update version number

also changed internal logic: thinner now isnt actually created when --no-thinning is active.

When using --no-thinning --no-snapshot --no-send it still does usefull stuff like checking common snapshots and showing incompatible snapshots

.github/workflows/python-publish.yml

@@ -0,0 +1,46 @@
+# This workflow will upload a Python Package using Twine when a release is created
+# For more information see: https://help.github.com/en/actions/language-and-framework-guides/using-python-with-github-actions#publishing-to-package-registries
+
+name: Upload Python Package
+
+on:
+  release:
+    types: [created]
+
+jobs:
+  deploy:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Set up Python 3.x
+      uses: actions/setup-python@v2
+      with:
+        python-version: '3.x'
+
+    - name: Set up Python 2.x
+      uses: actions/setup-python@v2
+      with:
+        python-version: '2.x'
+
+    - name: Install dependencies 3.x
+      run: |
+        python -m pip install --upgrade pip
+        pip3 install setuptools wheel twine
+
+    - name: Install dependencies 2.x
+      run: |
+        python2 -m pip install --upgrade pip
+        pip2 install setuptools wheel twine
+
+    - name: Build and publish
+      env:
+        TWINE_USERNAME: ${{ secrets.TWINE_USERNAME }}
+        TWINE_PASSWORD: ${{ secrets.TWINE_PASSWORD }}
+      run: |
+        python3 setup.py sdist bdist_wheel
+        python2 setup.py sdist bdist_wheel
+        twine check dist/*
+        twine upload dist/*

.github/workflows/regression.yml

@@ -0,0 +1,76 @@
+name: Regression tests
+
+
+on: ["push", "pull_request"]
+
+
+
+jobs:
+
+  ubuntu20:
+    runs-on: ubuntu-20.04
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2.3.4
+
+
+
+      - name: Prepare
+        run: sudo apt update && sudo apt install zfsutils-linux lzop pigz zstd gzip xz-utils lz4 mbuffer && sudo -H pip3 install coverage unittest2 mock==3.0.5 coveralls
+
+
+      - name: Regression test
+        run: sudo -E ./tests/run_tests
+
+
+      - name: Coveralls
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: coveralls --service=github
+
+  ubuntu18:
+    runs-on: ubuntu-18.04
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2.3.4
+
+
+
+      - name: Prepare
+        run: sudo apt update && sudo apt install zfsutils-linux python3-setuptools lzop pigz zstd gzip xz-utils liblz4-tool mbuffer && sudo -H pip3 install coverage unittest2 mock==3.0.5 coveralls
+
+
+      - name: Regression test
+        run: sudo -E ./tests/run_tests
+
+
+      - name: Coveralls
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: coveralls --service=github
+
+  ubuntu18_python2:
+    runs-on: ubuntu-18.04
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2.3.4
+
+      - name: Set up Python 2.x
+        uses: actions/setup-python@v2
+        with:
+          python-version: '2.x'
+
+      - name: Prepare
+        run: sudo apt update && sudo apt install zfsutils-linux python-setuptools lzop pigz zstd gzip xz-utils liblz4-tool mbuffer && sudo -H pip install coverage unittest2 mock==3.0.5 coveralls colorama
+
+      - name: Regression test
+        run: sudo -E ./tests/run_tests
+
+      - name: Coveralls
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          COVERALLS_REPO_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: coveralls --service=github

.gitignore

@@ -1 +1,14 @@
 .vscode/settings.json
+token
+tokentest
+dist/
+build/
+zfs_autobackup.egg-info
+.eggs/
+__pycache__
+.coverage
+*.pyc
+python2.env
+venv
+.idea
+password.sh

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/>
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
- 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  Everyone is permitted to copy and distribute verbatim copies
  of this license document, but changing it is not allowed.
 
                             Preamble
 
-  The licenses for most software are designed to take away your
+  The GNU General Public License is a free, copyleft license for
-freedom to share and change it.  By contrast, the GNU General Public
+software and other kinds of works.
-License is intended to guarantee your freedom to share and change free
+
-software--to make sure the software is free for all its users.  This
+  The licenses for most software and other practical works are designed
-General Public License applies to most of the Free Software
+to take away your freedom to share and change the works.  By contrast,
-Foundation's software and to any other program whose authors commit to
+the GNU General Public License is intended to guarantee your freedom to
-using it.  (Some other Free Software Foundation software is covered by
+share and change all versions of a program--to make sure it remains free
-the GNU Lesser General Public License instead.)  You can apply it to
+software for all its users.  We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors.  You can apply it to
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   When we speak of free software, we are referring to freedom, not
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+them if you wish), that you receive source code or can get it if you
-if you want it, that you can change the software or use pieces of it
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   The precise terms and conditions for copying, distribution and
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-  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+  15. Disclaimer of Warranty.
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+
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+
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+
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                      END OF TERMS AND CONDITIONS
 
@@ -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}
+    <one line to give the program's name and a brief idea of what it does.>
-    Copyright (C) {year}  {fullname}
+    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
+    You should have received a copy of the GNU General Public License
-    with this program; if not, write to the Free Software Foundation, Inc.,
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
-    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
 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
+  If the program does terminal interaction, make it output a short
-when it starts in an interactive mode:
+notice like this when it starts in an interactive mode:
 
-    Gnomovision version 69, Copyright (C) year name of author
+    <program>  Copyright (C) <year>  <name of author>
-    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
     This is free software, and you are welcome to redistribute it
     under certain conditions; type `show c' for details.
 
 The hypothetical commands `show w' and `show c' should show the appropriate
-parts of the General Public License.  Of course, the commands you use may
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-be called something other than `show w' and `show c'; they could even be
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-necessary.  Here is a sample; alter the names:
+For more information on this, and how to apply and follow the GNU GPL, see
-
+<https://www.gnu.org/licenses/>.
-  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
-  `Gnomovision' (which makes passes at compilers) written by James Hacker.
-
-  {signature of Ty Coon}, 1 April 1989
-  Ty Coon, President of Vice
-
-This General Public License does not permit incorporating your program into
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-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
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+  The GNU General Public License does not permit incorporating your program
+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

@@ -1,18 +1,741 @@
-# ZFS autobackup v3 - TEST VERSION
 
-Official releases are here: https://github.com/psy0rz/zfs_autobackup/releases
+# ZFS autobackup
 
-New in v3:
+[![Tests](https://github.com/psy0rz/zfs_autobackup/workflows/Regression%20tests/badge.svg)](https://github.com/psy0rz/zfs_autobackup/actions?query=workflow%3A%22Regression+tests%22) [![Coverage Status](https://coveralls.io/repos/github/psy0rz/zfs_autobackup/badge.svg)](https://coveralls.io/github/psy0rz/zfs_autobackup)  [![Python Package](https://github.com/psy0rz/zfs_autobackup/workflows/Upload%20Python%20Package/badge.svg)](https://pypi.org/project/zfs-autobackup/)
- * Complete rewrite, cleaner object oriented code.
+
- * Python 3 and 2 support.
+## Introduction
- * Backwards compatible with your current backups and parameters.
+
- * Progressive thinning (via a destroy schedule. default schedule should be fine for most people)
+ZFS-autobackup tries to be the most reliable and easiest to use tool, while having all the features.
- * Cleaner output, with optional color support (pip install colorama). 
+
-   * Clear distinction between local and remote output.
+You can either use it as a **backup** tool, **replication** tool or **snapshot** tool.
-   * Summary at the beginning, displaying what will happen and the current thinning-schedule.
+
- * More effient destroying/skipping snaphots on the fly. (no more space issues if your backup is way behind)
+You can select what to backup by setting a custom `ZFS property`. This makes it easy to add/remove specific datasets, or just backup your whole pool.
- * Progress indicator (--progress)
+
- * Better property management (--set-properties and --filter-properties)
+Other settings are just specified on the commandline: Simply setup and test your zfs-autobackup command and  fix all the issues you might encounter. When you're done you can just copy/paste your command to a cron or script.
- * Better resume handling, automaticly abort invalid resumes.
+
- * More robust error handling.
+Since its using ZFS commands, you can see what it's 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. (something I missed in other tools)
- * Prepared for future enhanchements.
+
+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 system.
+
+## Features
+
+* Works across operating systems: Tested with **Linux**, **FreeBSD/FreeNAS** and **SmartOS**.
+* Low learning curve: no complex daemons or services, no additional software or networking needed. (Only read this page)   
+* Plays nicely 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, atomicly.)
+* 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.
+  * Or even pull data from a server while pushing the backup to another server. (Zero trust between source and target server)
+* Can be scheduled via a simple cronjob or run directly from commandline.
+* Supports resuming of interrupted transfers.
+* ZFS encryption support: Can decrypt / encrypt or even re-encrypt datasets during transfer.
+* Supports sending with compression. (Using pigz, zstd etc)
+* IO buffering to speed up transfer.
+* Bandwidth rate limiting.
+* Multiple backups from and to the same datasets are no problem.
+* Creates the snapshot before doing anything else. (assuring you at least have a snapshot if all else fails)
+* 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.
+* 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 datasets that no longer exist on source.
+* Support for ZFS sending/receiving through custom pipes.
+* Easy installation:
+  * Just install zfs-autobackup via pip.
+  * Only needs to be installed on one side.
+  * Written in python and uses zfs-commands, no special 3rd party dependency's or compiled libraries needed.
+  * No separate config files or properties. Just one zfs-autobackup command you can copy/paste in your backup script.
+
+## Installation
+
+You only need to install zfs-autobackup on the side that initiates the backup. The other side doesnt need any extra configration.
+
+### Using pip
+
+The recommended way on most servers is to use [pip](https://pypi.org/project/zfs-autobackup/):
+
+```console
+[root@server ~]# pip install --upgrade zfs-autobackup
+```
+
+This can also be used to upgrade zfs-autobackup to the newest stable version.
+
+To install the latest beta version add the `--pre` option.
+
+### Using easy_install
+
+On older servers you might have to use easy_install
+
+```console
+[root@server ~]# easy_install zfs-autobackup
+```
+
+## 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
+...
+```
+
+ZFS properties are ```inherited``` by child datasets. Since we've set the property on the highest dataset, we're essentially backupping the whole pool.
+
+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
+...
+```
+
+The autobackup-property can have 3 values:
+ * ```true```: Backup the dataset and all its children 
+ * ```false```: Dont backup the dataset and all its children. (used to exclude certain datasets)
+ * ```child```: Only backup the children off the dataset, not the dataset itself.
+
+Only use the zfs-command to set these properties, not the zpool command. 
+
+### Running zfs-autobackup
+
+Run the script on the backup server and pull the data from the server specified by --ssh-source.
+
+```console
+[root@backup ~]# zfs-autobackup --ssh-source server1.server.com offsite1 backup/server1 --progress --verbose
+
+  #### 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
+  ...
+```
+
+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 - 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.)
+```
+
+This also allows you to make several snapshots during the day, but only backup the data at night when the server is not busy.
+
+## Thinning out obsolete snapshots
+
+The thinner is the thing that destroys old snapshots on the source and target.
+
+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)
+
+## How zfs-autobackup handles encryption
+
+In normal operation datasets are transferred unaltered:
+
+* Source datasets that are encrypted will be send over as such and stay encrypted at the target side. (In ZFS this is called raw-mode) You dont need keys at the target side if you dont want to access the data.
+* Source datasets that are plain will stay that way on the target. (Even if the specified target-path IS encrypted.) 
+
+Basically you dont have to do anything or worry about anything. 
+
+### Decrypting/encrypting
+
+Things get different if you want to change the encryption-state of a dataset during transfer:
+
+* If you want to decrypt encrypted datasets before sending them, you should use the `--decrypt` option. Datasets will then be stored plain at the target.
+* If you want to encrypt plain datasets when they are received, you should use the `--encrypt` option. Datasets will then be stored encrypted at the target. (Datasets that are already encrypted will still be sent over unaltered in raw-mode.) 
+* If you also want re-encrypt encrypted datasets with the target-side encryption you can use both options. 
+
+Note 1: The --encrypt option will rely on inheriting encryption parameters from the parent datasets on the target side. You are responsible for setting those up and loading the keys. So --encrypt is no guarantee for encryption: If you dont set it up, it cant encrypt.
+
+Note 2: Decide what you want at an early stage: If you change the --encrypt or --decrypt parameter after the inital sync you might get weird and wonderfull errors. (nothing dangerous)
+
+I'll add some tips when the issues start to get in on github. :)
+
+## Transfer buffering, compression and rate limiting.
+
+If you're transferring over a slow link it might be useful to use `--compress=zstd-fast`. This will compres the data before sending, so it uses less bandwidth.
+
+You can also limit the datarate by using the `--rate` option.
+
+The `--buffer` option might also help since it acts as an IO buffer: zfs send can vary wildly between completely idle and huge bursts of data. When zfs send is idle, the buffer will continue transferring data over the slow link.
+
+It's also possible to add custom send or receive pipes with `--send-pipe` and `--recv-pipe`.
+
+These options all work together and the buffer on the receiving side is only added if appropriate. When all options are active:
+
+#### On the sending side:
+
+zfs send -> send buffer -> custom send pipes -> compression -> transfer rate limiter
+
+#### On the receiving side:
+decompression -> custom recv pipes -> buffer -> zfs recv
+
+## 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.
+
+### Performance tips
+
+If you have a large number of datasets its important to keep the following tips in mind.
+
+Also it might help to use the --buffer option to add IO buffering during the data transfer. This might speed up things since it smooths out sudden IO bursts that are frequent during a zfs send or recv.
+
+#### Some statistics
+
+To get some idea of how fast zfs-autobackup is, I did some test on my laptop, with a SKHynix_HFS512GD9TNI-L2B0B disk. I'm using zfs 2.0.2.  
+
+I created 100 empty datasets and measured the total runtime of zfs-autobackup. I used all the performance tips below. (--no-holds, --allow-empty, ssh ControlMaster)
+
+* without ssh: 15 seconds. (>6 datasets/s)
+* either ssh-target or ssh-source=localhost: 20 seconds (5 datasets/s)
+* both ssh-target and ssh-source=localhost: 24 seconds (4 datasets/s)
+
+To be bold I created 2500 datasets, but that also was no problem. So it seems it should be possible to use zfs-autobackup with thousands of datasets.
+
+If you need more performance let me know.
+
+NOTE: There is actually a performance regression in ZFS version 2: https://github.com/openzfs/zfs/issues/11560 Use --no-progress as workaround.
+
+#### Less work
+
+You can make zfs-autobackup generate less work by using --no-holds and --allow-empty.
+
+This saves a lot of extra zfs-commands per dataset.
+
+#### 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
+```
+
+Thanks @mariusvw :)
+
+### 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
+    user root
+    Compression yes
+```
+
+This way you can just specify "smartos04" as host.
+
+Also uses compression on slow links.
+
+Look in man ssh_config for many more options.
+
+## Usage
+
+(NOTE: Quite a lot has changed since the current stable version 3.0. The page your are viewing is for upcoming version 3.1 which is still in beta.)
+
+```console
+usage: zfs-autobackup [-h] [--ssh-config CONFIG-FILE] [--ssh-source USER@HOST]
+                      [--ssh-target USER@HOST] [--keep-source SCHEDULE]
+                      [--keep-target SCHEDULE] [--other-snapshots]
+                      [--no-snapshot] [--no-send] [--no-thinning] [--no-holds]
+                      [--min-change BYTES] [--allow-empty]
+                      [--ignore-replicated] [--strip-path N]
+                      [--clear-refreservation] [--clear-mountpoint]
+                      [--filter-properties PROPERY,...]
+                      [--set-properties PROPERTY=VALUE,...] [--rollback]
+                      [--destroy-incompatible] [--destroy-missing SCHEDULE]
+                      [--ignore-transfer-errors] [--decrypt] [--encrypt]
+                      [--test] [--verbose] [--debug] [--debug-output]
+                      [--progress] [--send-pipe COMMAND] [--recv-pipe COMMAND]
+                      [--compress TYPE] [--rate DATARATE] [--buffer SIZE]
+                      backup-name [target-path]
+
+zfs-autobackup v3.1-beta6 - (c)2021 E.H.Eefting (edwin@datux.nl)
+
+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 CONFIG-FILE
+                        Custom ssh client config
+  --ssh-source USER@HOST
+                        Source host to get backup from.
+  --ssh-target USER@HOST
+                        Target host to push backup to.
+  --keep-source SCHEDULE
+                        Thinning schedule for old source snapshots. Default:
+                        10,1d1w,1w1m,1m1y
+  --keep-target SCHEDULE
+                        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)
+  --no-thinning         Do not destroy any snapshots.
+  --no-holds            Don't hold snapshots. (Faster. Allows you to destroy
+                        common snapshot.)
+  --min-change BYTES    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)
+
+  --strip-path N        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 PROPERY,...
+                        List of properties to "filter" when receiving
+                        filesystems. (you can still restore them with zfs
+                        inherit -S)
+  --set-properties PROPERTY=VALUE,...
+                        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)
+  --destroy-missing SCHEDULE
+                        Destroy datasets on target that are missing on the
+                        source. Specify the time since the last snapshot, e.g:
+                        --destroy-missing 30d
+  --ignore-transfer-errors
+                        Ignore transfer errors (still checks if received
+                        filesystem exists. useful for acltype errors)
+  --decrypt             Decrypt data before sending it over.
+  --encrypt             Encrypt data after receiving it.
+  --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. Enabled automaticly on ttys.
+                        (use --no-progress to disable)
+  --send-pipe COMMAND   pipe zfs send output through COMMAND (can be used
+                        multiple times)
+  --recv-pipe COMMAND   pipe zfs recv input through COMMAND (can be used
+                        multiple times)
+  --compress TYPE       Use compression during transfer, zstd-fast
+                        recommended. (zstd-slow, xz, pigz-fast, lz4, pigz-
+                        slow, zstd-fast, gzip, lzo)
+  --rate DATARATE       Limit data transfer rate (e.g. 128K. requires
+                        mbuffer.)
+  --buffer SIZE         Add zfs send and recv buffers to smooth out IO bursts.
+                        (e.g. 128M. requires mbuffer)
+
+Full manual at: https://github.com/psy0rz/zfs_autobackup
+```
+
+## 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 'cannot receive incremental stream: destination has been modified since most recent snapshot'
+
+This means files have been modified on the target side somehow. 
+
+You can use --rollback to automaticly rollback such changes. Also try destroying the target dataset and using --clear-mountpoint on the next run. This way it wont get mounted.
+
+### 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 or --ignore-transfer-errors. 
+
+### zfs receive fails, but snapshot seems to be received successful.
+
+This happens if you transfer between different Operating systems/zfs versions or feature sets.
+
+Try using the --ignore-transfer-errors option. This will ignore the error. It will still check if the snapshot is actually received correctly.
+
+## 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
+
+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 exit code and will also alert you if the job didn't run for more than 2 days.
+
+## Backup 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 pve1, pve2 and pve3.
+
+### Preparing the proxmox nodes
+
+No preparation is needed, the script will take care of everything. You only need to setup the ssh keys, so that the backup server can access the proxmox server.
+
+TIP: make sure your backup server is firewalled and cannot be reached from any production machine.
+
+### SSH config on backup server
+
+I use ~/.ssh/config to specify how to reach the various hosts.
+
+In this example we are making an offsite copy and use portforwarding to reach the proxmox machines:
+```
+Host *
+    ControlPath ~/.ssh/control-master-%r@%h:%p
+    ControlMaster auto
+    ControlPersist 3600
+    Compression yes
+
+Host pve1
+    Hostname some.host.com
+    Port 10001
+
+Host pve2
+    Hostname some.host.com
+    Port 10002
+
+Host pve3
+    Hostname some.host.com
+    Port 10003
+```
+
+### Backup script
+
+I use the following backup script on the backup server.
+
+Adjust the variables HOSTS TARGET and NAME to your needs.
+
+```shell
+#!/bin/bash
+
+HOSTS="pve1 pve2 pve3"
+TARGET=rpool/pvebackups
+NAME=prox
+
+zfs create -p $TARGET/data &>/dev/null
+for HOST in $HOSTS; do
+
+  echo "################################### RPOOL $HOST"
+
+  # enable backup
+  ssh $HOST "zfs set autobackup:rpool_$NAME=child rpool/ROOT"
+
+  #backup rpool to specific directory per host
+  zfs create -p $TARGET/rpools/$HOST &>/dev/null
+  zfs-autobackup --keep-source=1d1w,1w1m --ssh-source $HOST rpool_$NAME $TARGET/rpools/$HOST --clear-mountpoint --clear-refreservation --ignore-transfer-errors --strip-path 2 --verbose   --no-holds   $@
+
+  zabbix-job-status backup_$HOST""_rpool_$NAME daily $? >/dev/null 2>/dev/null
+
+
+  echo "################################### DATA $HOST"
+
+  # enable backup
+  ssh $HOST "zfs set autobackup:data_$NAME=child rpool/data"
+
+  #backup data filesystems to a common directory
+  zfs-autobackup --keep-source=1d1w,1w1m --ssh-source $HOST data_$NAME $TARGET/data --clear-mountpoint --clear-refreservation --ignore-transfer-errors --strip-path 2 --verbose  --ignore-replicated --min-change 200000 --no-holds   $@
+
+  zabbix-job-status backup_$HOST""_data_$NAME daily $? >/dev/null 2>/dev/null
+
+done
+```
+
+This script will also send the backup status to Zabbix. (if you've installed my zabbix-job-status script https://github.com/psy0rz/stuff/tree/master/zabbix-jobs)
+
+# Sponsor list
+
+This project was sponsorred by:
+
+* JetBrains (Provided me with a license for their whole professional product line, https://www.jetbrains.com/pycharm/ )

requirements.txt

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

scripts/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

scripts/releasetest

@@ -0,0 +1,16 @@
+#!/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

setup.py

@@ -0,0 +1,37 @@
+import setuptools
+from zfs_autobackup.ZfsAutobackup import ZfsAutobackup
+import os
+
+with open("README.md", "r") as fh:
+    long_description = fh.read()
+
+setuptools.setup(
+    name="zfs_autobackup",
+    version=ZfsAutobackup.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",
+    entry_points={
+        'console_scripts':
+            [
+                'zfs-autobackup = zfs_autobackup:cli',
+            ]
+    },
+    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"
+    ]
+)

tests/autoruntests

@@ -0,0 +1,6 @@
+#!/bin/bash
+
+#NOTE: run from top directory
+
+find tests/*.py zfs_autobackup/*.py| entr -r ./tests/run_tests $@
+

tests/basetest.py

@@ -0,0 +1,94 @@
+
+# To run tests as non-root, use this hack:
+# chmod 4755 /usr/sbin/zpool /usr/sbin/zfs
+
+import subprocess
+import random
+
+#default test stuff
+import unittest2
+import subprocess
+import time
+from pprint import *
+from zfs_autobackup.ZfsAutobackup 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("SUDO_ASKPASS=./password.sh sudo -A "+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")

tests/run_tests

@@ -0,0 +1,28 @@
+#!/bin/bash 
+
+SCRIPTDIR=`dirname $0`
+
+#cd $SCRIPTDIR || exit 1
+
+
+if [ "$USER" != "root" ]; then
+    echo "Need root to do proper zfs testing"
+    exit 1
+fi
+
+
+# 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 --branch --source zfs_autobackup -m unittest discover -vvvvf $SCRIPTDIR $@ 2>&1
+EXIT=$?
+
+echo
+coverage report
+
+exit $EXIT

tests/test_cmdpipe.py

@@ -0,0 +1,123 @@
+from basetest import *
+from zfs_autobackup.CmdPipe import CmdPipe,CmdItem
+
+
+class TestCmdPipe(unittest2.TestCase):
+
+    def test_single(self):
+        """single process stdout and stderr"""
+        p=CmdPipe(readonly=False, inp=None)
+        err=[]
+        out=[]
+        p.add(CmdItem(["ls", "-d", "/", "/", "/nonexistent"], stderr_handler=lambda line: err.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,2)))
+        executed=p.execute(stdout_handler=lambda line: out.append(line))
+
+        self.assertEqual(err, ["ls: cannot access '/nonexistent': No such file or directory"])
+        self.assertEqual(out, ["/","/"])
+        self.assertIsNone(executed)
+
+    def test_input(self):
+        """test stdinput"""
+        p=CmdPipe(readonly=False, inp="test")
+        err=[]
+        out=[]
+        p.add(CmdItem(["cat"], stderr_handler=lambda line: err.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,0)))
+        executed=p.execute(stdout_handler=lambda line: out.append(line))
+
+        self.assertEqual(err, [])
+        self.assertEqual(out, ["test"])
+        self.assertIsNone(executed)
+
+    def test_pipe(self):
+        """test piped"""
+        p=CmdPipe(readonly=False)
+        err1=[]
+        err2=[]
+        err3=[]
+        out=[]
+        p.add(CmdItem(["echo", "test"], stderr_handler=lambda line: err1.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,0)))
+        p.add(CmdItem(["tr", "e", "E"], stderr_handler=lambda line: err2.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,0)))
+        p.add(CmdItem(["tr", "t", "T"], stderr_handler=lambda line: err3.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,0)))
+        executed=p.execute(stdout_handler=lambda line: out.append(line))
+
+        self.assertEqual(err1, [])
+        self.assertEqual(err2, [])
+        self.assertEqual(err3, [])
+        self.assertEqual(out, ["TEsT"])
+        self.assertIsNone(executed)
+
+        #test str representation as well
+        self.assertEqual(str(p), "(echo test) | (tr e E) | (tr t T)")
+
+    def test_pipeerrors(self):
+        """test piped stderrs """
+        p=CmdPipe(readonly=False)
+        err1=[]
+        err2=[]
+        err3=[]
+        out=[]
+        p.add(CmdItem(["ls", "/nonexistent1"], stderr_handler=lambda line: err1.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,2)))
+        p.add(CmdItem(["ls", "/nonexistent2"], stderr_handler=lambda line: err2.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,2)))
+        p.add(CmdItem(["ls", "/nonexistent3"], stderr_handler=lambda line: err3.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,2)))
+        executed=p.execute(stdout_handler=lambda line: out.append(line))
+
+        self.assertEqual(err1, ["ls: cannot access '/nonexistent1': No such file or directory"])
+        self.assertEqual(err2, ["ls: cannot access '/nonexistent2': No such file or directory"])
+        self.assertEqual(err3, ["ls: cannot access '/nonexistent3': No such file or directory"])
+        self.assertEqual(out, [])
+        self.assertIsNone(executed)
+
+    def test_exitcode(self):
+        """test piped exitcodes """
+        p=CmdPipe(readonly=False)
+        err1=[]
+        err2=[]
+        err3=[]
+        out=[]
+        p.add(CmdItem(["bash", "-c", "exit 1"], stderr_handler=lambda line: err1.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,1)))
+        p.add(CmdItem(["bash", "-c", "exit 2"], stderr_handler=lambda line: err2.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,2)))
+        p.add(CmdItem(["bash", "-c", "exit 3"], stderr_handler=lambda line: err3.append(line), exit_handler=lambda exit_code: self.assertEqual(exit_code,3)))
+        executed=p.execute(stdout_handler=lambda line: out.append(line))
+
+        self.assertEqual(err1, [])
+        self.assertEqual(err2, [])
+        self.assertEqual(err3, [])
+        self.assertEqual(out, [])
+        self.assertIsNone(executed)
+
+    def test_readonly_execute(self):
+        """everything readonly, just should execute"""
+
+        p=CmdPipe(readonly=True)
+        err1=[]
+        err2=[]
+        out=[]
+
+        def true_exit(exit_code):
+            return True
+
+        p.add(CmdItem(["echo", "test1"], stderr_handler=lambda line: err1.append(line), exit_handler=true_exit, readonly=True))
+        p.add(CmdItem(["echo", "test2"], stderr_handler=lambda line: err2.append(line), exit_handler=true_exit, readonly=True))
+        executed=p.execute(stdout_handler=lambda line: out.append(line))
+
+        self.assertEqual(err1, [])
+        self.assertEqual(err2, [])
+        self.assertEqual(out, ["test2"])
+        self.assertTrue(executed)
+
+    def test_readonly_skip(self):
+        """one command not readonly, skip"""
+
+        p=CmdPipe(readonly=True)
+        err1=[]
+        err2=[]
+        out=[]
+        p.add(CmdItem(["echo", "test1"], stderr_handler=lambda line: err1.append(line), readonly=False))
+        p.add(CmdItem(["echo", "test2"], stderr_handler=lambda line: err2.append(line), readonly=True))
+        executed=p.execute(stdout_handler=lambda line: out.append(line))
+
+        self.assertEqual(err1, [])
+        self.assertEqual(err2, [])
+        self.assertEqual(out, [])
+        self.assertTrue(executed)
+

tests/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 --no-progress --verbose --no-holds".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000000"): #far in past
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --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 --destroy-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 --no-progress --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 --no-progress --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
+""")

tests/test_encryption.py

@@ -0,0 +1,192 @@
+from zfs_autobackup.CmdPipe import CmdPipe
+from basetest import *
+import time
+
+# We have to do a LOT to properly test encryption/decryption/raw transfers
+#
+# For every scenario we need at least:
+# - plain source dataset
+# - encrypted source dataset
+# - plain target path
+# - encrypted target path
+# - do a full transfer
+# - do a incremental transfer
+
+# Scenarios:
+# - Raw transfer
+# - Decryption transfer (--decrypt)
+# - Encryption transfer (--encrypt)
+# - Re-encryption transfer (--decrypt --encrypt)
+
+class TestZfsEncryption(unittest2.TestCase):
+
+
+    def setUp(self):
+        prepare_zpools()
+
+        try:
+            shelltest("zfs get encryption test_source1")
+        except:
+            self.skipTest("Encryption not supported on this ZFS version.")
+
+    def prepare_encrypted_dataset(self, key, path, unload_key=False):
+
+        # create encrypted source dataset
+        shelltest("echo {} > /tmp/zfstest.key".format(key))
+        shelltest("zfs create -o keylocation=file:///tmp/zfstest.key -o keyformat=passphrase -o encryption=on {}".format(path))
+
+        if unload_key:
+            shelltest("zfs unmount {}".format(path))
+            shelltest("zfs unload-key {}".format(path))
+
+        # r=shelltest("dd if=/dev/zero of=/test_source1/fs1/enc1/data.txt bs=200000 count=1")
+
+    def  test_raw(self):
+        """send encrypted data unaltered (standard operation)"""
+
+        self.prepare_encrypted_dataset("11111111", "test_source1/fs1/encryptedsource")
+        self.prepare_encrypted_dataset("11111111", "test_source1/fs1/encryptedsourcekeyless", unload_key=True) # raw mode shouldn't need a key
+        self.prepare_encrypted_dataset("22222222", "test_target1/encryptedtarget")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-progress --allow-empty --exclude-received".split(" ")).run())
+            self.assertFalse(ZfsAutobackup("test test_target1/encryptedtarget --verbose --no-progress --no-snapshot --exclude-received".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-progress --allow-empty --exclude-received".split(" ")).run())
+            self.assertFalse(ZfsAutobackup("test test_target1/encryptedtarget --verbose --no-progress --no-snapshot --exclude-received".split(" ")).run())
+
+        r = shelltest("zfs get -r -t filesystem encryptionroot test_target1")
+        self.assertMultiLineEqual(r,"""
+NAME                                                                  PROPERTY        VALUE                                                                 SOURCE
+test_target1                                                          encryptionroot  -                                                                     -
+test_target1/encryptedtarget                                          encryptionroot  test_target1/encryptedtarget                                          -
+test_target1/encryptedtarget/test_source1                             encryptionroot  test_target1/encryptedtarget                                          -
+test_target1/encryptedtarget/test_source1/fs1                         encryptionroot  -                                                                     -
+test_target1/encryptedtarget/test_source1/fs1/encryptedsource         encryptionroot  test_target1/encryptedtarget/test_source1/fs1/encryptedsource         -
+test_target1/encryptedtarget/test_source1/fs1/encryptedsourcekeyless  encryptionroot  test_target1/encryptedtarget/test_source1/fs1/encryptedsourcekeyless  -
+test_target1/encryptedtarget/test_source1/fs1/sub                     encryptionroot  -                                                                     -
+test_target1/encryptedtarget/test_source2                             encryptionroot  test_target1/encryptedtarget                                          -
+test_target1/encryptedtarget/test_source2/fs2                         encryptionroot  test_target1/encryptedtarget                                          -
+test_target1/encryptedtarget/test_source2/fs2/sub                     encryptionroot  -                                                                     -
+test_target1/test_source1                                             encryptionroot  -                                                                     -
+test_target1/test_source1/fs1                                         encryptionroot  -                                                                     -
+test_target1/test_source1/fs1/encryptedsource                         encryptionroot  test_target1/test_source1/fs1/encryptedsource                         -
+test_target1/test_source1/fs1/encryptedsourcekeyless                  encryptionroot  test_target1/test_source1/fs1/encryptedsourcekeyless                  -
+test_target1/test_source1/fs1/sub                                     encryptionroot  -                                                                     -
+test_target1/test_source2                                             encryptionroot  -                                                                     -
+test_target1/test_source2/fs2                                         encryptionroot  -                                                                     -
+test_target1/test_source2/fs2/sub                                     encryptionroot  -                                                                     -
+""")
+
+    def  test_decrypt(self):
+        """decrypt data and store unencrypted (--decrypt)"""
+
+        self.prepare_encrypted_dataset("11111111", "test_source1/fs1/encryptedsource")
+        self.prepare_encrypted_dataset("22222222", "test_target1/encryptedtarget")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-progress --decrypt --allow-empty --exclude-received".split(" ")).run())
+            self.assertFalse(ZfsAutobackup("test test_target1/encryptedtarget --verbose --no-progress --decrypt --no-snapshot --exclude-received".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-progress --decrypt --allow-empty --exclude-received".split(" ")).run())
+            self.assertFalse(ZfsAutobackup("test test_target1/encryptedtarget --verbose --no-progress --decrypt --no-snapshot --exclude-received".split(" ")).run())
+
+        r = shelltest("zfs get -r -t filesystem encryptionroot test_target1")
+        self.assertEqual(r, """
+NAME                                                           PROPERTY        VALUE                         SOURCE
+test_target1                                                   encryptionroot  -                             -
+test_target1/encryptedtarget                                   encryptionroot  test_target1/encryptedtarget  -
+test_target1/encryptedtarget/test_source1                      encryptionroot  test_target1/encryptedtarget  -
+test_target1/encryptedtarget/test_source1/fs1                  encryptionroot  -                             -
+test_target1/encryptedtarget/test_source1/fs1/encryptedsource  encryptionroot  -                             -
+test_target1/encryptedtarget/test_source1/fs1/sub              encryptionroot  -                             -
+test_target1/encryptedtarget/test_source2                      encryptionroot  test_target1/encryptedtarget  -
+test_target1/encryptedtarget/test_source2/fs2                  encryptionroot  test_target1/encryptedtarget  -
+test_target1/encryptedtarget/test_source2/fs2/sub              encryptionroot  -                             -
+test_target1/test_source1                                      encryptionroot  -                             -
+test_target1/test_source1/fs1                                  encryptionroot  -                             -
+test_target1/test_source1/fs1/encryptedsource                  encryptionroot  -                             -
+test_target1/test_source1/fs1/sub                              encryptionroot  -                             -
+test_target1/test_source2                                      encryptionroot  -                             -
+test_target1/test_source2/fs2                                  encryptionroot  -                             -
+test_target1/test_source2/fs2/sub                              encryptionroot  -                             -
+""")
+
+    def  test_encrypt(self):
+        """send normal data set and store encrypted on the other side (--encrypt) issue #60 """
+
+        self.prepare_encrypted_dataset("11111111", "test_source1/fs1/encryptedsource")
+        self.prepare_encrypted_dataset("22222222", "test_target1/encryptedtarget")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-progress --encrypt --debug --allow-empty --exclude-received".split(" ")).run())
+            self.assertFalse(ZfsAutobackup("test test_target1/encryptedtarget --verbose --no-progress --encrypt --debug --no-snapshot --exclude-received".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --no-progress --encrypt --debug --allow-empty --exclude-received".split(" ")).run())
+            self.assertFalse(ZfsAutobackup("test test_target1/encryptedtarget --verbose --no-progress --encrypt --debug --no-snapshot --exclude-received".split(" ")).run())
+
+        r = shelltest("zfs get -r -t filesystem encryptionroot test_target1")
+        self.assertEqual(r, """
+NAME                                                           PROPERTY        VALUE                                                          SOURCE
+test_target1                                                   encryptionroot  -                                                              -
+test_target1/encryptedtarget                                   encryptionroot  test_target1/encryptedtarget                                   -
+test_target1/encryptedtarget/test_source1                      encryptionroot  test_target1/encryptedtarget                                   -
+test_target1/encryptedtarget/test_source1/fs1                  encryptionroot  test_target1/encryptedtarget                                   -
+test_target1/encryptedtarget/test_source1/fs1/encryptedsource  encryptionroot  test_target1/encryptedtarget/test_source1/fs1/encryptedsource  -
+test_target1/encryptedtarget/test_source1/fs1/sub              encryptionroot  test_target1/encryptedtarget                                   -
+test_target1/encryptedtarget/test_source2                      encryptionroot  test_target1/encryptedtarget                                   -
+test_target1/encryptedtarget/test_source2/fs2                  encryptionroot  test_target1/encryptedtarget                                   -
+test_target1/encryptedtarget/test_source2/fs2/sub              encryptionroot  test_target1/encryptedtarget                                   -
+test_target1/test_source1                                      encryptionroot  -                                                              -
+test_target1/test_source1/fs1                                  encryptionroot  -                                                              -
+test_target1/test_source1/fs1/encryptedsource                  encryptionroot  test_target1/test_source1/fs1/encryptedsource                  -
+test_target1/test_source1/fs1/sub                              encryptionroot  -                                                              -
+test_target1/test_source2                                      encryptionroot  -                                                              -
+test_target1/test_source2/fs2                                  encryptionroot  -                                                              -
+test_target1/test_source2/fs2/sub                              encryptionroot  -                                                              -
+""")
+
+    def test_reencrypt(self):
+        """reencrypt data (--decrypt --encrypt) """
+
+        self.prepare_encrypted_dataset("11111111", "test_source1/fs1/encryptedsource")
+        self.prepare_encrypted_dataset("22222222", "test_target1/encryptedtarget")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup(
+                "test test_target1 --verbose --no-progress --decrypt --encrypt --debug --allow-empty --exclude-received".split(" ")).run())
+            self.assertFalse(ZfsAutobackup(
+                "test test_target1/encryptedtarget --verbose --no-progress --decrypt --encrypt --debug --no-snapshot --exclude-received".split(
+                    " ")).run())
+
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup(
+                "test test_target1 --verbose --no-progress --decrypt --encrypt --debug --allow-empty --exclude-received".split(" ")).run())
+            self.assertFalse(ZfsAutobackup(
+                "test test_target1/encryptedtarget --verbose --no-progress --decrypt --encrypt --debug --no-snapshot --exclude-received".split(
+                    " ")).run())
+
+        r = shelltest("zfs get -r -t filesystem encryptionroot test_target1")
+        self.assertEqual(r, """
+NAME                                                           PROPERTY        VALUE                         SOURCE
+test_target1                                                   encryptionroot  -                             -
+test_target1/encryptedtarget                                   encryptionroot  test_target1/encryptedtarget  -
+test_target1/encryptedtarget/test_source1                      encryptionroot  test_target1/encryptedtarget  -
+test_target1/encryptedtarget/test_source1/fs1                  encryptionroot  test_target1/encryptedtarget  -
+test_target1/encryptedtarget/test_source1/fs1/encryptedsource  encryptionroot  test_target1/encryptedtarget  -
+test_target1/encryptedtarget/test_source1/fs1/sub              encryptionroot  test_target1/encryptedtarget  -
+test_target1/encryptedtarget/test_source2                      encryptionroot  test_target1/encryptedtarget  -
+test_target1/encryptedtarget/test_source2/fs2                  encryptionroot  test_target1/encryptedtarget  -
+test_target1/encryptedtarget/test_source2/fs2/sub              encryptionroot  test_target1/encryptedtarget  -
+test_target1/test_source1                                      encryptionroot  -                             -
+test_target1/test_source1/fs1                                  encryptionroot  -                             -
+test_target1/test_source1/fs1/encryptedsource                  encryptionroot  -                             -
+test_target1/test_source1/fs1/sub                              encryptionroot  -                             -
+test_target1/test_source2                                      encryptionroot  -                             -
+test_target1/test_source2/fs2                                  encryptionroot  -                             -
+test_target1/test_source2/fs2/sub                              encryptionroot  -                             -
+""")
+

tests/test_executenode.py

@@ -0,0 +1,148 @@
+from basetest import *
+from zfs_autobackup.ExecuteNode 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(ExecuteError):
+                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
+        with self.subTest("escape test"):
+            s="><`'\"@&$()$bla\\/.* !#test _+-={}[]|${bla} $bla"
+            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"], inp="test"), ["test"])
+
+        #command that wants input, while we dont have input, shouldnt hang forever.
+        with self.subTest("stdin process with inp=None (shouldn't hang)"):
+            self.assertEqual(node.run(["cat"]), [])
+
+        # let the system do the piping with an unescaped |:
+        with self.subTest("system piping test"):
+
+            #first make sure the actual | character is still properly escaped:
+            self.assertEqual(node.run(["echo","|"]), ["|"])
+
+            #now pipe
+            self.assertEqual(node.run(["echo", "abc", node.PIPE, "tr", "a", "A" ]), ["Abc"])
+
+    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), [])
+        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"], inp=output), ["816df6f64deba63b029ca19d880ee10a  -"])
+
+        with self.subTest("exit code both ends of pipe ok"):
+            output=nodea.run(["true"], pipe=True)
+            nodeb.run(["true"], inp=output)
+
+        with self.subTest("error on pipe input side"):
+            with self.assertRaises(ExecuteError):
+                output=nodea.run(["false"], pipe=True)
+                nodeb.run(["true"], inp=output)
+
+        with self.subTest("error on both sides, ignore exit codes"):
+            output=nodea.run(["false"], pipe=True, valid_exitcodes=[])
+            nodeb.run(["false"], inp=output, valid_exitcodes=[])
+
+        with self.subTest("error on pipe output side "):
+            with self.assertRaises(ExecuteError):
+                output=nodea.run(["true"], pipe=True)
+                nodeb.run(["false"], inp=output)
+
+        with self.subTest("error on both sides of pipe"):
+            with self.assertRaises(ExecuteError):
+                output=nodea.run(["false"], pipe=True)
+                nodeb.run(["false"], inp=output)
+
+        with self.subTest("check stderr on pipe output side"):
+            output=nodea.run(["true"], pipe=True, valid_exitcodes=[0])
+            (stdout, stderr)=nodeb.run(["ls", "nonexistingfile"], inp=output, return_stderr=True, valid_exitcodes=[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, valid_exitcodes=[2])
+            (stdout, stderr)=nodeb.run(["true"], inp=output, return_stderr=True, valid_exitcodes=[0])
+            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()

tests/test_externalfailures.py

@@ -0,0 +1,314 @@
+from basetest import *
+
+
+class TestExternalFailures(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 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --verbose --test".split(" ")).run())
+
+        # try again, should abort old resume
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --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 --no-progress --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 --no-progress --verbose --test".split(" ")).run())
+
+        # try again, should abort old resume
+        with patch('time.strftime', return_value="20101111000002"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --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 --no-progress --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 --no-progress --verbose --keep-target=0 --allow-empty".split(" ")).run())
+
+            print(buf.getvalue())
+
+            self.assertIn("Aborting resume, we dont want that snapshot anymore.", 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
+""")
+
+    # test with empty snapshot list (this was a bug)
+    def test_abort_resume_emptysnapshotlist(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 --no-progress --verbose".split(" ")).run())
+
+        # generate resume
+        with patch('time.strftime', return_value="20101111000001"):
+            self.generate_resume()
+
+        shelltest("zfs destroy test_source1/fs1@test-20101111000001")
+
+        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 --no-progress --verbose --no-snapshot".split(
+                            " ")).run())
+
+            print(buf.getvalue())
+
+            self.assertIn("Aborting resume, its obsolete", buf.getvalue())
+
+
+    def test_missing_common(self):
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --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 --no-progress --verbose --allow-empty".split(" ")).run())
+
+    #UPDATE: offcourse the one thing that wasn't tested had a bug :(  (in ExecuteNode.run()).
+    def test_ignoretransfererrors(self):
+
+            self.skipTest("Not sure how to implement a test for this without some serious hacking and patching.")
+
+#         #recreate target pool without any features
+#         # shelltest("zfs set compress=on test_source1; zpool destroy test_target1; zpool create test_target1 -o feature@project_quota=disabled /dev/ram2")
+#
+#         with patch('time.strftime', return_value="20101111000000"):
+#             self.assertFalse(ZfsAutobackup("test test_target1 --verbose --allow-empty --no-progress".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-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
+#         """)

tests/test_log.py

@@ -0,0 +1,52 @@
+import zfs_autobackup.LogConsole
+from basetest import *
+
+
+class TestLog(unittest2.TestCase):
+
+    def test_colored(self):
+        """test with color output"""
+        with OutputIO() as buf:
+            with redirect_stdout(buf):
+                l=LogConsole(show_verbose=False, show_debug=False, color=True)
+                l.verbose("verbose")
+                l.debug("debug")
+
+            with redirect_stdout(buf):
+                l=LogConsole(show_verbose=True, show_debug=True, color=True)
+                l.verbose("verbose")
+                l.debug("debug")
+
+            with redirect_stderr(buf):
+                l=LogConsole(show_verbose=False, show_debug=False, color=True)
+                l.error("error")
+
+            print(list(buf.getvalue()))
+            self.assertEqual(list(buf.getvalue()), ['\x1b', '[', '2', '2', 'm', ' ', ' ', 'v', 'e', 'r', 'b', 'o', 's', 'e', '\x1b', '[', '0', 'm', '\n', '\x1b', '[', '3', '2', 'm', '#', ' ', 'd', 'e', 'b', 'u', 'g', '\x1b', '[', '0', 'm', '\n', '\x1b', '[', '3', '1', 'm', '\x1b', '[', '1', 'm', '!', ' ', 'e', 'r', 'r', 'o', 'r', '\x1b', '[', '0', 'm', '\n'])
+
+    def test_nocolor(self):
+        """test without color output"""
+
+        with OutputIO() as buf:
+            with redirect_stdout(buf):
+                l=LogConsole(show_verbose=False, show_debug=False, color=False)
+                l.verbose("verbose")
+                l.debug("debug")
+
+            with redirect_stdout(buf):
+                l=LogConsole(show_verbose=True, show_debug=True, color=False)
+                l.verbose("verbose")
+                l.debug("debug")
+
+            with redirect_stderr(buf):
+                l=LogConsole(show_verbose=False, show_debug=False, color=False)
+                l.error("error")
+
+            print(list(buf.getvalue()))
+            self.assertEqual(list(buf.getvalue()), [' ', ' ', 'v', 'e', 'r', 'b', 'o', 's', 'e', '\n', '#', ' ', 'd', 'e', 'b', 'u', 'g', '\n', '!', ' ', 'e', 'r', 'r', 'o', 'r', '\n'])
+
+
+        zfs_autobackup.LogConsole.colorama=False
+
+
+

tests/test_regressions.py

@@ -0,0 +1,19 @@
+
+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())

tests/test_scaling.py

@@ -0,0 +1,97 @@
+from basetest import *
+
+from zfs_autobackup.ExecuteNode import ExecuteNode
+
+run_orig=ExecuteNode.run
+run_counter=0
+
+def run_count(*args, **kwargs):
+    global run_counter
+    run_counter=run_counter+1
+    return (run_orig(*args, **kwargs))
+
+class TestZfsScaling(unittest2.TestCase):
+
+    def setUp(self):
+        prepare_zpools()
+        self.longMessage = True
+
+    def test_manysnapshots(self):
+        """count the number of commands when there are many snapshots."""
+
+        snapshot_count=100
+
+        print("Creating many snapshots...")
+        s=""
+        for i in range(1970,1970+snapshot_count):
+            s=s+"zfs snapshot test_source1/fs1@test-{:04}1111000000;".format(i)
+
+        shelltest(s)
+
+        global run_counter
+
+        run_counter=0
+        with patch.object(ExecuteNode,'run', run_count) as p:
+
+            with patch('time.strftime', return_value="20101112000000"):
+                self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --verbose --keep-source=10000 --keep-target=10000 --no-holds --allow-empty".split(" ")).run())
+
+
+            #this triggers if you make a change with an impact of more than O(snapshot_count/2)
+            expected_runs=343
+            print("ACTUAL RUNS: {}".format(run_counter))
+            self.assertLess(abs(run_counter-expected_runs), snapshot_count/2)
+
+
+        run_counter=0
+        with patch.object(ExecuteNode,'run', run_count) as p:
+
+            with patch('time.strftime', return_value="20101112000001"):
+                self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --verbose --keep-source=10000 --keep-target=10000 --no-holds --allow-empty".split(" ")).run())
+
+
+            #this triggers if you make a change with a performance impact of more than O(snapshot_count/2)
+            expected_runs=47
+            print("ACTUAL RUNS: {}".format(run_counter))
+            self.assertLess(abs(run_counter-expected_runs), snapshot_count/2)
+
+    def test_manydatasets(self):
+        """count the number of commands when when there are many datasets"""
+
+        dataset_count=100
+
+        print("Creating many datasets...")
+        s=""
+        for i in range(0,dataset_count):
+            s=s+"zfs create test_source1/fs1/{};".format(i)
+
+        shelltest(s)
+
+        global run_counter
+
+        #first run
+        run_counter=0
+        with patch.object(ExecuteNode,'run', run_count) as p:
+
+            with patch('time.strftime', return_value="20101112000000"):
+                self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --verbose --no-holds --allow-empty".split(" ")).run())
+
+
+            #this triggers if you make a change with an impact of more than O(snapshot_count/2)
+            expected_runs=743
+            print("ACTUAL RUNS: {}".format(run_counter))
+            self.assertLess(abs(run_counter-expected_runs), dataset_count/2)
+
+
+        #second run, should have higher number of expected_runs
+        run_counter=0
+        with patch.object(ExecuteNode,'run', run_count) as p:
+
+            with patch('time.strftime', return_value="20101112000001"):
+                self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --verbose --no-holds --allow-empty".split(" ")).run())
+
+
+            #this triggers if you make a change with a performance impact of more than O(snapshot_count/2)
+            expected_runs=947
+            print("ACTUAL RUNS: {}".format(run_counter))
+            self.assertLess(abs(run_counter-expected_runs), dataset_count/2)

tests/test_sendrecvpipes.py

@@ -0,0 +1,88 @@
+import zfs_autobackup.compressors
+from basetest import *
+import time
+
+class TestSendRecvPipes(unittest2.TestCase):
+    """test input/output pipes for zfs send and recv"""
+
+    def setUp(self):
+        prepare_zpools()
+        self.longMessage=True
+
+
+
+    def test_send_basics(self):
+        """send basics (remote/local send pipe)"""
+
+
+        with self.subTest("local local pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1", "--exclude-received", "--no-holds", "--no-progress", "--send-pipe=dd bs=1M",  "--recv-pipe=dd bs=2M"]).run())
+
+            shelltest("zfs destroy -r test_target1/test_source1/fs1/sub")
+
+        with self.subTest("remote local pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1", "--exclude-received", "--no-holds", "--no-progress", "--ssh-source=localhost", "--send-pipe=dd bs=1M",  "--recv-pipe=dd bs=2M"]).run())
+
+            shelltest("zfs destroy -r test_target1/test_source1/fs1/sub")
+
+        with self.subTest("local remote pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1",  "--exclude-received", "--no-holds", "--no-progress", "--ssh-target=localhost", "--send-pipe=dd bs=1M",  "--recv-pipe=dd bs=2M"]).run())
+
+            shelltest("zfs destroy -r test_target1/test_source1/fs1/sub")
+
+        with self.subTest("remote remote pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1",  "--exclude-received", "--no-holds", "--no-progress", "--ssh-source=localhost", "--ssh-target=localhost", "--send-pipe=dd bs=1M",  "--recv-pipe=dd bs=2M"]).run())
+
+    def test_compress(self):
+        """send basics (remote/local send pipe)"""
+
+        for compress in zfs_autobackup.compressors.COMPRESS_CMDS.keys():
+
+            with self.subTest("compress "+compress):
+                with patch('time.strftime', return_value="20101111000000"):
+                    self.assertFalse(ZfsAutobackup(["test", "test_target1", "--exclude-received", "--no-holds", "--no-progress", "--compress="+compress]).run())
+
+                shelltest("zfs destroy -r test_target1/test_source1/fs1/sub")
+
+    def test_buffer(self):
+        """test different buffer configurations"""
+
+
+        with self.subTest("local local pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1", "--exclude-received", "--no-holds", "--no-progress", "--buffer=1M" ]).run())
+
+            shelltest("zfs destroy -r test_target1/test_source1/fs1/sub")
+
+        with self.subTest("remote local pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1", "--exclude-received", "--no-holds", "--no-progress", "--ssh-source=localhost", "--buffer=1M"]).run())
+
+            shelltest("zfs destroy -r test_target1/test_source1/fs1/sub")
+
+        with self.subTest("local remote pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1",  "--exclude-received", "--no-holds", "--no-progress", "--ssh-target=localhost", "--buffer=1M"]).run())
+
+            shelltest("zfs destroy -r test_target1/test_source1/fs1/sub")
+
+        with self.subTest("remote remote pipe"):
+            with patch('time.strftime', return_value="20101111000000"):
+                self.assertFalse(ZfsAutobackup(["test", "test_target1",  "--exclude-received", "--no-holds", "--no-progress", "--ssh-source=localhost", "--ssh-target=localhost", "--buffer=1M"]).run())
+
+    def test_rate(self):
+        """test rate limit"""
+
+
+        start=time.time()
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup(["test", "test_target1", "--exclude-received", "--no-holds", "--no-progress", "--rate=50k" ]).run())
+
+        #not a great way of verifying but it works.
+        self.assertGreater(time.time()-start, 5)
+
+

tests/test_thinner.py

@@ -0,0 +1,159 @@
+from basetest import *
+import pprint
+
+from zfs_autobackup.Thinner import Thinner
+
+# 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_exceptions(self):
+        with self.assertRaisesRegexp(Exception, "^Invalid period"):
+            ThinnerRule("12X12m")
+
+        with self.assertRaisesRegexp(Exception, "^Invalid ttl"):
+            ThinnerRule("12d12X")
+
+        with self.assertRaisesRegexp(Exception, "^Period cant be"):
+            ThinnerRule("12d1d")
+
+        with self.assertRaisesRegexp(Exception, "^Invalid schedule"):
+            ThinnerRule("XXX")
+
+        with self.assertRaisesRegexp(Exception, "^Number of"):
+            Thinner("-1")
+
+
+    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()

tests/test_zfsautobackup.py

@@ -0,0 +1,905 @@
+from zfs_autobackup.CmdPipe import CmdPipe
+
+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 --no-progress --keep-source -1".split(" ")).run(), 255)
+
+        with OutputIO() as buf:
+            with redirect_stdout(buf):
+                self.assertEqual(ZfsAutobackup("test test_target1 --no-progress --resume --verbose --no-snapshot".split(" ")).run(), 0)
+
+            print(buf.getvalue())
+            self.assertIn("The --resume", buf.getvalue())
+
+        with OutputIO() as buf:
+            with redirect_stderr(buf):
+                self.assertEqual(ZfsAutobackup("test test_target_nonexisting --no-progress".split(" ")).run(), 255)
+
+            print(buf.getvalue())
+            # correct message?
+            self.assertIn("Please create this dataset", buf.getvalue())
+
+
+    def  test_snapshotmode(self):
+        """test snapshot tool mode"""
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test --no-progress --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@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_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 --no-progress".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 --no-progress".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 --no-progress".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 --no-progress".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 --no-progress".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 --no-progress --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 --no-progress --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 --no-progress".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 --no-progress".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 --no-progress --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 --no-progress".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  0         -
+test_target1/test_source1/fs1/sub                      userrefs  -         -
+test_target1/test_source1/fs1/sub@test-20101111000000  userrefs  0         -
+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         -
+""")
+
+
+    def  test_strippath(self):
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --verbose --strip-path=1 --no-progress".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 --no-progress --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 --no-progress --verbose --clear-mountpoint --debug".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 --no-progress --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 --no-progress --verbose --allow-empty".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000002"):
+            #rollback, should succeed
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --verbose --allow-empty --test".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000002"):
+            #should fail, now incompatible
+            self.assertTrue(ZfsAutobackup("test test_target1 --no-progress --verbose --allow-empty".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000003"):
+            #--test should succeed by destroying incompatibles
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --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 --no-progress --verbose --allow-empty --destroy-incompatible".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@compatible1
+test_target1/test_source1/fs1@compatible2
+test_target1/test_source1/fs1@test-20101111000001
+test_target1/test_source1/fs1@test-20101111000002
+test_target1/test_source1/fs1@test-20101111000003
+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_source1/fs1/sub@test-20101111000003
+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
+test_target1/test_source2/fs2/sub@test-20101111000003
+""")
+
+
+
+
+
+
+    def test_ssh(self):
+
+        #test all ssh directions
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --verbose --allow-empty --ssh-source localhost --exclude-received".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --verbose --allow-empty --ssh-target localhost --exclude-received".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000002"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --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 --no-progress --verbose".split(" ")).run())
+
+
+        #test incremental
+        with patch('time.strftime', return_value="20101111000002"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --allow-empty --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 --no-progress --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
+""")
+
+    def test_keep0(self):
+        """test if keep-source=0 and keep-target=0 dont delete common snapshot and break backup"""
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --verbose --keep-source=0 --keep-target=0".split(" ")).run())
+
+        #make snapshot, shouldnt delete 0
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test --no-progress --verbose --keep-source=0 --keep-target=0 --allow-empty".split(" ")).run())
+
+        #make snapshot 2, shouldnt delete 0 since it has holds, but will delete 1 since it has no holds
+        with patch('time.strftime', return_value="20101111000002"):
+            self.assertFalse(ZfsAutobackup("test --no-progress --verbose --keep-source=0 --keep-target=0 --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-20101111000002
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000000
+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-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/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
+""")
+
+        #make another backup but with no-holds. we should naturally endup with only number 3
+        with patch('time.strftime', return_value="20101111000003"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --verbose --keep-source=0 --keep-target=0 --no-holds --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-20101111000003
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000003
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000003
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000003
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000003
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000003
+""")
+
+
+        # make snapshot 4, since we used no-holds, it will delete 3 on the source, breaking the backup
+        with patch('time.strftime', return_value="20101111000004"):
+            self.assertFalse(ZfsAutobackup("test --no-progress --verbose --keep-source=0 --keep-target=0 --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-20101111000004
+test_source1/fs1/sub
+test_source1/fs1/sub@test-20101111000004
+test_source2
+test_source2/fs2
+test_source2/fs2/sub
+test_source2/fs2/sub@test-20101111000004
+test_source2/fs3
+test_source2/fs3/sub
+test_target1
+test_target1/test_source1
+test_target1/test_source1/fs1
+test_target1/test_source1/fs1@test-20101111000003
+test_target1/test_source1/fs1/sub
+test_target1/test_source1/fs1/sub@test-20101111000003
+test_target1/test_source2
+test_target1/test_source2/fs2
+test_target1/test_source2/fs2/sub
+test_target1/test_source2/fs2/sub@test-20101111000003
+""")
+
+
+    def test_progress(self):
+
+        r=shelltest("dd if=/dev/zero of=/test_source1/data.txt bs=200000 count=1")
+        r = shelltest("zfs snapshot test_source1@test")
+
+        l=LogConsole(show_verbose=True, show_debug=False, color=False)
+        n=ZfsNode("test",l)
+        d=ZfsDataset(n,"test_source1@test")
+
+        sp=d.send_pipe([], prev_snapshot=None, resume_token=None, show_progress=True, raw=False, send_pipes=[], send_properties=True, write_embedded=True, zfs_compressed=True)
+
+
+        with OutputIO() as buf:
+            with redirect_stderr(buf):
+                try:
+                    n.run(["sleep", "2"], inp=sp)
+                except:
+                    pass
+
+            print(buf.getvalue())
+            # correct message?
+            self.assertRegex(buf.getvalue(),".*>>> .*minutes left.*")

tests/test_zfsautobackup31.py

@@ -0,0 +1,81 @@
+from basetest import *
+import time
+
+class TestZfsAutobackup31(unittest2.TestCase):
+    """various new 3.1 features"""
+
+    def setUp(self):
+        prepare_zpools()
+        self.longMessage=True
+
+    def test_no_thinning(self):
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --verbose --allow-empty".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1 --no-progress --verbose --allow-empty --keep-target=0 --keep-source=0 --no-thinning".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
+""")
+
+
+    def test_re_replication(self):
+        """test re-replication of something thats already a backup (new in v3.1-beta5)"""
+
+        shelltest("zfs create test_target1/a")
+        shelltest("zfs create test_target1/b")
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(ZfsAutobackup("test test_target1/a --no-progress --verbose --debug".split(" ")).run())
+
+        with patch('time.strftime', return_value="20101111000001"):
+            self.assertFalse(ZfsAutobackup("test test_target1/b --no-progress --verbose".split(" ")).run())
+
+            r=shelltest("zfs list -H -o name -r -t snapshot test_target1")
+            #NOTE: it wont backup test_target1/a/test_source2/fs2/sub to test_target1/b since it doesnt have the zfs_autobackup property anymore.
+            self.assertMultiLineEqual(r,"""
+test_target1/a/test_source1/fs1@test-20101111000000
+test_target1/a/test_source1/fs1/sub@test-20101111000000
+test_target1/a/test_source2/fs2/sub@test-20101111000000
+test_target1/b/test_source1/fs1@test-20101111000000
+test_target1/b/test_source1/fs1/sub@test-20101111000000
+test_target1/b/test_source2/fs2/sub@test-20101111000000
+test_target1/b/test_target1/a/test_source1/fs1@test-20101111000000
+test_target1/b/test_target1/a/test_source1/fs1/sub@test-20101111000000
+""")
+
+    def test_zfs_compressed(self):
+
+        with patch('time.strftime', return_value="20101111000000"):
+            self.assertFalse(
+                ZfsAutobackup("test test_target1 --no-progress --verbose --debug --zfs-compressed".split(" ")).run())
+

tests/test_zfsnode.py

@@ -0,0 +1,125 @@
+from basetest import *
+from zfs_autobackup.LogStub import LogStub
+
+
+
+class TestZfsNode(unittest2.TestCase):
+
+    def setUp(self):
+        prepare_zpools()
+        # return super().setUp()
+
+
+    def test_consistent_snapshot(self):
+        logger=LogStub()
+        description="[Source]"
+        node=ZfsNode("test", logger, description=description)
+
+        with self.subTest("first snapshot"):
+            node.consistent_snapshot(node.selected_datasets(exclude_paths=[], exclude_received=False), "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(exclude_paths=[], exclude_received=False), "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(exclude_paths=[], exclude_received=False), "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=LogStub()
+        description="[Source]"
+        node=ZfsNode("test", logger, description=description)
+        s=pformat(node.selected_datasets(exclude_paths=[], exclude_received=False))
+        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=LogStub()
+        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=LogStub()
+        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=LogStub()
+        description="[Source]"
+        #NOTE: this could 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/CachedProperty.py

@@ -0,0 +1,39 @@
+# NOTE: this should inherit from (object) to function correctly with python 2.7
+class CachedProperty(object):
+    """ A property that is only computed once per instance and
+    then stores the result in _cached_properties of the object.
+
+        Source: https://github.com/bottlepy/bottle/commit/fa7733e075da0d790d809aa3d2f53071897e6f76
+        """
+
+    def __init__(self, func):
+        self.__doc__ = getattr(func, '__doc__')
+        self.func = func
+
+    def __get__(self, obj, cls):
+        if obj is None:
+            return self
+
+        propname = self.func.__name__
+
+        if not hasattr(obj, '_cached_properties'):
+            obj._cached_properties = {}
+
+        if propname not in obj._cached_properties:
+            obj._cached_properties[propname] = self.func(obj)
+            # value = obj.__dict__[propname] = self.func(obj)
+
+        return obj._cached_properties[propname]
+
+    @staticmethod
+    def clear(obj):
+        """clears cache of obj"""
+        if hasattr(obj, '_cached_properties'):
+            obj._cached_properties = {}
+
+    @staticmethod
+    def is_cached(obj, propname):
+        if hasattr(obj, '_cached_properties') and propname in obj._cached_properties:
+            return True
+        else:
+            return False

zfs_autobackup/CmdPipe.py

@@ -0,0 +1,160 @@
+import subprocess
+import os
+import select
+
+try:
+    from shlex import quote as cmd_quote
+except ImportError:
+    from pipes import quote as cmd_quote
+
+
+class CmdItem:
+    """one command item, to be added to a CmdPipe"""
+
+    def __init__(self, cmd, readonly=False, stderr_handler=None, exit_handler=None, shell=False):
+        """create item. caller has to make sure cmd is properly escaped when using shell.
+        :type cmd: list of str
+        """
+
+        self.cmd = cmd
+        self.readonly = readonly
+        self.stderr_handler = stderr_handler
+        self.exit_handler = exit_handler
+        self.shell = shell
+        self.process = None
+
+    def __str__(self):
+        """return copy-pastable version of command."""
+        if self.shell:
+            # its already copy pastable for a shell:
+            return " ".join(self.cmd)
+        else:
+            # make it copy-pastable, will make a mess of quotes sometimes, but is correct
+            return " ".join(map(cmd_quote, self.cmd))
+
+    def create(self, stdin):
+        """actually create the subprocess (called by CmdPipe)"""
+
+        # make sure the command gets all the data in utf8 format:
+        # (this is necessary if LC_ALL=en_US.utf8 is not set in the environment)
+        encoded_cmd = []
+        for arg in self.cmd:
+            encoded_cmd.append(arg.encode('utf-8'))
+
+        self.process = subprocess.Popen(encoded_cmd, env=os.environ, stdout=subprocess.PIPE, stdin=stdin,
+                                        stderr=subprocess.PIPE, shell=self.shell)
+
+
+class CmdPipe:
+    """a pipe of one or more commands. also takes care of utf-8 encoding/decoding and line based parsing"""
+
+    def __init__(self, readonly=False, inp=None):
+        """
+        :param inp: input string for stdin
+        :param readonly: Only execute if entire pipe consist of readonly commands
+        """
+        # list of commands + error handlers to execute
+        self.items = []
+
+        self.inp = inp
+        self.readonly = readonly
+        self._should_execute = True
+
+    def add(self, cmd_item):
+        """adds a CmdItem to pipe.
+        :type cmd_item: CmdItem
+        """
+
+        self.items.append(cmd_item)
+
+        if not cmd_item.readonly and self.readonly:
+            self._should_execute = False
+
+    def __str__(self):
+        """transform whole pipe into oneliner for debugging and testing. this should generate a copy-pastable string for in a console """
+
+        ret = ""
+        for item in self.items:
+            if ret:
+                ret = ret + " | "
+            ret = ret + "({})".format(item)  # this will do proper escaping to make it copypastable
+
+        return ret
+
+    def should_execute(self):
+        return self._should_execute
+
+    def execute(self, stdout_handler):
+        """run the pipe. returns True all exit handlers returned true"""
+
+        if not self._should_execute:
+            return True
+
+        # first process should have actual user input as stdin:
+        selectors = []
+
+        # create processes
+        last_stdout = None
+        stdin = subprocess.PIPE
+        for item in self.items:
+
+            item.create(stdin)
+            selectors.append(item.process.stderr)
+
+            if last_stdout is None:
+                # we're the first process in the pipe, do we have some input?
+                if self.inp is not None:
+                    # TODO: make streaming to support big inputs?
+                    item.process.stdin.write(self.inp.encode('utf-8'))
+                item.process.stdin.close()
+            else:
+                # last stdout was piped to this stdin already, so close it because we dont need it anymore
+                last_stdout.close()
+
+            last_stdout = item.process.stdout
+            stdin = last_stdout
+
+        # monitor last stdout as well
+        selectors.append(last_stdout)
+
+        while True:
+            # wait for output on one of the stderrs or last_stdout
+            (read_ready, write_ready, ex_ready) = select.select(selectors, [], [])
+            eof_count = 0
+            done_count = 0
+
+            # read line and call appropriate handlers
+            if last_stdout in read_ready:
+                line = last_stdout.readline().decode('utf-8').rstrip()
+                if line != "":
+                    stdout_handler(line)
+                else:
+                    eof_count = eof_count + 1
+
+            for item in self.items:
+                if item.process.stderr in read_ready:
+                    line = item.process.stderr.readline().decode('utf-8').rstrip()
+                    if line != "":
+                        item.stderr_handler(line)
+                    else:
+                        eof_count = eof_count + 1
+
+                if item.process.poll() is not None:
+                    done_count = done_count + 1
+
+            # all filehandles are eof and all processes are done (poll() is not None)
+            if eof_count == len(selectors) and done_count == len(self.items):
+                break
+
+        # close filehandles
+        last_stdout.close()
+        for item in self.items:
+            item.process.stderr.close()
+
+        # call exit handlers
+        success = True
+        for item in self.items:
+            if item.exit_handler is not None:
+                success=item.exit_handler(item.process.returncode) and success
+
+        return success

zfs_autobackup/ExecuteNode.py

@@ -0,0 +1,161 @@
+import os
+import select
+import subprocess
+from zfs_autobackup.CmdPipe import CmdPipe, CmdItem
+from zfs_autobackup.LogStub import LogStub
+
+try:
+    from shlex import quote as cmd_quote
+except ImportError:
+    from pipes import quote as cmd_quote
+
+
+class ExecuteError(Exception):
+    pass
+
+
+class ExecuteNode(LogStub):
+    """an endpoint to execute local or remote commands via ssh"""
+
+    PIPE=1
+
+    def __init__(self, ssh_config=None, ssh_to=None, readonly=False, debug_output=False):
+        """ssh_config: custom ssh config
+           ssh_to: server you want to ssh to. none means local
+           readonly: only execute commands that don't make any changes (useful for testing-runs)
+           debug_output: show output and exit codes of commands in debugging output.
+        """
+
+        self.ssh_config = ssh_config
+        self.ssh_to = ssh_to
+        self.readonly = readonly
+        self.debug_output = debug_output
+
+    def __repr__(self):
+        if self.ssh_to is None:
+            return "(local)"
+        else:
+            return self.ssh_to
+
+    def _parse_stdout(self, line):
+        """parse stdout. can be overridden in subclass"""
+        if self.debug_output:
+            self.debug("STDOUT > " + line.rstrip())
+
+    def _parse_stderr(self, line, hide_errors):
+        """parse stderr. can be overridden in subclass"""
+        if hide_errors:
+            self.debug("STDERR > " + line.rstrip())
+        else:
+            self.error("STDERR > " + line.rstrip())
+
+    def _quote(self, cmd):
+        """return quoted version of command. if it has value PIPE it will add an actual | """
+        if cmd==self.PIPE:
+            return('|')
+        else:
+            return(cmd_quote(cmd))
+
+    def _shell_cmd(self, cmd):
+        """prefix specified ssh shell to command and escape shell characters"""
+
+        ret=[]
+
+        #add remote shell
+        if not self.is_local():
+            ret=["ssh"]
+
+            if self.ssh_config is not None:
+                ret.extend(["-F", self.ssh_config])
+
+            ret.append(self.ssh_to)
+
+        ret.append(" ".join(map(self._quote, cmd)))
+
+        return ret
+
+    def is_local(self):
+        return self.ssh_to is None
+
+    def run(self, cmd, inp=None, tab_split=False, valid_exitcodes=None, readonly=False, hide_errors=False,
+            return_stderr=False, pipe=False):
+        """run a command on the node , checks output and parses/handle output and returns it
+
+        Either uses a local shell (sh -c) or remote shell (ssh) to execute the command. Therefore the command can have stuff like actual pipes in it, if you dont want to use pipe=True to pipe stuff.
+
+        :param cmd: the actual command, should be a list, where the first item is the command
+                    and the rest are parameters. use ExecuteNode.PIPE to add an unescaped |
+                    (if you want to use system piping instead of python piping)
+        :param pipe: return CmdPipe instead of executing it.
+        :param inp: Can be None, a string or a CmdPipe that was previously returned.
+        :param tab_split: split tabbed files in output into a list
+        :param valid_exitcodes: list of valid exit codes for this command (checks exit code of both sides of a pipe)
+                                Use [] to accept all exit codes. Default [0]
+        :param readonly: make this True if the command doesn't make any changes and is safe to execute in testmode
+        :param hide_errors: don't show stderr output as error, instead show it as debugging output (use to hide expected errors)
+        :param return_stderr: return both stdout and stderr as a tuple. (normally only returns stdout)
+
+        """
+
+        # create new pipe?
+        if not isinstance(inp, CmdPipe):
+            cmd_pipe = CmdPipe(self.readonly, inp)
+        else:
+            # add stuff to existing pipe
+            cmd_pipe = inp
+
+        # stderr parser
+        error_lines = []
+
+        def stderr_handler(line):
+            if tab_split:
+                error_lines.append(line.rstrip().split('\t'))
+            else:
+                error_lines.append(line.rstrip())
+            self._parse_stderr(line, hide_errors)
+
+        # exit code hanlder
+        if valid_exitcodes is None:
+            valid_exitcodes = [0]
+
+        def exit_handler(exit_code):
+            if self.debug_output:
+                self.debug("EXIT   > {}".format(exit_code))
+
+            if (valid_exitcodes != []) and (exit_code not in valid_exitcodes):
+                self.error("Command \"{}\" returned exit code {} (valid codes: {})".format(cmd_item, exit_code, valid_exitcodes))
+                return False
+
+            return True
+
+        # add shell command and handlers to pipe
+        cmd_item=CmdItem(cmd=self._shell_cmd(cmd), readonly=readonly, stderr_handler=stderr_handler, exit_handler=exit_handler, shell=self.is_local())
+        cmd_pipe.add(cmd_item)
+
+        # return pipe instead of executing?
+        if pipe:
+            return cmd_pipe
+
+        # stdout parser
+        output_lines = []
+
+        def stdout_handler(line):
+            if tab_split:
+                output_lines.append(line.rstrip().split('\t'))
+            else:
+                output_lines.append(line.rstrip())
+            self._parse_stdout(line)
+
+        if cmd_pipe.should_execute():
+            self.debug("CMD    > {}".format(cmd_pipe))
+        else:
+            self.debug("CMDSKIP> {}".format(cmd_pipe))
+
+        # execute and calls handlers in CmdPipe
+        if not cmd_pipe.execute(stdout_handler=stdout_handler):
+            raise(ExecuteError("Last command returned error"))
+
+        if return_stderr:
+            return output_lines, error_lines
+        else:
+            return output_lines

zfs_autobackup/LogConsole.py

@@ -0,0 +1,66 @@
+# python 2 compatibility
+from __future__ import print_function
+
+import sys
+
+class LogConsole:
+    """Log-class that outputs to console, adding colors if needed"""
+
+    def __init__(self, show_debug, show_verbose, color):
+        self.last_log = ""
+        self.show_debug = show_debug
+        self.show_verbose = show_verbose
+
+        if color:
+            # try to use color, failback if colorama not available
+            self.colorama=False
+            try:
+                import colorama
+                global colorama
+                self.colorama = True
+            except ImportError:
+                pass
+
+        else:
+            self.colorama=False
+
+    def error(self, txt):
+        if self.colorama:
+            print(colorama.Fore.RED + colorama.Style.BRIGHT + "! " + txt + colorama.Style.RESET_ALL, file=sys.stderr)
+        else:
+            print("! " + txt, file=sys.stderr)
+        sys.stderr.flush()
+
+    def warning(self, txt):
+        if self.colorama:
+            print(colorama.Fore.YELLOW + colorama.Style.BRIGHT + "  NOTE: " + txt + colorama.Style.RESET_ALL)
+        else:
+            print("  NOTE: " + txt)
+        sys.stdout.flush()
+
+    def verbose(self, txt):
+        if self.show_verbose:
+            if self.colorama:
+                print(colorama.Style.NORMAL + "  " + txt + colorama.Style.RESET_ALL)
+            else:
+                print("  " + txt)
+            sys.stdout.flush()
+
+    def debug(self, txt):
+        if self.show_debug:
+            if self.colorama:
+                print(colorama.Fore.GREEN + "# " + txt + colorama.Style.RESET_ALL)
+            else:
+                print("# " + txt)
+            sys.stdout.flush()
+
+    def progress(self, txt):
+        """print progress output to stderr (stays on same line)"""
+        self.clear_progress()
+        print(">>> {}\r".format(txt), end='', file=sys.stderr)
+        sys.stderr.flush()
+
+    def clear_progress(self):
+        import colorama
+        print(colorama.ansi.clear_line(), end='', file=sys.stderr)
+        sys.stderr.flush()

zfs_autobackup/LogStub.py

@@ -0,0 +1,18 @@
+#Used for baseclasses that dont implement their own logging (Like ExecuteNode)
+#Usually logging is implemented in subclasses (Like ZfsNode thats a subclass of ExecuteNode), but for regression testing its nice to have these stubs.
+
+class LogStub:
+    """Just a stub, usually overriden in subclasses."""
+
+    # simple logging stubs
+    def debug(self, txt):
+        print("DEBUG  : " + txt)
+
+    def verbose(self, txt):
+        print("VERBOSE: " + txt)
+
+    def warning(self, txt):
+        print("WARNING: " + txt)
+
+    def error(self, txt):
+        print("ERROR  : " + txt)

zfs_autobackup/Thinner.py

@@ -0,0 +1,99 @@
+import time
+
+from zfs_autobackup.ThinnerRule import ThinnerRule
+
+
+class Thinner:
+    """progressive thinner (universal, used for cleaning up snapshots)"""
+
+    def __init__(self, schedule_str=""):
+        """
+        Args:
+            schedule_str: comma seperated list of ThinnerRules. A plain number specifies how many snapshots to always keep.
+        """
+
+        self.rules = []
+        self.always_keep = 0
+
+        if schedule_str == "":
+            return
+
+        rule_strs = schedule_str.split(",")
+        for rule_str in rule_strs:
+            if rule_str.lstrip('-').isdigit():
+                self.always_keep = int(rule_str)
+                if self.always_keep < 0:
+                    raise (Exception("Number of snapshots to keep cant be negative: {}".format(self.always_keep)))
+            else:
+                self.rules.append(ThinnerRule(rule_str))
+
+    def human_rules(self):
+        """get list of human readable rules"""
+        ret = []
+        if self.always_keep:
+            ret.append("Keep the last {} snapshot{}.".format(self.always_keep, self.always_keep != 1 and "s" or ""))
+        for rule in self.rules:
+            ret.append(rule.human_str)
+
+        return ret
+
+    def thin(self, objects, keep_objects=None, now=None):
+        """thin list of objects with current schedule rules. objects: list of
+        objects to thin. every object should have timestamp attribute.
+
+            return( keeps, removes )
+
+        Args:
+            objects: list of objects to check (should have a timestamp attribute)
+            keep_objects: objects to always keep (if they also are in the in the normal objects list)
+            now: if specified, use this time as current time
+        """
+
+        if not keep_objects:
+            keep_objects = []
+
+        # always keep a number of the last objets?
+        if self.always_keep:
+            # all of them
+            if len(objects) <= self.always_keep:
+                return objects, []
+
+            # determine which ones
+            always_keep_objects = objects[-self.always_keep:]
+        else:
+            always_keep_objects = []
+
+        # determine time blocks
+        time_blocks = {}
+        for rule in self.rules:
+            time_blocks[rule.period] = {}
+
+        if not now:
+            now = int(time.time())
+
+        keeps = []
+        removes = []
+
+        # traverse objects
+        for thisobject in objects:
+            # important they are ints!
+            timestamp = int(thisobject.timestamp)
+            age = int(now) - timestamp
+
+            # store in the correct time blocks, per period-size, if not too old yet
+            # e.g.: look if there is ANY timeblock that wants to keep this object
+            keep = False
+            for rule in self.rules:
+                if age <= rule.ttl:
+                    block_nr = int(timestamp / rule.period)
+                    if block_nr not in time_blocks[rule.period]:
+                        time_blocks[rule.period][block_nr] = True
+                        keep = True
+
+            # keep it according to schedule, or keep it because it is in the keep_objects list
+            if keep or thisobject in keep_objects or thisobject in always_keep_objects:
+                keeps.append(thisobject)
+            else:
+                removes.append(thisobject)
+
+        return keeps, removes

zfs_autobackup/ThinnerRule.py

@@ -0,0 +1,71 @@
+import re
+
+
+class ThinnerRule:
+    """a thinning schedule rule for Thinner"""
+
+    TIME_NAMES = {
+        'y': 3600 * 24 * 365.25,
+        'm': 3600 * 24 * 30,
+        'w': 3600 * 24 * 7,
+        'd': 3600 * 24,
+        'h': 3600,
+        'min': 60,
+        's': 1,
+    }
+
+    TIME_DESC = {
+        'y': 'year',
+        'm': 'month',
+        'w': 'week',
+        'd': 'day',
+        'h': 'hour',
+        'min': 'minute',
+        's': 'second',
+    }
+
+    def __init__(self, rule_str):
+        """parse scheduling string
+            example:
+                daily snapshot, remove after a week:     1d1w
+                weekly snapshot, remove after a month:   1w1m
+                monthly snapshot, remove after 6 months: 1m6m
+                yearly snapshot, remove after 2 year:    1y2y
+                keep all snapshots, remove after a day   1s1d
+                keep nothing:                            1s1s
+
+        """
+
+        rule_str = rule_str.lower()
+        matches = re.findall("([0-9]*)([a-z]*)([0-9]*)([a-z]*)", rule_str)[0]
+
+        if '' in matches:
+            raise (Exception("Invalid schedule string: '{}'".format(rule_str)))
+
+        period_amount = int(matches[0])
+        period_unit = matches[1]
+        ttl_amount = int(matches[2])
+        ttl_unit = matches[3]
+
+        if period_unit not in self.TIME_NAMES:
+            raise (Exception("Invalid period string in schedule: '{}'".format(rule_str)))
+
+        if ttl_unit not in self.TIME_NAMES:
+            raise (Exception("Invalid ttl string in schedule: '{}'".format(rule_str)))
+
+        self.period = period_amount * self.TIME_NAMES[period_unit]
+        self.ttl = ttl_amount * self.TIME_NAMES[ttl_unit]
+
+        if self.period > self.ttl:
+            raise (Exception("Period cant be longer than ttl in schedule: '{}'".format(rule_str)))
+
+        self.rule_str = rule_str
+
+        self.human_str = "Keep every {} {}{}, delete after {} {}{}.".format(
+            period_amount, self.TIME_DESC[period_unit], period_amount != 1 and "s" or "", ttl_amount,
+            self.TIME_DESC[ttl_unit], ttl_amount != 1 and "s" or "")
+
+    def __str__(self):
+        """get schedule as a schedule string"""
+
+        return self.rule_str

zfs_autobackup/ZfsAutobackup.py

@@ -0,0 +1,574 @@
+import argparse
+import sys
+import time
+
+from zfs_autobackup import compressors
+from zfs_autobackup.ExecuteNode import ExecuteNode
+from zfs_autobackup.Thinner import Thinner
+from zfs_autobackup.ZfsDataset import ZfsDataset
+from zfs_autobackup.LogConsole import LogConsole
+from zfs_autobackup.ZfsNode import ZfsNode
+from zfs_autobackup.ThinnerRule import ThinnerRule
+
+
+
+
+class ZfsAutobackup:
+    """main class"""
+
+    VERSION = "3.1-rc3"
+    HEADER = "zfs-autobackup v{} - (c)2021 E.H.Eefting (edwin@datux.nl)".format(VERSION)
+
+    def __init__(self, argv, print_arguments=True):
+
+        # helps with investigating failed regression tests:
+        if print_arguments:
+            print("ARGUMENTS: " + " ".join(argv))
+
+        parser = argparse.ArgumentParser(
+            description=self.HEADER,
+            epilog='Full manual at: https://github.com/psy0rz/zfs_autobackup')
+        parser.add_argument('--ssh-config', metavar='CONFIG-FILE', default=None, help='Custom ssh client config')
+        parser.add_argument('--ssh-source', metavar='USER@HOST', default=None,
+                            help='Source host to get backup from.')
+        parser.add_argument('--ssh-target', metavar='USER@HOST', default=None,
+                            help='Target host to push backup to.')
+        parser.add_argument('--keep-source', metavar='SCHEDULE', type=str, default="10,1d1w,1w1m,1m1y",
+                            help='Thinning schedule for old source snapshots. Default: %(default)s')
+        parser.add_argument('--keep-target', metavar='SCHEDULE', type=str, default="10,1d1w,1w1m,1m1y",
+                            help='Thinning schedule for old target snapshots. Default: %(default)s')
+
+        parser.add_argument('backup_name', metavar='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_path', metavar='target-path', default=None, nargs='?',
+                            help='Target ZFS filesystem (optional: if not specified, zfs-autobackup will only operate '
+                                 'as snapshot-tool on source)')
+
+        parser.add_argument('--other-snapshots', action='store_true',
+                            help='Send over other snapshots as well, not just the ones created by this tool.')
+        parser.add_argument('--no-snapshot', action='store_true',
+                            help='Don\'t create new snapshots (useful for finishing uncompleted backups, or cleanups)')
+        parser.add_argument('--no-send', action='store_true',
+                            help='Don\'t send snapshots (useful for cleanups, or if you want a serperate send-cronjob)')
+        parser.add_argument('--no-thinning', action='store_true', help="Do not destroy any snapshots.")
+        parser.add_argument('--no-holds', action='store_true',
+                            help='Don\'t hold snapshots. (Faster. Allows you to destroy common snapshot.)')
+        parser.add_argument('--min-change', metavar='BYTES', type=int, default=1,
+                            help='Number of bytes written after which we consider a dataset changed (default %('
+                                 'default)s)')
+        parser.add_argument('--allow-empty', action='store_true',
+                            help='If nothing has changed, still create empty snapshots. (same as --min-change=0)')
+        parser.add_argument('--ignore-replicated', action='store_true',
+                            help='Ignore datasets that seem to be replicated some other way. (No changes since '
+                                 'lastest snapshot. Useful for proxmox HA replication)')
+
+        parser.add_argument('--strip-path', metavar='N', default=0, type=int,
+                            help='Number of directories to strip from target 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) Will also show nice progress output.')
+
+        parser.add_argument('--clear-refreservation', action='store_true',
+                            help='Filter "refreservation" property. (recommended, safes space. same as '
+                                 '--filter-properties refreservation)')
+        parser.add_argument('--clear-mountpoint', action='store_true',
+                            help='Set property canmount=noauto for new datasets. (recommended, prevents mount '
+                                 'conflicts. same as --set-properties canmount=noauto)')
+        parser.add_argument('--filter-properties', metavar='PROPERY,...', type=str,
+                            help='List of properties to "filter" when receiving filesystems. (you can still restore '
+                                 'them with zfs inherit -S)')
+        parser.add_argument('--set-properties', metavar='PROPERTY=VALUE,...', type=str,
+                            help='List of propererties to override when receiving filesystems. (you can still restore '
+                                 'them with zfs inherit -S)')
+        parser.add_argument('--rollback', action='store_true',
+                            help='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)')
+        parser.add_argument('--destroy-incompatible', action='store_true',
+                            help='Destroy incompatible snapshots on target. Use with care! (implies --rollback)')
+        parser.add_argument('--destroy-missing', metavar="SCHEDULE", type=str, default=None,
+                            help='Destroy datasets on target that are missing on the source. Specify the time since '
+                                 'the last snapshot, e.g: --destroy-missing 30d')
+        parser.add_argument('--ignore-transfer-errors', action='store_true',
+                            help='Ignore transfer errors (still checks if received filesystem exists. useful for '
+                                 'acltype errors)')
+
+        parser.add_argument('--decrypt', action='store_true',
+                            help='Decrypt data before sending it over.')
+
+        parser.add_argument('--encrypt', action='store_true',
+                            help='Encrypt data after receiving it.')
+
+        parser.add_argument('--zfs-compressed', action='store_true',
+                            help='Transfer blocks that already have zfs-compression as-is.')
+
+        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='Show zfs commands that are executed, stops after an exception.')
+        parser.add_argument('--debug-output', action='store_true',
+                            help='Show zfs commands and their output/exit codes. (noisy)')
+        parser.add_argument('--progress', action='store_true',
+                            help='show zfs progress output. Enabled automaticly on ttys. (use --no-progress to disable)')
+        parser.add_argument('--no-progress', action='store_true',
+                            help=argparse.SUPPRESS)  # needed to workaround a zfs recv -v bug
+
+        parser.add_argument('--resume', action='store_true', help=argparse.SUPPRESS)
+        parser.add_argument('--raw', action='store_true', help=argparse.SUPPRESS)
+        parser.add_argument('--exclude-received', action='store_true',
+                            help=argparse.SUPPRESS)  # probably never needed anymore
+
+        #these things all do stuff by piping zfs send/recv IO
+        parser.add_argument('--send-pipe', metavar="COMMAND", default=[], action='append',
+                            help='pipe zfs send output through COMMAND (can be used multiple times)')
+        parser.add_argument('--recv-pipe', metavar="COMMAND", default=[], action='append',
+                            help='pipe zfs recv input through COMMAND (can be used multiple times)')
+        parser.add_argument('--compress', metavar='TYPE', default=None, choices=compressors.choices(), help='Use compression during transfer, zstd-fast recommended. ({})'.format(", ".join(compressors.choices())))
+        parser.add_argument('--rate', metavar='DATARATE', default=None, help='Limit data transfer rate (e.g. 128K. requires mbuffer.)')
+        parser.add_argument('--buffer', metavar='SIZE', default=None, help='Add zfs send and recv buffers to smooth out IO bursts. (e.g. 128M. requires mbuffer)')
+
+
+
+        # note args is the only global variable we use, since its a global readonly setting anyway
+        args = parser.parse_args(argv)
+
+        self.args = args
+
+        # auto enable progress?
+        if sys.stderr.isatty() and not args.no_progress:
+            args.progress = True
+
+        if args.debug_output:
+            args.debug = True
+
+        if self.args.test:
+            self.args.verbose = True
+
+        if args.allow_empty:
+            args.min_change = 0
+
+        if args.destroy_incompatible:
+            args.rollback = True
+
+        self.log = LogConsole(show_debug=self.args.debug, show_verbose=self.args.verbose, color=sys.stdout.isatty())
+        self.verbose(self.HEADER)
+
+        if args.resume:
+            self.warning("The --resume option isn't needed anymore (its autodetected now)")
+
+        if args.raw:
+            self.warning(
+                "The --raw option isn't needed anymore (its autodetected now). Also see --encrypt and --decrypt.")
+
+        if args.target_path is not None and args.target_path[0] == "/":
+            self.log.error("Target should not start with a /")
+            sys.exit(255)
+
+        if args.compress and args.ssh_source is None and args.ssh_target is None:
+            self.warning("Using compression, but transfer is local.")
+
+        if args.compress and args.zfs_compressed:
+            self.warning("Using --compress with --zfs-compress, might be inefficient.")
+
+    def verbose(self, txt):
+        self.log.verbose(txt)
+
+    def warning(self, txt):
+        self.log.warning(txt)
+
+    def error(self, txt):
+        self.log.error(txt)
+
+    def debug(self, txt):
+        self.log.debug(txt)
+
+    def set_title(self, title):
+        self.log.verbose("")
+        self.log.verbose("#### " + title)
+
+    def progress(self, txt):
+        self.log.progress(txt)
+
+    def clear_progress(self):
+        self.log.clear_progress()
+
+    # NOTE: this method also uses self.args. args that need extra processing are passed as function parameters:
+    def thin_missing_targets(self, target_dataset, used_target_datasets):
+        """thin target datasets that are missing on the source."""
+
+        self.debug("Thinning obsolete datasets")
+        missing_datasets = [dataset for dataset in target_dataset.recursive_datasets if
+                            dataset not in used_target_datasets]
+
+        count = 0
+        for dataset in missing_datasets:
+
+            count = count + 1
+            if self.args.progress:
+                self.progress("Analysing missing {}/{}".format(count, len(missing_datasets)))
+
+            try:
+                dataset.debug("Missing on source, thinning")
+                dataset.thin()
+
+            except Exception as e:
+                dataset.error("Error during thinning of missing datasets ({})".format(str(e)))
+
+        if self.args.progress:
+            self.clear_progress()
+
+    # NOTE: this method also uses self.args. args that need extra processing are passed as function parameters:
+    def destroy_missing_targets(self, target_dataset, used_target_datasets):
+        """destroy target datasets that are missing on the source and that meet the requirements"""
+
+        self.debug("Destroying obsolete datasets")
+
+        missing_datasets = [dataset for dataset in target_dataset.recursive_datasets if
+                            dataset not in used_target_datasets]
+
+        count = 0
+        for dataset in missing_datasets:
+
+            count = count + 1
+            if self.args.progress:
+                self.progress("Analysing destroy missing {}/{}".format(count, len(missing_datasets)))
+
+            try:
+                # cant do anything without our own snapshots
+                if not dataset.our_snapshots:
+                    if dataset.datasets:
+                        # its not a leaf, just ignore
+                        dataset.debug("Destroy missing: ignoring")
+                    else:
+                        dataset.verbose(
+                            "Destroy missing: has no snapshots made by us. (please destroy manually)")
+                else:
+                    # past the deadline?
+                    deadline_ttl = ThinnerRule("0s" + self.args.destroy_missing).ttl
+                    now = int(time.time())
+                    if dataset.our_snapshots[-1].timestamp + deadline_ttl > now:
+                        dataset.verbose("Destroy missing: Waiting for deadline.")
+                    else:
+
+                        dataset.debug("Destroy missing: Removing our snapshots.")
+
+                        # remove all our snaphots, except last, to safe space in case we fail later on
+                        for snapshot in dataset.our_snapshots[:-1]:
+                            snapshot.destroy(fail_exception=True)
+
+                        # does it have other snapshots?
+                        has_others = False
+                        for snapshot in dataset.snapshots:
+                            if not snapshot.is_ours():
+                                has_others = True
+                                break
+
+                        if has_others:
+                            dataset.verbose("Destroy missing: Still in use by other snapshots")
+                        else:
+                            if dataset.datasets:
+                                dataset.verbose("Destroy missing: Still has children here.")
+                            else:
+                                dataset.verbose("Destroy missing.")
+                                dataset.our_snapshots[-1].destroy(fail_exception=True)
+                                dataset.destroy(fail_exception=True)
+
+            except Exception as e:
+                dataset.error("Error during --destroy-missing: {}".format(str(e)))
+
+        if self.args.progress:
+            self.clear_progress()
+
+    def get_send_pipes(self, logger):
+        """determine the zfs send pipe"""
+
+        ret=[]
+
+        # IO buffer
+        if self.args.buffer:
+            logger("zfs send buffer        : {}".format(self.args.buffer))
+            ret.extend([ ExecuteNode.PIPE, "mbuffer", "-q", "-s128k", "-m"+self.args.buffer ])
+
+        # custom pipes
+        for send_pipe in self.args.send_pipe:
+            ret.append(ExecuteNode.PIPE)
+            ret.extend(send_pipe.split(" "))
+            logger("zfs send custom pipe   : {}".format(send_pipe))
+
+        # compression
+        if self.args.compress!=None:
+            ret.append(ExecuteNode.PIPE)
+            cmd=compressors.compress_cmd(self.args.compress)
+            ret.extend(cmd)
+            logger("zfs send compression   : {}".format(" ".join(cmd)))
+
+        # transfer rate
+        if self.args.rate:
+            logger("zfs send transfer rate : {}".format(self.args.rate))
+            ret.extend([ ExecuteNode.PIPE, "mbuffer", "-q", "-s128k", "-m16M", "-R"+self.args.rate ])
+
+
+        return ret
+
+    def get_recv_pipes(self, logger):
+
+        ret=[]
+
+        # decompression
+        if self.args.compress!=None:
+            cmd=compressors.decompress_cmd(self.args.compress)
+            ret.extend(cmd)
+            ret.append(ExecuteNode.PIPE)
+            logger("zfs recv decompression : {}".format(" ".join(cmd)))
+
+        # custom pipes
+        for recv_pipe in self.args.recv_pipe:
+            ret.extend(recv_pipe.split(" "))
+            ret.append(ExecuteNode.PIPE)
+            logger("zfs recv custom pipe   : {}".format(recv_pipe))
+
+        # IO buffer
+        if self.args.buffer:
+            #only add second buffer if its usefull. (e.g. non local transfer or other pipes active)
+            if self.args.ssh_source!=None or self.args.ssh_target!=None or self.args.recv_pipe or self.args.send_pipe or self.args.compress!=None:
+                logger("zfs recv buffer        : {}".format(self.args.buffer))
+                ret.extend(["mbuffer", "-q", "-s128k", "-m"+self.args.buffer,  ExecuteNode.PIPE ])
+
+        return ret
+
+    # NOTE: this method also uses self.args. args that need extra processing are passed as function parameters:
+    def sync_datasets(self, source_node, source_datasets, target_node):
+        """Sync datasets, or thin-only on both sides
+        :type target_node: ZfsNode
+        :type source_datasets: list of ZfsDataset
+        :type source_node: ZfsNode
+        """
+
+        send_pipes=self.get_send_pipes(source_node.verbose)
+        recv_pipes=self.get_recv_pipes(target_node.verbose)
+
+        fail_count = 0
+        count = 0
+        target_datasets = []
+        for source_dataset in source_datasets:
+
+            # stats
+            if self.args.progress:
+                count = count + 1
+                self.progress("Analysing dataset {}/{} ({} failed)".format(count, len(source_datasets), fail_count))
+
+            try:
+                # determine corresponding target_dataset
+                target_name = self.args.target_path + "/" + source_dataset.lstrip_path(self.args.strip_path)
+                target_dataset = ZfsDataset(target_node, target_name)
+                target_datasets.append(target_dataset)
+
+                # ensure parents exists
+                # TODO: this isnt perfect yet, in some cases it can create parents when it shouldn't.
+                if not self.args.no_send \
+                        and target_dataset.parent not in target_datasets \
+                        and not target_dataset.parent.exists:
+                    target_dataset.parent.create_filesystem(parents=True)
+
+                # determine common zpool features (cached, so no problem we call it often)
+                source_features = source_node.get_zfs_pool(source_dataset.split_path()[0]).features
+                target_features = target_node.get_zfs_pool(target_dataset.split_path()[0]).features
+                common_features = source_features and target_features
+
+                # sync the snapshots of this dataset
+                source_dataset.sync_snapshots(target_dataset, show_progress=self.args.progress,
+                                              features=common_features, filter_properties=self.filter_properties_list(),
+                                              set_properties=self.set_properties_list(),
+                                              ignore_recv_exit_code=self.args.ignore_transfer_errors,
+                                              holds=not self.args.no_holds, rollback=self.args.rollback,
+                                              also_other_snapshots=self.args.other_snapshots,
+                                              no_send=self.args.no_send,
+                                              destroy_incompatible=self.args.destroy_incompatible,
+                                              send_pipes=send_pipes, recv_pipes=recv_pipes,
+                                              decrypt=self.args.decrypt, encrypt=self.args.encrypt, zfs_compressed=self.args.zfs_compressed )
+            except Exception as e:
+                fail_count = fail_count + 1
+                source_dataset.error("FAILED: " + str(e))
+                if self.args.debug:
+                    raise
+
+        if self.args.progress:
+            self.clear_progress()
+
+        target_path_dataset = ZfsDataset(target_node, self.args.target_path)
+        if not self.args.no_thinning:
+            self.thin_missing_targets(target_dataset=target_path_dataset, used_target_datasets=target_datasets)
+
+        if self.args.destroy_missing is not None:
+            self.destroy_missing_targets(target_dataset=target_path_dataset, used_target_datasets=target_datasets)
+
+        return fail_count
+
+    def thin_source(self, source_datasets):
+
+        self.set_title("Thinning source")
+
+        for source_dataset in source_datasets:
+            source_dataset.thin(skip_holds=True)
+
+    def filter_replicated(self, datasets):
+        if not self.args.ignore_replicated:
+            return datasets
+        else:
+            self.set_title("Filtering already replicated filesystems")
+            ret = []
+            for dataset in datasets:
+                if dataset.is_changed(self.args.min_change):
+                    ret.append(dataset)
+                else:
+                    dataset.verbose("Ignoring, already replicated")
+
+            return ret
+
+    def filter_properties_list(self):
+
+        if self.args.filter_properties:
+            filter_properties = self.args.filter_properties.split(",")
+        else:
+            filter_properties = []
+
+        if self.args.clear_refreservation:
+            filter_properties.append("refreservation")
+
+        return filter_properties
+
+    def set_properties_list(self):
+
+        if self.args.set_properties:
+            set_properties = self.args.set_properties.split(",")
+        else:
+            set_properties = []
+
+        if self.args.clear_mountpoint:
+            set_properties.append("canmount=noauto")
+
+        return set_properties
+
+    def run(self):
+
+        try:
+
+            if self.args.test:
+                self.warning("TEST MODE - SIMULATING WITHOUT MAKING ANY CHANGES")
+
+            ################ create source zfsNode
+            self.set_title("Source settings")
+
+            description = "[Source]"
+            if self.args.no_thinning:
+                source_thinner = None
+            else:
+                source_thinner = Thinner(self.args.keep_source)
+            source_node = ZfsNode(self.args.backup_name, self, ssh_config=self.args.ssh_config,
+                                  ssh_to=self.args.ssh_source, readonly=self.args.test,
+                                  debug_output=self.args.debug_output, description=description, thinner=source_thinner)
+            source_node.verbose(
+                "Selects all datasets that have property 'autobackup:{}=true' (or childs of datasets that have "
+                "'autobackup:{}=child')".format(
+                    self.args.backup_name, self.args.backup_name))
+
+            ################# select source datasets
+            self.set_title("Selecting")
+
+            #Note: Before version v3.1-beta5, we always used exclude_received. This was a problem if you wanto to replicate an existing backup to another host and use the same backupname/snapshots.
+            exclude_paths = []
+            exclude_received=self.args.exclude_received
+            if self.args.ssh_source == self.args.ssh_target:
+                if self.args.target_path:
+                    # target and source are the same, make sure to exclude target_path
+                    self.warning("Source and target are on the same host, excluding target-path from selection.")
+                    exclude_paths.append(self.args.target_path)
+                else:
+                    self.warning("Source and target are on the same host, excluding received datasets from selection.")
+                    exclude_received=True
+
+
+            selected_source_datasets = source_node.selected_datasets(exclude_received=exclude_received,
+                                                                     exclude_paths=exclude_paths)
+            if not selected_source_datasets:
+                self.error(
+                    "No source filesystems selected, please do a 'zfs set autobackup:{0}=true' on the source datasets "
+                    "you want to select.".format(
+                        self.args.backup_name))
+                return 255
+
+            # filter out already replicated stuff?
+            source_datasets = self.filter_replicated(selected_source_datasets)
+
+            ################# snapshotting
+            if not self.args.no_snapshot:
+                self.set_title("Snapshotting")
+                source_node.consistent_snapshot(source_datasets, source_node.new_snapshotname(),
+                                                min_changed_bytes=self.args.min_change)
+
+            ################# sync
+            # if target is specified, we sync the datasets, otherwise we just thin the source. (e.g. snapshot mode)
+            if self.args.target_path:
+
+                # create target_node
+                self.set_title("Target settings")
+                if self.args.no_thinning:
+                    target_thinner = None
+                else:
+                    target_thinner = Thinner(self.args.keep_target)
+                target_node = ZfsNode(self.args.backup_name, self, ssh_config=self.args.ssh_config,
+                                      ssh_to=self.args.ssh_target,
+                                      readonly=self.args.test, debug_output=self.args.debug_output,
+                                      description="[Target]",
+                                      thinner=target_thinner)
+                target_node.verbose("Receive datasets under: {}".format(self.args.target_path))
+
+                self.set_title("Synchronising")
+
+                # check if exists, to prevent vague errors
+                target_dataset = ZfsDataset(target_node, self.args.target_path)
+                if not target_dataset.exists:
+                    raise (Exception(
+                        "Target path '{}' does not exist. Please create this dataset first.".format(target_dataset)))
+
+                # do the actual sync
+                # NOTE: even with no_send, no_thinning and no_snapshot it does a usefull thing because it checks if the common snapshots and shows incompatible snapshots
+                fail_count = self.sync_datasets(
+                    source_node=source_node,
+                    source_datasets=source_datasets,
+                    target_node=target_node)
+
+            # no target specified, run in snapshot-only mode
+            else:
+                if not self.args.no_thinning:
+                    self.thin_source(source_datasets)
+                fail_count = 0
+
+            if not fail_count:
+                if self.args.test:
+                    self.set_title("All tests successful.")
+                else:
+                    self.set_title("All operations completed successfully")
+                    if not self.args.target_path:
+                        self.verbose("(No target_path specified, only operated as snapshot tool.)")
+
+            else:
+                if fail_count != 255:
+                    self.error("{} dataset(s) failed!".format(fail_count))
+
+            if self.args.test:
+                self.verbose("")
+                self.warning("TEST MODE - DID NOT MAKE ANY CHANGES!")
+
+            return fail_count
+
+        except Exception as e:
+            self.error("Exception: " + str(e))
+            if self.args.debug:
+                raise
+            return 255
+        except KeyboardInterrupt:
+            self.error("Aborted")
+            return 255

zfs_autobackup/ZfsNode.py

@@ -0,0 +1,241 @@
+# python 2 compatibility
+from __future__ import print_function
+import re
+import subprocess
+import sys
+import time
+
+from zfs_autobackup.ExecuteNode import ExecuteNode
+from zfs_autobackup.Thinner import Thinner
+from zfs_autobackup.CachedProperty import CachedProperty
+from zfs_autobackup.ZfsPool import ZfsPool
+from zfs_autobackup.ZfsDataset import ZfsDataset
+from zfs_autobackup.ExecuteNode import ExecuteError
+
+
+class ZfsNode(ExecuteNode):
+    """a node that contains zfs datasets. implements global (systemwide/pool wide) zfs commands"""
+
+    def __init__(self, backup_name, logger, ssh_config=None, ssh_to=None, readonly=False, description="",
+                 debug_output=False, thinner=None):
+        self.backup_name = backup_name
+        self.description = description
+
+        self.logger = logger
+
+        if ssh_config:
+            self.verbose("Using custom SSH config: {}".format(ssh_config))
+
+        if ssh_to:
+            self.verbose("Datasets on: {}".format(ssh_to))
+        else:
+            self.verbose("Datasets are local")
+
+        if thinner is not None:
+            rules = thinner.human_rules()
+            if rules:
+                for rule in rules:
+                    self.verbose(rule)
+            else:
+                self.verbose("Keep no old snaphots")
+
+        self.__thinner = thinner
+
+        # list of ZfsPools
+        self.__pools = {}
+
+        self._progress_total_bytes = 0
+        self._progress_start_time = time.time()
+
+        ExecuteNode.__init__(self, ssh_config=ssh_config, ssh_to=ssh_to, readonly=readonly, debug_output=debug_output)
+
+    def thin(self, objects, keep_objects):
+        if self.__thinner is not None:
+            return self.__thinner.thin(objects, keep_objects)
+        else:
+            return ( keep_objects, [] )
+
+    @CachedProperty
+    def supported_send_options(self):
+        """list of supported options, for optimizing sends"""
+        # not every zfs implementation supports them all
+
+        ret = []
+        for option in ["-L", "-e", "-c"]:
+            if self.valid_command(["zfs", "send", option, "zfs_autobackup_option_test"]):
+                ret.append(option)
+        return ret
+
+    @CachedProperty
+    def supported_recv_options(self):
+        """list of supported options"""
+        # not every zfs implementation supports them all
+
+        ret = []
+        for option in ["-s"]:
+            if self.valid_command(["zfs", "recv", option, "zfs_autobackup_option_test"]):
+                ret.append(option)
+        return ret
+
+    def valid_command(self, cmd):
+        """test if a specified zfs options are valid exit code. use this to determine support options"""
+
+        try:
+            self.run(cmd, hide_errors=True, valid_exitcodes=[0, 1])
+        except ExecuteError:
+            return False
+
+        return True
+
+    # TODO: also create a get_zfs_dataset() function that stores all the objects in a dict. This should optimize
+    #  caching a bit and is more consistent.
+    def get_zfs_pool(self, name):
+        """get a ZfsPool() object from specified name. stores objects internally to enable caching"""
+
+        return self.__pools.setdefault(name, ZfsPool(self, name))
+
+    def reset_progress(self):
+        """reset progress output counters"""
+        self._progress_total_bytes = 0
+        self._progress_start_time = time.time()
+
+    def parse_zfs_progress(self, line, hide_errors, prefix):
+        """try to parse progress output of zfs recv -Pv, and don't show it as error to the user """
+
+        # is it progress output?
+        progress_fields = line.rstrip().split("\t")
+
+        if (line.find("nvlist version") == 0 or
+                line.find("resume token contents") == 0 or
+                len(progress_fields) != 1 or
+                line.find("skipping ") == 0 or
+                re.match("send from .*estimated size is ", line)):
+
+            # always output for debugging offcourse
+            self.debug(prefix + line.rstrip())
+
+            # actual useful info
+            if len(progress_fields) >= 3:
+                if progress_fields[0] == 'full' or progress_fields[0] == 'size':
+                    self._progress_total_bytes = int(progress_fields[2])
+                elif progress_fields[0] == 'incremental':
+                    self._progress_total_bytes = int(progress_fields[3])
+                elif progress_fields[1].isnumeric():
+                    bytes_ = int(progress_fields[1])
+                    if self._progress_total_bytes:
+                        percentage = min(100, int(bytes_ * 100 / self._progress_total_bytes))
+                        speed = int(bytes_ / (time.time() - self._progress_start_time) / (1024 * 1024))
+                        bytes_left = self._progress_total_bytes - bytes_
+                        minutes_left = int((bytes_left / (bytes_ / (time.time() - self._progress_start_time))) / 60)
+
+                        self.logger.progress("Transfer {}% {}MB/s (total {}MB, {} minutes left)".format(percentage, speed, int(
+                            self._progress_total_bytes / (1024 * 1024)), minutes_left))
+
+            return
+
+        # still do the normal stderr output handling
+        if hide_errors:
+            self.debug(prefix + line.rstrip())
+        else:
+            self.error(prefix + line.rstrip())
+
+    # def _parse_stderr_pipe(self, line, hide_errors):
+    #     self.parse_zfs_progress(line, hide_errors, "STDERR|> ")
+
+    def _parse_stderr(self, line, hide_errors):
+        self.parse_zfs_progress(line, hide_errors, "STDERR > ")
+
+    def verbose(self, txt):
+        self.logger.verbose("{} {}".format(self.description, txt))
+
+    def error(self, txt):
+        self.logger.error("{} {}".format(self.description, txt))
+
+    def warning(self, txt):
+        self.logger.warning("{} {}".format(self.description, txt))
+
+    def debug(self, txt):
+        self.logger.debug("{} {}".format(self.description, txt))
+
+    def new_snapshotname(self):
+        """determine uniq new snapshotname"""
+        return self.backup_name + "-" + time.strftime("%Y%m%d%H%M%S")
+
+    def consistent_snapshot(self, datasets, snapshot_name, min_changed_bytes):
+        """create a consistent (atomic) snapshot of specified datasets, per pool.
+        """
+
+        pools = {}
+
+        # collect snapshots that we want to make, per pool
+        # self.debug(datasets)
+        for dataset in datasets:
+            if not dataset.is_changed_ours(min_changed_bytes):
+                dataset.verbose("No changes since {}".format(dataset.our_snapshots[-1].snapshot_name))
+                continue
+
+            # force_exist, since we're making it
+            snapshot = ZfsDataset(dataset.zfs_node, dataset.name + "@" + snapshot_name, force_exists=True)
+
+            pool = dataset.split_path()[0]
+            if pool not in pools:
+                pools[pool] = []
+
+            pools[pool].append(snapshot)
+
+            # update cache, but try to prevent an unneeded zfs list
+            if self.readonly or CachedProperty.is_cached(dataset, 'snapshots'):
+                dataset.snapshots.append(snapshot)  # NOTE: this will trigger zfs list if its not cached
+
+        if not pools:
+            self.verbose("No changes anywhere: not creating snapshots.")
+            return
+
+        # create consistent snapshot per pool
+        for (pool_name, snapshots) in pools.items():
+            cmd = ["zfs", "snapshot"]
+
+            cmd.extend(map(lambda snapshot_: str(snapshot_), snapshots))
+
+            self.verbose("Creating snapshots {} in pool {}".format(snapshot_name, pool_name))
+            self.run(cmd, readonly=False)
+
+    def selected_datasets(self, exclude_received, exclude_paths):
+        """determine filesystems that should be backupped by looking at the special autobackup-property, systemwide
+
+           returns: list of ZfsDataset
+        """
+
+        self.debug("Getting selected datasets")
+
+        # get all source filesystems that have the backup property
+        lines = self.run(tab_split=True, readonly=True, cmd=[
+            "zfs", "get", "-t", "volume,filesystem", "-o", "name,value,source", "-H",
+            "autobackup:" + self.backup_name
+        ])
+
+        # The returnlist of selected ZfsDataset's:
+        selected_filesystems = []
+
+        # list of sources, used to resolve inherited sources
+        sources = {}
+
+        for line in lines:
+            (name, value, raw_source) = line
+            dataset = ZfsDataset(self, name)
+
+            # "resolve" inherited sources
+            sources[name] = raw_source
+            if raw_source.find("inherited from ") == 0:
+                inherited = True
+                inherited_from = re.sub("^inherited from ", "", raw_source)
+                source = sources[inherited_from]
+            else:
+                inherited = False
+                source = raw_source
+
+            # determine it
+            if dataset.is_selected(value=value, source=source, inherited=inherited, exclude_received=exclude_received, exclude_paths=exclude_paths):
+                selected_filesystems.append(dataset)
+
+        return selected_filesystems

zfs_autobackup/ZfsPool.py

@@ -0,0 +1,63 @@
+from zfs_autobackup.CachedProperty import CachedProperty
+
+
+class ZfsPool():
+    """a zfs pool"""
+
+    def __init__(self, zfs_node, name):
+        """name: name of the pool
+        """
+
+        self.zfs_node = zfs_node
+        self.name = name
+
+    def __repr__(self):
+        return "{}: {}".format(self.zfs_node, self.name)
+
+    def __str__(self):
+        return self.name
+
+    def __eq__(self, obj):
+        if not isinstance(obj, ZfsPool):
+            return False
+
+        return self.name == obj.name
+
+    def verbose(self, txt):
+        self.zfs_node.verbose("zpool {}: {}".format(self.name, txt))
+
+    def error(self, txt):
+        self.zfs_node.error("zpool {}: {}".format(self.name, txt))
+
+    def debug(self, txt):
+        self.zfs_node.debug("zpool {}: {}".format(self.name, txt))
+
+    @CachedProperty
+    def properties(self):
+        """all zpool properties"""
+
+        self.debug("Getting zpool properties")
+
+        cmd = [
+            "zpool", "get", "-H", "-p", "all", self.name
+        ]
+
+        ret = {}
+
+        for pair in self.zfs_node.run(tab_split=True, cmd=cmd, readonly=True, valid_exitcodes=[0]):
+            ret[pair[1]] = pair[2]
+
+        return ret
+
+    @property
+    def features(self):
+        """get list of active zpool features"""
+
+        ret = []
+        for (key, value) in self.properties.items():
+            if key.startswith("feature@"):
+                feature = key.split("@")[1]
+                if value == 'enabled' or value == 'active':
+                    ret.append(feature)
+
+        return ret

zfs_autobackup/__init__.py

@@ -0,0 +1,9 @@
+
+
+
+def cli():
+    import sys
+    from zfs_autobackup.ZfsAutobackup import ZfsAutobackup
+
+    zfs_autobackup = ZfsAutobackup(sys.argv[1:], False)
+    sys.exit(zfs_autobackup.run())

zfs_autobackup/__main__.py

@@ -0,0 +1,10 @@
+# (c)edwin@datux.nl  - Released under GPL V3
+#
+# Greetings from eth0 2019 :)
+
+import sys
+
+if __name__ == "__main__":
+    from . import cli
+    cli()
+

zfs_autobackup/compressors.py

@@ -0,0 +1,69 @@
+# Adopted from Syncoid :)
+
+# this software is licensed for use under the Free Software Foundation's GPL v3.0 license, as retrieved
+# from http://www.gnu.org/licenses/gpl-3.0.html on 2014-11-17.  A copy should also be available in this
+# project's Git repository at https://github.com/jimsalterjrs/sanoid/blob/master/LICENSE.
+
+COMPRESS_CMDS = {
+    'gzip': {
+        'cmd': 'gzip',
+        'args': [ '-3' ],
+        'dcmd': 'zcat',
+        'dargs': [],
+    },
+    'pigz-fast': {
+        'cmd': 'pigz',
+        'args': [ '-3' ],
+        'dcmd': 'pigz',
+        'dargs': [ '-dc' ],
+    },
+    'pigz-slow': {
+        'cmd': 'pigz',
+        'args': [ '-9' ],
+        'dcmd': 'pigz',
+        'dargs': [ '-dc' ],
+    },
+    'zstd-fast': {
+        'cmd': 'zstdmt',
+        'args': [ '-3' ],
+        'dcmd': 'zstdmt',
+        'dargs': [ '-dc' ],
+    },
+    'zstd-slow': {
+        'cmd': 'zstdmt',
+        'args': [ '-19' ],
+        'dcmd': 'zstdmt',
+        'dargs': [ '-dc' ],
+    },
+    'xz': {
+        'cmd': 'xz',
+        'args': [],
+        'dcmd': 'xz',
+        'dargs': [ '-d' ],
+    },
+    'lzo': {
+        'cmd': 'lzop',
+        'args': [],
+        'dcmd': 'lzop',
+        'dargs': [ '-dfc' ],
+    },
+    'lz4': {
+        'cmd': 'lz4',
+        'args': [],
+        'dcmd': 'lz4',
+        'dargs': [ '-dc' ],
+    },
+}
+
+def compress_cmd(compressor):
+    ret=[ COMPRESS_CMDS[compressor]['cmd'] ]
+    ret.extend( COMPRESS_CMDS[compressor]['args'])
+    return ret
+
+def decompress_cmd(compressor):
+    ret= [ COMPRESS_CMDS[compressor]['dcmd'] ]
+    ret.extend(COMPRESS_CMDS[compressor]['dargs'])
+    return ret
+
+def choices():
+    return COMPRESS_CMDS.keys()