def get_snapshots(self, root=DEFAULT_POOL):
snapshots = []
datasets = self.get_datasets()
for dataset in datasets:
# BTRFS in kernel has a weird bug where listing will fail
# immediately after a filesystem update. Loop on list until
# it is successful
try_again = True
failure = False
while try_again:
try:
subvol_reader = reader(StringIO(btrfs_cmd.subvolume.list("--sort=path", "-s", dataset)), delimiter=" ")
if failure:
log.debug("btrfs listing finished")
try_again = False
except ErrorReturnCode_19:
if not failure:
failure = True
log.debug("btrfs listing failed")
for row in subvol_reader:
if 'btrfs-auto-snap' in row[-1:][0] and row[-1:][0].startswith('.btrfs-auto-snap'):
_, interval, label = row[-1:][0].split("/")
snapshots.append(Snapshot(self, dataset, interval, label, size=1))
return snapshots
def auto_snapshot(self, interval, keep):
"""create auto-snapshot set with interval,
purging old snapshots"""
fs_config = self.get_config()
now = datetime.now()
date = "%s-%s-%s-%sh%s" % (str(now.year), str(now.month).zfill(2),
str(now.day).zfill(2),
str(now.hour).zfill(2),
str(now.minute).zfill(2))
key = "auto-snapshot:%s" % interval
to_snapshot = []
exclude = []
for dataset in sorted(fs_config.keys()):
if fs_config[dataset]['auto-snapshot']:
if key in fs_config[dataset].keys():
if fs_config[dataset][key]:
to_snapshot.append(dataset)
else:
exclude.append(dataset)
else:
to_snapshot.append(dataset)
else:
exclude.append(dataset)
log.debug("Snapshotting the following: %s" % ' '.join(to_snapshot))
log.debug("Excluding the following: %s" % ' '.join(exclude))
for dataset in to_snapshot:
self.commit_snapshot(dataset, interval, date)
def destroy_snapshot(self, name):
"""callout to zfs command to destroy snapshot"""
# name = "%s@%s" % (filesystem, interval)
if env.DRY_RUN:
log.info("dry-run: would destroy %s" % name)
else:
log.debug("destroy_snapshot(%s)" % (name))
if "@" in name:
zfs_cmd.destroy(name)
else:
log.error("should not be destroying a dataset! name: %s" % name)
def destroy_snapshot(self, name):
"""callout to btrfs command to destroy snapshot"""
if env.DRY_RUN:
log.info("dry-run: would destroy %s" % name)
else:
log.debug("destroy_snapshot(%s)" % (name))
if os.access(name, os.F_OK):
if "/.btrfs-auto-snap/" in name:
btrfs_cmd.subvolume.delete(name)
else:
log.error("should not be destroying a dataset! name: %s" % name)
else:
log.error("cannot find %s" % name)
def commit_snapshot(self, filesystem, interval, label):
"""call out to zfs command to create snapshot
return a Snapshot object"""
name = "%s@zfs-auto-snap_%s-%s" % (filesystem, interval, label)
current_snapshots = [s.name for s in self.get_snapshots()]
if name in current_snapshots:
log.error("snapshot %s already exists, not overwriting!" % name)
return
if env.DRY_RUN:
log.info("dry-run: would commit %s" % name)
else:
log.debug("commit_snapshot(%s, %s, %s)" % (filesystem, interval, label))
zfs_cmd.snapshot(name)
def is_enabled(cls):
if os.geteuid() != 0:
log.debug("btrfs is only enabled for the root user!")
return False
if not sys.platform.startswith('linux'):
log.debug("btrfs is only enabled on linux!")
return False
elif BTRFS_AVAILABLE:
if "v0.19" in btrfs_cmd("--version"):
log.warning("'btrfs' command v0.19 is incompatible, please upgrade to at least v0.20 to enable btrfs")
return False
return True
else:
return False
def commit_snapshot(self, dataset, interval, label):
"""call out to btrfs command to create snapshot
return a Snapshot object"""
snap_dir = os.path.join(dataset, '.btrfs-auto-snap')
interval_dir = os.path.join(snap_dir, interval)
destination = os.path.join(interval_dir, label)
if os.path.exists(destination):
log.error("snapshot %s already exists, not overwriting!" % destination)
return
# if interval_dir isn't a directory, and also isn't a file with that name
# create the snapshot label directory
if not os.path.isdir(interval_dir) and not os.path.exists(interval_dir):
s = os.stat(snap_dir)
os.mkdir(interval_dir)
os.chown(interval_dir, s[stat.ST_UID], s[stat.ST_GID])
if env.DRY_RUN:
log.info("dry-run: would commit %s" % (destination))
else:
log.debug("commit_snapshot(%s, %s, %s)" % (dataset, interval, label))
btrfs_cmd.subvolume.snapshot(dataset, destination)
import stat
from csv import reader
from StringIO import StringIO
from tardis import log, env, Snapshot
from tardis.fs import Filesystem
import re
try:
from sh import btrfs as btrfs_cmd
BTRFS_AVAILABLE = True
except:
BTRFS_AVAILABLE = False
log.debug("unable to find btrfs command")
from sh import ErrorReturnCode_19
def dir_is_writable(directory):
s = os.stat(directory)
mode = s[stat.ST_MODE]
return bool(
(mode & stat.S_IWUSR) or
(mode & stat.S_IWGRP) or
(mode & stat.S_IWOTH)
)
class Btrfs(Filesystem):
