def delete_snapshot(self, snapshot: Subvolume) -> None:
logger = self._logger
filesystem_path = snapshot.filesystem_path
logical_path = snapshot.logical_path
try:
filesystem_path_str = str(filesystem_path)
is_subvolume = filesystem_path.exists() and btrfsutil.is_subvolume(
filesystem_path_str)
if is_subvolume:
root_dir_str = str(constants.ROOT_DIR)
num_id = snapshot.num_id
deleted_subvolumes = checked_cast(
list[int], btrfsutil.deleted_subvolumes(root_dir_str))
if num_id not in deleted_subvolumes:
logger.info(f"Deleting the '{logical_path}' snapshot.")
btrfsutil.delete_subvolume(filesystem_path_str)
else:
logger.warning(
f"The '{logical_path}' snapshot has already "
"been deleted but not yet cleaned up.")
else:
logger.warning(
f"The '{filesystem_path}' directory is not a subvolume.")
except btrfsutil.BtrfsUtilError as e:
logger.exception("btrfsutil call failed!")
raise SubvolumeError(
f"Could not delete the '{logical_path}' snapshot!") from e
def test_create_snapshot(self):
subvol = os.path.join(self.mountpoint, 'subvol')
btrfsutil.create_subvolume(subvol)
os.mkdir(os.path.join(subvol, 'dir'))
for i, arg in enumerate(self.path_or_fd(subvol)):
with self.subTest(type=type(arg)):
snapshots_dir = os.path.join(self.mountpoint, 'snapshots{}'.format(i))
os.mkdir(snapshots_dir)
snapshot = os.path.join(snapshots_dir, 'snapshot')
btrfsutil.create_snapshot(subvol, snapshot + '1')
self.assertTrue(btrfsutil.is_subvolume(snapshot + '1'))
self.assertTrue(os.path.exists(os.path.join(snapshot + '1', 'dir')))
btrfsutil.create_snapshot(subvol, (snapshot + '2').encode())
self.assertTrue(btrfsutil.is_subvolume(snapshot + '2'))
self.assertTrue(os.path.exists(os.path.join(snapshot + '2', 'dir')))
if HAVE_PATH_LIKE:
btrfsutil.create_snapshot(subvol, PurePath(snapshot + '3'))
self.assertTrue(btrfsutil.is_subvolume(snapshot + '3'))
self.assertTrue(os.path.exists(os.path.join(snapshot + '3', 'dir')))
nested_subvol = os.path.join(subvol, 'nested')
more_nested_subvol = os.path.join(nested_subvol, 'more_nested')
btrfsutil.create_subvolume(nested_subvol)
btrfsutil.create_subvolume(more_nested_subvol)
os.mkdir(os.path.join(more_nested_subvol, 'nested_dir'))
snapshot = os.path.join(self.mountpoint, 'snapshot')
btrfsutil.create_snapshot(subvol, snapshot + '1')
# Dummy subvolume.
self.assertEqual(os.stat(os.path.join(snapshot + '1', 'nested')).st_ino, 2)
self.assertFalse(os.path.exists(os.path.join(snapshot + '1', 'nested', 'more_nested')))
btrfsutil.create_snapshot(subvol, snapshot + '2', recursive=True)
self.assertTrue(os.path.exists(os.path.join(snapshot + '2', 'nested/more_nested/nested_dir')))
transid = btrfsutil.create_snapshot(subvol, snapshot + '3', recursive=True, no_wait=True)
self.assertTrue(os.path.exists(os.path.join(snapshot + '3', 'nested/more_nested/nested_dir')))
self.assertGreater(transid, 0)
btrfsutil.create_snapshot(subvol, snapshot + '4', read_only=True)
self.assertTrue(btrfsutil.get_subvolume_read_only(snapshot + '4'))
def test_create_snapshot(self):
subvol = os.path.join(self.mountpoint, 'subvol')
btrfsutil.create_subvolume(subvol)
os.mkdir(os.path.join(subvol, 'dir'))
for i, arg in enumerate(self.path_or_fd(subvol)):
with self.subTest(type=type(arg)):
snapshots_dir = os.path.join(self.mountpoint, 'snapshots{}'.format(i))
os.mkdir(snapshots_dir)
snapshot = os.path.join(snapshots_dir, 'snapshot')
btrfsutil.create_snapshot(subvol, snapshot + '1')
self.assertTrue(btrfsutil.is_subvolume(snapshot + '1'))
self.assertTrue(os.path.exists(os.path.join(snapshot + '1', 'dir')))
btrfsutil.create_snapshot(subvol, (snapshot + '2').encode())
self.assertTrue(btrfsutil.is_subvolume(snapshot + '2'))
self.assertTrue(os.path.exists(os.path.join(snapshot + '2', 'dir')))
if HAVE_PATH_LIKE:
btrfsutil.create_snapshot(subvol, PurePath(snapshot + '3'))
self.assertTrue(btrfsutil.is_subvolume(snapshot + '3'))
self.assertTrue(os.path.exists(os.path.join(snapshot + '3', 'dir')))
nested_subvol = os.path.join(subvol, 'nested')
more_nested_subvol = os.path.join(nested_subvol, 'more_nested')
btrfsutil.create_subvolume(nested_subvol)
btrfsutil.create_subvolume(more_nested_subvol)
os.mkdir(os.path.join(more_nested_subvol, 'nested_dir'))
snapshot = os.path.join(self.mountpoint, 'snapshot')
btrfsutil.create_snapshot(subvol, snapshot + '1')
# Dummy subvolume.
self.assertEqual(os.stat(os.path.join(snapshot + '1', 'nested')).st_ino, 2)
self.assertFalse(os.path.exists(os.path.join(snapshot + '1', 'nested', 'more_nested')))
btrfsutil.create_snapshot(subvol, snapshot + '2', recursive=True)
self.assertTrue(os.path.exists(os.path.join(snapshot + '2', 'nested/more_nested/nested_dir')))
transid = btrfsutil.create_snapshot(subvol, snapshot + '3', recursive=True, async_=True)
self.assertTrue(os.path.exists(os.path.join(snapshot + '3', 'nested/more_nested/nested_dir')))
self.assertGreater(transid, 0)
btrfsutil.create_snapshot(subvol, snapshot + '4', read_only=True)
self.assertTrue(btrfsutil.get_subvolume_read_only(snapshot + '4'))
def test_is_subvolume(self):
dir = os.path.join(self.mountpoint, 'foo')
os.mkdir(dir)
for arg in self.path_or_fd(self.mountpoint):
with self.subTest(type=type(arg)):
self.assertTrue(btrfsutil.is_subvolume(arg))
for arg in self.path_or_fd(dir):
with self.subTest(type=type(arg)):
self.assertFalse(btrfsutil.is_subvolume(arg))
with self.assertRaises(btrfsutil.BtrfsUtilError) as e:
btrfsutil.is_subvolume(os.path.join(self.mountpoint, 'bar'))
# This is a bit of an implementation detail, but really this is testing
# that the exception is initialized correctly.
self.assertEqual(e.exception.btrfsutilerror, btrfsutil.ERROR_STATFS_FAILED)
self.assertEqual(e.exception.errno, errno.ENOENT)
def test_is_subvolume(self):
dir = os.path.join(self.mountpoint, 'foo')
os.mkdir(dir)
for arg in self.path_or_fd(self.mountpoint):
with self.subTest(type=type(arg)):
self.assertTrue(btrfsutil.is_subvolume(arg))
for arg in self.path_or_fd(dir):
with self.subTest(type=type(arg)):
self.assertFalse(btrfsutil.is_subvolume(arg))
with self.assertRaises(btrfsutil.BtrfsUtilError) as e:
btrfsutil.is_subvolume(os.path.join(self.mountpoint, 'bar'))
# This is a bit of an implementation detail, but really this is testing
# that the exception is initialized correctly.
self.assertEqual(e.exception.btrfsutilerror, btrfsutil.ERROR_STATFS_FAILED)
self.assertEqual(e.exception.errno, errno.ENOENT)
def _create_writable_snapshot_from(self, source: Subvolume) -> Subvolume:
logger = self._logger
snapshot_manipulation = self.package_config.snapshot_manipulation
destination_directory = snapshot_manipulation.destination_directory
if not destination_directory.exists():
directory_permissions = constants.SNAPSHOTS_ROOT_DIR_PERMISSIONS
octal_permissions = "{0:o}".format(directory_permissions)
try:
logger.info(
f"Creating the '{destination_directory}' destination "
f"directory with {octal_permissions} permissions.")
destination_directory.mkdir(mode=directory_permissions,
parents=True)
except OSError as e:
logger.exception("Path.mkdir() call failed!")
raise SubvolumeError(
f"Could not create the '{destination_directory}' destination directory!"
) from e
destination = source.to_destination(destination_directory)
source_logical_path = source.logical_path
snapshot_directory = destination.filesystem_path
try:
logger.info(
"Creating a new writable snapshot from the read-only "
f"'{source_logical_path}' snapshot at '{snapshot_directory}'.")
snapshot_directory_str = str(snapshot_directory)
is_subvolume = snapshot_directory.exists(
) and btrfsutil.is_subvolume(snapshot_directory_str)
if not is_subvolume:
source_filesystem_path_str = str(source.filesystem_path)
btrfsutil.create_snapshot(source_filesystem_path_str,
snapshot_directory_str,
read_only=False)
else:
logger.warning(
f"The '{snapshot_directory}' directory is already a subvolume."
)
except btrfsutil.BtrfsUtilError as e:
logger.exception("btrfsutil call failed!")
raise SubvolumeError(
f"Could not create a new writable snapshot at '{snapshot_directory}'!"
) from e
writable_snapshot = self.get_subvolume_from(snapshot_directory)
return none_throws(writable_snapshot).as_newly_created_from(source)
def test_create_subvolume(self):
subvol = os.path.join(self.mountpoint, 'subvol')
btrfsutil.create_subvolume(subvol + '1')
self.assertTrue(btrfsutil.is_subvolume(subvol + '1'))
btrfsutil.create_subvolume((subvol + '2').encode())
self.assertTrue(btrfsutil.is_subvolume(subvol + '2'))
if HAVE_PATH_LIKE:
btrfsutil.create_subvolume(PurePath(subvol + '3'))
self.assertTrue(btrfsutil.is_subvolume(subvol + '3'))
pwd = os.getcwd()
try:
os.chdir(self.mountpoint)
btrfsutil.create_subvolume('subvol4')
self.assertTrue(btrfsutil.is_subvolume('subvol4'))
finally:
os.chdir(pwd)
btrfsutil.create_subvolume(subvol + '5/')
self.assertTrue(btrfsutil.is_subvolume(subvol + '5'))
btrfsutil.create_subvolume(subvol + '6//')
self.assertTrue(btrfsutil.is_subvolume(subvol + '6'))
transid = btrfsutil.create_subvolume(subvol + '7', no_wait=True)
self.assertTrue(btrfsutil.is_subvolume(subvol + '7'))
self.assertGreater(transid, 0)
# Test creating subvolumes under '/' in a chroot.
pid = os.fork()
if pid == 0:
try:
os.chroot(self.mountpoint)
os.chdir('/')
btrfsutil.create_subvolume('/subvol8')
self.assertTrue(btrfsutil.is_subvolume('/subvol8'))
with self.assertRaises(btrfsutil.BtrfsUtilError):
btrfsutil.create_subvolume('/')
os._exit(0)
except Exception:
traceback.print_exc()
os._exit(1)
wstatus = os.waitpid(pid, 0)[1]
self.assertTrue(os.WIFEXITED(wstatus))
self.assertEqual(os.WEXITSTATUS(wstatus), 0)
def test_create_subvolume(self):
subvol = os.path.join(self.mountpoint, 'subvol')
btrfsutil.create_subvolume(subvol + '1')
self.assertTrue(btrfsutil.is_subvolume(subvol + '1'))
btrfsutil.create_subvolume((subvol + '2').encode())
self.assertTrue(btrfsutil.is_subvolume(subvol + '2'))
if HAVE_PATH_LIKE:
btrfsutil.create_subvolume(PurePath(subvol + '3'))
self.assertTrue(btrfsutil.is_subvolume(subvol + '3'))
pwd = os.getcwd()
try:
os.chdir(self.mountpoint)
btrfsutil.create_subvolume('subvol4')
self.assertTrue(btrfsutil.is_subvolume('subvol4'))
finally:
os.chdir(pwd)
btrfsutil.create_subvolume(subvol + '5/')
self.assertTrue(btrfsutil.is_subvolume(subvol + '5'))
btrfsutil.create_subvolume(subvol + '6//')
self.assertTrue(btrfsutil.is_subvolume(subvol + '6'))
transid = btrfsutil.create_subvolume(subvol + '7', async=True)
self.assertTrue(btrfsutil.is_subvolume(subvol + '7'))
self.assertGreater(transid, 0)
# Test creating subvolumes under '/' in a chroot.
pid = os.fork()
if pid == 0:
try:
os.chroot(self.mountpoint)
os.chdir('/')
btrfsutil.create_subvolume('/subvol8')
self.assertTrue(btrfsutil.is_subvolume('/subvol8'))
with self.assertRaises(btrfsutil.BtrfsUtilError):
btrfsutil.create_subvolume('/')
os._exit(0)
except Exception:
traceback.print_exc()
os._exit(1)
wstatus = os.waitpid(pid, 0)[1]
self.assertTrue(os.WIFEXITED(wstatus))
self.assertEqual(os.WEXITSTATUS(wstatus), 0)
def scan_dir(p: Path, filter_func=None):
"""Scans Path p for btrfs snapshots, returns the paths of all found snapshots as a list or None if no snapshots were found.
Snapshots can be filtered by passing a function as filter_func that takes a path and returns a boolean expression.
If such a function is present, only those snapshots where the filter function returns true will be returned in the snapshot list."""
snapshots = list()
for f in p.iterdir():
if btrfsutil.is_subvolume(f):
if filter_func is not None:
if filter_func(f):
snapshots.append(f)
else:
snapshots.append(f)
if len(snapshots) < 1:
return None
return snapshots
def get_subvolume_from(self, filesystem_path: Path) -> Optional[Subvolume]:
logger = self._logger
if not filesystem_path.exists():
raise SubvolumeError(
f"The '{filesystem_path}' path does not exist!")
if not filesystem_path.is_dir():
raise SubvolumeError(
f"The '{filesystem_path}' path does not represent a directory!"
)
try:
filesystem_path_str = str(filesystem_path)
if btrfsutil.is_subvolume(filesystem_path_str):
subvolume_id = btrfsutil.subvolume_id(filesystem_path_str)
subvolume_path = btrfsutil.subvolume_path(
filesystem_path_str, subvolume_id)
subvolume_read_only = btrfsutil.get_subvolume_read_only(
filesystem_path_str)
subvolume_info = btrfsutil.subvolume_info(
filesystem_path_str, subvolume_id)
self_uuid = default_if_none(
try_convert_bytes_to_uuid(subvolume_info.uuid),
constants.EMPTY_UUID,
)
parent_uuid = default_if_none(
try_convert_bytes_to_uuid(subvolume_info.parent_uuid),
constants.EMPTY_UUID,
)
return Subvolume(
filesystem_path,
subvolume_path,
datetime.fromtimestamp(subvolume_info.otime),
UuidRelation(self_uuid, parent_uuid),
NumIdRelation(subvolume_info.id, subvolume_info.parent_id),
subvolume_read_only,
)
except btrfsutil.BtrfsUtilError as e:
logger.exception("btrfsutil call failed!")
raise SubvolumeError(
f"Could not initialize the subvolume for '{filesystem_path}'!"
) from e
return None
