[
https://issues.apache.org/jira/browse/SPARK-1630?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14077492#comment-14077492
]
Josh Rosen commented on SPARK-1630:
-----------------------------------
In the current Spark codebase, the PythonRDD constructor is only called from
Python code. In order for a user-created Scala/Java RDD<String> to be passed
to PySpark, the user would need to have dug deep into PySpark's private APIs to
call out to Java/Scala code to create a transformed RDD and wrap it into a
PythonRDD. Given this, is it fair to say that any in-the-wild NPEs encountered
here by using Spark's public APIs are due to bugs in Spark/PySpark, or is there
a case that I'm overlooking (e.g. is TextInputFormat allowed to return nulls?)?
> PythonRDDs don't handle nulls gracefully
> ----------------------------------------
>
> Key: SPARK-1630
> URL: https://issues.apache.org/jira/browse/SPARK-1630
> Project: Spark
> Issue Type: Bug
> Components: PySpark, SQL
> Affects Versions: 0.9.0, 0.9.1
> Reporter: Kalpit Shah
> Assignee: Davies Liu
> Original Estimate: 2h
> Remaining Estimate: 2h
>
> If PythonRDDs receive a null element in iterators, they currently NPE. It
> would be better do log a DEBUG message and skip the write of NULL elements.
> Here are the 2 stack traces :
> 14/04/22 03:44:19 ERROR executor.Executor: Uncaught exception in thread
> Thread[stdin writer for python,5,main]
> java.lang.NullPointerException
> at
> org.apache.spark.api.python.PythonRDD$.writeIteratorToStream(PythonRDD.scala:267)
> at org.apache.spark.api.python.PythonRDD$$anon$2.run(PythonRDD.scala:88)
> -------------------------------------------------------------------------------------
> Py4JJavaError: An error occurred while calling
> z:org.apache.spark.api.python.PythonRDD.writeToFile.
> : java.lang.NullPointerException
> at org.apache.spark.api.python.PythonRDD$.writeUTF(PythonRDD.scala:273)
> at
> org.apache.spark.api.python.PythonRDD$$anonfun$writeIteratorToStream$2.apply(PythonRDD.scala:247)
> at
> org.apache.spark.api.python.PythonRDD$$anonfun$writeIteratorToStream$2.apply(PythonRDD.scala:246)
> at scala.collection.Iterator$class.foreach(Iterator.scala:727)
> at scala.collection.AbstractIterator.foreach(Iterator.scala:1157)
> at
> org.apache.spark.api.python.PythonRDD$.writeIteratorToStream(PythonRDD.scala:246)
> at org.apache.spark.api.python.PythonRDD$.writeToFile(PythonRDD.scala:285)
> at org.apache.spark.api.python.PythonRDD$.writeToFile(PythonRDD.scala:280)
> at org.apache.spark.api.python.PythonRDD.writeToFile(PythonRDD.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 py4j.reflection.MethodInvoker.invoke(MethodInvoker.java:231)
> at py4j.reflection.ReflectionEngine.invoke(ReflectionEngine.java:379)
> at py4j.Gateway.invoke(Gateway.java:259)
> at py4j.commands.AbstractCommand.invokeMethod(AbstractCommand.java:132)
> at py4j.commands.CallCommand.execute(CallCommand.java:79)
> at py4j.GatewayConnection.run(GatewayConnection.java:207)
> at java.lang.Thread.run(Thread.java:744)
--
This message was sent by Atlassian JIRA
(v6.2#6252)
