zfssnap: use property for pruning

1 files changed, 15 insertions, 7 deletions

diff --git a/modules/zfssnap/zfssnap.py b/modules/zfssnap/zfssnap.py
index b72174fc..e77f11f3 100644
--- a/modules/zfssnap/zfssnap.py
+++ b/modules/zfssnap/zfssnap.py
@@ -32,7 +32,7 @@ def _now():
 
 def _snap_name(item, time=_now()):
     suffix = re.sub(r'\+00:00$', r'Z', time.isoformat(timespec='seconds'))
-    return f'{item}@auto_{suffix}'
+    return f'{item}@{suffix}'
 
 def _log_cmd(*args):
     fmt_args = ' '.join(map(shlex.quote, args))
@@ -53,8 +53,18 @@ def _get_items():
     return items
         
 def prune(config, dry_run, keep_newest):
-    items = defaultdict(list)
+    prunable_snapshots = set()
+    args = ['zfs', 'get', '-H', '-p', '-o', 'name,value', '-t', 'snapshot', '-s', 'local' 'li.yggdrasil:is-auto-snapshot']
+    _log_cmd(*args)
+    with subprocess.Popen(args, stdout=subprocess.PIPE) as proc:
+        text_stdout = io.TextIOWrapper(proc.stdout)
+        reader = csv.reader(text_stdout, delimiter='\t', quoting=csv.QUOTE_NONE)
+        Row = namedtuple('Row', ['name', 'is_auto_snapshot'])
+        for row in map(Row._make, reader):
+            if bool(strtobool(row.is_auto_snapshot)):
+                prunable_snapshots.add(row.name)
 
+    items = defaultdict(list)
     Snap = namedtuple('Snap', ['name', 'creation'])
     args = ['zfs', 'get', '-H', '-p', '-o', 'name,value', '-t', 'snapshot', 'creation']
     _log_cmd(*args)
@@ -63,12 +73,10 @@ def prune(config, dry_run, keep_newest):
         reader = csv.reader(text_stdout, delimiter='\t', quoting=csv.QUOTE_NONE)
         Row = namedtuple('Row', ['name', 'timestamp'])
         for row in map(Row._make, reader):
-            creation = datetime.fromtimestamp(int(row.timestamp), timezone.utc)
-            base_name, _, _ = row.name.rpartition('@')
-            expected_name = _snap_name(base_name, time=creation)
-            if expected_name != row.name:
-                # logger.debug(f'Skipping ‘{row.name}’ since it does not conform to naming scheme')
+            if row.name is not in prunable_snapshots:
                 continue
+
+            creation = datetime.fromtimestamp(int(row.timestamp), timezone.utc)
             items[base_name].append(Snap(name=row.name, creation=creation))
 
     kept_count = defaultdict(lambda: defaultdict(lambda: 0))