Fix Azure blob storage race condition with size-based upload #665
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Replace uploadStream() with upload() for documents <100MB. Fallback to uploadStream() for large files (>100MB). Problem: Multiple instances uploading same blob with uploadStream() causes race conditions when committing blocks, resulting in 'invalid block list' errors from Azure Storage. Solution: - Documents <100MB: Use upload() for atomic single-operation upload (no blocks, no commit phase, no race conditions possible) - Documents >=100MB: Use uploadStream() with original maxConcurrency=5 (still has multi-instance race risk, but handles memory better than buffering entire file) Note: maxConcurrency parameter only affects chunk parallelism within a single upload operation, not race conditions between multiple instances. For large files with critical data integrity, consider implementing Azure blob leases (pessimistic locking) as documented by Azure.
elrayle
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Dec 16, 2025
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elrayle
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Good addition to start hardening the reliability of uploads.
jeffmendoza
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Dec 16, 2025
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Part of #664
Replace uploadStream() with upload() for documents <100MB. Fallback to uploadStream() for large files (>100MB).
Problem:
Multiple instances uploading same blob with uploadStream() causes race conditions when committing blocks, resulting in 'invalid block list' errors from Azure Storage.
Solution:
Note: maxConcurrency parameter only affects chunk parallelism within a single upload operation, not race conditions between multiple instances. For large files with critical data integrity, consider implementing Azure blob leases (pessimistic locking) as documented by Azure.