feat: [document-compression-updater]- Improvements: Auto-remove dummy compression field, drop tracker collection and more

[NestorRV]

Summary

• Add connection retry logic and startup validation
• Fix UnboundLocalError on empty collection in setup()
• Replace bare print() calls with printLog() throughout
• Add per-batch ASCII progress bar, elapsed time, rate, and ETA logging
• Auto-remove dummy compression field after each batch via $unset
• Add --skip-cleanup and --append-log flags
• Drop tracker collection on successful completion
• Remove dead multiprocessing queue code and unused imports

Changes

Error Handling

• Added get_mongo_client() helper with retry logic (up to 3 attempts, 5s delay) used everywhere a connection is needed
• Added validate_connection() called at startup to verify the URI is reachable and the target database/collection exist before any work begins
• Fixed an UnboundLocalError crash in setup() when the collection is empty
• Wrapped all MongoDB operations in setup() and task_worker() with try/except, with reconnect logic in the worker's batch loop

Code Quality

• Removed unused imports: threading, string
• Removed redundant variable assignments at the top of task_worker()
• Added --append-log flag — log file is no longer silently deleted on every startup unless the flag is omitted

Observability

• Replaced all bare print() calls with printLog() for consistent output to both stdout and the log file
• Added per-batch ASCII progress bar, elapsed time, docs/sec rate, and ETA after each batch

Correctness

• The dummy field used to trigger compression is now automatically removed from each document immediately after each batch via a second bulk_write with $unset
• Added --skip-cleanup flag for cases where removing the field is not required
• Each tracker entry now includes a cleanupComplete boolean
• On successful completion the tracker collection is automatically dropped

README

• Updated to reflect all new flags: --append-log, --skip-cleanup
• Added notes on automatic dummy field cleanup and tracker collection drop behaviour

🤖 Generated with Claude Code