The persistent EOFException shows Parquet expects 78 more bytes than exist.
This suggests a mismatch between what was written vs what's in chunks.
Added logging to track:
1. Buffer state at close (position before flush)
2. Stream position when flushing metadata
3. Chunk count vs file size in attributes
4. Explicit fileSize setting from stream position
Key hypothesis:
- Parquet writes N bytes total (e.g., 762)
- Stream.position tracks all writes
- But only (N-78) bytes end up in chunks
- This causes Parquet read to fail with 'Still have: 78 bytes left'
If buffer.position() = 78 at close, the buffer wasn't flushed.
If position != chunk total, write submission failed.
If attr.fileSize != position, metadata is inconsistent.
Next run will show which scenario is happening.
chrislu