1207ee2838
This commit addresses 8 high-priority issues identified in code analysis. Fixes #3, #4, #5, #7, #10, #19, #20, #21 ## Critical Bug Fixes 1. **Race condition in lock file creation (#3)** - Changed to atomic file creation using os.O_CREAT | os.O_EXCL - Prevents two processes from both acquiring the lock - Location: curateipsum/backup.py:110-115 2. **Invalid lock file error handling (#4)** - Added try/except for corrupted/empty lock files - Gracefully removes corrupted locks and retries - Location: curateipsum/backup.py:121-133 3. **SIGKILL vs SIGTERM issue (#5)** - Now sends SIGTERM first for graceful shutdown - Waits 5 seconds before escalating to SIGKILL - Allows previous process to clean up resources - Location: curateipsum/backup.py:146-156 4. **Wrong stat object for permissions (#7)** - Fixed bug where dst_stat was used instead of src_stat - Permissions are now correctly updated during rsync - Location: curateipsum/fs.py:371 5. **os.chown() fails for non-root users (#10)** - Wrapped all os.chown() calls in try/except blocks - Logs debug message instead of crashing - Allows backups to succeed for non-root users - Locations: curateipsum/fs.py:217-221, 228-231, 383-387, 469-472 ## Comprehensive Test Coverage 6. **Lock file tests (#19)** - Added TestBackupLock class with 7 test cases - Tests: creation, concurrent prevention, stale locks, corruption - Location: tests/test_backups.py:228-330 7. **Filesystem operation tests (#20)** - Added tests/test_fs_extended.py with 6 test classes - Tests: copy_file, copy_direntry, rsync, hardlink_dir, scantree, rm_direntry - 20+ test cases covering normal and edge cases - Location: tests/test_fs_extended.py 8. **Integration tests (#21)** - Added tests/test_integration.py with 2 test classes - Tests full backup workflow end-to-end - Tests: incremental backups, hardlinks, delta dirs, cleanup, recovery - 14 test cases covering complete backup lifecycle - Location: tests/test_integration.py ## Test Results All 68 tests pass successfully: - 11 original backup cleanup tests - 7 new lock file tests - 16 original fs tests - 20 new fs extended tests - 14 new integration tests ## Impact These fixes address critical bugs that could cause: - Data corruption from concurrent backups - Incomplete cleanup from forced process termination - Permission sync failures - Tool unusability for non-root users The comprehensive test coverage ensures these bugs are caught early and provides confidence for future refactoring.
cura-te-ipsum
cura-te-ipsum is a space-efficient incremental backup utility for Linux and macOS that uses hardlinks to minimize storage usage while maintaining complete directory snapshots.
Similar to Time Machine or rsnapshot, cura-te-ipsum creates backups that appear as complete directory trees but intelligently share unchanged files between snapshots, dramatically reducing storage requirements.
Features
- Space-Efficient Incremental Backups: Creates full directory snapshots using hardlinks, unchanged files share inodes with previous backups
- Intelligent Retention Policies: Automatic cleanup with configurable grandfather-father-son rotation (daily/weekly/monthly/yearly)
- Pure Python Implementation: No external dependencies required for basic operation (optional rsync support available)
- Delta Tracking: Automatically identifies and tracks changed files between backups
- Backup Integrity: Lock files and completion markers prevent concurrent runs and identify incomplete backups
- Safe Operations: Dry-run mode to preview changes before execution
- Cross-Platform: Supports both Linux and macOS
Installation
From Source
git clone https://github.com/snegov/cura-te-ipsum.git
cd cura-te-ipsum
pip install .
Requirements
- Python 3.6 or higher
- Linux or macOS operating system
- Optional:
rsyncand GNUcpfor alternative implementation modes
Usage
Basic Backup
cura-te-ipsum -b /path/to/backups /path/to/source
This creates a timestamped backup in /path/to/backups/YYYY-MM-DD_HH-MM-SS/.
Multiple Sources
cura-te-ipsum -b /backups /home/user/documents /home/user/photos
Command-Line Options
cura-te-ipsum -b BACKUPS_DIR SOURCE [SOURCE ...]
Required Arguments:
-b BACKUPS_DIR Directory where backups will be stored
SOURCE One or more directories to backup
Optional Arguments:
-n, --dry-run Preview changes without creating backup
-f, --force Force run even if previous backup is in progress
-v, --verbose Enable debug logging
--external-rsync Use external rsync instead of Python implementation
--external-hardlink Use cp/gcp command for hardlinking
Examples
Dry run to preview changes:
cura-te-ipsum -b /backups /home/user/data --dry-run
Verbose output for debugging:
cura-te-ipsum -b /backups /home/user/data --verbose
Using external rsync:
cura-te-ipsum -b /backups /home/user/data --external-rsync
How It Works
Hardlink-Based Snapshots
cura-te-ipsum creates complete directory snapshots, but files that haven't changed between backups share the same inode (hardlinked). This means:
- Each backup appears as a complete, browseable directory tree
- Only changed or new files consume additional disk space
- Deleting old backups doesn't affect other snapshots until the last reference is removed
Backup Process
- Lock Acquisition: Creates
.backups_lockto prevent concurrent operations - Hardlink Creation: Hardlinks all files from the most recent backup
- Rsync Sync: Syncs source directories to the new backup, updating changed files
- Delta Tracking: Copies changed/new files to
.backup_deltadirectory - Completion Marker: Creates
.backup_finishedmarker file - Cleanup: Removes old backups based on retention policy
- Lock Release: Removes lock file
Retention Policy
Default retention (configurable in code):
- 7 days: Keep all backups
- 30 days: Keep one backup per day
- 52 weeks: Keep one backup per week
- 12 months: Keep one backup per month
- 5+ years: Keep one backup per year
The cleanup process never deletes the only remaining backup.
Backup Structure
backups/
2025-01-15_10-30-00/ # backup snapshot
.backup_finished # completion marker
.backup_delta/ # changed files in this backup
[your backed up files] # complete directory tree
2025-01-16_10-30-00/
.backup_finished
.backup_delta/
[your backed up files]
.backups_lock # lock file (only during backup)
Development
Running Tests
pip install -r requirements-dev.txt
pytest
CI/CD
GitHub Actions automatically runs tests on Python 3.6 through 3.11 for every push and pull request.
Author
Maks Snegov (snegov@spqr.link)
Project Status
Development Status: Pre-Alpha
This project is actively maintained and used in production for personal backups, but the API and configuration options may change in future releases.