fix checking of existing snapshots for spacefilled fs names...

bin/zsnapper

@@ -5,6 +5,7 @@ import os
 import re
 import logging
 import logging.handlers
+import stat
 import subprocess
 import sys
 
@@ -258,7 +259,7 @@ def weed_snapshots(fslist, snapshots, config, failed_snapshots):
             continue
         if source_fs not in snapshots:
             continue
-        if not conf['weed_enable']:
+        if not conf['weed_enable'] or conf['weed_enable'].lower() in ('false', 'no'):
             continue
 
         kwargs = {k: int(v) for k, v in conf.items() if k in [
@@ -288,7 +289,8 @@ def weed_snapshots(fslist, snapshots, config, failed_snapshots):
 
 def main():
     config = configparser.ConfigParser()
-    config.read('/etc/zsnapper.ini')
+    config.read(['/usr/local/etc/zsnapper.ini', '/etc/zsnapper.ini'])
+
     ret = RET_CODES['SUCCESS']
     log = logging.getLogger(LOGGER)
 
@@ -367,9 +369,9 @@ def main():
         try:
             if remote in remote_snapshots:
                 remote_snapshots[remote] = zsnaplib.get_snapshots(zfs_cmd)
-        except zsnaplib.ZFSSnapshotError:
+        except zsnaplib.ZFSSnapshotError as e:
             del remote_snapshots[remote]
-            log.warning("Could not refresh snapshots on {}".format(remote))
+            log.warning("Could not refresh snapshots on {}: {}".format(remote, e))
     snapshots = zsnaplib.get_snapshots(local_zfs_cmd)
 
     failed_send = send_snapshots(fslist, snapshots, config)
@@ -403,9 +405,22 @@ if __name__ == '__main__':
     handler.setLevel(logging.WARNING)
     log.addHandler(handler)
 
-    handler = logging.handlers.SysLogHandler(address='/dev/log')
+    handler = None
+    for logsocket in ('/var/run/log', '/dev/log'):
+        try:
+            mode = os.stat(logsocket).st_mode
+        except FileNotFoundError:
+            continue
+
+        if stat.S_ISSOCK(mode):
+            handler = logging.handlers.SysLogHandler(address=logsocket)
             formatter = logging.Formatter(fmt='zsnapper[%(process)s] %(message)s')
             handler.setFormatter(formatter)
             handler.setLevel(logging.INFO)
             log.addHandler(handler)
+            break
+
+    if not handler:
+        log.warning('No syslog socket found, will not log to syslog')
+
     sys.exit(main())

setup.py

@@ -6,7 +6,7 @@ try:
 except ImportError:
     from distutils import setup
 
-version = '0.3'
+version = '0.3.4'
 
 setup(
         name='zsnapper',

zsnaplib/__init__.py

@@ -6,6 +6,7 @@ import sys
 
 time_format='%Y-%m-%d_%H%M'
 re_snapshot = re.compile(r'^(.*)@([0-9]{4}-[0-9]{2}-[0-9]{2}_[0-9]{4})$')
+re_err_ok = re.compile(r"cannot create snapshot '[^']+': dataset already exists")
 logger = 'zsnapper'
 
 class ZFSSnapshotError(Exception):
@@ -33,7 +34,12 @@ def do_zfs_command(args, zfs_cmd, pipecmd=None):
 
     (out, err) = ctrl_proc.communicate()
 
-    if ctrl_proc.returncode != 0:
+    # check if we try to create a snapshot that already exists. This can happen
+    # if the script is run every minute and it takes more time than that to
+    # create all snapshots
+    if ctrl_proc.returncode == 1 and re.match(re_err_ok, err.decode('utf-8')):
+        pass
+    elif ctrl_proc.returncode != 0:
         raise ZFSSnapshotError('Failed to execute {}: {}'.format(cmd, err))
     return out
 
@@ -77,7 +83,7 @@ def get_filesystems(zfs_cmd):
 
     for row in out.splitlines():
         row = row.decode('UTF-8')
-        ret.add(row.split()[0])
+        ret.add(row.split('\t')[0])
     return ret
 
 
@@ -87,7 +93,7 @@ def get_snapshots(zfs_cmd):
     snapshots = {}
 
     for row in out.splitlines():
-        row = row.decode('UTF-8').split()[0]
+        row = row.decode('UTF-8').split('\t')[0]
         res = re_snapshot.match(row)
         if res:
             d = datetime.datetime.strptime(res.group(2), time_format)