def _handle_sequential_dumps(previous_snaps, current_snapname, individuals, backlog_num=None):
"""Dump according to a sequential scheme.
Keep last backlog_num snaps, and dump with this algorithm:
step 1) FULL 0
step 2) INCR 0-1
step 3) INCR 1-2
..
If a backlog_num is specified, keep that many most-recent snapshots; if 0,
infinite; if not specified, remove all but last."""
global _opts
if backlog_num is None and _opts:
backlog_num = _opts.backlog_num
num_previous_snaps = len(previous_snaps)
if not individuals:
incremental_send(previous_snaps[-1], current_snapname, num_previous_snaps)
else:
for ds in individuals:
incremental_send(previous_snaps[-1], current_snapname, num_previous_snaps, dataset=ds)
# clean up old serie
if backlog_num == 0 or backlog_num > len(previous_snaps):
return
if backlog_num is None:
backlog_num = 1
for snap in previous_snaps[: len(previous_snaps) - backlog_num + 1]:
zfs.destroy_snapshot(snap)
def _handle_alternate_dumps(previous_snaps, current_snapname, individuals, backlog_num=None):
"""Dump according to an alternate scheme.
Keep last backlog_num snaps, and dump with this algorithm:
step 1) FULL 0
step 2) INCR 0-1
step 3) INCR 0-2
step 4) INCR 1-3
step 5) INCR 2-4
...
If a backlog_num is specified, keep that many most-recent snapshots; if 0,
infinite; if not specified, remove all but last."""
num_previous_snaps = len(previous_snaps)
if backlog_num and len(previous_snaps) >= backlog_num:
# time to start from scratch
print "Starting over after %d steps." % len(previous_snaps)
for ds in individuals:
bkfname = full_send(current_snapname, dataset=ds)
# prune old serie, if any
print "Cleaning up snapshots from old series."
for snap in previous_snaps:
zfs.destroy_snapshot(snap)
_done()
# go incremental from 2 steps ago
assert num_previous_snaps > 0
if num_previous_snaps == 1:
# backup from base snap
if not individuals:
incremental_send(previous_snaps[0], current_snapname, num_previous_snaps)
else:
for ds in individuals:
incremental_send(previous_snaps[0], current_snapname, num_previous_snaps, dataset=ds)
else:
# backup from 2 steps before
if not individuals:
incremental_send(previous_snaps[-2], current_snapname, num_previous_snaps)
else:
for ds in individuals:
incremental_send(previous_snaps[-2], current_snapname, num_previous_snaps, dataset=ds)
def main():
# get user options
global _opts
_opts, args = get_option_parser().parse_args()
# cleanup options
if _opts.exclude_datasets:
_opts.exclude_datasets = [ds.rstrip("/") for ds in _opts.exclude_datasets]
if _opts.only_datasets:
_opts.only_datasets = [ds.rstrip("/") for ds in _opts.only_datasets]
if _opts.individual_dump_ds:
_opts.individual_dump_ds = [ds.rstrip("/") for ds in _opts.individual_dump_ds]
# get context
snapctx = zsnapman.SnapshotContext(_opts.context)
if _opts.individual_dump_ds:
# pick the first as representative
operating_dataset = _opts.individual_dump_ds[0]
else:
# default to root
operating_dataset = ""
# some manual handling?
if _opts.list_snapshots:
if _opts.context == "*":
print "Contexts available:"
for c in zsnapman.existing_contexts():
print c
for ctx in zsnapman.existing_contexts():
_list_context(ctx, operating_dataset)
else:
_list_context(_opts.context, operating_dataset)
_done()
elif _opts.prune_exceeding_minutes is not None:
print "Pruning '%s' snapshots older than '%d' minutes" % (_opts.context, _opts.prune_exceeding_minutes)
for snap in snapctx.get_outdated_snapshots(
backlog_minutes=_opts.prune_exceeding_minutes, dataset=operating_dataset
):
zfs.destroy_snapshot(snap)
_done()
## done with manual handling
# kill outdated snapshots
for snap in snapctx.get_outdated_snapshots(
backlog_num=_opts.backlog_num, backlog_minutes=_opts.maxminutes, dataset=operating_dataset
):
zfs.destroy_snapshot(snap)
# get survived snaps in this context
previous_snaps = snapctx.get_snapshots(dataset=operating_dataset)
# take new snapshot
# what dataset take individually?
if _opts.only_datasets:
ids = _opts.only_datasets
elif _opts.individual_dump_ds:
# these
ids = _opts.individual_dump_ds
else:
# none specific, dump once root recursively
ids = None
# proceed taking the snapshot for the current session
if not _opts.nosnap:
current_snapname = snapctx.make_snap_name()
zfs.take_snapshot(current_snapname, restrictdatasets=ids, nodatasets=_opts.exclude_datasets)
else:
if not previous_snaps:
print "No existing snapshots in '%s'. Cannot proceed." % _opts.context
current_snapname = previous_snaps.pop()
if not _opts.send:
_done()
# dump is required
if (
_opts.fulldump
or len(previous_snaps) == 0
or (_opts.backlog_num is not None and len(previous_snaps) >= _opts.backlog_num)
):
# full dump
if not ids:
bkfname = full_send(current_snapname)
else:
for ds in ids:
bkfname = full_send(current_snapname, dataset=ds)
_done()
# look for what incremental algorithm the user wants
if _opts.alternate_dumps:
_handle_alternate_dumps(previous_snaps, current_snapname, individuals=ids)
else:
_handle_sequential_dumps(previous_snaps, current_snapname, individuals=ids)
_done()
