releasing v3.0 final

usefull -> useful

.gitignore

@@ -0,0 +1,11 @@
+.vscode/settings.json
+token
+tokentest
+dist/
+build/
+zfs_autobackup.egg-info
+.eggs/
+__pycache__
+.coverage
+*.pyc
+python2.env

.travis.yml

@@ -0,0 +1,31 @@
+
+jobs:
+  include:
+    - os: linux
+      dist: xenial
+      language: python
+      python: 2.7
+    - os: linux
+      dist: xenial
+      language: python
+      python: 3.6
+    - os: linux
+      dist: bionic
+      language: python
+      python: 2.7
+    - os: linux
+      dist: bionic
+      language: python
+      python: 3.6
+
+
+
+
+before_install:
+  - sudo apt-get update
+  - sudo apt-get install zfsutils-linux
+
+script:
+  # - sudo -E ./ngrok.sh
+  - sudo -E ./run_tests
+  # - sudo -E pip --version

LICENSE

@@ -1,281 +1,622 @@
                     GNU GENERAL PUBLIC LICENSE
-                       Version 2, June 1991
+                       Version 3, 29 June 2007
 
- Copyright (C) 1989, 1991 Free Software Foundation, Inc., <http://fsf.org/>
- 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
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@@ -287,15 +628,15 @@ free software which everyone can redistribute and change under these terms.
 
   To do so, attach the following notices to the program.  It is safest
 to attach them to the start of each source file to most effectively
-convey the exclusion of warranty; and each file should have at least
+state the exclusion of warranty; and each file should have at least
 the "copyright" line and a pointer to where the full notice is found.
 
-    {description}
-    Copyright (C) {year}  {fullname}
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
 
-    This program is free software; you can redistribute it and/or modify
+    This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
-    the Free Software Foundation; either version 2 of the License, or
+    the Free Software Foundation, either version 3 of the License, or
     (at your option) any later version.
 
     This program is distributed in the hope that it will be useful,
@@ -303,38 +644,31 @@ the "copyright" line and a pointer to where the full notice is found.
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
 
-    You should have received a copy of the GNU General Public License along
-    with this program; if not, write to the Free Software Foundation, Inc.,
-    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+    You should have received a copy of the GNU General Public License
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 Also add information on how to contact you by electronic and paper mail.
 
-If the program is interactive, make it output a short notice like this
-when it starts in an interactive mode:
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
 
-    Gnomovision version 69, Copyright (C) year name of author
-    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    <program>  Copyright (C) <year>  <name of author>
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     This is free software, and you are welcome to redistribute it
     under certain conditions; type `show c' for details.
 
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-  `Gnomovision' (which makes passes at compilers) written by James Hacker.
-
-  {signature of Ty Coon}, 1 April 1989
-  Ty Coon, President of Vice
-
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+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
 
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+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

README.md

@@ -1,198 +1,420 @@
 # ZFS autobackup
 
-Introduction
-============
+[![Coverage Status](https://coveralls.io/repos/github/psy0rz/zfs_autobackup/badge.svg)](https://coveralls.io/github/psy0rz/zfs_autobackup) [![Build Status](https://travis-ci.org/psy0rz/zfs_autobackup.svg?branch=master)](https://travis-ci.org/psy0rz/zfs_autobackup)
 
-ZFS autobackup is used to periodicly backup ZFS filesystems to other locations. This is done using the very effcient zfs send and receive commands.
+## New in v3
 
-It has the following features:
-* Automaticly selects filesystems to backup by looking at a simple ZFS property. (recursive)
+* Complete rewrite, cleaner object oriented code.
+* Python 3 and 2 support.
+* Automated regression against real ZFS environment.
+* Installable via [pip](https://pypi.org/project/zfs-autobackup/).
+* Backwards compatible with your current backups and parameters.
+* Progressive thinning (via a destroy schedule. default schedule should be fine for most people)
+* Cleaner output, with optional color support (pip install colorama).
+* Clear distinction between local and remote output.
+* Summary at the beginning, displaying what will happen and the current thinning-schedule.
+* More efficient destroying/skipping snapshots on the fly. (no more space issues if your backup is way behind)
+* Progress indicator (--progress)
+* Better property management (--set-properties and --filter-properties)
+* Better resume handling, automatically abort invalid resumes.
+* More robust error handling.
+* Prepared for future enhancements.
+* Supports raw backups for encryption.
+* Custom SSH client config.
+
+
+## Introduction
+
+This is a tool I wrote to make replicating ZFS datasets easy and reliable. 
+
+You can either use it as a **backup** tool, **replication** tool or **snapshot** tool.
+
+You can select what to backup by setting a custom `ZFS property`. This allows you to set and forget: Configure it so it backups your entire pool, and you never have to worry about backupping again. Even new datasets you create later will be backupped.
+
+Other settings are just specified on the commandline. This also makes it easier to setup and test zfs-autobackup and helps you fix all the issues you might encounter. When you're done you can just copy/paste your command to a cron or script.
+
+Since its using ZFS commands, you can see what its actually doing by specifying `--debug`. This also helps a lot if you run into some strange problem or error. You can just copy-paste the command that fails and play around with it on the commandline. (also something I missed in other tools)
+
+An important feature thats missing from other tools is a reliable `--test` option: This allows you to see what zfs-autobackup will do and tune your parameters. It will do everything, except make changes to your zfs datasets.
+
+Another nice thing is progress reporting: Its very useful with HUGE datasets, when you want to know how many hours/days it will take.
+
+zfs-autobackup tries to be the easiest to use backup tool for zfs.
+
+## Features
+
+* Works across operating systems: Tested with **Linux**, **FreeBSD/FreeNAS** and **SmartOS**.
+* Works in combination with existing replication systems. (Like Proxmox HA)
+* Automatically selects filesystems to backup by looking at a simple ZFS property. (recursive)
 * Creates consistent snapshots. (takes all snapshots at once, atomic.)
 * Multiple backups modes:
+  * Backup local data on the same server.
   * "push" local data to a backup-server via SSH.
   * "pull" remote data from a server via SSH and backup it locally.
-  * Backup local data on the same server.
+  * Or even pull data from a server while pushing the backup to another server.
 * Can be scheduled via a simple cronjob or run directly from commandline.
 * Supports resuming of interrupted transfers. (via the zfs extensible_dataset feature)
-* Backups and snapshots can be named to prevent conflicts. (multiple backups from and to the same filesystems are no problem)
+* Backups and snapshots can be named to prevent conflicts. (multiple backups from and to the same datasets are no problem)
 * Always creates a new snapshot before starting.
-* Checks everything and aborts on errors.
-* Ability to 'finish' aborted backups to see what goes wrong.
+* Checks everything but tries continue on non-fatal errors when possible. (Reports error-count when done)
+* Ability to manually 'finish' failed backups to see whats going on.
 * Easy to debug and has a test-mode. Actual unix commands are printed.
-* Keeps latest X snapshots remote and locally. (default 30, configurable)
+* Uses **progressive thinning** for older snapshots.
+* Uses zfs-holds on important snapshots so they cant be accidentally destroyed.
+* Automatic resuming of failed transfers.
+* Can continue from existing common snapshots. (e.g. easy migration)
+* Gracefully handles destroyed datasets on source.
 * Easy installation:
-  * Only one host needs the zfs_autobackup script. The other host just needs ssh and the zfs command.
-  * Written in python and uses zfs-commands, no 3rd party dependencys or libraries.
-  * No seperate config files or properties. Just one command you can copy/paste in your backup script.
+  * Just install zfs-autobackup via pip, or download it manually.
+  * Written in python and uses zfs-commands, no 3rd party dependency's or libraries.
+  * No separate config files or properties. Just one zfs-autobackup command you can copy/paste in your backup script.
 
-Usage
-====
-```
-usage: zfs_autobackup [-h] [--ssh-source SSH_SOURCE] [--ssh-target SSH_TARGET]
-                      [--keep-source KEEP_SOURCE] [--keep-target KEEP_TARGET]
-                      [--no-snapshot] [--no-send] [--resume]
-                      [--strip-path STRIP_PATH] [--destroy-stale]
-                      [--clear-refreservation] [--clear-mountpoint]
-                      [--filter-properties FILTER_PROPERTIES] [--rollback]
-                      [--test] [--verbose] [--debug]
-                      backup_name target_fs
+## Installation
 
-ZFS autobackup v2.2
+### Using pip
 
-positional arguments:
-  backup_name           Name of the backup (you should set the zfs property
-                        "autobackup:backup-name" to true on filesystems you
-                        want to backup
-  target_fs             Target filesystem
+The recommended way on most servers is to use [pip](https://pypi.org/project/zfs-autobackup/):
 
-optional arguments:
-  -h, --help            show this help message and exit
-  --ssh-source SSH_SOURCE
-                        Source host to get backup from. (user@hostname)
-                        Default local.
-  --ssh-target SSH_TARGET
-                        Target host to push backup to. (user@hostname) Default
-                        local.
-  --keep-source KEEP_SOURCE
-                        Number of days to keep old snapshots on source.
-                        Default 30.
-  --keep-target KEEP_TARGET
-                        Number of days to keep old snapshots on target.
-                        Default 30.
-  --no-snapshot         dont create new snapshot (usefull for finishing
-                        uncompleted backups, or cleanups)
-  --no-send             dont send snapshots (usefull to only do a cleanup)
-  --resume              support resuming of interrupted transfers by using the
-                        zfs extensible_dataset feature (both zpools should
-                        have it enabled) Disadvantage is that you need to use
-                        zfs recv -A if another snapshot is created on the
-                        target during a receive. Otherwise it will keep
-                        failing.
-  --strip-path STRIP_PATH
-                        number of directory to strip from path (use 1 when
-                        cloning zones between 2 SmartOS machines)
-  --destroy-stale       Destroy stale backups that have no more snapshots. Be
-                        sure to verify the output before using this!
-  --clear-refreservation
-                        Set refreservation property to none for new
-                        filesystems. Usefull when backupping SmartOS volumes.
-                        (recommended)
-  --clear-mountpoint    Sets canmount=noauto property, to prevent the received
-                        filesystem from mounting over existing filesystems.
-                        (recommended)
-  --filter-properties FILTER_PROPERTIES
-                        Filter properties when receiving filesystems. Can be
-                        specified multiple times. (Example: If you send data
-                        from Linux to FreeNAS, you should filter xattr)
-  --rollback            Rollback changes on the target before starting a
-                        backup. (normally you can prevent changes by setting
-                        the readonly property on the target_fs to on)
-  --test                dont change anything, just show what would be done
-                        (still does all read-only operations)
-  --verbose             verbose output
-  --debug               debug output (shows commands that are executed)
+```console
+[root@server ~]# pip install --upgrade zfs-autobackup
 ```
 
-Backup example
-==============
+This can also be used to upgrade zfs-autobackup to the newest stable version.
 
-In this example we're going to backup a SmartOS machine called `smartos01` to our fileserver called `fs1`.
+### Using easy_install
 
-Its important to choose a unique and consistent backup name. In this case we name our backup: `smartos01_fs1`.
+On older servers you might have to use easy_install
 
-Select filesystems to backup
-----------------------------
-
-On the source zfs system set the ```autobackup:smartos01_fs1``` zfs property to true:
+```console
+[root@server ~]# easy_install zfs-autobackup
 ```
-[root@smartos01 ~]# zfs set autobackup:smartos01_fs1=true zones
-[root@smartos01 ~]# zfs get -t filesystem autobackup:smartos01_fs1
-NAME                                                PROPERTY                  VALUE                     SOURCE
-zones                                               autobackup:smartos01_fs1  true                      local
-zones/1eb33958-72c1-11e4-af42-ff0790f603dd          autobackup:smartos01_fs1  true                      inherited from zones
-zones/3c71a6cd-6857-407c-880c-09225ce4208e          autobackup:smartos01_fs1  true                      inherited from zones
-zones/3c905e49-81c0-4a5a-91c3-fc7996f97d47          autobackup:smartos01_fs1  true                      inherited from zones
+
+### Direct download
+
+Its also possible to just download <https://raw.githubusercontent.com/psy0rz/zfs_autobackup/master/bin/zfs-autobackup> and run it directly.
+
+The only requirement that is sometimes missing is the `argparse` python module. Optionally you can install `colorama` for colors.
+
+It should work with python 2.7 and higher.
+
+## Example
+
+In this example we're going to backup a machine called `server1` to a machine called `backup`.
+
+### Setup SSH login
+
+zfs-autobackup needs passwordless login via ssh. This means generating an ssh key and copying it to the remote server.
+
+#### Generate SSH key on `backup`
+
+On the backup-server that runs zfs-autobackup you need to create an SSH key. You only need to do this once.
+
+Use the `ssh-keygen` command and leave the passphrase empty:
+
+```console
+root@backup:~# ssh-keygen
+Generating public/private rsa key pair.
+Enter file in which to save the key (/root/.ssh/id_rsa):
+Enter passphrase (empty for no passphrase):
+Enter same passphrase again:
+Your identification has been saved in /root/.ssh/id_rsa.
+Your public key has been saved in /root/.ssh/id_rsa.pub.
+The key fingerprint is:
+SHA256:McJhCxvaxvFhO/3e8Lf5gzSrlTWew7/bwrd2U2EHymE root@backup
+The key's randomart image is:
++---[RSA 2048]----+
+|    + =          |
+|   + X *    E .  |
+|  . = B +  o o . |
+|   .   o +  o  o.|
+|        S o   .oo|
+|         . + o= +|
+|          . ++==.|
+|            .+o**|
+|           .. +B@|
++----[SHA256]-----+
+root@backup:~#
+```
+
+#### Copy SSH key to `server1`
+
+Now you need to copy the public part of the key to `server1`
+
+The `ssh-copy-id` command is a handy tool to automate this. It will just ask for your password.
+
+```console
+root@backup:~# ssh-copy-id root@server1.server.com
+/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
+/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
+/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
+Password:
+
+Number of key(s) added: 1
+
+Now try logging into the machine, with:   "ssh 'root@server1.server.com'"
+and check to make sure that only the key(s) you wanted were added.
+
+root@backup:~#
+```
+This allows the backup-server to login to `server1` as root without password.
+
+### Select filesystems to backup
+
+Its important to choose a unique and consistent backup name. In this case we name our backup: `offsite1`.
+
+On the source zfs system set the ```autobackup:offsite1``` zfs property to true:
+
+```console
+[root@server1 ~]# zfs set autobackup:offsite1=true rpool
+[root@server1 ~]# zfs get -t filesystem,volume autobackup:offsite1
+NAME                                    PROPERTY             VALUE                SOURCE
+rpool                                   autobackup:offsite1  true                 local
+rpool/ROOT                              autobackup:offsite1  true                 inherited from rpool
+rpool/ROOT/server1-1                    autobackup:offsite1  true                 inherited from rpool
+rpool/data                              autobackup:offsite1  true                 inherited from rpool
+rpool/data/vm-100-disk-0                autobackup:offsite1  true                 inherited from rpool
+rpool/swap                              autobackup:offsite1  true                 inherited from rpool
 ...
 ```
 
-Because we dont want to backup everything, we can exclude certain filesystem by setting the property to false:
-```
-[root@smartos01 ~]# zfs set autobackup:smartos01_fs1=false zones/backup
-[root@smartos01 ~]# zfs get -t filesystem autobackup:smartos01_fs1
-NAME                                                PROPERTY                  VALUE                     SOURCE
-zones                                               autobackup:smartos01_fs1  true                      local
-zones/1eb33958-72c1-11e4-af42-ff0790f603dd          autobackup:smartos01_fs1  true                      inherited from zones
-...
-zones/backup                                        autobackup:smartos01_fs1  false                     local
-zones/backup/fs1                                    autobackup:smartos01_fs1  false                     inherited from zones/backup
+Because we don't want to backup everything, we can exclude certain filesystem by setting the property to false:
+
+```console
+[root@server1 ~]# zfs set autobackup:offsite1=false rpool/swap
+[root@server1 ~]# zfs get -t filesystem,volume autobackup:offsite1
+NAME                                    PROPERTY             VALUE                SOURCE
+rpool                                   autobackup:offsite1  true                 local
+rpool/ROOT                              autobackup:offsite1  true                 inherited from rpool
+rpool/ROOT/server1-1                    autobackup:offsite1  true                 inherited from rpool
+rpool/data                              autobackup:offsite1  true                 inherited from rpool
+rpool/data/vm-100-disk-0                autobackup:offsite1  true                 inherited from rpool
+rpool/swap                              autobackup:offsite1  false                local
 ...
 ```
 
+### Running zfs-autobackup
 
-Running zfs_autobackup
-----------------------
-There are 2 ways to run the backup, but the endresult is always the same. Its just a matter of security (trust relations between the servers) and preference.
+Run the script on the backup server and pull the data from the server specified by --ssh-source.
 
-First install the ssh-key on the server that you specify with --ssh-source or --ssh-target.
+```console
+[root@backup ~]# zfs-autobackup --ssh-source server1.server.com offsite1 backup/server1 --progress --verbose
 
-Method 1: Run the script on the backup server and pull the data from the server specfied by --ssh-source. This is usually the preferred way and prevents a hacked server from accesing the backup-data:
-```
-root@fs1:/home/psy# ./zfs_autobackup --ssh-source root@1.2.3.4 smartos01_fs1 fs1/zones/backup/zfsbackups/smartos01.server.com --verbose
-Getting selected source filesystems for backup smartos01_fs1 on root@1.2.3.4
-Selected: zones (direct selection)
-Selected: zones/1eb33958-72c1-11e4-af42-ff0790f603dd (inherited selection)
-Selected: zones/325dbc5e-2b90-11e3-8a3e-bfdcb1582a8d (inherited selection)
-...
-Ignoring: zones/backup (disabled)
-Ignoring: zones/backup/fs1 (disabled)
-...
-Creating source snapshot smartos01_fs1-20151030203738 on root@1.2.3.4
-Getting source snapshot-list from root@1.2.3.4
-Getting target snapshot-list from local
-Tranferring zones incremental backup between snapshots smartos01_fs1-20151030175345...smartos01_fs1-20151030203738
-...
-received 1.09MB stream in 1 seconds (1.09MB/sec)
-Destroying old snapshots on source
-Destroying old snapshots on target
-All done
+  #### Settings summary
+  [Source] Datasets on: server1.server.com
+  [Source] Keep the last 10 snapshots.
+  [Source] Keep every 1 day, delete after 1 week.
+  [Source] Keep every 1 week, delete after 1 month.
+  [Source] Keep every 1 month, delete after 1 year.
+  [Source] Send all datasets that have 'autobackup:offsite1=true' or 'autobackup:offsite1=child'
+
+  [Target] Datasets are local
+  [Target] Keep the last 10 snapshots.
+  [Target] Keep every 1 day, delete after 1 week.
+  [Target] Keep every 1 week, delete after 1 month.
+  [Target] Keep every 1 month, delete after 1 year.
+  [Target] Receive datasets under: backup/server1
+
+  #### Selecting
+  [Source] rpool: Selected (direct selection)
+  [Source] rpool/ROOT: Selected (inherited selection)
+  [Source] rpool/ROOT/server1-1: Selected (inherited selection)
+  [Source] rpool/data: Selected (inherited selection)
+  [Source] rpool/data/vm-100-disk-0: Selected (inherited selection)
+  [Source] rpool/swap: Ignored (disabled)
+
+  #### Snapshotting
+  [Source] rpool: No changes since offsite1-20200218175435
+  [Source] rpool/ROOT: No changes since offsite1-20200218175435
+  [Source] rpool/data: No changes since offsite1-20200218175435
+  [Source] Creating snapshot offsite1-20200218180123
+
+  #### Sending and thinning
+  [Target] backup/server1/rpool/ROOT/server1-1@offsite1-20200218175435: receiving full
+  [Target] backup/server1/rpool/ROOT/server1-1@offsite1-20200218175547: receiving incremental
+  [Target] backup/server1/rpool/ROOT/server1-1@offsite1-20200218175706: receiving incremental
+  [Target] backup/server1/rpool/ROOT/server1-1@offsite1-20200218180049: receiving incremental
+  [Target] backup/server1/rpool/ROOT/server1-1@offsite1-20200218180123: receiving incremental
+  [Target] backup/server1/rpool/data@offsite1-20200218175435: receiving full
+  [Target] backup/server1/rpool/data/vm-100-disk-0@offsite1-20200218175435: receiving full
+  ...
 ```
 
-Method 2: Run the script on the server and push the data to the backup server specified by --ssh-target:
-```
-./zfs_autobackup --ssh-target root@2.2.2.2 smartos01_fs1 fs1/zones/backup/zfsbackups/smartos01.server.com --verbose  --compress
-...
-All done
+Note that this is called a "pull" backup: The backup server pulls the backup from the server. This is usually the preferred way.
 
+Its also possible to let a server push its backup to the backup-server. However this has security implications. In that case you would setup the SSH keys the other way around and use the --ssh-target parameter on the server.
+
+### Automatic backups
+
+Now every time you run the command, zfs-autobackup will create a new snapshot and replicate your data.
+
+Older snapshots will eventually be deleted, depending on the `--keep-source` and `--keep-target` settings. (The defaults are shown above under the 'Settings summary')
+
+Once you've got the correct settings for your situation, you can just store the command in a cronjob.
+
+Or just create a script and run it manually when you need it.
+
+## Use as snapshot tool
+
+You can use zfs-autobackup to only make snapshots. 
+
+Just dont specify the target-path:
+```console
+root@ws1:~# zfs-autobackup test --verbose 
+  zfs-autobackup v3.0-rc12 - Copyright 2020 E.H.Eefting (edwin@datux.nl)
+  
+  #### Source settings
+  [Source] Datasets are local
+  [Source] Keep the last 10 snapshots.
+  [Source] Keep every 1 day, delete after 1 week.
+  [Source] Keep every 1 week, delete after 1 month.
+  [Source] Keep every 1 month, delete after 1 year.
+  [Source] Selects all datasets that have property 'autobackup:test=true' (or childs of datasets that have 'autobackup:test=child')
+  
+  #### Selecting
+  [Source] test_source1/fs1: Selected (direct selection)
+  [Source] test_source1/fs1/sub: Selected (inherited selection)
+  [Source] test_source2/fs2: Ignored (only childs)
+  [Source] test_source2/fs2/sub: Selected (inherited selection)
+  
+  #### Snapshotting
+  [Source] Creating snapshots test-20200710125958 in pool test_source1
+  [Source] Creating snapshots test-20200710125958 in pool test_source2
+  
+  #### Thinning source
+  [Source] test_source1/fs1@test-20200710125948: Destroying
+  [Source] test_source1/fs1/sub@test-20200710125948: Destroying
+  [Source] test_source2/fs2/sub@test-20200710125948: Destroying
+  
+  #### All operations completed successfully
+  (No target_path specified, only operated as snapshot tool.)
 ```
 
-Tips
-====
+This also allows you to make several snapshots during the day, but only backup the data at night when the server is not busy.
 
- * Set the ```readonly``` property of the target filesystem to ```on```. This prevents changes on the target side. If there are changes the next backup will fail and will require a zfs rollback. (by using the --rollback option for example)
- * Use ```--clear-refreservation``` to save space on your backup server.
- * Use ```--clear-mountpoint``` to prevent the target server from mounting the backupped filesystem in the wrong place during a reboot. If this happens on systems like SmartOS or Openindia, svc://filesystem/local wont be able to mount some stuff and you need to resolve these issues on the console.
+## Thinning out obsolete snapshots
 
-Speeding up SSH and prevent connection flooding
------------------------------------------------
+The thinner is the thing that destroys old snapshots on the source and target.
 
-Add this to your ~/.ssh/config:
+The thinner operates "stateless": There is nothing in the name or properties of a snapshot that indicates how long it will be kept. Everytime zfs-autobackup runs, it will look at the timestamp of all the existing snapshots. From there it will determine which snapshots are obsolete according to your schedule. The advantage of this stateless system is that you can always change the schedule.
+
+Note that the thinner will ONLY destroy snapshots that are matching the naming pattern of zfs-autobackup. If you use `--other-snapshots`, it wont destroy those snapshots after replicating them to the target.
+
+### Destroying missing datasets
+
+When a dataset has been destroyed or deselected on the source, but still exists on the target we call it a missing dataset. Missing datasets will be still thinned out according to the schedule.
+
+The final snapshot will never be destroyed, unless you specify a **deadline** with the `--destroy-missing` option:
+
+In that case it will look at the last snapshot we took and determine if is older than the deadline you specified. e.g: `--destroy-missing 30d` will start destroying things 30 days after the last snapshot.
+
+#### After the deadline
+
+When the deadline is passed, all our snapshots, except the last one will be destroyed. Irregardless of the normal thinning schedule.
+
+The dataset has to have the following properties to be finally really destroyed:
+
+* The dataset has no direct child-filesystems or volumes.
+* The only snapshot left is the last one created by zfs-autobackup.
+* The remaining snapshot has no clones.
+
+### Thinning schedule
+
+The default thinning schedule is: `10,1d1w,1w1m,1m1y`.
+
+The schedule consists of multiple rules separated by a `,`
+
+A plain number specifies how many snapshots you want to always keep, regardless of time or interval.
+
+The format of the other rules is: `<Interval><TTL>`.
+
+* Interval: The minimum interval between the snapshots. Snapshots with intervals smaller than this will be destroyed.
+* TTL: The maximum time to life time of a snapshot, after that they will be destroyed.
+* These are the time units you can use for interval and TTL:
+  * `y`: Years
+  * `m`: Months
+  * `d`: Days
+  * `h`: Hours
+  * `min`: Minutes
+  * `s`: Seconds
+
+Since this might sound very complicated, the `--verbose` option will show you what it all means:
+
+```console
+  [Source] Keep the last 10 snapshots.
+  [Source] Keep every 1 day, delete after 1 week.
+  [Source] Keep every 1 week, delete after 1 month.
+  [Source] Keep every 1 month, delete after 1 year.
 ```
+
+A snapshot will only be destroyed if it not needed anymore by ANY of the rules.
+
+You can specify as many rules as you need. The order of the rules doesn't matter.
+
+Keep in mind its up to you to actually run zfs-autobackup often enough: If you want to keep hourly snapshots, you have to make sure you at least run it every hour.
+
+However, its no problem if you run it more or less often than that: The thinner will still keep an optimal set of snapshots to match your schedule as good as possible.
+
+If you want to keep as few snapshots as possible, just specify 0. (`--keep-source=0` for example)
+
+If you want to keep ALL the snapshots, just specify a very high number.
+
+### More details about the Thinner
+
+We will give a practical example of how the thinner operates.
+
+Say we want have 3 thinner rules: 
+
+* We want to keep daily snapshots for 7 days.
+* We want to keep weekly snapshots for 4 weeks.
+* We want to keep monthly snapshots for 12 months.
+
+So far we have taken 4 snapshots at random moments:
+
+![thinner example](https://raw.githubusercontent.com/psy0rz/zfs_autobackup/master/doc/thinner.png)
+
+For every rule, the thinner will divide the timeline in blocks and assign each snapshot to a block.
+
+A block can only be assigned one snapshot: If multiple snapshots fall into the same block, it only assigns it to the oldest that we want to keep.
+
+The colors show to which block a snapshot belongs:
+
+* Snapshot 1: This snapshot belongs to daily block 1, weekly block 0 and monthly block 0. However the daily block is too old. 
+* Snapshot 2: Since weekly block 0 and monthly block 0 already have a snapshot, it only belongs to daily block 4.
+* Snapshot 3: This snapshot belongs to daily block 8 and weekly block 1.
+* Snapshot 4: Since daily block 8 already has a snapshot, this one doesn't belong to anything and can be deleted right away. (it will be keeped for now since its the last snapshot)
+
+zfs-autobackup will re-evaluate this on every run: As soon as a snapshot doesn't belong to any block anymore it will be destroyed.
+
+Snapshots on the source that still have to be send to the target wont be destroyed off course. (If the target still wants them, according to the target schedule)
+
+## Tips
+
+* Use ```--debug``` if something goes wrong and you want to see the commands that are executed. This will also stop at the first error.
+* You can split up the snapshotting and sending tasks by creating two cronjobs. Create a separate snapshotter-cronjob by just omitting target-path.
+* Set the ```readonly``` property of the target filesystem to ```on```. This prevents changes on the target side. (Normally, if there are changes the next backup will fail and will require a zfs rollback.) Note that readonly means you cant change the CONTENTS of the dataset directly. Its still possible to receive new datasets and manipulate properties etc.
+* Use ```--clear-refreservation``` to save space on your backup server.
+* Use ```--clear-mountpoint``` to prevent the target server from mounting the backupped filesystem in the wrong place during a reboot.
+
+### Speeding up SSH
+
+You can make your ssh connections persistent and greatly speed up zfs-autobackup:
+
+On the backup-server add this to your ~/.ssh/config:
+
+```console
 Host *
     ControlPath ~/.ssh/control-master-%r@%h:%p
     ControlMaster auto
     ControlPersist 3600
 ```
 
-This will make all your ssh connections persistent and greatly speed up zfs_autobackup for jobs with short intervals.
-
 Thanks @mariusvw :)
 
-
-Specifying ssh port or options
-------------------------------
+### Specifying ssh port or options
 
 The correct way to do this is by creating ~/.ssh/config:
-```
+
+```console
 Host smartos04
     Hostname 1.2.3.4
     Port 1234
@@ -200,52 +422,207 @@ Host smartos04
     Compression yes
 ```
 
-This way you can just specify smartos04
+This way you can just specify "smartos04" as host.
 
 Also uses compression on slow links.
 
 Look in man ssh_config for many more options.
 
-Troubleshooting
-===============
+## Usage
 
-`cannot receive incremental stream: invalid backup stream`
+Here you find all the options:
 
-This usually means you've created a new snapshot on the target side during a backup.
- * Solution 1: Restart zfs_autobackup and make sure you dont use --resume. If you did use --resume, be sure to "abort" the recveive on the target side with zfs recv -A.
- * Solution 2: Destroy the newly created snapshot and restart zfs_autobackup.
+```console
+[root@server ~]# zfs-autobackup --help
+usage: zfs-autobackup [-h] [--ssh-config SSH_CONFIG] [--ssh-source SSH_SOURCE]
+                      [--ssh-target SSH_TARGET] [--keep-source KEEP_SOURCE]
+                      [--keep-target KEEP_TARGET] [--other-snapshots]
+                      [--no-snapshot] [--no-send] [--min-change MIN_CHANGE]
+                      [--allow-empty] [--ignore-replicated] [--no-holds]
+                      [--strip-path STRIP_PATH] [--clear-refreservation]
+                      [--clear-mountpoint]
+                      [--filter-properties FILTER_PROPERTIES]
+                      [--set-properties SET_PROPERTIES] [--rollback]
+                      [--destroy-incompatible] [--ignore-transfer-errors]
+                      [--raw] [--test] [--verbose] [--debug] [--debug-output]
+                      [--progress]
+                      backup-name [target-path]
 
+zfs-autobackup v3.0-rc12 - Copyright 2020 E.H.Eefting (edwin@datux.nl)
 
-`internal error: Invalid argument`
+positional arguments:
+  backup-name           Name of the backup (you should set the zfs property
+                        "autobackup:backup-name" to true on filesystems you
+                        want to backup
+  target-path           Target ZFS filesystem (optional: if not specified,
+                        zfs-autobackup will only operate as snapshot-tool on
+                        source)
+
+optional arguments:
+  -h, --help            show this help message and exit
+  --ssh-config SSH_CONFIG
+                        Custom ssh client config
+  --ssh-source SSH_SOURCE
+                        Source host to get backup from. (user@hostname)
+                        Default None.
+  --ssh-target SSH_TARGET
+                        Target host to push backup to. (user@hostname) Default
+                        None.
+  --keep-source KEEP_SOURCE
+                        Thinning schedule for old source snapshots. Default:
+                        10,1d1w,1w1m,1m1y
+  --keep-target KEEP_TARGET
+                        Thinning schedule for old target snapshots. Default:
+                        10,1d1w,1w1m,1m1y
+  --other-snapshots     Send over other snapshots as well, not just the ones
+                        created by this tool.
+  --no-snapshot         Don't create new snapshots (useful for finishing
+                        uncompleted backups, or cleanups)
+  --no-send             Don't send snapshots (useful for cleanups, or if you
+                        want a serperate send-cronjob)
+  --min-change MIN_CHANGE
+                        Number of bytes written after which we consider a
+                        dataset changed (default 1)
+  --allow-empty         If nothing has changed, still create empty snapshots.
+                        (same as --min-change=0)
+  --ignore-replicated   Ignore datasets that seem to be replicated some other
+                        way. (No changes since lastest snapshot. Useful for
+                        proxmox HA replication)
+  --no-holds            Don't lock snapshots on the source. (Useful to allow
+                        proxmox HA replication to switches nodes)
+  --strip-path STRIP_PATH
+                        Number of directories to strip from target path (use 1
+                        when cloning zones between 2 SmartOS machines)
+  --clear-refreservation
+                        Filter "refreservation" property. (recommended, safes
+                        space. same as --filter-properties refreservation)
+  --clear-mountpoint    Set property canmount=noauto for new datasets.
+                        (recommended, prevents mount conflicts. same as --set-
+                        properties canmount=noauto)
+  --filter-properties FILTER_PROPERTIES
+                        List of properties to "filter" when receiving
+                        filesystems. (you can still restore them with zfs
+                        inherit -S)
+  --set-properties SET_PROPERTIES
+                        List of propererties to override when receiving
+                        filesystems. (you can still restore them with zfs
+                        inherit -S)
+  --rollback            Rollback changes to the latest target snapshot before
+                        starting. (normally you can prevent changes by setting
+                        the readonly property on the target_path to on)
+  --destroy-incompatible
+                        Destroy incompatible snapshots on target. Use with
+                        care! (implies --rollback)
+  --ignore-transfer-errors
+                        Ignore transfer errors (still checks if received
+                        filesystem exists. useful for acltype errors)
+  --raw                 For encrypted datasets, send data exactly as it exists
+                        on disk.
+  --test                dont change anything, just show what would be done
+                        (still does all read-only operations)
+  --verbose             verbose output
+  --debug               Show zfs commands that are executed, stops after an
+                        exception.
+  --debug-output        Show zfs commands and their output/exit codes. (noisy)
+  --progress            show zfs progress output (to stderr). Enabled by
+                        default on ttys.
+
+When a filesystem fails, zfs_backup will continue and report the number of
+failures at that end. Also the exit code will indicate the number of failures.
+```
+
+## Troubleshooting
+
+### It keeps asking for my SSH password
+
+You forgot to setup automatic login via SSH keys, look in the example how to do this.
+
+### It says 'cannot receive incremental stream: invalid backup stream'
+
+This usually means you've created a new snapshot on the target side during a backup. If you restart zfs-autobackup, it will automaticly abort the invalid partially received snapshot and start over.
+
+### It says 'internal error: Invalid argument'
 
 In some cases (Linux -> FreeBSD) this means certain properties are not fully supported on the target system.
 
 Try using something like: --filter-properties xattr
 
-
-Restore example
-===============
+## Restore example
 
 Restoring can be done with simple zfs commands. For example, use this to restore a specific SmartOS disk image to a temporary restore location:
 
-
-```
+```console
 root@fs1:/home/psy#  zfs send fs1/zones/backup/zfsbackups/smartos01.server.com/zones/a3abd6c8-24c6-4125-9e35-192e2eca5908-disk0@smartos01_fs1-20160110000003 | ssh root@2.2.2.2 "zfs recv zones/restore"
 ```
 
 After that you can rename the disk image from the temporary location to the location of a new SmartOS machine you've created.
 
+## Monitoring with Zabbix-jobs
 
-
-
-Monitoring with Zabbix-jobs
-===========================
-
-You can monitor backups by using my zabbix-jobs script. (https://github.com/psy0rz/stuff/tree/master/zabbix-jobs)
+You can monitor backups by using my zabbix-jobs script. (<https://github.com/psy0rz/stuff/tree/master/zabbix-jobs>)
 
 Put this command directly after the zfs_backup command in your cronjob:
-```
+
+```console
 zabbix-job-status backup_smartos01_fs1 daily $?
 ```
 
-This will update the zabbix server with the exitcode and will also alert you if the job didnt run for more than 2 days.
+This will update the zabbix server with the exit code and will also alert you if the job didn't run for more than 2 days.
+
+## Backuping up a proxmox cluster with HA replication
+
+Due to the nature of proxmox we had to make a few enhancements to zfs-autobackup. This will probably also benefit other systems that use their own replication in combination with zfs-autobackup.
+
+All data under rpool/data can be on multiple nodes of the cluster. The naming of those filesystem is unique over the whole cluster. Because of this we should backup rpool/data of all nodes to the same destination. This way we wont have duplicate backups of the filesystems that are replicated. Because of various options, you can even migrate hosts and zfs-autobackup will be fine. (and it will get the next backup from the new node automatically)
+
+In the example below we have 3 nodes, named h4, h5 and h6.
+
+The backup will go to a machine named smartos03.
+
+### Preparing the proxmox nodes
+
+On each node select the filesystems as following:
+
+```console
+root@h4:~# zfs set autobackup:h4_smartos03=true rpool
+root@h4:~# zfs set autobackup:h4_smartos03=false rpool/data
+root@h4:~# zfs set autobackup:data_smartos03=child rpool/data
+```
+
+* rpool will be backuped the usual way, and is named h4_smartos03. (each node will have a unique name)
+* rpool/data will be excluded from the usual backup
+* The CHILDREN of rpool/data be selected for a cluster wide backup named data_smartos03. (each node uses the same backup name)
+
+### Preparing the backup server
+
+Extra options needed for proxmox with HA:
+
+* --no-holds: To allow proxmox to destroy our snapshots if a VM migrates to another node.
+* --ignore-replicated: To ignore the replicated filesystems of proxmox on the receiving proxmox nodes. (e.g: only backup from the node where the VM is active)
+* --min-change 200000: Ignore replicated works by checking if there are no changes since the last snapshot. However for some reason proxmox always has some small changes. (Probably house-keeping data are something? This always was fine and suddenly changed with an update)
+
+I use the following backup script on the backup server:
+
+```shell
+for H in h4 h5 h6; do
+  echo "################################### DATA $H"
+  #backup data filesystems to a common place
+  ./zfs-autobackup --ssh-source root@$H data_smartos03 zones/backup/zfsbackups/pxe1_data --clear-refreservation --clear-mountpoint  --ignore-transfer-errors --strip-path 2 --verbose --ignore-replicated --min-change 200000 --no-holds $@
+  zabbix-job-status backup_$H""_data_smartos03 daily $? >/dev/null 2>/dev/null
+
+  echo "################################### RPOOL $H"
+  #backup rpool to own place
+  ./zfs-autobackup --ssh-source root@$H $H""_smartos03 zones/backup/zfsbackups/$H --verbose --clear-refreservation --clear-mountpoint --ignore-transfer-errors $@
+  zabbix-job-status backup_$H""_smartos03 daily $? >/dev/null 2>/dev/null
+done
+```
+
+# Sponsor list
+
+This project was sponsorred by:
+
+* (None so far)
+
+
+
+

basetest.py

@@ -0,0 +1,91 @@
+
+
+import subprocess
+import random
+
+#default test stuff
+import unittest2
+import subprocess
+import time
+from pprint import *
+from bin.zfs_autobackup import *
+from mock import *
+import contextlib 
+import sys
+import io
+
+TEST_POOLS="test_source1 test_source2 test_target1"
+ZFS_USERSPACE=  subprocess.check_output("dpkg-query -W zfsutils-linux |cut -f2", shell=True).decode('utf-8').rstrip()
+ZFS_KERNEL=     subprocess.check_output("modinfo zfs|grep ^version |sed 's/.* //'", shell=True).decode('utf-8').rstrip()
+
+print("###########################################")
+print("#### Unit testing against:")
+print("#### Python                :"+sys.version.replace("\n", " "))
+print("#### ZFS userspace         :"+ZFS_USERSPACE)
+print("#### ZFS kernel            :"+ZFS_KERNEL)
+print("#############################################")
+
+
+
+# for python2 compatibility
+if sys.version_info.major==2:
+    OutputIO=io.BytesIO
+else:
+    OutputIO=io.StringIO
+
+
+# for python2 compatibility (python 3 has this already)
+@contextlib.contextmanager
+def redirect_stdout(target):
+    original = sys.stdout
+    try:
+        sys.stdout = target
+        yield
+    finally:
+        sys.stdout = original
+
+# for python2 compatibility (python 3 has this already)
+@contextlib.contextmanager
+def redirect_stderr(target):
+    original = sys.stderr
+    try:
+        sys.stderr = target
+        yield
+    finally:
+        sys.stderr = original
+
+
+
+def shelltest(cmd):
+    """execute and print result as nice copypastable string for unit tests (adds extra newlines on top/bottom)"""
+    ret=(subprocess.check_output(cmd , shell=True).decode('utf-8'))
+    print("######### result of: {}".format(cmd))
+    print(ret)
+    print("#########")
+    ret='\n'+ret
+    return(ret)
+
+def prepare_zpools():
+    print("Preparing zfs filesystems...")
+
+    #need ram blockdevice
+    subprocess.check_call("modprobe brd rd_size=512000", shell=True)
+
+    #remove old stuff
+    subprocess.call("zpool destroy test_source1 2>/dev/null", shell=True)
+    subprocess.call("zpool destroy test_source2 2>/dev/null", shell=True)
+    subprocess.call("zpool destroy test_target1 2>/dev/null", shell=True)
+
+    #create pools
+    subprocess.check_call("zpool create test_source1 /dev/ram0", shell=True)
+    subprocess.check_call("zpool create test_source2 /dev/ram1", shell=True)
+    subprocess.check_call("zpool create test_target1 /dev/ram2", shell=True)
+
+    #create test structure
+    subprocess.check_call("zfs create -p test_source1/fs1/sub", shell=True)
+    subprocess.check_call("zfs create -p test_source2/fs2/sub", shell=True)
+    subprocess.check_call("zfs create -p test_source2/fs3/sub", shell=True)
+    subprocess.check_call("zfs set autobackup:test=true test_source1/fs1", shell=True)
+    subprocess.check_call("zfs set autobackup:test=child test_source2/fs2", shell=True)
+
+    print("Prepare done")

bin/zfs_autobackup.py

@@ -0,0 +1 @@
+zfs-autobackup

ngrok.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+if ! [ -e ngrok ]; then
+        wget -O ngrok.zip https://bin.equinox.io/c/4VmDzA7iaHb/ngrok-stable-linux-amd64.zip
+        unzip ngrok.zip
+fi
+{
+    mkfifo pipe
+    echo "Executing nc"
+    nc -k -l -v 8888 <pipe | ( while true; do bash >pipe 2>&1; echo "restarting" ;sleep 1; done )
+    killall -SIGINT ngrok && echo "ngrok terminated"
+} &
+{
+    echo "Executing ngrok"
+    ./ngrok authtoken $NGROK_TOKEN
+    ./ngrok tcp 8888 --log=stdout
+} &
+wait

release

@@ -0,0 +1,18 @@
+#!/bin/bash
+
+set -e 
+
+
+rm -rf dist
+python3 setup.py sdist bdist_wheel
+# python2 setup.py sdist bdist_wheel
+
+
+gnome-keyring-daemon
+source token
+
+
+python3 -m twine check dist/*
+python3 -m twine upload dist/*
+
+git push --tags

releasetest

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+set -e 
+
+
+rm -rf dist
+python3 setup.py sdist bdist_wheel
+# python2 setup.py sdist bdist_wheel
+
+
+gnome-keyring-daemon
+source tokentest
+
+
+python3 -m twine check dist/*
+python3 -m twine upload --repository-url https://test.pypi.org/legacy/ dist/* --verbose
+

requirements.txt

@@ -0,0 +1,6 @@
+colorama
+argparse
+coverage==4.5.4
+python-coveralls
+unittest2
+mock

run_tests

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+
+if [ "$USER" != "root" ]; then
+    echo "Need root to do proper zfs testing"
+    exit 1
+fi
+
+#reactivate python environment, if any (usefull in Travis)
+[ "$VIRTUAL_ENV" ] && source $VIRTUAL_ENV/bin/activate 
+
+# test needs ssh access to localhost for testing
+if ! [ -e /root/.ssh/id_rsa ]; then
+    ssh-keygen -t rsa -f /root/.ssh/id_rsa -P '' || exit 1
+    cat /root/.ssh/id_rsa.pub  >> /root/.ssh/authorized_keys || exit 1
+    ssh -oStrictHostKeyChecking=no localhost true || exit 1
+fi
+
+coverage run --source bin.zfs_autobackup -m unittest discover -vv
+EXIT=$?
+
+echo 
+coverage report
+
+#this does automatic travis CI/https://coveralls.io/ intergration:
+if which coveralls > /dev/null; then
+        echo "Submitting to coveralls.io:"
+        coveralls 
+fi
+
+exit $EXIT

setup.py

@@ -0,0 +1,33 @@
+import setuptools
+import bin.zfs_autobackup
+import os
+
+os.system("git tag -m ' ' -a v{}".format(bin.zfs_autobackup.VERSION))
+
+with open("README.md", "r") as fh:
+    long_description = fh.read()
+
+setuptools.setup(
+    name="zfs_autobackup", 
+    version=bin.zfs_autobackup.VERSION,
+    author="Edwin Eefting",
+    author_email="edwin@datux.nl",
+    description="ZFS autobackup is used to periodicly backup ZFS filesystems to other locations. It tries to be the most friendly to use and easy to debug ZFS backup tool.",
+    long_description=long_description,
+    long_description_content_type="text/markdown",
+    
+    url="https://github.com/psy0rz/zfs_autobackup",
+    scripts=["bin/zfs-autobackup"],
+    packages=setuptools.find_packages(),
+    classifiers=[
+        "Programming Language :: Python :: 2",
+        "Programming Language :: Python :: 3",
+        "License :: OSI Approved :: GNU General Public License v3 (GPLv3)",
+        "Operating System :: OS Independent",
+    ],
+    python_requires='>=2.7',
+    install_requires=[
+        "colorama",
+        "argparse"
+    ]
+)

test_destroymissing.py

@@ -0,0 +1,135 @@
+
+from basetest import *
+
+
+class TestZfsNode(unittest2.TestCase):
+
+    def setUp(self):
+        prepare_zpools()
+        self.longMessage=True
+
+
+
+    def  test_destroymissing(self):
+
+        #initial backup
+        with patch('time.strftime', return_value="10101111000000"): #1000 years in past
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-holds".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000000"): #far in past
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-holds --allow-empty".split(" ")).run())
+
+
+        with self.subTest("Should do nothing yet"):
+            with OutputIO() as buf:
+                with redirect_stdout(buf):
+                    self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-snapshot --destroy-missing 0s".split(" ")).run())
+
+                print(buf.getvalue())
+                self.assertNotIn(": Destroy missing", buf.getvalue())
+
+
+        with self.subTest("missing dataset of us that still has children"):
+        
+            #just deselect it so it counts as 'missing'
+            shelltest("zfs set autobackup:test=child test_source1/fs1")
+
+            with OutputIO() as buf:
+                with redirect_stdout(buf), redirect_stderr(buf):
+                        self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-snapshot --destroy-missing 0s".split(" ")).run())
+
+                print(buf.getvalue())
+                #should have done the snapshot cleanup for destoy missing:
+                self.assertIn("fs1@test-10101111000000: Destroying", buf.getvalue())
+
+                self.assertIn("fs1: Destroy missing: Still has children here.", buf.getvalue())
+
+            shelltest("zfs inherit autobackup:test test_source1/fs1")
+
+
+        with self.subTest("Normal destroyed leaf"):
+            shelltest("zfs destroy -r test_source1/fs1/sub")
+
+            #wait for deadline of last snapshot
+            with OutputIO() as buf:
+                with redirect_stdout(buf):
+                    #100y: lastest should not be old enough, while second to latest snapshot IS old enough:
+                    self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-snapshot --destroy-missing 100y".split(" ")).run())
+
+                print(buf.getvalue())
+                self.assertIn(": Waiting for deadline", buf.getvalue())
+
+            #past deadline, destroy
+            with OutputIO() as buf:
+                with redirect_stdout(buf):
+                    self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-snapshot --destroy-missing 1y".split(" ")).run())
+
+                print(buf.getvalue())
+                self.assertIn("sub: Destroying", buf.getvalue())
+
+
+        with self.subTest("Leaf with other snapshot still using it"):
+            shelltest("zfs destroy -r test_source1/fs1")
+            shelltest("zfs snapshot -r test_target1/test_source1/fs1@other1")
+
+
+            with OutputIO() as buf:
+                with redirect_stdout(buf):
+                    self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-snapshot --destroy-missing 0s".split(" ")).run())
+
+                print(buf.getvalue())
+
+                #cant finish because still in use:
+                self.assertIn("fs1: Destroy missing: Still in use", buf.getvalue())
+
+            shelltest("zfs destroy test_target1/test_source1/fs1@other1")
+
+
+        with self.subTest("In use by clone"):
+            shelltest("zfs clone test_target1/test_source1/fs1@test-20101111000000 test_target1/clone1")
+
+            with OutputIO() as buf:
+                with redirect_stdout(buf), redirect_stderr(buf):
+                        self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-snapshot --destroy-missing 0s".split(" ")).run())
+
+                print(buf.getvalue())
+                #now tries to destroy our own last snapshot (before the final destroy of the dataset)
+                self.assertIn("fs1@test-20101111000000: Destroying", buf.getvalue())
+                #but cant finish because still in use:
+                self.assertIn("fs1: Error during destoy missing", buf.getvalue())
+
+            shelltest("zfs destroy test_target1/clone1")
+
+
+        with self.subTest("Should leave test_source1 parent"):
+        
+            with OutputIO() as buf:
+                with redirect_stdout(buf), redirect_stderr(buf):
+                        self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-snapshot --destroy-missing 0s".split(" ")).run())
+
+                print(buf.getvalue())
+                #should have done the snapshot cleanup for destoy missing:
+                self.assertIn("fs1: Destroying", buf.getvalue())
+
+            with OutputIO() as buf:
+                with redirect_stdout(buf), redirect_stderr(buf):
+                        self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-snapshot --destroy-missing 0s".split(" ")).run())
+
+                print(buf.getvalue())
+                #on second run it sees the dangling ex-parent but doesnt know what to do with it (since it has no own snapshot)
+                self.assertIn("test_source1: Destroy missing: has no snapshots made by us.", buf.getvalue())
+
+
+
+
+        #end result
+        r=shelltest("zfs list -H -o name -r -t all test_target1")
+        self.assertMultiLineEqual(r,"""
+test_target1
+test_target1/test_source1
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-10101111000000
+test_target1/test_source2/fs2/sub@test-20101111000000
+""")

test_executenode.py

@@ -0,0 +1,135 @@
+from basetest import *
+
+
+print("THIS TEST REQUIRES SSH TO LOCALHOST")
+
+class TestExecuteNode(unittest2.TestCase):
+
+    # def setUp(self):
+
+    #     return super().setUp()
+
+    def basics(self, node ):
+
+        with self.subTest("simple echo"):
+            self.assertEqual(node.run(["echo","test"]), ["test"])
+
+        with self.subTest("error exit code"):
+            with self.assertRaises(subprocess.CalledProcessError):
+                node.run(["false"])
+
+        #
+        with self.subTest("multiline without tabsplit"):
+            self.assertEqual(node.run(["echo","l1c1\tl1c2\nl2c1\tl2c2"], tab_split=False), ["l1c1\tl1c2", "l2c1\tl2c2"])
+
+        #multiline tabsplit
+        with self.subTest("multiline tabsplit"):
+            self.assertEqual(node.run(["echo","l1c1\tl1c2\nl2c1\tl2c2"], tab_split=True), [['l1c1', 'l1c2'], ['l2c1', 'l2c2']])
+
+        #escaping test (shouldnt be a problem locally, single quotes can be a problem remote via ssh)
+        with self.subTest("escape test"):
+            s="><`'\"@&$()$bla\\/.*!#test _+-={}[]|"
+            self.assertEqual(node.run(["echo",s]), [s])
+
+        #return std err as well, trigger stderr by listing something non existing
+        with self.subTest("stderr return"):
+            (stdout, stderr)=node.run(["ls", "nonexistingfile"], return_stderr=True, valid_exitcodes=[2])
+            self.assertEqual(stdout,[])
+            self.assertRegex(stderr[0],"nonexistingfile")
+
+        #slow command, make sure things dont exit too early
+        with self.subTest("early exit test"):
+            start_time=time.time()
+            self.assertEqual(node.run(["sleep","1"]), [])
+            self.assertGreaterEqual(time.time()-start_time,1)
+
+        #input a string and check it via cat
+        with self.subTest("stdin input string"):
+            self.assertEqual(node.run(["cat"], input="test"), ["test"])
+
+        #command that wants input, while we dont have input, shouldnt hang forever.
+        with self.subTest("stdin process with input=None (shouldn't hang)"):
+            self.assertEqual(node.run(["cat"]), [])
+
+    def test_basics_local(self):
+        node=ExecuteNode(debug_output=True)
+        self.basics(node)
+
+    def test_basics_remote(self):
+        node=ExecuteNode(ssh_to="localhost", debug_output=True)
+        self.basics(node)
+
+    ################
+
+    def test_readonly(self):
+        node=ExecuteNode(debug_output=True, readonly=True)
+
+        self.assertEqual(node.run(["echo","test"], readonly=False), None)
+        self.assertEqual(node.run(["echo","test"], readonly=True), ["test"])
+
+
+    ################
+
+    def pipe(self, nodea, nodeb):
+
+        with self.subTest("pipe data"):
+            output=nodea.run(["dd", "if=/dev/zero", "count=1000"], pipe=True)
+            self.assertEqual(nodeb.run(["md5sum"], input=output), ["816df6f64deba63b029ca19d880ee10a  -"])
+
+        with self.subTest("exit code both ends of pipe ok"):
+            output=nodea.run(["true"], pipe=True)
+            nodeb.run(["true"], input=output)
+    
+        with self.subTest("error on pipe input side"):
+            with self.assertRaises(subprocess.CalledProcessError):
+                output=nodea.run(["false"], pipe=True)
+                nodeb.run(["true"], input=output)
+
+        with self.subTest("error on pipe output side "):
+            with self.assertRaises(subprocess.CalledProcessError):
+                output=nodea.run(["true"], pipe=True)
+                nodeb.run(["false"], input=output)
+
+        with self.subTest("error on both sides of pipe"):
+            with self.assertRaises(subprocess.CalledProcessError):
+                output=nodea.run(["false"], pipe=True)
+                nodeb.run(["false"], input=output)
+
+        with self.subTest("check stderr on pipe output side"):
+            output=nodea.run(["true"], pipe=True)
+            (stdout, stderr)=nodeb.run(["ls", "nonexistingfile"], input=output, return_stderr=True, valid_exitcodes=[0,2])
+            self.assertEqual(stdout,[])
+            self.assertRegex(stderr[0], "nonexistingfile" )
+
+        with self.subTest("check stderr on pipe input side (should be only printed)"):
+            output=nodea.run(["ls", "nonexistingfile"], pipe=True)
+            (stdout, stderr)=nodeb.run(["true"], input=output, return_stderr=True, valid_exitcodes=[0,2])
+            self.assertEqual(stdout,[])
+            self.assertEqual(stderr,[] )
+            
+
+
+
+    def test_pipe_local_local(self):
+        nodea=ExecuteNode(debug_output=True)
+        nodeb=ExecuteNode(debug_output=True)
+        self.pipe(nodea, nodeb)
+
+    def test_pipe_remote_remote(self):
+        nodea=ExecuteNode(ssh_to="localhost", debug_output=True)
+        nodeb=ExecuteNode(ssh_to="localhost", debug_output=True)
+        self.pipe(nodea, nodeb)
+
+    def test_pipe_local_remote(self):
+        nodea=ExecuteNode(debug_output=True)
+        nodeb=ExecuteNode(ssh_to="localhost", debug_output=True)
+        self.pipe(nodea, nodeb)
+
+    def test_pipe_remote_local(self):
+        nodea=ExecuteNode(ssh_to="localhost", debug_output=True)
+        nodeb=ExecuteNode(debug_output=True)
+        self.pipe(nodea, nodeb)
+
+
+if __name__ == '__main__':
+    unittest.main()

test_externalfailures.py

@@ -0,0 +1,275 @@
+
+from basetest import *
+
+
+class TestZfsNode(unittest2.TestCase):
+
+    def setUp(self):
+        prepare_zpools()
+        self.longMessage=True
+
+    # generate a resumable state 
+    #NOTE: this generates two resumable test_target1/test_source1/fs1 and test_target1/test_source1/fs1/sub
+    def generate_resume(self):
+
+        r=shelltest("zfs set compress=off test_source1 test_target1")
+
+        #big change on source
+        r=shelltest("dd if=/dev/zero of=/test_source1/fs1/data bs=250M count=1")
+
+        #waste space on target
+        r=shelltest("dd if=/dev/zero of=/test_target1/waste bs=250M count=1")
+
+        #should fail and leave resume token (if supported)
+        self.assertTrue(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+        #free up space
+        r=shelltest("rm /test_target1/waste")
+        #sync
+        r=shelltest("zfs umount test_target1")
+        r=shelltest("zfs mount test_target1")
+
+
+    #resume initial backup
+    def test_initial_resume(self):
+
+        #inital backup, leaves resume token
+        with patch('time.strftime', return_value="20101111000000"):
+            self.generate_resume()
+
+        #--test should resume and succeed
+        with OutputIO() as buf:
+            with redirect_stdout(buf):
+                self.assertFalse(ZfsAutobackup("test test_target1 --verbose --test".split(" ")).run())
+
+            print(buf.getvalue())
+            
+            #did we really resume?
+            if "0.6.5" in ZFS_USERSPACE:
+                #abort this late, for beter coverage
+                self.skipTest("Resume not supported in this ZFS userspace version")
+            else:
+                self.assertIn(": resuming", buf.getvalue())
+
+
+        #should resume and succeed
+        with OutputIO() as buf:
+            with redirect_stdout(buf):
+                self.assertFalse(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+            print(buf.getvalue())
+            
+            #did we really resume?
+            if "0.6.5" in ZFS_USERSPACE:
+                #abort this late, for beter coverage
+                self.skipTest("Resume not supported in this ZFS userspace version")
+            else:
+                self.assertIn(": resuming", buf.getvalue())
+
+        r=shelltest("zfs list -H -o name -r -t all test_target1")
+        self.assertMultiLineEqual(r,"""
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+""")
+
+
+    #resume incremental backup
+    def test_incremental_resume(self):
+
+        #initial backup
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty".split(" ")).run())
+
+        #incremental backup leaves resume token
+        with patch('time.strftime', return_value="20101111000001"):
+            self.generate_resume()
+
+        #--test should resume and succeed
+        with OutputIO() as buf:
+            with redirect_stdout(buf):
+                self.assertFalse(ZfsAutobackup("test test_target1 --verbose --test".split(" ")).run())
+
+            print(buf.getvalue())
+            
+            #did we really resume?
+            if "0.6.5" in ZFS_USERSPACE:
+                #abort this late, for beter coverage
+                self.skipTest("Resume not supported in this ZFS userspace version")
+            else:
+                self.assertIn(": resuming", buf.getvalue())
+
+        #should resume and succeed
+        with OutputIO() as buf:
+            with redirect_stdout(buf):
+                self.assertFalse(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+            print(buf.getvalue())
+            
+            #did we really resume?
+            if "0.6.5" in ZFS_USERSPACE:
+                #abort this late, for beter coverage
+                self.skipTest("Resume not supported in this ZFS userspace version")
+            else:
+                self.assertIn(": resuming", buf.getvalue())
+
+        r=shelltest("zfs list -H -o name -r -t all test_target1")
+        self.assertMultiLineEqual(r,"""
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1@test-20101111000001
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+""")
+
+
+    # generate an invalid resume token, and verify if its aborted automaticly
+    def test_initial_resumeabort(self):
+
+        if "0.6.5" in ZFS_USERSPACE:
+            self.skipTest("Resume not supported in this ZFS userspace version")
+
+        #inital backup, leaves resume token
+        with patch('time.strftime', return_value="20101111000000"):
+            self.generate_resume()
+
+        #remove corresponding source snapshot, so it becomes invalid
+        shelltest("zfs destroy test_source1/fs1@test-20101111000000")
+
+        #NOTE: it can only abort the initial dataset if it has no subs
+        shelltest("zfs destroy test_target1/test_source1/fs1/sub; true")
+
+        #--test try again, should abort old resume
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --test".split(" ")).run())
+
+        #try again, should abort old resume
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+        r=shelltest("zfs list -H -o name -r -t all test_target1")
+        self.assertMultiLineEqual(r,"""
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000001
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+""")
+
+
+    # generate an invalid resume token, and verify if its aborted automaticly
+    def test_incremental_resumeabort(self):
+
+        if "0.6.5" in ZFS_USERSPACE:
+            self.skipTest("Resume not supported in this ZFS userspace version")
+
+        #initial backup
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty".split(" ")).run())
+
+        #icremental backup, leaves resume token
+        with patch('time.strftime', return_value="20101111000001"):
+            self.generate_resume()
+
+        #remove corresponding source snapshot, so it becomes invalid
+        shelltest("zfs destroy test_source1/fs1@test-20101111000001")
+
+        #--test try again, should abort old resume
+        with patch('time.strftime', return_value="20101111000002"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --test".split(" ")).run())
+
+        #try again, should abort old resume
+        with patch('time.strftime', return_value="20101111000002"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+        r=shelltest("zfs list -H -o name -r -t all test_target1")
+        self.assertMultiLineEqual(r,"""
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1@test-20101111000002
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+""")
+
+
+    #create a resume situation, where the other side doesnt want the snapshot anymore ( should abort resume )
+    def test_abort_unwanted_resume(self):
+        
+        if "0.6.5" in ZFS_USERSPACE:
+            self.skipTest("Resume not supported in this ZFS userspace version")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+        #generate resume
+        with patch('time.strftime', return_value="20101111000001"):
+            self.generate_resume()
+
+        with OutputIO() as buf:
+            with redirect_stdout(buf):
+                #incremental, doesnt want previous anymore
+                with patch('time.strftime', return_value="20101111000002"):
+                    self.assertFalse(ZfsAutobackup("test test_target1 --verbose --keep-target=0 --debug --allow-empty".split(" ")).run())
+
+            print(buf.getvalue())
+            
+            self.assertIn(": aborting resume, since", buf.getvalue())
+
+        r=shelltest("zfs list -H -o name -r -t all test_target1")
+        self.assertMultiLineEqual(r,"""
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000002
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000002
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000002
+""")
+
+   
+    def test_missing_common(self):
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty".split(" ")).run())
+
+        #remove common snapshot and leave nothing
+        shelltest("zfs release zfs_autobackup:test test_source1/fs1@test-20101111000000")
+        shelltest("zfs destroy test_source1/fs1@test-20101111000000")
+
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertTrue(ZfsAutobackup("test test_target1 --verbose --allow-empty".split(" ")).run())
+
+
+
+
+    ############# TODO:
+    def  test_ignoretransfererrors(self):
+        
+        self.skipTest("todo: create some kind of situation where zfs recv exits with an error but transfer is still ok (happens in practice with acltype)")

test_regressions.py

@@ -0,0 +1,20 @@
+
+from basetest import *
+
+
+class TestZfsNode(unittest2.TestCase):
+
+    def setUp(self):
+        prepare_zpools()
+        self.longMessage=True
+
+    # #resume initial backup
+    # def test_keepsource0(self):
+        
+    #     #somehow only specifying --allow-empty --keep-source 0 failed:
+    #     with patch('time.strftime', return_value="20101111000000"):
+    #         self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty --keep-source 0".split(" ")).run())
+
+    #     with patch('time.strftime', return_value="20101111000001"):
+    #         self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty --keep-source 0".split(" ")).run())
+

test_thinner.py

@@ -0,0 +1,139 @@
+from basetest import *
+
+#randint is different in python 2 vs 3
+randint_compat = lambda lo, hi: lo + int(random.random() * (hi + 1 - lo))
+
+
+class Thing:
+    def __init__(self, timestamp):
+        self.timestamp=timestamp
+
+    def __str__(self):
+        # age=now-self.timestamp
+        struct=time.gmtime(self.timestamp)
+        return("{}".format(time.strftime("%Y-%m-%d %H:%M:%S",struct)))
+
+
+class TestThinner(unittest2.TestCase):
+
+    # def setUp(self):
+
+        # return super().setUp()
+
+    def test_incremental(self):
+        ok=['2023-01-03 10:53:16',
+            '2024-01-02 15:43:29',
+            '2025-01-01 06:15:32',
+            '2026-01-01 02:48:23',
+            '2026-04-07 20:07:36',
+            '2026-05-07 02:30:29',
+            '2026-06-06 01:19:46',
+            '2026-07-06 06:38:09',
+            '2026-08-05 05:08:53',
+            '2026-09-04 03:33:04',
+            '2026-10-04 05:27:09',
+            '2026-11-04 04:01:17',
+            '2026-12-03 13:49:56',
+            '2027-01-01 17:02:00',
+            '2027-01-03 04:26:42',
+            '2027-02-01 14:16:02',
+            '2027-02-12 03:31:02',
+            '2027-02-18 00:33:10',
+            '2027-02-26 21:09:54',
+            '2027-03-02 08:05:18',
+            '2027-03-03 16:46:09',
+            '2027-03-04 06:39:14',
+            '2027-03-06 03:35:41',
+            '2027-03-08 12:24:42',
+            '2027-03-08 20:34:57']
+
+
+
+
+        #some arbitrary date
+        now=1589229252
+        #we want deterministic results
+        random.seed(1337)
+        thinner=Thinner("5,10s1min,1d1w,1w1m,1m12m,1y5y")
+        things=[]
+
+        #thin incrementally while adding
+        for i in range(0,5000):
+
+            #increase random amount of time and maybe add a thing
+            now=now+randint_compat(0,3600*24)
+            if random.random()>=0.5:
+                things.append(Thing(now))
+
+            (keeps, removes)=thinner.thin(things, now=now)
+            things=keeps
+
+
+        result=[]
+        for thing in things:
+            result.append(str(thing))
+        
+        print("Thinner result incremental:")
+        pprint.pprint(result)
+
+        self.assertEqual(result, ok)
+
+
+    def test_full(self):
+        ok=['2022-03-09 01:56:23',
+            '2023-01-03 10:53:16',
+            '2024-01-02 15:43:29',
+            '2025-01-01 06:15:32',
+            '2026-01-01 02:48:23',
+            '2026-03-14 09:08:04',
+            '2026-04-07 20:07:36',
+            '2026-05-07 02:30:29',
+            '2026-06-06 01:19:46',
+            '2026-07-06 06:38:09',
+            '2026-08-05 05:08:53',
+            '2026-09-04 03:33:04',
+            '2026-10-04 05:27:09',
+            '2026-11-04 04:01:17',
+            '2026-12-03 13:49:56',
+            '2027-01-01 17:02:00',
+            '2027-01-03 04:26:42',
+            '2027-02-01 14:16:02',
+            '2027-02-08 02:41:14',
+            '2027-02-12 03:31:02',
+            '2027-02-18 00:33:10',
+            '2027-02-26 21:09:54',
+            '2027-03-02 08:05:18',
+            '2027-03-03 16:46:09',
+            '2027-03-04 06:39:14',
+            '2027-03-06 03:35:41',
+            '2027-03-08 12:24:42',
+            '2027-03-08 20:34:57']
+
+        #some arbitrary date
+        now=1589229252
+        #we want deterministic results
+        random.seed(1337)
+        thinner=Thinner("5,10s1min,1d1w,1w1m,1m12m,1y5y")
+        things=[]
+
+        for i in range(0,5000):
+
+            #increase random amount of time and maybe add a thing
+            now=now+randint_compat(0,3600*24)
+            if random.random()>=0.5:
+                things.append(Thing(now))
+
+        (things, removes)=thinner.thin(things, now=now)
+
+        result=[]
+        for thing in things:
+            result.append(str(thing))
+        
+        print("Thinner result full:")
+        pprint.pprint(result)
+
+        self.assertEqual(result, ok)
+
+
+if __name__ == '__main__':
+    unittest.main()

test_zfsautobackup.py

@@ -0,0 +1,847 @@
+from basetest import *
+import time
+
+
+
+class TestZfsAutobackup(unittest2.TestCase):
+    
+    def setUp(self):
+        prepare_zpools()
+        self.longMessage=True
+
+    def test_invalidpars(self):
+
+        self.assertEqual(ZfsAutobackup("test test_target1 --keep-source -1".split(" ")).run(), 255)
+
+    def  test_snapshotmode(self):
+        """test snapshot tool mode"""
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --allow-empty --verbose".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000002"):
+            self.assertFalse(ZfsAutobackup("test --verbose --allow-empty --keep-source 0".split(" ")).run())
+
+        #on source: only has 1 and 2 (1 was hold)
+        #on target: has 0 and 1  
+        #XXX:
+        r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+        self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-20101111000001
+test_source1/fs1@test-20101111000002
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000001
+test_source1/fs1/sub@test-20101111000002
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000001
+test_source2/fs2/sub@test-20101111000002
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1@test-20101111000001
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source1/fs1/sub@test-20101111000001
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+test_target1/test_source2/fs2/sub@test-20101111000001
+""")
+
+
+
+    def  test_defaults(self):
+
+        with self.subTest("no datasets selected"):
+            with OutputIO() as buf:
+                with redirect_stderr(buf):
+                    with patch('time.strftime', return_value="20101111000000"):
+                        self.assertTrue(ZfsAutobackup("nonexisting test_target1 --verbose --debug".split(" ")).run())
+
+                print(buf.getvalue())
+                #correct message?
+                self.assertIn("No source filesystems selected", buf.getvalue())
+
+
+        with self.subTest("defaults with full verbose and debug"):
+
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup("test test_target1 --verbose --debug".split(" ")).run())
+
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-20101111000000
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000000
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+""")
+
+        with self.subTest("bare defaults, allow empty"):
+            with patch('time.strftime', return_value="20101111000001"):
+                self.assertFalse(ZfsAutobackup("test test_target1 --allow-empty".split(" ")).run())
+
+        
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-20101111000000
+test_source1/fs1@test-20101111000001
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+test_source1/fs1/sub@test-20101111000001
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000000
+test_source2/fs2/sub@test-20101111000001
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1@test-20101111000001
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source1/fs1/sub@test-20101111000001
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+test_target1/test_source2/fs2/sub@test-20101111000001
+""")
+
+        with self.subTest("verify holds"):
+
+            r=shelltest("zfs get -r userrefs test_source1 test_source2 test_target1")
+            self.assertMultiLineEqual(r,"""
+NAME                                                   PROPERTY  VALUE     SOURCE
+test_source1                                           userrefs  -         -
+test_source1/fs1                                       userrefs  -         -
+test_source1/fs1@test-20101111000000                   userrefs  0         -
+test_source1/fs1@test-20101111000001                   userrefs  1         -
+test_source1/fs1/sub                                   userrefs  -         -
+test_source1/fs1/sub@test-20101111000000               userrefs  0         -
+test_source1/fs1/sub@test-20101111000001               userrefs  1         -
+test_source2                                           userrefs  -         -
+test_source2/fs2                                       userrefs  -         -
+test_source2/fs2/sub                                   userrefs  -         -
+test_source2/fs2/sub@test-20101111000000               userrefs  0         -
+test_source2/fs2/sub@test-20101111000001               userrefs  1         -
+test_source2/fs3                                       userrefs  -         -
+test_source2/fs3/sub                                   userrefs  -         -
+test_target1                                           userrefs  -         -
+test_target1/test_source1                              userrefs  -         -
+test_target1/test_source1/fs1                          userrefs  -         -
+test_target1/test_source1/fs1@test-20101111000000      userrefs  0         -
+test_target1/test_source1/fs1@test-20101111000001      userrefs  1         -
+test_target1/test_source1/fs1/sub                      userrefs  -         -
+test_target1/test_source1/fs1/sub@test-20101111000000  userrefs  0         -
+test_target1/test_source1/fs1/sub@test-20101111000001  userrefs  1         -
+test_target1/test_source2                              userrefs  -         -
+test_target1/test_source2/fs2                          userrefs  -         -
+test_target1/test_source2/fs2/sub                      userrefs  -         -
+test_target1/test_source2/fs2/sub@test-20101111000000  userrefs  0         -
+test_target1/test_source2/fs2/sub@test-20101111000001  userrefs  1         -
+""")
+
+        #make sure time handling is correctly. try to make snapshots a year appart and verify that only snapshots mostly 1y old are kept
+        with self.subTest("test time checking"):
+            with patch('time.strftime', return_value="20111111000000"):
+                self.assertFalse(ZfsAutobackup("test test_target1 --allow-empty --verbose".split(" ")).run())
+
+
+            time_str="20111112000000" #month in the "future"
+            future_timestamp=time_secs=time.mktime(time.strptime(time_str,"%Y%m%d%H%M%S"))
+            with patch('time.time', return_value=future_timestamp):
+                with patch('time.strftime', return_value="20111111000001"):
+                    self.assertFalse(ZfsAutobackup("test test_target1 --allow-empty --verbose --keep-source 1y1y --keep-target 1d1y".split(" ")).run())
+
+
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-20111111000000
+test_source1/fs1@test-20111111000001
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20111111000000
+test_source1/fs1/sub@test-20111111000001
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20111111000000
+test_source2/fs2/sub@test-20111111000001
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20111111000000
+test_target1/test_source1/fs1@test-20111111000001
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20111111000000
+test_target1/test_source1/fs1/sub@test-20111111000001
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20111111000000
+test_target1/test_source2/fs2/sub@test-20111111000001
+""")
+
+
+    def  test_ignore_othersnaphots(self):
+
+        r=shelltest("zfs snapshot test_source1/fs1@othersimple")
+        r=shelltest("zfs snapshot test_source1/fs1@otherdate-20001111000000")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@othersimple
+test_source1/fs1@otherdate-20001111000000
+test_source1/fs1@test-20101111000000
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000000
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+""")
+
+    def  test_othersnaphots(self):
+
+        r=shelltest("zfs snapshot test_source1/fs1@othersimple")
+        r=shelltest("zfs snapshot test_source1/fs1@otherdate-20001111000000")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --other-snapshots".split(" ")).run())
+
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@othersimple
+test_source1/fs1@otherdate-20001111000000
+test_source1/fs1@test-20101111000000
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000000
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@othersimple
+test_target1/test_source1/fs1@otherdate-20001111000000
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+""")
+
+
+    def  test_nosnapshot(self):
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-snapshot".split(" ")).run())
+
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            #(only parents are created )
+            #TODO: it probably shouldn't create these
+            self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1/sub
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source2
+test_target1/test_source2/fs2
+""")
+
+
+    def  test_nosend(self):
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-send".split(" ")).run())
+
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            #(only parents are created )
+            #TODO: it probably shouldn't create these
+            self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-20101111000000
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000000
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+""")
+
+
+    def  test_ignorereplicated(self):
+        r=shelltest("zfs snapshot test_source1/fs1@otherreplication")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --ignore-replicated".split(" ")).run())
+
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            #(only parents are created )
+            #TODO: it probably shouldn't create these
+            self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@otherreplication
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000000
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+""")
+
+    def  test_noholds(self):
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-holds".split(" ")).run())
+
+            r=shelltest("zfs get -r userrefs test_source1 test_source2 test_target1")
+            self.assertMultiLineEqual(r,"""
+NAME                                                   PROPERTY  VALUE     SOURCE
+test_source1                                           userrefs  -         -
+test_source1/fs1                                       userrefs  -         -
+test_source1/fs1@test-20101111000000                   userrefs  0         -
+test_source1/fs1/sub                                   userrefs  -         -
+test_source1/fs1/sub@test-20101111000000               userrefs  0         -
+test_source2                                           userrefs  -         -
+test_source2/fs2                                       userrefs  -         -
+test_source2/fs2/sub                                   userrefs  -         -
+test_source2/fs2/sub@test-20101111000000               userrefs  0         -
+test_source2/fs3                                       userrefs  -         -
+test_source2/fs3/sub                                   userrefs  -         -
+test_target1                                           userrefs  -         -
+test_target1/test_source1                              userrefs  -         -
+test_target1/test_source1/fs1                          userrefs  -         -
+test_target1/test_source1/fs1@test-20101111000000      userrefs  1         -
+test_target1/test_source1/fs1/sub                      userrefs  -         -
+test_target1/test_source1/fs1/sub@test-20101111000000  userrefs  1         -
+test_target1/test_source2                              userrefs  -         -
+test_target1/test_source2/fs2                          userrefs  -         -
+test_target1/test_source2/fs2/sub                      userrefs  -         -
+test_target1/test_source2/fs2/sub@test-20101111000000  userrefs  1         -
+""")
+
+
+    def  test_strippath(self):
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --strip-path=1".split(" ")).run())
+
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-20101111000000
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000000
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/fs1
+test_target1/fs1@test-20101111000000
+test_target1/fs1/sub
+test_target1/fs1/sub@test-20101111000000
+test_target1/fs2
+test_target1/fs2/sub
+test_target1/fs2/sub@test-20101111000000
+""")
+
+
+    def  test_clearrefres(self):
+
+        #on zfs utils 0.6.x -x isnt supported 
+        r=shelltest("zfs recv -x bla test >/dev/null </dev/zero; echo $?")
+        if r=="\n2\n":
+            self.skipTest("This zfs-userspace version doesnt support -x")
+
+        r=shelltest("zfs set refreservation=1M test_source1/fs1")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --clear-refreservation".split(" ")).run())
+
+            r=shelltest("zfs get refreservation -r test_source1 test_source2 test_target1")
+            self.assertMultiLineEqual(r,"""
+NAME                                                   PROPERTY        VALUE      SOURCE
+test_source1                                           refreservation  none       default
+test_source1/fs1                                       refreservation  1M         local
+test_source1/fs1@test-20101111000000                   refreservation  -          -
+test_source1/fs1/sub                                   refreservation  none       default
+test_source1/fs1/sub@test-20101111000000               refreservation  -          -
+test_source2                                           refreservation  none       default
+test_source2/fs2                                       refreservation  none       default
+test_source2/fs2/sub                                   refreservation  none       default
+test_source2/fs2/sub@test-20101111000000               refreservation  -          -
+test_source2/fs3                                       refreservation  none       default
+test_source2/fs3/sub                                   refreservation  none       default
+test_target1                                           refreservation  none       default
+test_target1/test_source1                              refreservation  none       default
+test_target1/test_source1/fs1                          refreservation  none       default
+test_target1/test_source1/fs1@test-20101111000000      refreservation  -          -
+test_target1/test_source1/fs1/sub                      refreservation  none       default
+test_target1/test_source1/fs1/sub@test-20101111000000  refreservation  -          -
+test_target1/test_source2                              refreservation  none       default
+test_target1/test_source2/fs2                          refreservation  none       default
+test_target1/test_source2/fs2/sub                      refreservation  none       default
+test_target1/test_source2/fs2/sub@test-20101111000000  refreservation  -          -
+""")
+
+
+    def  test_clearmount(self):
+
+        #on zfs utils 0.6.x -o isnt supported 
+        r=shelltest("zfs recv -o bla=1 test >/dev/null </dev/zero; echo $?")
+        if r=="\n2\n":
+            self.skipTest("This zfs-userspace version doesnt support -o")
+
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --clear-mountpoint".split(" ")).run())
+
+            r=shelltest("zfs get canmount -r test_source1 test_source2 test_target1")
+            self.assertMultiLineEqual(r,"""
+NAME                                                   PROPERTY  VALUE     SOURCE
+test_source1                                           canmount  on        default
+test_source1/fs1                                       canmount  on        default
+test_source1/fs1@test-20101111000000                   canmount  -         -
+test_source1/fs1/sub                                   canmount  on        default
+test_source1/fs1/sub@test-20101111000000               canmount  -         -
+test_source2                                           canmount  on        default
+test_source2/fs2                                       canmount  on        default
+test_source2/fs2/sub                                   canmount  on        default
+test_source2/fs2/sub@test-20101111000000               canmount  -         -
+test_source2/fs3                                       canmount  on        default
+test_source2/fs3/sub                                   canmount  on        default
+test_target1                                           canmount  on        default
+test_target1/test_source1                              canmount  on        default
+test_target1/test_source1/fs1                          canmount  noauto    local
+test_target1/test_source1/fs1@test-20101111000000      canmount  -         -
+test_target1/test_source1/fs1/sub                      canmount  noauto    local
+test_target1/test_source1/fs1/sub@test-20101111000000  canmount  -         -
+test_target1/test_source2                              canmount  on        default
+test_target1/test_source2/fs2                          canmount  on        default
+test_target1/test_source2/fs2/sub                      canmount  noauto    local
+test_target1/test_source2/fs2/sub@test-20101111000000  canmount  -         -
+""")
+
+
+    def  test_rollback(self):
+
+        #initial backup
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+        #make change
+        r=shelltest("zfs mount test_target1/test_source1/fs1")
+        r=shelltest("touch /test_target1/test_source1/fs1/change.txt")
+
+        with patch('time.strftime', return_value="20101111000001"):
+            #should fail (busy)
+            self.assertTrue(ZfsAutobackup("test test_target1 --verbose --allow-empty".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000002"):
+            #rollback, should succeed
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty --rollback".split(" ")).run())
+
+
+    def  test_destroyincompat(self):
+
+        #initial backup
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+        #add multiple compatible snapshot (written is still 0)
+        r=shelltest("zfs snapshot test_target1/test_source1/fs1@compatible1")
+        r=shelltest("zfs snapshot test_target1/test_source1/fs1@compatible2")
+
+        with patch('time.strftime', return_value="20101111000001"):
+            #should be ok, is compatible
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty".split(" ")).run())
+
+        #add incompatible snapshot by changing and snapshotting
+        r=shelltest("zfs mount test_target1/test_source1/fs1")
+        r=shelltest("touch /test_target1/test_source1/fs1/change.txt")
+        r=shelltest("zfs snapshot test_target1/test_source1/fs1@incompatible1")
+
+
+        with patch('time.strftime', return_value="20101111000002"):
+            #--test should fail, now incompatible
+            self.assertTrue(ZfsAutobackup("test test_target1 --verbose --allow-empty --test".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000002"):
+            #should fail, now incompatible
+            self.assertTrue(ZfsAutobackup("test test_target1 --verbose --allow-empty".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000003"):
+            #--test should succeed by destroying incompatibles
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty --destroy-incompatible --test".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000003"):
+            #should succeed by destroying incompatibles
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty --destroy-incompatible".split(" ")).run())
+
+
+
+
+
+    def test_keepsourcetarget(self):
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty".split(" ")).run())
+
+        #should still have all snapshots
+        r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+        self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-20101111000000
+test_source1/fs1@test-20101111000001
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+test_source1/fs1/sub@test-20101111000001
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000000
+test_source2/fs2/sub@test-20101111000001
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1@test-20101111000001
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source1/fs1/sub@test-20101111000001
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+test_target1/test_source2/fs2/sub@test-20101111000001
+""")
+
+
+        #run again with keep=0
+        with patch('time.strftime', return_value="20101111000002"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty --keep-source=0 --keep-target=0".split(" ")).run())
+
+        #should only have last snapshots
+        r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+        self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-20101111000002
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000002
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000002
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000002
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000002
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000002
+""")
+
+
+    def test_ssh(self):
+
+        #test all ssh directions
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty --ssh-source localhost".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty --ssh-target localhost".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000002"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty --ssh-source localhost --ssh-target localhost".split(" ")).run())
+
+
+        r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+        self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-20101111000000
+test_source1/fs1@test-20101111000001
+test_source1/fs1@test-20101111000002
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+test_source1/fs1/sub@test-20101111000001
+test_source1/fs1/sub@test-20101111000002
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000000
+test_source2/fs2/sub@test-20101111000001
+test_source2/fs2/sub@test-20101111000002
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1@test-20101111000001
+test_target1/test_source1/fs1@test-20101111000002
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source1/fs1/sub@test-20101111000001
+test_target1/test_source1/fs1/sub@test-20101111000002
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+test_target1/test_source2/fs2/sub@test-20101111000001
+test_target1/test_source2/fs2/sub@test-20101111000002
+""")
+
+
+    def  test_minchange(self):
+
+        #initial
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --min-change 100000".split(" ")).run())
+
+        #make small change, use umount to reflect the changes immediately
+        r=shelltest("zfs set compress=off test_source1")
+        r=shelltest("touch /test_source1/fs1/change.txt")
+        r=shelltest("zfs umount test_source1/fs1; zfs mount test_source1/fs1")
+        
+
+        #too small change, takes no snapshots
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --min-change 100000".split(" ")).run())
+
+        #make big change
+        r=shelltest("dd if=/dev/zero of=/test_source1/fs1/change.txt bs=200000 count=1")
+        r=shelltest("zfs umount test_source1/fs1; zfs mount test_source1/fs1")
+
+        #bigger change, should take snapshot
+        with patch('time.strftime', return_value="20101111000002"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --min-change 100000".split(" ")).run())
+
+        r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+        self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-20101111000000
+test_source1/fs1@test-20101111000002
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000000
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1@test-20101111000002
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+""")
+
+    def  test_test(self):
+
+        #initial
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --test".split(" ")).run())
+
+        r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+        self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1/sub
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+""")
+
+        #actual make initial backup
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+
+        #test incremental
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --test".split(" ")).run())
+
+        r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+        self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-20101111000001
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000001
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000001
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000001
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000001
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000001
+""")
+
+
+    def test_migrate(self):
+        """test migration from other snapshotting systems. zfs-autobackup should be able to continue from any common snapshot, not just its own."""
+
+        shelltest("zfs snapshot test_source1/fs1@migrate1")
+        shelltest("zfs create test_target1/test_source1")
+        shelltest("zfs send  test_source1/fs1@migrate1| zfs recv test_target1/test_source1/fs1")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose".split(" ")).run())
+
+        r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+        self.assertMultiLineEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@migrate1
+test_source1/fs1@test-20101111000000
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000000
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@migrate1
+test_target1/test_source1/fs1@test-20101111000000
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000000
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000000
+""")
+
+
+###########################
+# TODO:
+
+    def  test_raw(self):
+        
+        self.skipTest("todo: later when travis supports zfs 0.8")
+
+
+

test_zfsnode.py

@@ -0,0 +1,123 @@
+from basetest import *
+
+
+class TestZfsNode(unittest2.TestCase):
+
+    def setUp(self):
+        prepare_zpools()
+        # return super().setUp()
+
+
+    def test_consistent_snapshot(self):
+        logger=Logger()
+        description="[Source]"
+        node=ZfsNode("test", logger, description=description)
+
+        with self.subTest("first snapshot"):
+            node.consistent_snapshot(node.selected_datasets, "test-1",100000)
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            self.assertEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-1
+test_source1/fs1/sub
+test_source1/fs1/sub@test-1
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-1
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+""")
+
+
+        with self.subTest("second snapshot, no changes, no snapshot"):
+            node.consistent_snapshot(node.selected_datasets, "test-2",1)
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            self.assertEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-1
+test_source1/fs1/sub
+test_source1/fs1/sub@test-1
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-1
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+""")
+
+        with self.subTest("second snapshot, no changes, empty snapshot"):
+            node.consistent_snapshot(node.selected_datasets, "test-2",0)
+            r=shelltest("zfs list -H -o name -r -t all "+TEST_POOLS)
+            self.assertEqual(r,"""
+test_source1
+test_source1/fs1
+test_source1/fs1@test-1
+test_source1/fs1@test-2
+test_source1/fs1/sub
+test_source1/fs1/sub@test-1
+test_source1/fs1/sub@test-2
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-1
+test_source2/fs2/sub@test-2
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+""")
+
+
+    def test_getselected(self):
+        logger=Logger()
+        description="[Source]"
+        node=ZfsNode("test", logger, description=description)
+        s=pformat(node.selected_datasets)
+        print(s)
+
+        #basics
+        self.assertEqual (s, """[(local): test_source1/fs1,
+ (local): test_source1/fs1/sub,
+ (local): test_source2/fs2/sub]""")
+
+        #caching, so expect same result after changing it
+        subprocess.check_call("zfs set autobackup:test=true test_source2/fs3", shell=True)
+        self.assertEqual (s, """[(local): test_source1/fs1,
+ (local): test_source1/fs1/sub,
+ (local): test_source2/fs2/sub]""")
+
+
+    def test_validcommand(self):
+        logger=Logger()
+        description="[Source]"
+        node=ZfsNode("test", logger, description=description)
+
+
+        with self.subTest("test invalid option"):
+            self.assertFalse(node.valid_command(["zfs", "send", "--invalid-option", "nonexisting"]))
+        with self.subTest("test valid option"):
+            self.assertTrue(node.valid_command(["zfs", "send", "-v", "nonexisting"]))
+
+    def test_supportedsendoptions(self):
+        logger=Logger()
+        description="[Source]"
+        node=ZfsNode("test", logger, description=description)
+        # -D propably always supported
+        self.assertGreater(len(node.supported_send_options),0)
+    
+
+    def test_supportedrecvoptions(self):
+        logger=Logger()
+        description="[Source]"
+        #NOTE: this couldnt hang via ssh if we dont close filehandles properly. (which was a previous bug)
+        node=ZfsNode("test", logger, description=description, ssh_to='localhost')
+        self.assertIsInstance(node.supported_recv_options, list)
+        
+
+
+if __name__ == '__main__':
+    unittest.main()

zfs_autobackup

@@ -1,741 +0,0 @@
-#!/usr/bin/env python2
-# -*- coding: utf8 -*-
-from __future__ import print_function
-import os
-import sys
-import re
-import traceback
-import subprocess
-import pprint
-import time
-
-
-def error(txt):
-    print(txt, file=sys.stderr)
-
-
-
-def verbose(txt):
-    if args.verbose:
-        print(txt)
-
-
-
-def debug(txt):
-    if args.debug:
-        print(txt)
-
-
-"""run a command. specifiy ssh user@host to run remotely"""
-def run(cmd, input=None, ssh_to="local", tab_split=False, valid_exitcodes=[ 0 ], test=False):
-
-    encoded_cmd=[]
-
-
-    #use ssh?
-    if ssh_to != "local":
-        encoded_cmd.extend(["ssh", ssh_to])
-
-
-        #make sure the command gets all the data in utf8 format:
-        #(this is neccesary if LC_ALL=en_US.utf8 is not set in the environment)
-        for arg in cmd:
-            #add single quotes for remote commands to support spaces and other wierd stuff (remote commands are executed in a shell)
-            encoded_cmd.append( ("'"+arg+"'").encode('utf-8'))
-
-    else:
-        for arg in cmd:
-            encoded_cmd.append(arg.encode('utf-8'))
-
-
-    #the accurate way of displaying it whould be: print encoded_cmd
-    #However, we use the more human-readable way, but this is not always properly escaped!
-    #(most of the time it should be copypastable however.)
-    debug_txt="# "+" ".join(encoded_cmd)
-
-    if test:
-        debug("[TEST] "+debug_txt)
-    else:
-        debug(debug_txt)
-
-    if input:
-        debug("INPUT:\n"+input.rstrip())
-        stdin=subprocess.PIPE
-    else:
-        stdin=None
-
-    if test:
-        return
-
-    p=subprocess.Popen(encoded_cmd, env=os.environ, stdout=subprocess.PIPE, stdin=stdin)
-    output=p.communicate(input=input)[0]
-    if p.returncode not in valid_exitcodes:
-        raise(subprocess.CalledProcessError(p.returncode, encoded_cmd))
-
-    lines=output.splitlines()
-    if not tab_split:
-        return(lines)
-    else:
-        ret=[]
-        for line in lines:
-            ret.append(line.split("\t"))
-        return(ret)
-
-
-"""determine filesystems that should be backupped by looking at the special autobackup-property"""
-def zfs_get_selected_filesystems(ssh_to, backup_name):
-    #get all source filesystems that have the backup property
-    source_filesystems=run(ssh_to=ssh_to, tab_split=True, cmd=[
-        "zfs", "get", "-t",  "volume,filesystem", "-o", "name,value,source", "-s", "local,inherited", "-H", "autobackup:"+backup_name
-    ])
-
-    #determine filesystems that should be actually backupped
-    selected_filesystems=[]
-    direct_filesystems=[]
-    for source_filesystem in source_filesystems:
-        (name,value,source)=source_filesystem
-        if value=="false":
-            verbose("Ignored : {0} (disabled)".format(name))
-
-        else:
-            if source=="local" and ( value=="true" or value=="child"):
-                direct_filesystems.append(name)
-
-            if source=="local" and value=="true":
-                selected_filesystems.append(name)
-                verbose("Selected: {0} (direct selection)".format(name))
-            elif source.find("inherited from ")==0 and (value=="true" or value=="child"):
-                inherited_from=re.sub("^inherited from ", "", source)
-                if inherited_from in direct_filesystems:
-                    selected_filesystems.append(name)
-                    verbose("Selected: {0} (inherited selection)".format(name))
-                else:
-                    verbose("Ignored : {0} (already a backup)".format(name))
-            else:
-                verbose("Ignored : {0} (only childs)".format(name))
-
-    return(selected_filesystems)
-
-
-"""determine filesystems that can be resumed via receive_resume_token"""
-def zfs_get_resumable_filesystems(ssh_to, filesystems):
-
-    cmd=[ "zfs", "get", "-t",  "volume,filesystem", "-o", "name,value", "-H", "receive_resume_token" ]
-    cmd.extend(filesystems)
-
-    #TODO: get rid of ugly errors for non-existing target filesystems
-    resumable_filesystems=run(ssh_to=ssh_to, tab_split=True, cmd=cmd, valid_exitcodes= [ 0,1 ] )
-
-    ret={}
-
-    for (resumable_filesystem,token) in resumable_filesystems:
-        if token!='-':
-            ret[resumable_filesystem]=token
-
-    return(ret)
-
-
-"""deferred destroy list of snapshots (in @format). """
-def zfs_destroy_snapshots(ssh_to, snapshots):
-
-    #zfs can only destroy one filesystem at once so we use xargs and stdin
-    run(ssh_to=ssh_to, test=args.test, input="\0".join(snapshots), cmd=
-        [ "xargs", "-0", "-n", "1", "zfs", "destroy", "-d" ]
-    )
-
-"""destroy list of filesystems """
-def zfs_destroy(ssh_to, filesystems, recursive=False):
-
-    cmd=[ "xargs", "-0", "-n", "1", "zfs", "destroy" ]
-
-    if recursive:
-        cmd.append("-r")
-
-    #zfs can only destroy one filesystem at once so we use xargs and stdin
-    run(ssh_to=ssh_to, test=args.test, input="\0".join(filesystems), cmd=cmd)
-
-#simulate snapshots for --test option
-test_snapshots={}
-
-
-
-"""create snapshot on multiple filesystems at once (atomicly per pool)"""
-def zfs_create_snapshot(ssh_to, filesystems, snapshot):
-
-
-    #collect per pool, zfs can only take atomic snapshots per pool
-    pools={}
-    for filesystem in filesystems:
-        pool=filesystem.split('/')[0]
-        if pool not in pools:
-            pools[pool]=[]
-        pools[pool].append(filesystem)
-
-    for pool in pools:
-        cmd=[ "zfs", "snapshot" ]
-        for filesystem in pools[pool]:
-            cmd.append(filesystem+"@"+snapshot)
-
-            #in testmode we dont actually make changes, so keep them in a list to simulate
-            if args.test:
-                if not ssh_to in test_snapshots:
-                    test_snapshots[ssh_to]={}
-                if not filesystem in test_snapshots[ssh_to]:
-                    test_snapshots[ssh_to][filesystem]=[]
-                test_snapshots[ssh_to][filesystem].append(snapshot)
-
-        run(ssh_to=ssh_to, tab_split=False, cmd=cmd, test=args.test)
-
-
-"""get names of all snapshots for specified filesystems belonging to backup_name
-
-return[filesystem_name]=[ "snashot1", "snapshot2", ... ]
-"""
-def zfs_get_snapshots(ssh_to, filesystems, backup_name):
-
-    ret={}
-
-    if filesystems:
-        #TODO: get rid of ugly errors for non-existing target filesystems
-        cmd=[
-            "zfs", "list", "-d", "1", "-r", "-t" ,"snapshot", "-H", "-o", "name"
-        ]
-        cmd.extend(filesystems)
-
-        snapshots=run(ssh_to=ssh_to, tab_split=False, cmd=cmd, valid_exitcodes=[ 0,1 ])
-
-
-        for snapshot in snapshots:
-            (filesystem, snapshot_name)=snapshot.split("@")
-            if re.match("^"+backup_name+"-[0-9]*$", snapshot_name):
-                if not filesystem in ret:
-                    ret[filesystem]=[]
-                ret[filesystem].append(snapshot_name)
-
-        #also add any test-snapshots that where created with --test mode
-        if args.test:
-            if ssh_to in test_snapshots:
-                for filesystem in filesystems:
-                    if filesystem in test_snapshots[ssh_to]:
-                        if not filesystem in ret:
-                            ret[filesystem]=[]
-                        ret[filesystem].extend(test_snapshots[ssh_to][filesystem])
-
-    return(ret)
-
-
-def default_tag():
-    return("zfs_autobackup:"+args.backup_name)
-
-"""hold a snapshot so it cant be destroyed accidently by admin or other processes"""
-def zfs_hold_snapshot(ssh_to, snapshot, tag=None):
-    cmd=[
-        "zfs", "hold", tag or default_tag(), snapshot
-    ]
-
-    run(ssh_to=ssh_to, test=args.test, tab_split=False, cmd=cmd, valid_exitcodes=[ 0, 1 ])
-
-
-"""release a snapshot"""
-def zfs_release_snapshot(ssh_to, snapshot, tag=None):
-    cmd=[
-        "zfs", "release", tag or default_tag(), snapshot
-    ]
-
-    run(ssh_to=ssh_to, test=args.test, tab_split=False, cmd=cmd, valid_exitcodes=[ 0, 1 ])
-
-
-
-"""transfer a zfs snapshot from source to target. both can be either local or via ssh.
-
-
-TODO:
-
-(parially implemented, local buffer is a bit more annoying to do)
-
-buffering: specify buffer_size to use mbuffer (or alike) to apply buffering where neccesary
-
-local to local:
-local send -> local buffer -> local receive
-
-local to remote and remote to local:
-local send -> local buffer -> ssh -> remote buffer -> remote receive
-remote send -> remote buffer -> ssh -> local buffer -> local receive
-
-remote to remote:
-remote send -> remote buffer -> ssh -> local buffer -> ssh -> remote buffer -> remote receive
-
-
-
-
-"""
-def zfs_transfer(ssh_source, source_filesystem, first_snapshot, second_snapshot,
-                 ssh_target, target_filesystem, resume_token=None, buffer_size=None):
-
-    #### build source command
-    source_cmd=[]
-
-    if ssh_source != "local":
-        source_cmd.extend([ "ssh", ssh_source ])
-
-    source_cmd.extend(["zfs", "send",  ])
-
-    #all kind of performance options:
-    source_cmd.append("-L") # large block support
-    source_cmd.append("-e") # WRITE_EMBEDDED, more compact stream
-    source_cmd.append("-c") # use compressed WRITE records
-    if not args.resume:
-        source_cmd.append("-D") # dedupped stream, sends less duplicate data
-
-
-
-    #only verbose in debug mode, lots of output
-    if args.debug :
-        source_cmd.append("-v")
-
-
-    if not first_snapshot:
-        txt="Initial transfer of "+source_filesystem+" snapshot "+second_snapshot
-    else:
-        txt="Incremental transfer of "+source_filesystem+" between snapshots "+first_snapshot+"..."+second_snapshot
-
-    if resume_token:
-        source_cmd.extend([ "-t", resume_token ])
-        verbose("RESUMING "+txt)
-
-    else:
-        source_cmd.append("-p")
-
-        if first_snapshot:
-            source_cmd.extend([ "-i", first_snapshot ])
-
-        if ssh_source != "local":
-            source_cmd.append("'" + source_filesystem + "@" + second_snapshot + "'")
-        else:
-            source_cmd.append(source_filesystem + "@" + second_snapshot)
-
-        verbose(txt)
-
-    if args.buffer and args.ssh_source!="local":
-        source_cmd.append("|mbuffer -m {}".format(args.buffer))
-
-
-    #### build target command
-    target_cmd=[]
-
-    if ssh_target != "local":
-        target_cmd.extend([ "ssh", ssh_target ])
-
-    target_cmd.extend(["zfs", "recv", "-u" ])
-
-    # filter certain properties on receive (usefull for linux->freebsd in some cases)
-    if args.filter_properties:
-        for filter_property in args.filter_properties:
-            target_cmd.extend([ "-x" , filter_property ])
-
-    #also verbose in --verbose mode so we can see the transfer speed when its completed
-    if args.verbose or args.debug:
-        target_cmd.append("-v")
-
-    if args.resume:
-        target_cmd.append("-s")
-
-
-    if ssh_target!="local":
-        target_cmd.append("'" + target_filesystem + "'")
-    else:
-        target_cmd.append(target_filesystem)
-
-    if args.buffer and  args.ssh_target!="local":
-        target_cmd.append("|mbuffer -m {}".format(args.buffer))
-
-
-    #### make sure parent on target exists
-    parent_filesystem= "/".join(target_filesystem.split("/")[:-1])
-    run(ssh_to=ssh_target, cmd=[ "zfs", "create" ,"-p", parent_filesystem ], test=args.test)
-
-    ### execute pipe
-    debug_txt="# "+source_cmd[0]+" '"+("' '".join(source_cmd[1:]))+"'" + " | " + target_cmd[0]+" '"+("' '".join(target_cmd[1:]))+"'"
-
-    if args.test:
-        debug("[TEST] "+debug_txt)
-        return
-    else:
-        debug(debug_txt)
-
-    source_proc=subprocess.Popen(source_cmd, env=os.environ, stdout=subprocess.PIPE)
-    target_proc=subprocess.Popen(target_cmd, env=os.environ, stdin=source_proc.stdout)
-    source_proc.stdout.close() # Allow p1 to receive a SIGPIPE if p2 exits.
-    target_proc.communicate()
-
-    if not args.ignore_transfer_errors:
-        if source_proc.returncode:
-            raise(subprocess.CalledProcessError(source_proc.returncode, source_cmd))
-
-        #zfs recv sometimes gives an exitcode 1 while the transfer was succesfull, therefore we ignore exit 1's and do an extra check to see if the snapshot is there.
-        if target_proc.returncode and target_proc.returncode!=1:
-            raise(subprocess.CalledProcessError(target_proc.returncode, target_cmd))
-
-    debug("Verifying if snapshot exists on target")
-    run(ssh_to=ssh_target, cmd=["zfs", "list", target_filesystem+"@"+second_snapshot ])
-
-
-
-"""get filesystems that where already backupped to a target. """
-def zfs_get_backupped_filesystems(ssh_to, backup_name, target_fs):
-    #get all target filesystems that have received or inherited the backup propert, under the target_fs tree
-    ret=run(ssh_to=ssh_to, tab_split=False, cmd=[
-        "zfs", "get", "-r", "-t",  "volume,filesystem", "-o", "name", "-s", "received,inherited", "-H", "autobackup:"+backup_name, target_fs
-    ])
-
-    return(ret)
-
-
-
-"""get filesystems that where once backupped to target but are no longer selected on source
-
-these are filesystems that are not in the list in target_filesystems.
-
-this happens when filesystems are destroyed or unselected on the source.
-"""
-def get_stale_backupped_filesystems(ssh_to, backup_name, target_fs, target_filesystems):
-
-    backupped_filesystems=zfs_get_backupped_filesystems(ssh_to=ssh_to, backup_name=backup_name, target_fs=target_fs)
-
-    #determine backupped filesystems that are not in target_filesystems anymore
-    stale_backupped_filesystems=[]
-    for backupped_filesystem in backupped_filesystems:
-        if backupped_filesystem not in target_filesystems:
-            stale_backupped_filesystems.append(backupped_filesystem)
-
-    return(stale_backupped_filesystems)
-
-
-now=time.time()
-"""determine list of snapshot (in @format) to destroy, according to age"""
-def determine_destroy_list(snapshots, days):
-    ret=[]
-    for filesystem in snapshots:
-        for snapshot in snapshots[filesystem]:
-            time_str=re.findall("^.*-([0-9]*)$", snapshot)[0]
-            if len(time_str)==14:
-                #new format:
-                time_secs=time.mktime(time.strptime(time_str,"%Y%m%d%H%M%S"))
-            else:
-                time_secs=int(time_str)
-                # verbose("time_secs"+time_str)
-            if (now-time_secs) > (24 * 3600 * days):
-                ret.append(filesystem+"@"+snapshot)
-
-    return(ret)
-
-
-def lstrip_path(path, count):
-    return("/".join(path.split("/")[count:]))
-
-
-"""get list of filesystems that are changed, compared to the latest snapshot"""
-def zfs_get_unchanged_filesystems(ssh_to, snapshots):
-
-    ret=[]
-    for ( filesystem, snapshot_list ) in snapshots.items():
-        latest_snapshot=snapshot_list[-1]
-
-        cmd=[
-            "zfs", "get","-H" ,"-ovalue", "written@"+latest_snapshot, filesystem
-        ]
-
-        output=run(ssh_to=ssh_to, tab_split=False, cmd=cmd, valid_exitcodes=[ 0 ])
-
-        if output[0]=="0B":
-            ret.append(filesystem)
-            verbose("No changes on {}".format(filesystem))
-
-    return(ret)
-
-
-def zfs_autobackup():
-
-
-
-    ############## data gathering section
-
-    if args.test:
-        args.verbose=True
-        verbose("RUNNING IN TEST-MODE, NOT MAKING ACTUAL BACKUP!")
-
-
-    ### getting and determinging source/target filesystems
-
-    # get selected filesystem on backup source
-    verbose("Getting selected source filesystems for backup {0} on {1}".format(args.backup_name,args.ssh_source))
-    source_filesystems=zfs_get_selected_filesystems(args.ssh_source, args.backup_name)
-
-    #nothing todo
-    if not source_filesystems:
-        error("No filesystems source selected, please do a 'zfs set autobackup:{0}=true' on {1}".format(args.backup_name,args.ssh_source))
-        sys.exit(1)
-
-
-    # determine target filesystems
-    target_filesystems=[]
-    for source_filesystem in source_filesystems:
-        #append args.target_fs prefix and strip args.strip_path paths from source_filesystem
-        target_filesystems.append(args.target_fs + "/" + lstrip_path(source_filesystem, args.strip_path))
-
-
-    ### get resumable transfers
-    resumable_target_filesystems={}
-    if args.resume:
-        verbose("Checking for aborted transfers that can be resumed")
-        resumable_target_filesystems=zfs_get_resumable_filesystems(args.ssh_target, target_filesystems)
-        debug("Resumable filesystems: "+str(pprint.pformat(resumable_target_filesystems)))
-
-
-    ### get all snapshots of all selected filesystems
-    verbose("Getting source snapshot-list from {0}".format(args.ssh_source))
-    source_snapshots=zfs_get_snapshots(args.ssh_source, source_filesystems, args.backup_name)
-    debug("Source snapshots: " + str(pprint.pformat(source_snapshots)))
-
-
-    #create new snapshot?
-    if not args.no_snapshot:
-        #determine which filesystems changed since last snapshot
-        if not args.allow_empty:
-            verbose("Determining unchanged filesystems")
-            unchanged_filesystems=zfs_get_unchanged_filesystems(args.ssh_source, source_snapshots)
-        else:
-            unchanged_filesystems=[]
-
-        snapshot_filesystems=[]
-        for source_filesystem in source_filesystems:
-            if source_filesystem not in unchanged_filesystems:
-                snapshot_filesystems.append(source_filesystem)
-
-
-        #create snapshot
-        if snapshot_filesystems:
-            new_snapshot_name=args.backup_name+"-"+time.strftime("%Y%m%d%H%M%S")
-            verbose("Creating source snapshot {0} on {1} ".format(new_snapshot_name, args.ssh_source))
-            zfs_create_snapshot(args.ssh_source, snapshot_filesystems, new_snapshot_name)
-        else:
-            verbose("No changes at all, not creating snapshot.")
-
-
-        #add it to the list of source filesystems
-        for snapshot_filesystem in snapshot_filesystems:
-            source_snapshots.setdefault(snapshot_filesystem,[]).append(new_snapshot_name)
-
-
-    #### get target snapshots
-    target_snapshots={}
-    try:
-        verbose("Getting target snapshot-list from {0}".format(args.ssh_target))
-        target_snapshots=zfs_get_snapshots(args.ssh_target, target_filesystems, args.backup_name)
-    except subprocess.CalledProcessError:
-        verbose("(ignoring errors, probably initial backup for this filesystem)")
-        pass
-    debug("Target snapshots: " + str(pprint.pformat(target_snapshots)))
-
-
-    #obsolete snapshots that may be removed
-    source_obsolete_snapshots={}
-    target_obsolete_snapshots={}
-
-
-
-    ############## backup section
-
-    #determine which snapshots to send for each filesystem
-    for source_filesystem in source_filesystems:
-        target_filesystem=args.target_fs + "/" + lstrip_path(source_filesystem, args.strip_path)
-
-        if source_filesystem not in source_snapshots:
-            #this happens if you use --no-snapshot and there are new filesystems without snapshots
-            verbose("Skipping source filesystem {0}, no snapshots found".format(source_filesystem))
-        else:
-
-            #incremental or initial send?
-            if target_filesystem in target_snapshots and target_snapshots[target_filesystem]:
-                #incremental mode, determine what to send and what is obsolete
-
-                #latest succesfully send snapshot, should be common on both source and target
-                latest_target_snapshot=target_snapshots[target_filesystem][-1]
-
-                if latest_target_snapshot not in source_snapshots[source_filesystem]:
-                    #cant find latest target anymore. find first common snapshot and inform user
-                    error_msg="Cant find latest target snapshot on source, did you destroy/rename it?"
-                    error_msg=error_msg+"\nLatest on target : "+target_filesystem+"@"+latest_target_snapshot
-                    error_msg=error_msg+"\nMissing on source: "+source_filesystem+"@"+latest_target_snapshot
-                    found=False
-                    for latest_target_snapshot in reversed(target_snapshots[target_filesystem]):
-                        if latest_target_snapshot in source_snapshots[source_filesystem]:
-                            error_msg=error_msg+"\nYou could solve this by rolling back to this common snapshot on target: "+target_filesystem+"@"+latest_target_snapshot
-                            found=True
-                            break
-                    if not found:
-                        error_msg=error_msg+"\nAlso could not find an earlier common snapshot to rollback to."
-
-                    raise(Exception(error_msg))
-
-                #send all new source snapshots that come AFTER the last target snapshot
-                latest_source_index=source_snapshots[source_filesystem].index(latest_target_snapshot)
-                send_snapshots=source_snapshots[source_filesystem][latest_source_index+1:]
-
-                #source snapshots that come BEFORE last target snapshot are obsolete
-                source_obsolete_snapshots[source_filesystem]=source_snapshots[source_filesystem][0:latest_source_index]
-
-                #target snapshots that come BEFORE last target snapshot are obsolete
-                latest_target_index=target_snapshots[target_filesystem].index(latest_target_snapshot)
-                target_obsolete_snapshots[target_filesystem]=target_snapshots[target_filesystem][0:latest_target_index]
-            else:
-                #initial mode, send all snapshots, nothing is obsolete:
-                latest_target_snapshot=None
-                send_snapshots=source_snapshots[source_filesystem]
-                target_obsolete_snapshots[target_filesystem]=[]
-                source_obsolete_snapshots[source_filesystem]=[]
-
-            #now actually send the snapshots
-            if not args.no_send:
-
-                if send_snapshots and args.rollback and latest_target_snapshot:
-                    #roll back any changes on target
-                    debug("Rolling back target to latest snapshot.")
-                    run(ssh_to=args.ssh_target, test=args.test, cmd=["zfs", "rollback", target_filesystem+"@"+latest_target_snapshot ])
-
-
-                for send_snapshot in send_snapshots:
-
-                    #resumable?
-                    if target_filesystem in resumable_target_filesystems:
-                        resume_token=resumable_target_filesystems.pop(target_filesystem)
-                    else:
-                        resume_token=None
-
-                    #hold the snapshot we're sending on the source
-                    zfs_hold_snapshot(ssh_to=args.ssh_source, snapshot=source_filesystem+"@"+send_snapshot)
-
-                    zfs_transfer(
-                        ssh_source=args.ssh_source, source_filesystem=source_filesystem,
-                        first_snapshot=latest_target_snapshot, second_snapshot=send_snapshot,
-                        ssh_target=args.ssh_target, target_filesystem=target_filesystem,
-                        resume_token=resume_token
-                    )
-
-                    #hold the snapshot we just send to the target
-                    zfs_hold_snapshot(ssh_to=args.ssh_target, snapshot=target_filesystem+"@"+send_snapshot)
-
-
-
-                    #now that we succesfully transferred this snapshot, the previous snapshot is obsolete:
-                    if latest_target_snapshot:
-                        zfs_release_snapshot(ssh_to=args.ssh_target, snapshot=target_filesystem+"@"+latest_target_snapshot)
-                        target_obsolete_snapshots[target_filesystem].append(latest_target_snapshot)
-
-                        zfs_release_snapshot(ssh_to=args.ssh_source, snapshot=source_filesystem+"@"+latest_target_snapshot)
-                        source_obsolete_snapshots[source_filesystem].append(latest_target_snapshot)
-                    #we just received a new filesytem?
-                    else:
-                        if args.clear_refreservation:
-                            debug("Clearing refreservation to save space.")
-
-                            run(ssh_to=args.ssh_target, test=args.test, cmd=["zfs", "set", "refreservation=none", target_filesystem ])
-
-
-                        if args.clear_mountpoint:
-                            debug("Setting canmount=noauto to prevent auto-mounting in the wrong place. (ignoring errors)")
-
-                            run(ssh_to=args.ssh_target, test=args.test, cmd=["zfs", "set", "canmount=noauto", target_filesystem ], valid_exitcodes= [0, 1] )
-
-
-                    latest_target_snapshot=send_snapshot
-
-
-
-    ############## cleanup section
-    #we only do cleanups after everything is complete, to keep everything consistent (same snapshots everywhere)
-
-
-    #find stale backups on target that have become obsolete
-    verbose("Getting stale filesystems and snapshots from {0}".format(args.ssh_target))
-    stale_target_filesystems=get_stale_backupped_filesystems(ssh_to=args.ssh_target, backup_name=args.backup_name, target_fs=args.target_fs, target_filesystems=target_filesystems)
-    debug("Stale target filesystems: {0}".format("\n".join(stale_target_filesystems)))
-
-    stale_target_snapshots=zfs_get_snapshots(args.ssh_target, stale_target_filesystems, args.backup_name)
-    debug("Stale target snapshots: " + str(pprint.pformat(stale_target_snapshots)))
-    target_obsolete_snapshots.update(stale_target_snapshots)
-
-    #determine stale filesystems that have no snapshots left (the can be destroyed)
-    #TODO: prevent destroying filesystems that have underlying filesystems that are still active.
-    stale_target_destroys=[]
-    for stale_target_filesystem in stale_target_filesystems:
-        if stale_target_filesystem not in stale_target_snapshots:
-            stale_target_destroys.append(stale_target_filesystem)
-
-    if stale_target_destroys:
-        if args.destroy_stale:
-            verbose("Destroying stale filesystems on target {0}:\n{1}".format(args.ssh_target, "\n".join(stale_target_destroys)))
-            zfs_destroy(ssh_to=args.ssh_target, filesystems=stale_target_destroys, recursive=True)
-        else:
-            verbose("Stale filesystems on {0}, use --destroy-stale to destroy:\n{1}".format(args.ssh_target, "\n".join(stale_target_destroys)))
-
-
-    #now actually destroy the old snapshots
-    source_destroys=determine_destroy_list(source_obsolete_snapshots, args.keep_source)
-    if source_destroys:
-        verbose("Destroying old snapshots on source {0}:\n{1}".format(args.ssh_source, "\n".join(source_destroys)))
-        zfs_destroy_snapshots(ssh_to=args.ssh_source, snapshots=source_destroys)
-
-    target_destroys=determine_destroy_list(target_obsolete_snapshots, args.keep_target)
-    if target_destroys:
-        verbose("Destroying old snapshots on target {0}:\n{1}".format(args.ssh_target, "\n".join(target_destroys)))
-        zfs_destroy_snapshots(ssh_to=args.ssh_target, snapshots=target_destroys)
-
-
-    verbose("All done")
-
-
-
-################################################################## ENTRY POINT
-
-# parse arguments
-import argparse
-parser = argparse.ArgumentParser(description='ZFS autobackup v2.2')
-parser.add_argument('--ssh-source', default="local", help='Source host to get backup from. (user@hostname) Default %(default)s.')
-parser.add_argument('--ssh-target', default="local", help='Target host to push backup to. (user@hostname) Default  %(default)s.')
-parser.add_argument('--keep-source', type=int, default=30, help='Number of days to keep old snapshots on source. Default %(default)s.')
-parser.add_argument('--keep-target', type=int, default=30, help='Number of days to keep old snapshots on target. Default %(default)s.')
-parser.add_argument('backup_name',    help='Name of the backup (you should set the zfs property "autobackup:backup-name" to true on filesystems you want to backup')
-parser.add_argument('target_fs',    help='Target filesystem')
-
-parser.add_argument('--no-snapshot', action='store_true', help='dont create new snapshot (usefull for finishing uncompleted backups, or cleanups)')
-parser.add_argument('--no-send', action='store_true', help='dont send snapshots (usefull to only do a cleanup)')
-parser.add_argument('--allow-empty', action='store_true', help='if nothing has changed, still create empty snapshots.')
-parser.add_argument('--resume', action='store_true', help='support resuming of interrupted transfers by using the zfs extensible_dataset feature (both zpools should have it enabled) Disadvantage is that you need to use zfs recv -A if another snapshot is created on the target during a receive. Otherwise it will keep failing.')
-parser.add_argument('--strip-path', default=0, type=int, help='number of directory to strip from path (use 1 when cloning zones between 2 SmartOS machines)')
-parser.add_argument('--buffer', default="",  help='Use mbuffer with specified size to speedup zfs transfer. (e.g. --buffer 1G)')
-
-
-parser.add_argument('--destroy-stale', action='store_true', help='Destroy stale backups that have no more snapshots. Be sure to verify the output before using this! ')
-parser.add_argument('--clear-refreservation', action='store_true', help='Set refreservation property to none for new filesystems. Usefull when backupping SmartOS volumes. (recommended)')
-parser.add_argument('--clear-mountpoint', action='store_true', help='Sets canmount=noauto property, to prevent the received filesystem from mounting over existing filesystems. (recommended)')
-parser.add_argument('--filter-properties', action='append', help='Filter properties when receiving filesystems. Can be specified multiple times. (Example: If you send data from Linux to FreeNAS, you should filter xattr)')
-parser.add_argument('--rollback', action='store_true', help='Rollback changes on the target before starting a backup. (normally you can prevent changes by setting the readonly property on the target_fs to on)')
-parser.add_argument('--ignore-transfer-errors', action='store_true', help='Ignore transfer errors (still checks if received filesystem exists. usefull for acltype errors)')
-
-
-parser.add_argument('--test', action='store_true', help='dont change anything, just show what would be done (still does all read-only operations)')
-parser.add_argument('--verbose', action='store_true', help='verbose output')
-parser.add_argument('--debug', action='store_true', help='debug output (shows commands that are executed)')
-
-#note args is the only global variable we use, since its a global readonly setting anyway
-args = parser.parse_args()
-
-try:
-    zfs_autobackup()
-except Exception as e:
-    if args.debug:
-        raise
-    else:
-        print("* ABORTED *")
-        print(str(e))