.worker.runners.worker.PubsubSink$PubsubWriter.add(PubsubSink.java:111)
com.google.cloud.dataflow.worker.util.common.worker.WriteOperation.process(WriteOperation.java:82)
com.google.cloud.dataflow.worker.util.common.worker.OutputReceiver.process(OutputReceiver.java:52)
com.google.cloud.dataflow.worker.runners.worker.SimpleParDoFn$1.output(SimpleParDoFn.java:194)
org.apache.beam.runners.core.SimpleDoFnRunner$DoFnContext.outputWindowedValue(SimpleDoFnRunner.java:355)
org.apache.beam.runners.core.SimpleDoFnRunner$DoFnProcessContext.output(SimpleDoFnRunner.java:629)
org.apache.beam.sdk.transforms.MapElements$1.processElement(MapElements.java:122)
java.lang.RuntimeException: org.apache.beam.sdk.util.
Aug 04, 2017 1:50:32 PM org.apache.beam.runners.dataflow.DataflowPipelineJob$1 run

Activity

  1. cbazza commented on Aug 4, 2017

    @cbazza
    Author

    Ok, I found the problem and it is that google dataflow worker can not handle pubsubmessage with no attributes. The local runner handles it fine but when deployed to dataflow it crashes, so had to add attributes hashmap instead of just passing null:

             Map<String, String> attributes = new HashMap<String,String>();
             attributes.put("carlos", "carlos");
             PubsubMessage m = new PubsubMessage(data, attributes);
    

    Carlos.

  2. tekjar commented on Aug 25, 2017

    @tekjar

    Yep. I'm facing this too. Adding dummy attributes fixed this

  3. aaltay commented on Aug 25, 2017

    @aaltay
    Contributor
  4. asiFarran commented on Oct 11, 2019

    @asiFarran

    This has cost me about 10hrs and a fair bit of hair loss. Simply incredible.
    All hail @cbazza!

  5. cbazza commented on Oct 11, 2019

    @cbazza
    Author

    Thank you... I lost all my hair ;) You will come across other weirdness too when you try to debug large pipelines. I had enormous ones.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Metadata

Metadata

Assignees

No one assigned

    Labels

    No labels
    No labels

    Type

    No type

    Projects

    No projects

      Milestone

      No milestone

      Relationships

      None yet

      Development

      No branches or pull requests

      Issue actions