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ParquetMetadataConverter should never log at level WARN

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#3,025 0 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Stale
Tech stack
java
Domain
data-engineering

Research direction

Start by reading parquet-hadoop/src/main/java/org/apache/parquet/format/converter/ParquetMetadataConverter.java at the referenced line and inspect the surrounding metadata conversion behavior. Check relevant converter tests and logging conventions, then confirm with maintainers whether the warning should be removed, downgraded, or replaced with an exception. Done means the agreed behavior is implemented without unintended compatibility changes and covered by an appropriate regression test.

Written by the indexing model from the issue text.

Description

Type: bug
Describe the bug, including details regarding any error messages, version, and platform.

When ParquetMetadataConverter encounters a mismatch between logical and converted type, it logs a message at level WARN. https://github.com/apache/parquet-java/blob/eed26b4ea96881cc543b4233cdddece5d1d608d7/parquet-hadoop/src/main/java/org/apache/parquet/format/converter/ParquetMetadataConverter.java#L1864

This behavior does not make sense because one of two things must be true:

  1. This is an issue that can affect normal operation and the application needs to (potentially) respond to it
  2. This is not a concern for the calling application and it won't impact normal operation

If item 1 is true, then an exception should be thrown and the application choose to respond or not (possibly by logging). If item item 2 is true, then the log message should either be omitted entirely or be logged at level DEBUG (INFO level would still be too spammy)

I would be happy to submit a patch if there is consensus about which approach to take. Perhaps there should be a flag to control whether the exception should be thrown to avoid breaking existing code.

Component(s)

No response

Dominant language
Java
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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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