Evgeny created BEAM-6086: ---------------------------- Summary: Flaky tests when using PCollectionView with View.asSingleton() Key: BEAM-6086 URL: https://issues.apache.org/jira/browse/BEAM-6086 Project: Beam Issue Type: Bug Components: beam-model Reporter: Evgeny Assignee: Kenneth Knowles
Here is the minimal project that demonstrates the issue https://github.com/medvedev1088/dataflow-flaky-tests. About 1 time out of 10 the tests will fail with org.apache.beam.sdk.Pipeline$PipelineExecutionException: java.lang.IllegalArgumentException: Empty PCollection accessed as a singleton view. Consider setting withDefault to provide a default value at org.apache.beam.runners.direct.DirectRunner$DirectPipelineResult.waitUntilFinish(DirectRunner.java:332) at org.apache.beam.runners.direct.DirectRunner$DirectPipelineResult.waitUntilFinish(DirectRunner.java:302) at org.apache.beam.runners.direct.DirectRunner.run(DirectRunner.java:197) at org.apache.beam.runners.direct.DirectRunner.run(DirectRunner.java:64) at org.apache.beam.sdk.Pipeline.run(Pipeline.java:313) at org.apache.beam.sdk.testing.TestPipeline.run(TestPipeline.java:350) at org.apache.beam.sdk.testing.TestPipeline.run(TestPipeline.java:331) at com.beam.MyPipelineTest.testTokenTransfersBasic(MyPipelineTest.java:29) 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.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47) at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17) at org.apache.beam.sdk.testing.TestPipeline$1.evaluate(TestPipeline.java:319) at org.junit.rules.RunRules.evaluate(RunRules.java:20) at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) at org.junit.runners.ParentRunner.run(ParentRunner.java:363) at org.junit.runner.JUnitCore.run(JUnitCore.java:137) at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68) at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47) at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242) at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70) Caused by: java.lang.IllegalArgumentException: Empty PCollection accessed as a singleton view. Consider setting withDefault to provide a default value at org.apache.beam.sdk.transforms.View$SingletonCombineFn.identity(View.java:378) at org.apache.beam.sdk.transforms.Combine$BinaryCombineFn.extractOutput(Combine.java:436) at org.apache.beam.sdk.transforms.Combine$BinaryCombineFn.extractOutput(Combine.java:384) at org.apache.beam.sdk.transforms.Combine$CombineFn.apply(Combine.java:353) at org.apache.beam.sdk.transforms.Combine$GroupedValues$1.processElement(Combine.java:2056) Related to https://jira.apache.org/jira/browse/BEAM-6036 -- This message was sent by Atlassian JIRA (v7.6.3#76005)