Files
cura-te-ipsum/curateipsum/cli.py
T
a48eaf8117 Make snapshot creation transactional (#5)
* Make snapshot creation transactional

Build each snapshot in a private .incomplete-<name> staging directory
instead of mutating the final backup path directly. Any failure while
building the snapshot (hardlink failure, rsync error, or a single
Actions.ERROR entry) is now fatal: the staging directory is discarded
and BackupFailedError is raised, so a failed or interrupted backup can
never silently look like a success.

On success, the completion marker is written and the directory fsync'd
before an atomic os.rename() into the final snapshot name, so a crash
can never leave a partially-populated directory under a real snapshot
name.

Also:
- cleanup_stale_staging_dirs() removes abandoned staging directories
  left by a crashed run before a new backup starts.
- _reserve_snapshot_name() avoids same-second snapshot name collisions.
- cli.py releases the backup lock in finally and returns a nonzero
  exit code when BackupFailedError is raised.

Updates the error-recovery tests that previously asserted failures
were swallowed silently to assert BackupFailedError is raised instead,
matching the new fail-loud contract.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

* Address Copilot review feedback on transactional snapshots

- Remove unused uuid import.
- _reserve_snapshot_name() also checks for a collision with an existing
  .incomplete-<name> staging directory, not just the final snapshot
  name.
- _fsync_dir() opens with O_DIRECTORY where available.
- Fsync the completion marker file itself, and fsync the parent
  backups_dir after the rename, so the marker and the rename survive a
  crash/power loss.
- Re-raise an already-BackupFailedError unchanged (preserving its
  traceback) instead of wrapping it in a new instance; only
  fs.BackupCreationError gets wrapped.
- Wrap the initial os.mkdir(staging.path) failure in BackupFailedError
  so every failure path uses the documented exception.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

---------

Co-authored-by: Maxim Shulga <maxim.shulga@alludo.com>
Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
2026-08-03 21:30:39 +00:00

125 lines
4.2 KiB
Python
Executable File

#!/usr/bin/env python
import argparse
import logging
import os.path
import shutil
import sys
import time
from datetime import timedelta
from curateipsum import backup
from curateipsum._version import version
_lg = logging.getLogger("curateipsum")
SUPPORTED_PLATFORMS = ("linux", "darwin")
def main():
formatter = logging.Formatter("{asctime}|{levelname}|{message}", style="{")
console_handler = logging.StreamHandler()
console_handler.setFormatter(formatter)
parser = argparse.ArgumentParser(
prog="cura-te-ipsum",
description="cura-te-ipsum, my personal backup software.",
)
parser.add_argument("-V", "--version",
action="version",
version=f"%(prog)s v{version}")
parser.add_argument("-v", "--verbose",
action="store_true",
default=False,
help="print verbose information")
parser.add_argument("-b",
dest="backups_dir",
metavar="BACKUPS_DIR",
type=str,
required=True,
help="directory, where all backups will be stored")
parser.add_argument("-n", "--dry-run",
action="store_true",
default=False,
help="Do not do create backup")
parser.add_argument("-f", "--force",
action="store_true",
default=False,
help="Force run when previous backup is still in process")
parser.add_argument("--external-rsync",
action="store_true",
default=False,
help="Use external rsync for copying")
parser.add_argument("--external-hardlink",
action="store_true",
default=False,
help="Use cp command for creating hardlink copies")
parser.add_argument("sources",
nargs="+",
metavar="SOURCE",
type=str,
help="backup source (file/dir/smth else)")
args = parser.parse_args()
loglevel = logging.DEBUG if args.verbose else logging.INFO
logging.basicConfig(level=loglevel, handlers=[console_handler])
_lg.info("Starting %s: %s", parser.prog, args)
if sys.platform not in SUPPORTED_PLATFORMS:
_lg.error("Not supported platform: %s. Supported platforms: %s",
sys.platform, SUPPORTED_PLATFORMS)
return 1
if args.external_rsync and not shutil.which("rsync"):
_lg.error("rsync should be installed to use --external-rsync option.")
return 1
cp_program = "gcp" if sys.platform == "darwin" else "cp"
if args.external_hardlink and not shutil.which(cp_program):
_lg.error("%s should be installed to use --external-hardlink option.",
cp_program)
return 1
backups_dir_abs = os.path.abspath(args.backups_dir)
if not os.path.isdir(backups_dir_abs):
_lg.error("Backup directory %s does not exist, exiting",
args.backups_dir)
return 1
for src_dir in args.sources:
if not os.path.isdir(src_dir):
_lg.error("Source directory %s does not exist", src_dir)
return 1
start_time = time.time()
if not backup.set_backups_lock(backups_dir_abs, args.force):
return 1
exit_code = 0
try:
backup.cleanup_old_backups(backups_dir=backups_dir_abs,
dry_run=args.dry_run)
backup.initiate_backup(
sources=args.sources,
backups_dir=backups_dir_abs,
dry_run=args.dry_run,
external_rsync=args.external_rsync,
external_hardlink=args.external_hardlink,
)
except backup.BackupFailedError as err:
_lg.error("Backup failed: %s", err)
exit_code = 1
finally:
backup.release_backups_lock(backups_dir_abs)
end_time = time.time()
spent_time = end_time - start_time
_lg.info("Finished, time spent: %s", str(timedelta(seconds=spent_time)))
return exit_code
if __name__ == "__main__":
sys.exit(main())