Adding some documentation, and the ability to specify the maximum number of snapshots per volume to keep

Author: pas256

README.rst

@@ -1,5 +1,98 @@
 Backup Monkey
 =============
 
-A monkey that makes sure you have snapshots of all your EBS volumes
+A monkey that makes sure you have a backup of your EBS volumes in case something goes wrong. 
 
+It is designed specifically for Amazon Web Services (AWS), and using Python and Boto.
+
+This script is designed to be run on a schedule, probably by CRON. 
+
+Usage
+-----
+
+::
+
+    usage: backup-monkey [-h] [--region REGION]
+                         [--max-snapshots-per-volume SNAPSHOTS] [--snapshot-only]
+                         [--remove-only] [--verbose] [--version]
+
+    Loops through all EBS volumes, and snapshots them, then loops through all
+    snapshots, and removes the oldest ones.
+
+    optional arguments:
+      -h, --help            show this help message and exit
+      --region REGION       the region to loop through and snapshot (default is
+                            current region of EC2 instance this is running on).
+                            E.g. us-east-1
+      --max-snapshots-per-volume SNAPSHOTS
+                            the maximum number of snapshots to keep per EBS
+                            volume. The oldest snapshots will be deleted. 
+                            Default: 3
+      --snapshot-only       Only snapshot EBS volumes, do not remove old snapshots
+      --remove-only         Only remove old snapshots, do not create new snapshots
+      --verbose, -v         enable verbose output (-vvv for more)
+      --version             display version number and exit
+      
+      
+
+Examples
+--------
+
+Create snapshots of all EBS volumes in us-east-1:
+
+::
+
+    backup-monkey --region us-east-1
+
+Delete snapshots of EBS volumes in us-west-1 where a volume has more than 5 snapshots:
+
+::
+
+    backup-monkey --region us-west-1 --max-snapshots-per-volume 5 --remove-only
+
+
+Installation
+------------
+
+You can install Backup Monkey using the usual PyPI channels. Example:
+
+::
+
+    sudo pip install backup_monkey
+    
+You can find the package details here: https://pypi.python.org/pypi/backup_monkey
+
+
+Warning
+-------
+
+Make no mistake. This script WILL delete snapshots. This script WILL create
+snapshots, which can cost you money. There really are no warranties or
+guarantees. For costs, refer to http://aws.amazon.com/ec2/pricing/
+
+
+About Answers for AWS
+---------------------
+
+This code was written by `Peter
+Sankauskas <https://twitter.com/pas256>`__, founder of `Answers for
+AWS <http://answersforaws.com/>`__ - a company focused on helping business learn
+how to use AWS, without doing it the hard way. If you are looking for help
+with AWS, please `contact us <http://answersforaws.com/contact/>`__.
+
+
+License
+-------
+
+Copyright 2013 Answers for AWS LLC
+
+Licensed under the Apache License, Version 2.0 (the "License"); you may
+not use this file except in compliance with the License. You may obtain
+a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable
+law or agreed to in writing, software distributed under the License is
+distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied. See the License for the specific
+language governing permissions and limitations under the License.
+      

lib/backup_monkey/__init__.py

@@ -13,4 +13,4 @@
 # limitations under the License.
 
 __author__ = 'Peter Sankauskas'
-__version__ = '0.5.0'
+__version__ = '0.9.0'

lib/backup_monkey/cli.py

@@ -36,6 +36,8 @@ def run():
     parser = argparse.ArgumentParser(description='Loops through all EBS volumes, and snapshots them, then loops through all snapshots, and removes the oldest ones.')
     parser.add_argument('--region', metavar='REGION', 
                         help='the region to loop through and snapshot (default is current region of EC2 instance this is running on). E.g. us-east-1')
+    parser.add_argument('--max-snapshots-per-volume', metavar='SNAPSHOTS', default=3, type=int,
+                        help='the maximum number of snapshots to keep per EBS volume. The oldest snapshots will be deleted. Default: 3')
     parser.add_argument('--snapshot-only', action='store_true', default=False,
                         help='Only snapshot EBS volumes, do not remove old snapshots')
     parser.add_argument('--remove-only', action='store_true', default=False,
@@ -65,7 +67,7 @@ def run():
         log.debug("Running in region: %s", region)
 
     try:
-        monkey = BackupMonkey(region)
+        monkey = BackupMonkey(region, args.max_snapshots_per_volume)
 
         if not args.remove_only:
             monkey.snapshot_volumes()

lib/backup_monkey/core.py

@@ -24,10 +24,10 @@
 
 
 class BackupMonkey(object):
-    def __init__(self, region):
+    def __init__(self, region, max_snapshots_per_volume):
         self._region = region
         self._prefix = 'BACKUP_MONKEY'
-        self._snapshots_per_volume = 3
+        self._snapshots_per_volume = max_snapshots_per_volume
 
         log.info("Connecting to region %s", self._region)
         self._conn = ec2.connect_to_region(self._region)