Implement Issue #245 Snapshot exclude patterns

zfs_autobackup/ZfsAuto.py

@@ -1,4 +1,5 @@
 import argparse
+import re
 import sys
 
 from .CliBase import CliBase
@@ -112,6 +113,14 @@ class ZfsAuto(CliBase):
                             help=argparse.SUPPRESS)
 
 
+        def regex_argument_type(input_line):
+            """Parses regex arguments into re.Pattern objects"""
+            try:
+                return re.compile(input_line)
+            except:
+                raise ValueError("Could not parse argument '{}' as a regular expression".format(input_line))
+        group.add_argument('--exclude-snapshot-pattern', action='append', default=[], type=regex_argument_type, help="Regular expression to match snapshots that will be ignored.")
+
         return parser
 
     def print_error_sources(self):

zfs_autobackup/ZfsAutobackup.py

@@ -472,7 +472,8 @@ class ZfsAutobackup(ZfsAuto):
                                   snapshot_time_format=self.snapshot_time_format, hold_name=self.hold_name, logger=self,
                                   ssh_config=self.args.ssh_config,
                                   ssh_to=self.args.ssh_source, readonly=self.args.test,
-                                  debug_output=self.args.debug_output, description=description, thinner=source_thinner)
+                                  debug_output=self.args.debug_output, description=description, thinner=source_thinner,
+                                  exclude_snapshot_patterns=self.args.exclude_snapshot_pattern)
 
             ################# select source datasets
             self.set_title("Selecting")

zfs_autobackup/ZfsAutoverify.py

@@ -235,7 +235,8 @@ class ZfsAutoverify(ZfsAuto):
                                   snapshot_time_format=self.snapshot_time_format, hold_name=self.hold_name, logger=self,
                                   ssh_config=self.args.ssh_config,
                                   ssh_to=self.args.ssh_source, readonly=self.args.test,
-                                  debug_output=self.args.debug_output, description=description)
+                                  debug_output=self.args.debug_output, description=description,
+                                  exclude_snapshot_patterns=self.args.exclude_snapshot_pattern)
 
             ################# select source datasets
             self.set_title("Selecting")

zfs_autobackup/ZfsDataset.py

@@ -124,6 +124,20 @@ class ZfsDataset:
     def is_snapshot(self):
         """true if this dataset is a snapshot"""
         return self.name.find("@") != -1
+    
+    @property
+    def is_excluded(self):
+        """true if this dataset is a snapshot and matches the exclude pattern"""
+        if not self.is_snapshot:
+            return False
+        
+
+        for pattern in self.zfs_node.exclude_snapshot_patterns:
+            if pattern.search(self.name) is not None:
+                self.debug("Excluded (path matches snapshot exclude pattern)")
+                return True
+        
+        
 
     def is_selected(self, value, source, inherited, exclude_received, exclude_paths, exclude_unchanged):
         """determine if dataset should be selected for backup (called from
@@ -1171,7 +1185,7 @@ class ZfsDataset:
             target_snapshot = target_dataset.find_snapshot(source_snapshot)  # still virtual
 
             # does target actually want it?
-            if target_snapshot not in target_obsoletes:
+            if target_snapshot not in target_obsoletes and not source_snapshot.is_excluded:
 
                 # do the rollback, one time at first transfer
                 if do_rollback:

zfs_autobackup/ZfsNode.py

@@ -20,7 +20,7 @@ class ZfsNode(ExecuteNode):
 
     def __init__(self, logger, utc=False, snapshot_time_format="", hold_name="", ssh_config=None, ssh_to=None, readonly=False,
                  description="",
-                 debug_output=False, thinner=None):
+                 debug_output=False, thinner=None, exclude_snapshot_patterns=[]):
 
         self.utc = utc
         self.snapshot_time_format = snapshot_time_format
@@ -30,6 +30,8 @@ class ZfsNode(ExecuteNode):
 
         self.logger = logger
 
+        self.exclude_snapshot_patterns = exclude_snapshot_patterns
+
         if ssh_config:
             self.verbose("Using custom SSH config: {}".format(ssh_config))