zfs snap trimmer for freenas

1 files changed, 114 insertions, 0 deletions

diff --git a/freenas/snap_trimmer.py b/freenas/snap_trimmer.py
new file mode 100644
index 0000000..93641e9
--- /dev/null
+++ b/freenas/snap_trimmer.py
@@ -0,0 +1,114 @@
+#!/usr/bin/env python3
+
+""" 
+Used to trim ZFS snapshots on a FreeNAS appliance if they're being sent from another appliance
+and rather than 1:1 replication you want a different retention policy on the backups.
+There is nothing elegant about this, and in fact it's fairly inefficient.  It was a quick
+solution to a problem I had.  PRs accepted. 
+"""
+
+import requests
+import argparse
+
+api_user = 'root'
+api_pass = 'YourPassword'
+
+def delete_snap(id):
+    r = requests.delete("https://localhost/api/v1.0/storage/snapshot/{}".format(id), auth=(api_user, api_pass), verify=False)
+    if r.status_code != 204:
+        print("Could not delete snap: {}. HTTP response {}".format(id, r.status_code))
+    return
+
+parser = argparse.ArgumentParser()
+parser.add_argument("--filesystem", help="The name of the filesystem to trim snaps for", required=True, type=str)
+parser.add_argument("--keephourly", help="The number of hourly snaps to keep", required=True, type=int)
+parser.add_argument("--keepdaily", help="The number of daily snaps to keep", required=True, type=int)
+parser.add_argument("--keepweekly", help="The number of weekly snaps to keep", required=True, type=int)
+parser.add_argument("--keepmonthly", help="The number of monthly snaps to keep", required=True, type=int)
+args = parser.parse_args()
+
+filesystem = args.filesystem
+keep_hourly = args.keephourly
+keep_daily = args.keepdaily
+keep_weekly = args.keepweekly 
+keep_monthly = args.keepmonthly
+
+query_params = {"limit": 0}
+r = requests.get("https://localhost/api/v1.0/storage/snapshot/", verify=False, auth=(api_user, api_pass), params=query_params)
+
+all_snaps = r.json()
+
+my_snaps = []
+for snap in all_snaps:
+    if filesystem == snap['filesystem']:
+        my_snaps.append(snap['fullname'])
+
+hourly_snaps = []
+daily_snaps = []
+weekly_snaps = []
+monthly_snaps = []
+for snap in my_snaps:
+    if snap[-1:] == 'h':
+        hourly_snaps.append(snap)
+    elif snap[-1:] == 'd':
+        daily_snaps.append(snap)
+    elif snap[-1:] == 'w':
+        weekly_snaps.append(snap)
+    elif snap[-1:] == 'm':
+        monthly_snaps.append(snap)
+    else:
+        print("No idea what's going on here")
+
+# Sort all of our lists, useful later for trimming snaps to the proper numbers
+hourly_snaps.sort()
+daily_snaps.sort()
+weekly_snaps.sort()
+monthly_snaps.sort()
+
+if len(hourly_snaps) > keep_hourly:
+    to_delete = len(hourly_snaps) - keep_hourly
+    snap_names = []
+    counter = 0 
+    while counter < to_delete:
+        snap_names.append(hourly_snaps.pop(0))
+        counter = counter + 1 
+    for snap in snap_names:
+        for result in all_snaps:
+            if result['fullname'] == snap:
+                delete_snap(result['id'])
+
+if len(daily_snaps) > keep_daily:
+    to_delete = len(daily_snaps) - keep_daily
+    snap_names = []
+    counter = 0 
+    while counter < to_delete:
+        snap_names.append(daily_snaps.pop(0))
+        counter = counter + 1 
+    for snap in snap_names:
+        for result in all_snaps:
+            if result['fullname'] == snap:
+                delete_snap(result['id'])
+
+if len(weekly_snaps) > keep_weekly:
+    to_delete = len(weekly_snaps) - keep_weekly
+    snap_names = []
+    counter = 0 
+    while counter < to_delete:
+        snap_names.append(weekly_snaps.pop(0))
+        counter = counter + 1 
+    for snap in snap_names:
+        for result in all_snaps:
+            if result['fullname'] == snap:
+                delete_snap(result['id'])
+
+if len(monthly_snaps) > keep_monthly:
+    to_delete = len(monthly_snaps) - keep_monthly
+    snap_names = []
+    counter = 0 
+    while counter < to_delete:
+        snap_names.append(monthly_snaps.pop(0))
+        counter = counter + 1 
+    for snap in snap_names:
+        for result in all_snaps:
+            if result['fullname'] == snap:
+                delete_snap(result['id'])