cleanedup and improved select-code

zfs_autobackup/ZfsDataset.py

@@ -90,6 +90,35 @@ def is_snapshot(self):
  """true if this dataset is a snapshot"""
  return self.name.find("@") != -1
 
+ def is_selected(self, value, source, inherited, ignore_received):
+ """determine if dataset should be selected for backup (called from ZfsNode)"""
+
+ # sanity checks
+ if source not in ["local", "received", "-"]:
+ # probably a program error in zfs-autobackup or new feature in zfs
+ raise (Exception(
+ "{} autobackup-property has illegal source: '{}' (possible BUG)".format(self.name, source)))
+ if value not in ["false", "true", "child", "-"]:
+ # user error
+ raise (Exception(
+ "{} autobackup-property has illegal value: '{}'".format(self.name, value)))
+
+ # now determine if its actually selected
+ if value == "false":
+ self.verbose("Ignored (disabled)")
+ return False
+ elif value == "true" or (value == "child" and inherited):
+ if source == "local":
+ self.verbose("Selected")
+ return True
+ elif source == "received":
+ if ignore_received:
+ self.verbose("Ignored (local backup)")
+ return False
+ else:
+ self.verbose("Selected")
+ return True
+
  @CachedProperty
  def parent(self):
  """get zfs-parent of this dataset. for snapshots this means it will get the filesystem/volume that it belongs

zfs_autobackup/ZfsNode.py

@@ -194,7 +194,7 @@ def consistent_snapshot(self, datasets, snapshot_name, min_changed_bytes):
  self.run(cmd, readonly=False)
 
  @CachedProperty
- def selected_datasets(self):
+ def selected_datasets(self, ignore_received=True):
  """determine filesystems that should be backupped by looking at the special autobackup-property, systemwide
 
  returns: list of ZfsDataset
@@ -204,35 +204,32 @@ def selected_datasets(self):
 
  # get all source filesystems that have the backup property
  lines = self.run(tab_split=True, readonly=True, cmd=[
- "zfs", "get", "-t", "volume,filesystem", "-o", "name,value,source", "-s", "local,inherited", "-H",
+ "zfs", "get", "-t", "volume,filesystem", "-o", "name,value,source", "-H",
  "autobackup:" + self.backup_name
  ])
 
- # determine filesystems that should be actually backupped
+ # The returnlist of selected ZfsDataset's:
  selected_filesystems = []
- direct_filesystems = []
+
+ # list of sources, used to resolve inherited sources
+ sources = {}
+
  for line in lines:
- (name, value, source) = line
+ (name, value, raw_source) = line
  dataset = ZfsDataset(self, name)
 
- if value == "false":
- dataset.verbose("Ignored (disabled)")
-
+ # "resolve" inherited sources
+ sources[name] = raw_source
+ if raw_source.find("inherited from ") == 0:
+ inherited = True
+ inherited_from = re.sub("^inherited from ", "", raw_source)
+ source = sources[inherited_from]
  else:
- if source == "local" and (value == "true" or value == "child"):
- direct_filesystems.append(name)
-
- if source == "local" and value == "true":
- dataset.verbose("Selected (direct selection)")
- selected_filesystems.append(dataset)
- elif source.find("inherited from ") == 0 and (value == "true" or value == "child"):
- inherited_from = re.sub("^inherited from ", "", source)
- if inherited_from in direct_filesystems:
- selected_filesystems.append(dataset)
- dataset.verbose("Selected (inherited selection)")
- else:
- dataset.debug("Ignored (already a backup)")
- else:
- dataset.verbose("Ignored (only childs)")
+ inherited = False
+ source = raw_source
+
+ # determine it
+ if dataset.is_selected(value=value, source=source, inherited=inherited, ignore_received=ignore_received):
+ selected_filesystems.append(dataset)
 
- return selected_filesystems
+ return selected_filesystems