Re: Parquet data stream group converter error

[Jesse Lord]

I should have mentioned that I was able to read the same file in the batch 
ParquetTableSource. It is only when reading it in a stream that I encounter 
this error.

- Jesse
________________________________
From: Khachatryan Roman <khachatryan.ro...@gmail.com>
Sent: Friday, July 3, 2020 12:08:51 AM
To: Jesse Lord <jl...@vectra.ai>
Cc: user@flink.apache.org <user@flink.apache.org>
Subject: Re: Parquet data stream group converter error

Hi,

> MessageType schema = reader.getFooter().getFileMetaData().getSchema();
The first thing I'd suggest is to verify that the file contains a valid schema 
and can be read by some other program, e.g. parquet-tools schema or cat [1].

Regards,
Roman


On Thu, Jul 2, 2020 at 11:36 PM Jesse Lord 
<jl...@vectra.ai<mailto:jl...@vectra.ai>> wrote:

I am trying to read a parquet file into a datastream and then register that 
stream as a temporary table. This file is created by spark 2.4 in HDFS on AWS 
EMR. I am using flink version 1.10.0 with EMR 5.30.



I am getting the following error:



Caused by: org.apache.flink.streaming.runtime.tasks.AsynchronousException: 
Caught exception when processing split: null

        at 
org.apache.flink.streaming.runtime.tasks.StreamTask$StreamTaskAsyncExceptionHandler.handleAsyncException(StreamTask.java:1090)

        at 
org.apache.flink.streaming.runtime.tasks.StreamTask.handleAsyncException(StreamTask.java:1058)

        at 
org.apache.flink.streaming.api.functions.source.ContinuousFileReaderOperator$SplitReader.run(ContinuousFileReaderOperator.java:351)

Caused by: java.lang.ClassCastException: Expected instance of group converter 
but got 
"org.apache.flink.formats.parquet.utils.RowConverter$RowPrimitiveConverter"

        at 
org.apache.parquet.io.api.Converter.asGroupConverter(Converter.java:34)

        at 
org.apache.parquet.io.RecordReaderImplementation.<init>(RecordReaderImplementation.java:267)

        at 
org.apache.parquet.io.MessageColumnIO$1.visit(MessageColumnIO.java:147)

        at 
org.apache.parquet.io.MessageColumnIO$1.visit(MessageColumnIO.java:109)

        at 
org.apache.parquet.filter2.compat.FilterCompat$NoOpFilter.accept(FilterCompat.java:165)

        at 
org.apache.parquet.io.MessageColumnIO.getRecordReader(MessageColumnIO.java:109)

        at 
org.apache.flink.formats.parquet.utils.ParquetRecordReader.createRecordReader(ParquetRecordReader.java:118)

        at 
org.apache.flink.formats.parquet.utils.ParquetRecordReader.readNextRecord(ParquetRecordReader.java:227)

        at 
org.apache.flink.formats.parquet.utils.ParquetRecordReader.reachEnd(ParquetRecordReader.java:207)

        at 
org.apache.flink.formats.parquet.ParquetInputFormat.reachedEnd(ParquetInputFormat.java:233)

        at 
org.apache.flink.streaming.api.functions.source.ContinuousFileReaderOperator$SplitReader.run(ContinuousFileReaderOperator.java:327)



Below is a snippet of code that shows how I am trying to read the parquet file:



    String filePath = "hdfs:///path/to/single/file.parquet";



    ParquetFileReader reader = 
ParquetFileReader.open(HadoopInputFile.fromPath(new 
org.apache.hadoop.fs.Path(filePath), new Configuration()));

    MessageType schema = reader.getFooter().getFileMetaData().getSchema();



    String parquetPath = "hdfs:///path/to/parquet/directory”;



    DataStream<Row> parquetStream = env.readFile(new ParquetRowInputFormat(new 
org.apache.flink.core.fs.Path(parquetPath), schema), parquetPath);



    Table parquetTable = tEnv.fromDataStream(parquetStream);

    tEnv.createTemporaryView("isession", parquetTable);



Thanks,

Jesse