initial commit

zfs_smart_snapshot/__init__.py

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+

zfs_smart_snapshot/main.py

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+from datetime import datetime
+from dateutil.relativedelta import relativedelta
+
+
+def keep_date(now, snapshots, date_convert, delta, count):
+    keep = set()
+    if count < 1:
+        return keep
+    start_date = date_convert(now) - delta*(count-1)
+    for snapshot in snapshots:
+        if snapshot.date() >= start_date:
+            keep.add(snapshot)
+            start_date = date_convert(snapshot) + delta
+        if start_date > now.date():
+            break
+    return keep
+
+
+def keep_year(now, snapshots, count):
+    return keep_date(now, snapshots, lambda d: d.date().replace(day=1, month=1), relativedelta(years=1), count)
+
+
+def keep_month(now, snapshots, count):
+    return keep_date(now, snapshots, lambda d: d.date().replace(day=1), relativedelta(months=1), count)
+
+
+def keep_day(now, snapshots, count):
+    return keep_date(now, snapshots, lambda d: d.date(), relativedelta(days=1), count)
+
+
+def keep_time(now, snapshots, convert, delta, count):
+    keep = set()
+    if count < 1:
+        return keep
+    start = convert(now) - delta*(count-1)
+    for snapshot in snapshots:
+        if snapshot >= start:
+            keep.add(snapshot)
+            start = convert(snapshot) + delta
+        if start > now:
+            break
+    return keep
+
+
+def keep_hour(now, snapshots, count):
+    return keep_time(now, snapshots, lambda d: d.replace(minute=0, second=0, microsecond=0), relativedelta(hours=1),
+                     count)
+
+
+def keep_frequent(now, snapshots, count):
+    return keep_time(now, snapshots, lambda d: d.replace(minute=d.minute//15*15, second=0, microsecond=0),
+                     relativedelta(minutes=15), count)
+
+
+def snapshots_to_keep(now, snapshots, yearly=0, monthly=0, weekly=0, daily=0, hourly=0, frequently=0):
+    snapshots.sort()
+    keep = set()
+    keep.union(keep_year(now, snapshots, yearly))
+    keep.union(keep_month(now, snapshots, monthly))
+    keep.union(keep_day(now, snapshots, daily))
+    return keep
+
+
+def main():
+    print("Hello, world!")