Lock version of Docker Credential Helper in CI

add aws secret handling (#161 )
* add aws secret handling * make it look go-ish * fix tests * whitespace * sleep a bit
2025-12-05 17:18:02 +01:00 · 2022-10-12 20:23:40 +02:00 · 2022-10-12 19:14:57 +02:00 · 2022-09-15 10:49:45 +02:00 · 2022-09-15 10:04:12 +02:00 · 2022-09-02 09:39:55 +02:00
64 changed files with 2267 additions and 1304 deletions
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -5,6 +5,7 @@ jobs:
    machine:
      image: ubuntu-2004:202201-02
    working_directory: ~/docker-volume-backup
+    resource_class: large
    steps:
      - checkout
      - run:
@@ -29,11 +30,13 @@ jobs:
          DOCKER_BUILDKIT: '1'
          DOCKER_CLI_EXPERIMENTAL: enabled
    working_directory: ~/docker-volume-backup
+    resource_class: large
    steps:
      - checkout
      - setup_remote_docker:
          version: 20.10.6
-      - docker/install-docker-credential-helper
+      - docker/install-docker-credential-helper:
+          release-tag: v0.6.4
      - docker/configure-docker-credentials-store
      - run:
          name: Push to Docker Hub
@@ -48,6 +51,7 @@ jobs:
            if [[ "$CIRCLE_TAG" =~ ^v[0-9]+\.[0-9]+\.[0-9]+$ ]]; then
              # prerelease tags like `v2.0.0-alpha.1` should not be released as `latest`
              tag_args="$tag_args -t offen/docker-volume-backup:latest"
+              tag_args="$tag_args -t offen/docker-volume-backup:$(echo "$CIRCLE_TAG" | cut -d. -f1)"
            fi
            docker buildx build --platform linux/amd64,linux/arm64,linux/arm/v7 \
               $tag_args . --push
@@ -68,4 +72,4 @@ workflows:
              only: /^v.*/

 orbs:
-  docker: circleci/docker@1.0.1
+  docker: circleci/docker@2.1.4
--- a/.dockerignore
+++ b/.dockerignore
@@ -1 +1,7 @@
 test
+.github
+.circleci
+docs
+.editorconfig
+LICENSE
+README.md
--- a/.github/FUNDING.yml
+++ b/.github/FUNDING.yml
@@ -0,0 +1,3 @@
+github: offen
+patreon: offen
+
--- a/.github/ISSUE_TEMPLATE.md
+++ b/.github/ISSUE_TEMPLATE.md
@@ -1,20 +0,0 @@
-* **I'm submitting a ...**
-  - [ ] bug report
-  - [ ] feature request
-  - [ ] support request
-
-* **What is the current behavior?**
-
-* **If the current behavior is a bug, please provide the configuration and steps to reproduce and if possible a minimal demo of the problem.**
-
-* **What is the expected behavior?**
-
-* **What is the motivation / use case for changing the behavior?**
-
-* **Please tell us about your environment:**
-  
-  - Image version:
-  - Docker version: 
-  - docker-compose version:
-
-* **Other information** (e.g. detailed explanation, stacktraces, related issues, suggestions how to fix, links for us to have context, eg. stackoverflow, etc)
--- a/.github/ISSUE_TEMPLATE/bug_report.md
+++ b/.github/ISSUE_TEMPLATE/bug_report.md
@@ -0,0 +1,28 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+Steps to reproduce the behavior:
+1. ...
+2. ...
+3. ...
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Desktop (please complete the following information):**
+ - Image Version: [e.g. v2.21.0]
+ - Docker Version: [e.g. 20.10.17]
+ - Docker Compose Version (if applicable): [e.g. 1.29.2]
+
+**Additional context**
+Add any other context about the problem here.
--- a/.github/ISSUE_TEMPLATE/feature_request.md
+++ b/.github/ISSUE_TEMPLATE/feature_request.md
@@ -0,0 +1,20 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+**Describe the solution you'd like**
+A clear and concise description of what you want to happen.
+
+**Describe alternatives you've considered**
+A clear and concise description of any alternative solutions or features you've considered.
+
+**Additional context**
+Add any other context or screenshots about the feature request here.
--- a/.github/ISSUE_TEMPLATE/support_request.md
+++ b/.github/ISSUE_TEMPLATE/support_request.md
@@ -0,0 +1,20 @@
+---
+name: Support request
+about: Ask for help
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**What are you trying to do?**
+A clear and concise description of what you are trying to do, but cannot get working.
+
+**What is your current configuration?**
+Add the full configuration you are using. Please redact out any real-world credentials.
+
+**Log output**
+Provide the full log output of your setup.
+
+**Additional context**
+Add any other context or screenshots about the support request here.
--- a/7
+++ b/7
@@ -1,16 +1,15 @@
 # Copyright 2021 - Offen Authors <hioffen@posteo.de>
 # SPDX-License-Identifier: MPL-2.0

-FROM golang:1.17-alpine as builder
+FROM golang:1.19-alpine as builder

 WORKDIR /app
-COPY go.mod go.sum ./
+COPY . .
 RUN go mod download
-COPY cmd/backup ./cmd/backup/
 WORKDIR /app/cmd/backup
 RUN go build -o backup .

-FROM alpine:3.15
+FROM alpine:3.16

 WORKDIR /root

--- a/README.md
+++ b/README.md
@@ -7,7 +7,7 @@
 Backup Docker volumes locally or to any S3 compatible storage.

 The [offen/docker-volume-backup](https://hub.docker.com/r/offen/docker-volume-backup) Docker image can be used as a lightweight (below 15MB) sidecar container to an existing Docker setup.
-It handles __recurring or one-off backups of Docker volumes__ to a __local directory__, __any S3 or WebDAV compatible storage (or any combination) and rotates away old backups__ if configured. It also supports __encrypting your backups using GPG__ and __sending notifications for failed backup runs__.
+It handles __recurring or one-off backups of Docker volumes__ to a __local directory__, __any S3, WebDAV or SSH compatible storage (or any combination) and rotates away old backups__ if configured. It also supports __encrypting your backups using GPG__ and __sending notifications for failed backup runs__.

 <!-- MarkdownTOC -->

@@ -20,20 +20,25 @@ It handles __recurring or one-off backups of Docker volumes__ to a __local direc
  - [Automatically pruning old backups](#automatically-pruning-old-backups)
  - [Send email notifications on failed backup runs](#send-email-notifications-on-failed-backup-runs)
  - [Customize notifications](#customize-notifications)
-  - [Run custom commands before / after backup](#run-custom-commands-before--after-backup)
+  - [Run custom commands during the backup lifecycle](#run-custom-commands-during-the-backup-lifecycle)
  - [Encrypting your backup using GPG](#encrypting-your-backup-using-gpg)
  - [Restoring a volume from a backup](#restoring-a-volume-from-a-backup)
  - [Set the timezone the container runs in](#set-the-timezone-the-container-runs-in)
  - [Using with Docker Swarm](#using-with-docker-swarm)
  - [Manually triggering a backup](#manually-triggering-a-backup)
  - [Update deprecated email configuration](#update-deprecated-email-configuration)
+  - [Replace deprecated `BACKUP_FROM_SNAPSHOT` usage](#replace-deprecated-backup_from_snapshot-usage)
+  - [Replace deprecated `exec-pre` and `exec-post` labels](#replace-deprecated-exec-pre-and-exec-post-labels)
  - [Using a custom Docker host](#using-a-custom-docker-host)
  - [Run multiple backup schedules in the same container](#run-multiple-backup-schedules-in-the-same-container)
+  - [Define different retention schedules](#define-different-retention-schedules)
+  - [Use special characters in notification URLs](#use-special-characters-in-notification-urls)
 - [Recipes](#recipes)
  - [Backing up to AWS S3](#backing-up-to-aws-s3)
  - [Backing up to Filebase](#backing-up-to-filebase)
  - [Backing up to MinIO](#backing-up-to-minio)
  - [Backing up to WebDAV](#backing-up-to-webdav)
+  - [Backing up to SSH](#backing-up-to-ssh)
  - [Backing up locally](#backing-up-locally)
  - [Backing up to AWS S3 as well as locally](#backing-up-to-aws-s3-as-well-as-locally)
  - [Running on a custom cron schedule](#running-on-a-custom-cron-schedule)
@@ -107,7 +112,7 @@ docker run --rm \
  --env AWS_SECRET_ACCESS_KEY="<xxx>" \
  --env AWS_S3_BUCKET_NAME="<xxx>" \
  --entrypoint backup \
-  offen/docker-volume-backup:latest
+  offen/docker-volume-backup:v2
 ```

 Alternatively, pass a `--env-file` in order to use a full config as described below.
@@ -149,6 +154,11 @@ You can populate below template according to your requirements and use it as you

 # BACKUP_LATEST_SYMLINK="backup.latest.tar.gz"

+# ************************************************************************
+# The BACKUP_FROM_SNAPSHOT option has been deprecated and will be removed
+# in the next major version. Please use exec-pre and exec-post
+# as documented below instead.
+# ************************************************************************
 # Whether to copy the content of backup folder before creating the tar archive.
 # In the rare scenario where the content of the source backup volume is continously
 # updating, but we do not wish to stop the container while performing the backup,
@@ -156,6 +166,17 @@ You can populate below template according to your requirements and use it as you

 # BACKUP_FROM_SNAPSHOT="false"

+# By default, the `/backup` directory inside the container will be backed up.
+# In case you need to use a custom location, set `BACKUP_SOURCES`.
+
+# BACKUP_SOURCES="/other/location"
+
+# When given, all files in BACKUP_SOURCES whose full path matches the given
+# regular expression will be excluded from the archive. Regular Expressions
+# can be used as from the Go standard library https://pkg.go.dev/regexp
+
+# BACKUP_EXCLUDE_REGEXP="\.log$"
+
 ########### BACKUP STORAGE

 # The name of the remote bucket that should be used for storing backups. If
@@ -175,6 +196,14 @@ You can populate below template according to your requirements and use it as you
 # AWS_ACCESS_KEY_ID="<xxx>"
 # AWS_SECRET_ACCESS_KEY="<xxx>"

+# It is possible to provide the keys in files, allowing to hide the sensitive data.
+# These values have a higher priority than the ones above, meaning if both are set
+# the values from the files will be used.
+# This option is most useful with Docker [secrets](https://docs.docker.com/engine/swarm/secrets/).
+
+# AWS_ACCESS_KEY_ID_FILE="/path/to/file"
+# AWS_SECRET_ACCESS_KEY_FILE="/path/to/file"
+
 # Instead of providing static credentials, you can also use IAM instance profiles
 # or similar to provide authentication. Some possible configuration options on AWS:
 # - EC2: http://169.254.169.254
@@ -196,12 +225,17 @@ You can populate below template according to your requirements and use it as you
 # AWS_ENDPOINT_PROTO="https"

 # Setting this variable to `true` will disable verification of
-# SSL certificates. You shouldn't use this unless you use self-signed
-# certificates for your remote storage backend. This can only be used
-# when AWS_ENDPOINT_PROTO is set to `https`.
+# SSL certificates for AWS_ENDPOINT. You shouldn't use this unless you use
+# self-signed certificates for your remote storage backend. This can only be
+# used when AWS_ENDPOINT_PROTO is set to `https`.

 # AWS_ENDPOINT_INSECURE="true"

+# Setting this variable will change the S3 storage class header.
+# Defaults to "STANDARD", you can set this value according to your needs.
+
+# AWS_STORAGE_CLASS="GLACIER"
+
 # You can also backup files to any WebDAV server:

 # The URL of the remote WebDAV server
@@ -221,6 +255,46 @@ You can populate below template according to your requirements and use it as you

 # WEBDAV_PASSWORD="password"

+# Setting this variable to `true` will disable verification of
+# SSL certificates for WEBDAV_URL. You shouldn't use this unless you use
+# self-signed certificates for your remote storage backend.
+
+# WEBDAV_URL_INSECURE="true"
+
+# You can also backup files to any SSH server:
+
+# The URL of the remote SSH server
+
+# SSH_HOST_NAME="server.local"
+
+# The port of the remote SSH server
+# Optional variable default value is `22`
+
+# SSH_PORT=2222
+
+# The Directory to place the backups to on the SSH server.
+
+# SSH_REMOTE_PATH="/my/directory/"
+
+# The username for the SSH server
+
+# SSH_USER="user"
+
+# The password for the SSH server
+
+# SSH_PASSWORD="password"
+
+# The private key path in container for SSH server
+# Default value: /root/.ssh/id_rsa
+# If file is mounted to /root/.ssh/id_rsa path it will be used. Non-RSA keys will
+# also work.
+
+# SSH_IDENTITY_FILE="/root/.ssh/id_rsa"
+
+# The passphrase for the identity file
+
+# SSH_IDENTITY_PASSPHRASE="pass"
+
 # In addition to storing backups remotely, you can also keep local copies.
 # Pass a container-local path to store your backups if needed. You also need to
 # mount a local folder or Docker volume into that location (`/archive`
@@ -286,7 +360,7 @@ You can populate below template according to your requirements and use it as you

 # It is possible to define commands to be run in any container before and after
 # a backup is conducted. The commands themselves are defined in labels like
-# `docker-volume-backup.exec-pre=/bin/sh -c 'mysqldump [options] > dump.sql'.
+# `docker-volume-backup.archive-pre=/bin/sh -c 'mysqldump [options] > dump.sql'.
 # Several options exist for controlling this feature:

 # By default, any output of such a command is suppressed. If this value
@@ -330,6 +404,16 @@ You can populate below template according to your requirements and use it as you

 # DOCKER_HOST="tcp://docker_socket_proxy:2375"

+########### LOCK_TIMEOUT
+
+# In the case of overlapping cron schedules run by the same container,
+# subsequent invocations will wait for previous runs to finish before starting.
+# By default, this will time out and fail in case the lock could not be acquired
+# after 60 minutes. In case you need to adjust this timeout, supply a duration
+# value as per https://pkg.go.dev/time#ParseDuration to `LOCK_TIMEOUT`
+
+# LOCK_TIMEOUT="60m"
+
 ########### EMAIL NOTIFICATIONS

 # ************************************************************************
@@ -361,7 +445,7 @@ You can populate below template according to your requirements and use it as you
 # EMAIL_SMTP_PORT="<port>"
 ```

-In case you encouter double quoted values in your configuration you might be running an [older version of `docker-compose`].
+In case you encouter double quoted values in your configuration you might be running an [older version of `docker-compose`][compose-issue].
 You can work around this by either updating `docker-compose` or unquoting your configuration values.

 [compose-issue]: https://github.com/docker/compose/issues/2854
@@ -386,7 +470,7 @@ services:
      - docker-volume-backup.stop-during-backup=service1

  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
      BACKUP_STOP_CONTAINER_LABEL: service1
    volumes:
@@ -409,7 +493,7 @@ version: '3'
 services:
  # ... define other services using the `data` volume here
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
      BACKUP_FILENAME: backup-%Y-%m-%dT%H-%M-%S.tar.gz
      BACKUP_PRUNING_PREFIX: backup-
@@ -432,7 +516,7 @@ version: '3'

 services:
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
      # ... other configuration values go here
      NOTIFICATION_URLS=smtp://me:secret@smtp.example.com:587/?fromAddress=no-reply@example.com&toAddresses=you@example.com
@@ -468,11 +552,16 @@ Overridable template names are: `title_success`, `body_success`, `title_failure`

 For a full list of available variables and functions, see [this page](https://github.com/offen/docker-volume-backup/blob/master/docs/NOTIFICATION-TEMPLATES.md).

-### Run custom commands before / after backup
+### Run custom commands during the backup lifecycle

 In certain scenarios it can be required to run specific commands before and after a backup is taken (e.g. dumping a database).
-When mounting the Docker socket into the `docker-volume-backup` container, you can define pre- and post-commands that will be run in the context of the target container.
-Such commands are defined by specifying the command in a `docker-volume-backup.exec-[pre|post]` label.
+When mounting the Docker socket into the `docker-volume-backup` container, you can define pre- and post-commands that will be run in the context of the target container (it is also possible to run commands inside the `docker-volume-backup` container itself using this feature).
+Such commands are defined by specifying the command in a `docker-volume-backup.[step]-[pre|post]` label where `step` can be any of the following phases of a backup lifecyle:
+
+- `archive` (the tar archive is created)
+- `process` (the tar archive is processed, e.g. encrypted - optional)
+- `copy` (the tar archive is copied to all configured storages)
+- `prune` (existing backups are pruned based on the defined ruleset - optional)

 Taking a database dump using `mysqldump` would look like this:

@@ -486,7 +575,7 @@ services:
    volumes:
      - backup_data:/tmp/backups
    labels:
-      - docker-volume-backup.exec-pre=/bin/sh -c 'mysqldump --all-databases > /backups/dump.sql'
+      - docker-volume-backup.archive-pre=/bin/sh -c 'mysqldump --all-databases > /backups/dump.sql'

 volumes:
  backup_data:
@@ -506,11 +595,11 @@ services:
    volumes:
      - backup_data:/tmp/backups
    labels:
-      - docker-volume-backup.exec-pre=/bin/sh -c 'mysqldump --all-databases > /tmp/volume/dump.sql'
+      - docker-volume-backup.archive-pre=/bin/sh -c 'mysqldump --all-databases > /tmp/volume/dump.sql'
      - docker-volume-backup.exec-label=database

  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
      EXEC_LABEL: database
    volumes:
@@ -522,7 +611,7 @@ volumes:
 ```


-The backup procedure is guaranteed to wait for all `pre` commands to finish.
+The backup procedure is guaranteed to wait for all `pre` or `post` commands to finish before proceeding.
 However there are no guarantees about the order in which they are run, which could also happen concurrently.

 ### Encrypting your backup using GPG
@@ -587,7 +676,7 @@ version: '3'

 services:
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    volumes:
      - data:/backup/my-app-backup:ro
      - /etc/timezone:/etc/timezone:ro
@@ -610,7 +699,7 @@ When running in Swarm mode, it's also advised to set a hard memory limit on your
 ```yml
 services:
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    deployment:
      resources:
        limits:
@@ -645,6 +734,54 @@ After:
 NOTIFICATION_URLS=smtp://me:secret@posteo.de:587/?fromAddress=no-reply@example.com&toAddresses=you@example.com
 ```

+### Replace deprecated `BACKUP_FROM_SNAPSHOT` usage
+
+Starting with version 2.15.0, the `BACKUP_FROM_SNAPSHOT` feature has been deprecated.
+If you need to prepare your sources before the backup is taken, use `archive-pre`, `archive-post` and an intermediate volume:
+
+```yml
+version: '3'
+
+services:
+  my_app:
+    build: .
+    volumes:
+      - data:/var/my_app
+      - backup:/tmp/backup
+    labels:
+      - docker-volume-backup.archive-pre=cp -r /var/my_app /tmp/backup/my-app
+      - docker-volume-backup.archive-post=rm -rf /tmp/backup/my-app
+
+  backup:
+    image: offen/docker-volume-backup:latest
+    environment:
+      BACKUP_SOURCES: /tmp/backup
+    volumes:
+      - backup:/backup:ro
+      - /var/run/docker.sock:/var/run/docker.sock:ro
+
+volumes:
+  data:
+  backup:
+```
+
+### Replace deprecated `exec-pre` and `exec-post` labels
+
+Version 2.19.0 introduced the option to run labeled commands at multiple points in time during the backup lifecycle.
+In order to be able to use more obvious terminology in the new labels, the existing `exec-pre` and `exec-post` labels have been deprecated.
+If you want to emulate the existing behavior, all you need to do is change `exec-pre` to `archive-pre` and `exec-post` to `archive-post`:
+
+```diff
+    labels:
+-     - docker-volume-backup.exec-pre=cp -r /var/my_app /tmp/backup/my-app
+     - docker-volume-backup.archive-pre=cp -r /var/my_app /tmp/backup/my-app
+-     - docker-volume-backup.exec-post=rm -rf /tmp/backup/my-app
+     - docker-volume-backup.archive-post=rm -rf /tmp/backup/my-app
+```
+
+The `EXEC_LABEL` setting and the `docker-volume-backup.exec-label` label stay as is.
+Check the additional documentation on running commands during the backup lifecycle to find out about further possibilities.
+
 ### Using a custom Docker host

 If you are interfacing with Docker via TCP, set `DOCKER_HOST` to the correct URL.
@@ -658,13 +795,13 @@ In case you are using a socket proxy, it must support `GET` and `POST` requests

 Multiple backup schedules with different configuration can be configured by mounting an arbitrary number of configuration files (using the `.env` format) into `/etc/dockervolumebackup/conf.d`:

-```
+```yml
 version: '3'

 services:
  # ... define other services using the `data` volume here
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    volumes:
      - data:/backup/my-app-backup:ro
      - /var/run/docker.sock:/var/run/docker.sock:ro
@@ -676,10 +813,79 @@ volumes:

 A separate cronjob will be created for each config file.
 If a configuration value is set both in the global environment as well as in the config file, the config file will take precedence.
-The `backup` command expects to run on an exclusive lock, so it is your responsibility to make sure the invocations do not overlap.
+The `backup` command expects to run on an exclusive lock, so in case you provide the same or overlapping schedules in your cron expressions, the runs will still be executed serially, one after the other.
+The exact order of schedules that use the same cron expression is not specified.
 In case you need your schedules to overlap, you need to create a dedicated container for each schedule instead.
 When changing the configuration, you currently need to manually restart the container for the changes to take effect.

+Set `BACKUP_SOURCES` for each config file to control which subset of volume mounts gets backed up:
+
+```yml
+# With a volume configuration like this:
+volumes:
+  - /var/run/docker.sock:/var/run/docker.sock:ro
+  - ./configuration:/etc/dockervolumebackup/conf.d
+  - app1_data:/backup/app1_data:ro
+  - app2_data:/backup/app2_data:ro
+```
+
+```ini
+# In the 1st config file:
+BACKUP_SOURCES=/backup/app1_data
+
+# In the 2nd config file:
+BACKUP_SOURCES=/backup/app2_data
+```
+
+### Define different retention schedules
+
+If you want to manage backup retention on different schedules, the most straight forward approach is to define a dedicated configuration for retention rule using a different prefix in the `BACKUP_FILENAME` parameter and then run them on different cron schedules.
+
+For example, if you wanted to keep daily backups for 7 days, weekly backups for a month, and retain monthly backups forever, you could create three configuration files and mount them into `/etc/dockervolumebackup.d`:
+
+```ini
+# 01daily.conf
+BACKUP_FILENAME="daily-backup-%Y-%m-%dT%H-%M-%S.tar.gz"
+# run every day at 2am
+BACKUP_CRON_EXPRESSION="0 2 * * *"
+BACKUP_PRUNING_PREFIX="daily-backup-"
+BACKUP_RETENTION_DAYS="7"
+```
+
+```ini
+# 02weekly.conf
+BACKUP_FILENAME="weekly-backup-%Y-%m-%dT%H-%M-%S.tar.gz"
+# run every monday at 3am
+BACKUP_CRON_EXPRESSION="0 3 * * 1"
+BACKUP_PRUNING_PREFIX="weekly-backup-"
+BACKUP_RETENTION_DAYS="31"
+```
+
+```ini
+# 03monthly.conf
+BACKUP_FILENAME="monthly-backup-%Y-%m-%dT%H-%M-%S.tar.gz"
+# run every 1st of a month at 4am
+BACKUP_CRON_EXPRESSION="0 4 1 * *"
+```
+
+Note that while it's possible to define colliding cron schedules for each of these configurations, you might need to adjust the value for `LOCK_TIMEOUT` in case your backups are large and might take longer than an hour.
+
+### Use special characters in notification URLs
+
+The value given to `NOTIFICATION_URLS` is a comma separated list of URLs.
+If such a URL contains special characters (e.g. commas) it needs to be URL encoded.
+To get an encoded version of your URL, you can use the CLI tool provided by `shoutrrr` (which is the library used for sending notifications):
+
+```
+docker run --rm -ti containrrr/shoutrrr generate [service]
+```
+
+where service is any of the [supported services][shoutrrr-docs], e.g. for SMTP:
+
+```
+docker run --rm -ti containrrr/shoutrrr generate smtp
+```
+
 ## Recipes

 This section lists configuration for some real-world use cases that you can mix and match according to your needs.
@@ -692,9 +898,9 @@ version: '3'
 services:
  # ... define other services using the `data` volume here
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
-      AWS_BUCKET_NAME: backup-bucket
+      AWS_S3_BUCKET_NAME: backup-bucket
      AWS_ACCESS_KEY_ID: AKIAIOSFODNN7EXAMPLE
      AWS_SECRET_ACCESS_KEY: wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
    volumes:
@@ -713,10 +919,10 @@ version: '3'
 services:
  # ... define other services using the `data` volume here
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
      AWS_ENDPOINT: s3.filebase.com
-      AWS_BUCKET_NAME: filebase-bucket
+      AWS_S3_BUCKET_NAME: filebase-bucket
      AWS_ACCESS_KEY_ID: FILEBASE-ACCESS-KEY
      AWS_SECRET_ACCESS_KEY: FILEBASE-SECRET-KEY
    volumes:
@@ -735,10 +941,10 @@ version: '3'
 services:
  # ... define other services using the `data` volume here
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
      AWS_ENDPOINT: minio.example.com
-      AWS_BUCKET_NAME: backup-bucket
+      AWS_S3_BUCKET_NAME: backup-bucket
      AWS_ACCESS_KEY_ID: MINIOACCESSKEY
      AWS_SECRET_ACCESS_KEY: MINIOSECRETKEY
    volumes:
@@ -749,6 +955,38 @@ volumes:
  data:
 ```

+
+### Backing up to MinIO (using Docker secrets)
+
+```yml
+version: '3'
+
+services:
+  # ... define other services using the `data` volume here
+  backup:
+    image: offen/docker-volume-backup:v2
+    environment:
+      AWS_ENDPOINT: minio.example.com
+      AWS_S3_BUCKET_NAME: backup-bucket
+      AWS_ACCESS_KEY_ID_FILE: /run/secrets/minio_access_key
+      AWS_SECRET_ACCESS_KEY_FILE: /run/secrets/minio_secret_key
+    volumes:
+      - data:/backup/my-app-backup:ro
+      - /var/run/docker.sock:/var/run/docker.sock:ro
+    secrets:
+      - minio_access_key
+      - minio_secret_key
+
+volumes:
+  data:
+
+secrets:
+  minio_access_key:
+    # ... define how secret is accessed
+  minio_secret_key:
+    # ... define how secret is accessed
+```
+
 ### Backing up to WebDAV

 ```yml
@@ -757,7 +995,7 @@ version: '3'
 services:
  # ... define other services using the `data` volume here
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
      WEBDAV_URL: https://webdav.mydomain.me
      WEBDAV_PATH: /my/directory/
@@ -771,6 +1009,29 @@ volumes:
  data:
 ```

+### Backing up to SSH
+
+```yml
+version: '3'
+
+services:
+  # ... define other services using the `data` volume here
+  backup:
+    image: offen/docker-volume-backup:v2
+    environment:
+      SSH_HOST_NAME: server.local
+      SSH_PORT: 2222
+      SSH_USER: user
+      SSH_REMOTE_PATH: /data
+    volumes:
+      - data:/backup/my-app-backup:ro
+      - /var/run/docker.sock:/var/run/docker.sock:ro
+      - /path/to/private_key:/root/.ssh/id_rsa
+
+volumes:
+  data:
+```
+
 ### Backing up locally

 ```yml
@@ -779,7 +1040,7 @@ version: '3'
 services:
  # ... define other services using the `data` volume here
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
      BACKUP_FILENAME: backup-%Y-%m-%dT%H-%M-%S.tar.gz
      BACKUP_LATEST_SYMLINK: backup-latest.tar.gz
@@ -800,9 +1061,9 @@ version: '3'
 services:
  # ... define other services using the `data` volume here
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
-      AWS_BUCKET_NAME: backup-bucket
+      AWS_S3_BUCKET_NAME: backup-bucket
      AWS_ACCESS_KEY_ID: AKIAIOSFODNN7EXAMPLE
      AWS_SECRET_ACCESS_KEY: wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
    volumes:
@@ -822,11 +1083,11 @@ version: '3'
 services:
  # ... define other services using the `data` volume here
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
      # take a backup on every hour
      BACKUP_CRON_EXPRESSION: "0 * * * *"
-      AWS_BUCKET_NAME: backup-bucket
+      AWS_S3_BUCKET_NAME: backup-bucket
      AWS_ACCESS_KEY_ID: AKIAIOSFODNN7EXAMPLE
      AWS_SECRET_ACCESS_KEY: wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
    volumes:
@@ -845,9 +1106,9 @@ version: '3'
 services:
  # ... define other services using the `data` volume here
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
-      AWS_BUCKET_NAME: backup-bucket
+      AWS_S3_BUCKET_NAME: backup-bucket
      AWS_ACCESS_KEY_ID: AKIAIOSFODNN7EXAMPLE
      AWS_SECRET_ACCESS_KEY: wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
      BACKUP_FILENAME: backup-%Y-%m-%dT%H-%M-%S.tar.gz
@@ -869,9 +1130,9 @@ version: '3'
 services:
  # ... define other services using the `data` volume here
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
-      AWS_BUCKET_NAME: backup-bucket
+      AWS_S3_BUCKET_NAME: backup-bucket
      AWS_ACCESS_KEY_ID: AKIAIOSFODNN7EXAMPLE
      AWS_SECRET_ACCESS_KEY: wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
      GPG_PASSPHRASE: somesecretstring
@@ -892,11 +1153,11 @@ services:
  database:
    image: mariadb:latest
    labels:
-      - docker-volume-backup.exec-pre=/bin/sh -c 'mysqldump -psecret --all-databases > /tmp/dumps/dump.sql'
+      - docker-volume-backup.archive-pre=/bin/sh -c 'mysqldump -psecret --all-databases > /tmp/dumps/dump.sql'
    volumes:
-      - app_data:/tmp/dumps
+      - data:/tmp/dumps
  backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment:
      BACKUP_FILENAME: db.tar.gz
      BACKUP_CRON_EXPRESSION: "0 2 * * *"
@@ -917,10 +1178,10 @@ version: '3'
 services:
  # ... define other services using the `data_1` and `data_2` volumes here
  backup_1: &backup_service
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
    environment: &backup_environment
      BACKUP_CRON_EXPRESSION: "0 2 * * *"
-      AWS_BUCKET_NAME: backup-bucket
+      AWS_S3_BUCKET_NAME: backup-bucket
      AWS_ACCESS_KEY_ID: AKIAIOSFODNN7EXAMPLE
      AWS_SECRET_ACCESS_KEY: wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
      # Label the container using the `data_1` volume as `docker-volume-backup.stop-during-backup=service1`
--- a/cmd/backup/archive.go
+++ b/cmd/backup/archive.go
@@ -11,14 +11,13 @@ import (
 	"compress/gzip"
 	"fmt"
 	"io"
-	"io/fs"
 	"os"
 	"path"
 	"path/filepath"
 	"strings"
 )

-func createArchive(inputFilePath, outputFilePath string) error {
+func createArchive(files []string, inputFilePath, outputFilePath string) error {
 	inputFilePath = stripTrailingSlashes(inputFilePath)
 	inputFilePath, outputFilePath, err := makeAbsolute(inputFilePath, outputFilePath)
 	if err != nil {
@@ -28,7 +27,7 @@ func createArchive(inputFilePath, outputFilePath string) error {
 		return fmt.Errorf("createArchive: error creating output file path: %w", err)
 	}

-	if err := compress(inputFilePath, outputFilePath, filepath.Dir(inputFilePath)); err != nil {
+	if err := compress(files, outputFilePath, filepath.Dir(inputFilePath)); err != nil {
 		return fmt.Errorf("createArchive: error creating archive: %w", err)
 	}

@@ -52,7 +51,7 @@ func makeAbsolute(inputFilePath, outputFilePath string) (string, string, error)
 	return inputFilePath, outputFilePath, err
 }

-func compress(inPath, outFilePath, subPath string) error {
+func compress(paths []string, outFilePath, subPath string) error {
 	file, err := os.Create(outFilePath)
 	if err != nil {
 		return fmt.Errorf("compress: error creating out file: %w", err)
@@ -62,17 +61,9 @@ func compress(inPath, outFilePath, subPath string) error {
 	gzipWriter := gzip.NewWriter(file)
 	tarWriter := tar.NewWriter(gzipWriter)

-	var paths []string
-	if err := filepath.WalkDir(inPath, func(path string, di fs.DirEntry, err error) error {
-		paths = append(paths, path)
-		return err
-	}); err != nil {
-		return fmt.Errorf("compress: error walking filesystem tree: %w", err)
-	}
-
 	for _, p := range paths {
 		if err := writeTarGz(p, tarWriter, prefix); err != nil {
-			return fmt.Errorf("compress error writing %s to archive: %w", p, err)
+			return fmt.Errorf("compress: error writing %s to archive: %w", p, err)
 		}
 	}

--- a/cmd/backup/config.go
+++ b/cmd/backup/config.go
@@ -3,11 +3,27 @@

 package main

-import "time"
+import (
+	"os"
+	"fmt"
+	"regexp"
+	"time"
+)

 // Config holds all configuration values that are expected to be set
 // by users.
 type Config struct {
+	AwsS3BucketName            string        `split_words:"true"`
+	AwsS3Path                  string        `split_words:"true"`
+	AwsEndpoint                string        `split_words:"true" default:"s3.amazonaws.com"`
+	AwsEndpointProto           string        `split_words:"true" default:"https"`
+	AwsEndpointInsecure        bool          `split_words:"true"`
+	AwsStorageClass            string        `split_words:"true"`
+	AwsAccessKeyID             string        `envconfig:"AWS_ACCESS_KEY_ID"`
+	AwsAccessKeyIDFile         string        `envconfig:"AWS_ACCESS_KEY_ID_FILE"`
+	AwsSecretAccessKey         string        `split_words:"true"`
+	AwsSecretAccessKeyFile     string        `split_words:"true"`
+	AwsIamRoleEndpoint         string        `split_words:"true"`
 	BackupSources              string        `split_words:"true" default:"/backup"`
 	BackupFilename             string        `split_words:"true" default:"backup-%Y-%m-%dT%H-%M-%S.tar.gz"`
 	BackupFilenameExpand       bool          `split_words:"true"`
@@ -18,14 +34,7 @@ type Config struct {
 	BackupPruningPrefix        string        `split_words:"true"`
 	BackupStopContainerLabel   string        `split_words:"true" default:"true"`
 	BackupFromSnapshot         bool          `split_words:"true"`
-	AwsS3BucketName            string        `split_words:"true"`
-	AwsS3Path                  string        `split_words:"true"`
-	AwsEndpoint                string        `split_words:"true" default:"s3.amazonaws.com"`
-	AwsEndpointProto           string        `split_words:"true" default:"https"`
-	AwsEndpointInsecure        bool          `split_words:"true"`
-	AwsAccessKeyID             string        `envconfig:"AWS_ACCESS_KEY_ID"`
-	AwsSecretAccessKey         string        `split_words:"true"`
-	AwsIamRoleEndpoint         string        `split_words:"true"`
+	BackupExcludeRegexp        RegexpDecoder `split_words:"true"`
 	GpgPassphrase              string        `split_words:"true"`
 	NotificationURLs           []string      `envconfig:"NOTIFICATION_URLS"`
 	NotificationLevel          string        `split_words:"true" default:"error"`
@@ -36,9 +45,45 @@ type Config struct {
 	EmailSMTPUsername          string        `envconfig:"EMAIL_SMTP_USERNAME"`
 	EmailSMTPPassword          string        `envconfig:"EMAIL_SMTP_PASSWORD"`
 	WebdavUrl                  string        `split_words:"true"`
+	WebdavUrlInsecure          bool          `split_words:"true"`
 	WebdavPath                 string        `split_words:"true" default:"/"`
 	WebdavUsername             string        `split_words:"true"`
 	WebdavPassword             string        `split_words:"true"`
+	SSHHostName                string        `split_words:"true"`
+	SSHPort                    string        `split_words:"true" default:"22"`
+	SSHUser                    string        `split_words:"true"`
+	SSHPassword                string        `split_words:"true"`
+	SSHIdentityFile            string        `split_words:"true" default:"/root/.ssh/id_rsa"`
+	SSHIdentityPassphrase      string        `split_words:"true"`
+	SSHRemotePath              string        `split_words:"true"`
 	ExecLabel                  string        `split_words:"true"`
 	ExecForwardOutput          bool          `split_words:"true"`
+	LockTimeout                time.Duration `split_words:"true" default:"60m"`
+}
+
+func (c *Config) resolveSecret(envVar string, secretPath string) (string, error) {
+	if secretPath != "" {
+		data, err := os.ReadFile(secretPath)
+		if err != nil {
+			return "", fmt.Errorf("resolveSecret: error reading secret path: %w", err)
+		}
+		return string(data), nil
+	}
+	return envVar, nil
+}
+
+type RegexpDecoder struct {
+	Re *regexp.Regexp
+}
+
+func (r *RegexpDecoder) Decode(v string) error {
+	if v == "" {
+		return nil
+	}
+	re, err := regexp.Compile(v)
+	if err != nil {
+		return fmt.Errorf("config: error compiling given regexp `%s`: %w", v, err)
+	}
+	*r = RegexpDecoder{Re: re}
+	return nil
 }
--- a/cmd/backup/exec.go
+++ b/cmd/backup/exec.go
@@ -1,6 +1,9 @@
 // Copyright 2022 - Offen Authors <hioffen@posteo.de>
 // SPDX-License-Identifier: MPL-2.0

+// Portions of this file are taken and adapted from `moby`, Copyright 2012-2017 Docker, Inc.
+// Licensed under the Apache 2.0 License: https://github.com/moby/moby/blob/8e610b2b55bfd1bfa9436ab110d311f5e8a74dcb/LICENSE
+
 package main

 import (
@@ -10,12 +13,12 @@ import (
 	"io/ioutil"
 	"os"
 	"strings"
-	"sync"

 	"github.com/cosiner/argv"
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/filters"
 	"github.com/docker/docker/pkg/stdcopy"
+	"golang.org/x/sync/errgroup"
 )

 func (s *script) exec(containerRef string, command string) ([]byte, []byte, error) {
@@ -90,33 +93,107 @@ func (s *script) runLabeledCommands(label string) error {
 		return fmt.Errorf("runLabeledCommands: error querying for containers: %w", err)
 	}

+	var hasDeprecatedContainers bool
+	if label == "docker-volume-backup.archive-pre" {
+		f[0] = filters.KeyValuePair{
+			Key:   "label",
+			Value: "docker-volume-backup.exec-pre",
+		}
+		deprecatedContainers, err := s.cli.ContainerList(context.Background(), types.ContainerListOptions{
+			Quiet:   true,
+			Filters: filters.NewArgs(f...),
+		})
+		if err != nil {
+			return fmt.Errorf("runLabeledCommands: error querying for containers: %w", err)
+		}
+		if len(deprecatedContainers) != 0 {
+			hasDeprecatedContainers = true
+			containersWithCommand = append(containersWithCommand, deprecatedContainers...)
+		}
+	}
+
+	if label == "docker-volume-backup.archive-post" {
+		f[0] = filters.KeyValuePair{
+			Key:   "label",
+			Value: "docker-volume-backup.exec-post",
+		}
+		deprecatedContainers, err := s.cli.ContainerList(context.Background(), types.ContainerListOptions{
+			Quiet:   true,
+			Filters: filters.NewArgs(f...),
+		})
+		if err != nil {
+			return fmt.Errorf("runLabeledCommands: error querying for containers: %w", err)
+		}
+		if len(deprecatedContainers) != 0 {
+			hasDeprecatedContainers = true
+			containersWithCommand = append(containersWithCommand, deprecatedContainers...)
+		}
+	}
+
 	if len(containersWithCommand) == 0 {
 		return nil
 	}

-	wg := sync.WaitGroup{}
-	wg.Add(len(containersWithCommand))
+	if hasDeprecatedContainers {
+		s.logger.Warn(
+			"Using `docker-volume-backup.exec-pre` and `docker-volume-backup.exec-post` labels has been deprecated and will be removed in the next major version.",
+		)
+		s.logger.Warn(
+			"Please use other `-pre` and `-post` labels instead. Refer to the README for an upgrade guide.",
+		)
+	}
+
+	g := new(errgroup.Group)

-	var cmdErrors []error
 	for _, container := range containersWithCommand {
-		go func(c types.Container) {
-			cmd, _ := c.Labels[label]
+		c := container
+		g.Go(func() error {
+			cmd, ok := c.Labels[label]
+			if !ok && label == "docker-volume-backup.archive-pre" {
+				cmd, _ = c.Labels["docker-volume-backup.exec-pre"]
+			} else if !ok && label == "docker-volume-backup.archive-post" {
+				cmd, _ = c.Labels["docker-volume-backup.exec-post"]
+			}
+
 			s.logger.Infof("Running %s command %s for container %s", label, cmd, strings.TrimPrefix(c.Names[0], "/"))
 			stdout, stderr, err := s.exec(c.ID, cmd)
-			if err != nil {
-				cmdErrors = append(cmdErrors, err)
-			}
 			if s.c.ExecForwardOutput {
 				os.Stderr.Write(stderr)
 				os.Stdout.Write(stdout)
 			}
-			wg.Done()
-		}(container)
+			if err != nil {
+				return fmt.Errorf("runLabeledCommands: error executing command: %w", err)
+			}
+			return nil
+		})
 	}

-	wg.Wait()
-	if len(cmdErrors) != 0 {
-		return join(cmdErrors...)
+	if err := g.Wait(); err != nil {
+		return fmt.Errorf("runLabeledCommands: error from errgroup: %w", err)
 	}
 	return nil
 }
+
+type lifecyclePhase string
+
+const (
+	lifecyclePhaseArchive lifecyclePhase = "archive"
+	lifecyclePhaseProcess lifecyclePhase = "process"
+	lifecyclePhaseCopy    lifecyclePhase = "copy"
+	lifecyclePhasePrune   lifecyclePhase = "prune"
+)
+
+func (s *script) withLabeledCommands(step lifecyclePhase, cb func() error) func() error {
+	if s.cli == nil {
+		return cb
+	}
+	return func() error {
+		if err := s.runLabeledCommands(fmt.Sprintf("docker-volume-backup.%s-pre", step)); err != nil {
+			return fmt.Errorf("withLabeledCommands: %s: error running pre commands: %w", step, err)
+		}
+		defer func() {
+			s.must(s.runLabeledCommands(fmt.Sprintf("docker-volume-backup.%s-post", step)))
+		}()
+		return cb()
+	}
+}
--- a/cmd/backup/hooks.go
+++ b/cmd/backup/hooks.go
@@ -6,6 +6,8 @@ package main
 import (
 	"fmt"
 	"sort"
+
+	"github.com/offen/docker-volume-backup/internal/utilities"
 )

 // hook contains a queued action that can be trigger them when the script
@@ -50,7 +52,7 @@ func (s *script) runHooks(err error) error {
 		}
 	}
 	if len(actionErrors) != 0 {
-		return join(actionErrors...)
+		return utilities.Join(actionErrors...)
 	}
 	return nil
 }
--- a/cmd/backup/lock.go
+++ b/cmd/backup/lock.go
@@ -0,0 +1,58 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
+package main
+
+import (
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/gofrs/flock"
+)
+
+// lock opens a lockfile at the given location, keeping it locked until the
+// caller invokes the returned release func. In case the lock is currently blocked
+// by another execution, it will repeatedly retry until the lock is available
+// or the given timeout is exceeded.
+func (s *script) lock(lockfile string) (func() error, error) {
+	start := time.Now()
+	defer func() {
+		s.stats.LockedTime = time.Now().Sub(start)
+	}()
+
+	retry := time.NewTicker(5 * time.Second)
+	defer retry.Stop()
+	deadline := time.NewTimer(s.c.LockTimeout)
+	defer deadline.Stop()
+
+	fileLock := flock.New(lockfile)
+
+	for {
+		acquired, err := fileLock.TryLock()
+		if err != nil {
+			return noop, fmt.Errorf("lock: error trying to lock: %w", err)
+		}
+		if acquired {
+			if s.encounteredLock {
+				s.logger.Info("Acquired exclusive lock on subsequent attempt, ready to continue.")
+			}
+			return fileLock.Unlock, nil
+		}
+
+		if !s.encounteredLock {
+			s.logger.Infof(
+				"Exclusive lock was not available on first attempt. Will retry until it becomes available or the timeout of %s is exceeded.",
+				s.c.LockTimeout,
+			)
+			s.encounteredLock = true
+		}
+
+		select {
+		case <-retry.C:
+			continue
+		case <-deadline.C:
+			return noop, errors.New("lock: timed out waiting for lockfile to become available")
+		}
+	}
+}
--- a/cmd/backup/main.go
+++ b/cmd/backup/main.go
@@ -8,14 +8,15 @@ import (
 )

 func main() {
-	unlock := lock("/var/lock/dockervolumebackup.lock")
-	defer unlock()
-
 	s, err := newScript()
 	if err != nil {
 		panic(err)
 	}

+	unlock, err := s.lock("/var/lock/dockervolumebackup.lock")
+	defer unlock()
+	s.must(err)
+
 	defer func() {
 		if pArg := recover(); pArg != nil {
 			if err, ok := pArg.(error); ok {
@@ -37,14 +38,7 @@ func main() {
 		s.logger.Info("Finished running backup tasks.")
 	}()

-	s.must(func() error {
-		runPostCommands, err := s.runCommands()
-		defer func() {
-			s.must(runPostCommands())
-		}()
-		if err != nil {
-			return err
-		}
+	s.must(s.withLabeledCommands(lifecyclePhaseArchive, func() error {
 		restartContainers, err := s.stopContainers()
 		// The mechanism for restarting containers is not using hooks as it
 		// should happen as soon as possible (i.e. before uploading backups or
@@ -55,10 +49,10 @@ func main() {
 		if err != nil {
 			return err
 		}
-		return s.takeBackup()
-	}())
+		return s.createArchive()
+	})())

-	s.must(s.encryptBackup())
-	s.must(s.copyBackup())
-	s.must(s.pruneBackups())
+	s.must(s.withLabeledCommands(lifecyclePhaseProcess, s.encryptArchive)())
+	s.must(s.withLabeledCommands(lifecyclePhaseCopy, s.copyArchive)())
+	s.must(s.withLabeledCommands(lifecyclePhasePrune, s.pruneBackups)())
 }
--- a/cmd/backup/notifications.go
+++ b/cmd/backup/notifications.go
@@ -7,10 +7,12 @@ import (
 	"bytes"
 	_ "embed"
 	"fmt"
+	"os"
 	"text/template"
 	"time"

 	sTypes "github.com/containrrr/shoutrrr/pkg/types"
+	"github.com/offen/docker-volume-backup/internal/utilities"
 )

 //go:embed notifications.tmpl
@@ -34,16 +36,16 @@ func (s *script) notify(titleTemplate string, bodyTemplate string, err error) er

 	titleBuf := &bytes.Buffer{}
 	if err := s.template.ExecuteTemplate(titleBuf, titleTemplate, params); err != nil {
-		return fmt.Errorf("notifyFailure: error executing %s template: %w", titleTemplate, err)
+		return fmt.Errorf("notify: error executing %s template: %w", titleTemplate, err)
 	}

 	bodyBuf := &bytes.Buffer{}
 	if err := s.template.ExecuteTemplate(bodyBuf, bodyTemplate, params); err != nil {
-		return fmt.Errorf("notifyFailure: error executing %s template: %w", bodyTemplate, err)
+		return fmt.Errorf("notify: error executing %s template: %w", bodyTemplate, err)
 	}

 	if err := s.sendNotification(titleBuf.String(), bodyBuf.String()); err != nil {
-		return fmt.Errorf("notifyFailure: error notifying: %w", err)
+		return fmt.Errorf("notify: error notifying: %w", err)
 	}
 	return nil
 }
@@ -67,7 +69,7 @@ func (s *script) sendNotification(title, body string) error {
 		}
 	}
 	if len(errs) != 0 {
-		return fmt.Errorf("sendNotification: error sending message: %w", join(errs...))
+		return fmt.Errorf("sendNotification: error sending message: %w", utilities.Join(errs...))
 	}
 	return nil
 }
@@ -82,6 +84,7 @@ var templateHelpers = template.FuncMap{
 	"formatBytesBin": func(bytes uint64) string {
 		return formatBytes(bytes, false)
 	},
+	"env": os.Getenv,
 }

 // formatBytes converts an amount of bytes in a human-readable representation
--- a/cmd/backup/script.go
+++ b/cmd/backup/script.go
@@ -5,7 +5,6 @@ package main

 import (
 	"context"
-	"errors"
 	"fmt"
 	"io"
 	"io/fs"
@@ -15,6 +14,13 @@ import (
 	"text/template"
 	"time"

+	"github.com/offen/docker-volume-backup/internal/storage"
+	"github.com/offen/docker-volume-backup/internal/storage/local"
+	"github.com/offen/docker-volume-backup/internal/storage/s3"
+	"github.com/offen/docker-volume-backup/internal/storage/ssh"
+	"github.com/offen/docker-volume-backup/internal/storage/webdav"
+	"github.com/offen/docker-volume-backup/internal/utilities"
+
 	"github.com/containrrr/shoutrrr"
 	"github.com/containrrr/shoutrrr/pkg/router"
 	"github.com/docker/docker/api/types"
@@ -23,20 +29,17 @@ import (
 	"github.com/docker/docker/client"
 	"github.com/kelseyhightower/envconfig"
 	"github.com/leekchan/timeutil"
-	"github.com/minio/minio-go/v7"
-	"github.com/minio/minio-go/v7/pkg/credentials"
 	"github.com/otiai10/copy"
 	"github.com/sirupsen/logrus"
-	"github.com/studio-b12/gowebdav"
 	"golang.org/x/crypto/openpgp"
+	"golang.org/x/sync/errgroup"
 )

 // script holds all the stateful information required to orchestrate a
 // single backup run.
 type script struct {
 	cli       *client.Client
-	minioClient  *minio.Client
-	webdavClient *gowebdav.Client
+	storages  []storage.Backend
 	logger    *logrus.Logger
 	sender    *router.ServiceRouter
 	template  *template.Template
@@ -46,6 +49,8 @@ type script struct {
 	file  string
 	stats *Stats

+	encounteredLock bool
+
 	c *Config
 }

@@ -66,7 +71,12 @@ func newScript() (*script, error) {
 		stats: &Stats{
 			StartTime: time.Now(),
 			LogOutput: logBuffer,
-			Storages:  StoragesStats{},
+			Storages: map[string]StorageStats{
+				"S3":     {},
+				"WebDAV": {},
+				"SSH":    {},
+				"Local":  {},
+			},
 		},
 	}

@@ -98,52 +108,84 @@ func newScript() (*script, error) {
 		s.cli = cli
 	}

+	logFunc := func(logType storage.LogLevel, context string, msg string, params ...interface{}) {
+		switch logType {
+		case storage.LogLevelWarning:
+			s.logger.Warnf("["+context+"] "+msg, params...)
+		case storage.LogLevelError:
+			s.logger.Errorf("["+context+"] "+msg, params...)
+		case storage.LogLevelInfo:
+		default:
+			s.logger.Infof("["+context+"] "+msg, params...)
+		}
+	}
+
 	if s.c.AwsS3BucketName != "" {
-		var creds *credentials.Credentials
-		if s.c.AwsAccessKeyID != "" && s.c.AwsSecretAccessKey != "" {
-			creds = credentials.NewStaticV4(
-				s.c.AwsAccessKeyID,
-				s.c.AwsSecretAccessKey,
-				"",
-			)
-		} else if s.c.AwsIamRoleEndpoint != "" {
-			creds = credentials.NewIAM(s.c.AwsIamRoleEndpoint)
+		accessKeyID, err := s.c.resolveSecret(s.c.AwsAccessKeyID, s.c.AwsAccessKeyIDFile)
+		if err != nil {
+			return nil, fmt.Errorf("newScript: error resolving AwsAccessKeyID: %w", err)
+		}
+		secretAccessKey, err := s.c.resolveSecret(s.c.AwsSecretAccessKey, s.c.AwsSecretAccessKeyFile)
+		if err != nil {
+			return nil, fmt.Errorf("newScript: error resolving AwsSecretAccessKey: %w", err)
+		}
+		s3Config := s3.Config{
+			Endpoint:         s.c.AwsEndpoint,
+			AccessKeyID:      accessKeyID,
+			SecretAccessKey:  secretAccessKey,
+			IamRoleEndpoint:  s.c.AwsIamRoleEndpoint,
+			EndpointProto:    s.c.AwsEndpointProto,
+			EndpointInsecure: s.c.AwsEndpointInsecure,
+			RemotePath:       s.c.AwsS3Path,
+			BucketName:       s.c.AwsS3BucketName,
+			StorageClass:     s.c.AwsStorageClass,
+		}
+		if s3Backend, err := s3.NewStorageBackend(s3Config, logFunc); err != nil {
+			return nil, err
 		} else {
-			return nil, errors.New("newScript: AWS_S3_BUCKET_NAME is defined, but no credentials were provided")
+			s.storages = append(s.storages, s3Backend)
 		}
-
-		options := minio.Options{
-			Creds:  creds,
-			Secure: s.c.AwsEndpointProto == "https",
-		}
-
-		if s.c.AwsEndpointInsecure {
-			if !options.Secure {
-				return nil, errors.New("newScript: AWS_ENDPOINT_INSECURE = true is only meaningful for https")
-			}
-
-			transport, err := minio.DefaultTransport(true)
-			if err != nil {
-				return nil, fmt.Errorf("newScript: failed to create default minio transport")
-			}
-			transport.TLSClientConfig.InsecureSkipVerify = true
-			options.Transport = transport
-		}
-
-		mc, err := minio.New(s.c.AwsEndpoint, &options)
-		if err != nil {
-			return nil, fmt.Errorf("newScript: error setting up minio client: %w", err)
-		}
-		s.minioClient = mc
 	}

 	if s.c.WebdavUrl != "" {
-		if s.c.WebdavUsername == "" || s.c.WebdavPassword == "" {
-			return nil, errors.New("newScript: WEBDAV_URL is defined, but no credentials were provided")
-		} else {
-			webdavClient := gowebdav.NewClient(s.c.WebdavUrl, s.c.WebdavUsername, s.c.WebdavPassword)
-			s.webdavClient = webdavClient
+		webDavConfig := webdav.Config{
+			URL:         s.c.WebdavUrl,
+			URLInsecure: s.c.WebdavUrlInsecure,
+			Username:    s.c.WebdavUsername,
+			Password:    s.c.WebdavPassword,
+			RemotePath:  s.c.WebdavPath,
 		}
+		if webdavBackend, err := webdav.NewStorageBackend(webDavConfig, logFunc); err != nil {
+			return nil, err
+		} else {
+			s.storages = append(s.storages, webdavBackend)
+		}
+	}
+
+	if s.c.SSHHostName != "" {
+		sshConfig := ssh.Config{
+			HostName:           s.c.SSHHostName,
+			Port:               s.c.SSHPort,
+			User:               s.c.SSHUser,
+			Password:           s.c.SSHPassword,
+			IdentityFile:       s.c.SSHIdentityFile,
+			IdentityPassphrase: s.c.SSHIdentityPassphrase,
+			RemotePath:         s.c.SSHRemotePath,
+		}
+		if sshBackend, err := ssh.NewStorageBackend(sshConfig, logFunc); err != nil {
+			return nil, err
+		} else {
+			s.storages = append(s.storages, sshBackend)
+		}
+	}
+
+	if _, err := os.Stat(s.c.BackupArchive); !os.IsNotExist(err) {
+		localConfig := local.Config{
+			ArchivePath:   s.c.BackupArchive,
+			LatestSymlink: s.c.BackupLatestSymlink,
+		}
+		localBackend := local.NewStorageBackend(localConfig, logFunc)
+		s.storages = append(s.storages, localBackend)
 	}

 	if s.c.EmailNotificationRecipient != "" {
@@ -212,22 +254,6 @@ func newScript() (*script, error) {
 	return s, nil
 }

-func (s *script) runCommands() (func() error, error) {
-	if s.cli == nil {
-		return noop, nil
-	}
-
-	if err := s.runLabeledCommands("docker-volume-backup.exec-pre"); err != nil {
-		return noop, fmt.Errorf("runCommands: error running pre commands: %w", err)
-	}
-	return func() error {
-		if err := s.runLabeledCommands("docker-volume-backup.exec-post"); err != nil {
-			return fmt.Errorf("runCommands: error running post commands: %w", err)
-		}
-		return nil
-	}, nil
-}
-
 // stopContainers stops all Docker containers that are marked as to being
 // stopped during the backup and returns a function that can be called to
 // restart everything that has been stopped.
@@ -240,7 +266,7 @@ func (s *script) stopContainers() (func() error, error) {
 		Quiet: true,
 	})
 	if err != nil {
-		return noop, fmt.Errorf("stopContainersAndRun: error querying for containers: %w", err)
+		return noop, fmt.Errorf("stopContainers: error querying for containers: %w", err)
 	}

 	containerLabel := fmt.Sprintf(
@@ -256,7 +282,7 @@ func (s *script) stopContainers() (func() error, error) {
 	})

 	if err != nil {
-		return noop, fmt.Errorf("stopContainersAndRun: error querying for containers to stop: %w", err)
+		return noop, fmt.Errorf("stopContainers: error querying for containers to stop: %w", err)
 	}

 	if len(containersToStop) == 0 {
@@ -283,9 +309,9 @@ func (s *script) stopContainers() (func() error, error) {
 	var stopError error
 	if len(stopErrors) != 0 {
 		stopError = fmt.Errorf(
-			"stopContainersAndRun: %d error(s) stopping containers: %w",
+			"stopContainers: %d error(s) stopping containers: %w",
 			len(stopErrors),
-			join(stopErrors...),
+			utilities.Join(stopErrors...),
 		)
 	}

@@ -320,7 +346,7 @@ func (s *script) stopContainers() (func() error, error) {
 					}
 				}
 				if serviceMatch.ID == "" {
-					return fmt.Errorf("stopContainersAndRun: couldn't find service with name %s", serviceName)
+					return fmt.Errorf("stopContainers: couldn't find service with name %s", serviceName)
 				}
 				serviceMatch.Spec.TaskTemplate.ForceUpdate = 1
 				if _, err := s.cli.ServiceUpdate(
@@ -334,9 +360,9 @@ func (s *script) stopContainers() (func() error, error) {

 		if len(restartErrors) != 0 {
 			return fmt.Errorf(
-				"stopContainersAndRun: %d error(s) restarting containers and services: %w",
+				"stopContainers: %d error(s) restarting containers and services: %w",
 				len(restartErrors),
-				join(restartErrors...),
+				utilities.Join(restartErrors...),
 			)
 		}
 		s.logger.Infof(
@@ -347,17 +373,23 @@ func (s *script) stopContainers() (func() error, error) {
 	}, stopError
 }

-// takeBackup creates a tar archive of the configured backup location and
+// createArchive creates a tar archive of the configured backup location and
 // saves it to disk.
-func (s *script) takeBackup() error {
+func (s *script) createArchive() error {
 	backupSources := s.c.BackupSources

 	if s.c.BackupFromSnapshot {
+		s.logger.Warn(
+			"Using BACKUP_FROM_SNAPSHOT has been deprecated and will be removed in the next major version.",
+		)
+		s.logger.Warn(
+			"Please use `archive-pre` and `archive-post` commands to prepare your backup sources. Refer to the README for an upgrade guide.",
+		)
 		backupSources = filepath.Join("/tmp", s.c.BackupSources)
 		// copy before compressing guard against a situation where backup folder's content are still growing.
 		s.registerHook(hookLevelPlumbing, func(error) error {
 			if err := remove(backupSources); err != nil {
-				return fmt.Errorf("takeBackup: error removing snapshot: %w", err)
+				return fmt.Errorf("createArchive: error removing snapshot: %w", err)
 			}
 			s.logger.Infof("Removed snapshot `%s`.", backupSources)
 			return nil
@@ -366,7 +398,7 @@ func (s *script) takeBackup() error {
 			PreserveTimes: true,
 			PreserveOwner: true,
 		}); err != nil {
-			return fmt.Errorf("takeBackup: error creating snapshot: %w", err)
+			return fmt.Errorf("createArchive: error creating snapshot: %w", err)
 		}
 		s.logger.Infof("Created snapshot of `%s` at `%s`.", s.c.BackupSources, backupSources)
 	}
@@ -374,23 +406,44 @@ func (s *script) takeBackup() error {
 	tarFile := s.file
 	s.registerHook(hookLevelPlumbing, func(error) error {
 		if err := remove(tarFile); err != nil {
-			return fmt.Errorf("takeBackup: error removing tar file: %w", err)
+			return fmt.Errorf("createArchive: error removing tar file: %w", err)
 		}
 		s.logger.Infof("Removed tar file `%s`.", tarFile)
 		return nil
 	})
-	if err := createArchive(backupSources, tarFile); err != nil {
-		return fmt.Errorf("takeBackup: error compressing backup folder: %w", err)
+
+	backupPath, err := filepath.Abs(stripTrailingSlashes(backupSources))
+	if err != nil {
+		return fmt.Errorf("createArchive: error getting absolute path: %w", err)
+	}
+
+	var filesEligibleForBackup []string
+	if err := filepath.WalkDir(backupPath, func(path string, di fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+
+		if s.c.BackupExcludeRegexp.Re != nil && s.c.BackupExcludeRegexp.Re.MatchString(path) {
+			return nil
+		}
+		filesEligibleForBackup = append(filesEligibleForBackup, path)
+		return nil
+	}); err != nil {
+		return fmt.Errorf("createArchive: error walking filesystem tree: %w", err)
+	}
+
+	if err := createArchive(filesEligibleForBackup, backupSources, tarFile); err != nil {
+		return fmt.Errorf("createArchive: error compressing backup folder: %w", err)
 	}

 	s.logger.Infof("Created backup of `%s` at `%s`.", backupSources, tarFile)
 	return nil
 }

-// encryptBackup encrypts the backup file using PGP and the configured passphrase.
+// encryptArchive encrypts the backup file using PGP and the configured passphrase.
 // In case no passphrase is given it returns early, leaving the backup file
 // untouched.
-func (s *script) encryptBackup() error {
+func (s *script) encryptArchive() error {
 	if s.c.GpgPassphrase == "" {
 		return nil
 	}
@@ -398,35 +451,35 @@ func (s *script) encryptBackup() error {
 	gpgFile := fmt.Sprintf("%s.gpg", s.file)
 	s.registerHook(hookLevelPlumbing, func(error) error {
 		if err := remove(gpgFile); err != nil {
-			return fmt.Errorf("encryptBackup: error removing gpg file: %w", err)
+			return fmt.Errorf("encryptArchive: error removing gpg file: %w", err)
 		}
 		s.logger.Infof("Removed GPG file `%s`.", gpgFile)
 		return nil
 	})

 	outFile, err := os.Create(gpgFile)
-	defer outFile.Close()
 	if err != nil {
-		return fmt.Errorf("encryptBackup: error opening out file: %w", err)
+		return fmt.Errorf("encryptArchive: error opening out file: %w", err)
 	}
+	defer outFile.Close()

 	_, name := path.Split(s.file)
 	dst, err := openpgp.SymmetricallyEncrypt(outFile, []byte(s.c.GpgPassphrase), &openpgp.FileHints{
 		IsBinary: true,
 		FileName: name,
 	}, nil)
-	defer dst.Close()
 	if err != nil {
-		return fmt.Errorf("encryptBackup: error encrypting backup file: %w", err)
+		return fmt.Errorf("encryptArchive: error encrypting backup file: %w", err)
 	}
+	defer dst.Close()

 	src, err := os.Open(s.file)
 	if err != nil {
-		return fmt.Errorf("encryptBackup: error opening backup file `%s`: %w", s.file, err)
+		return fmt.Errorf("encryptArchive: error opening backup file `%s`: %w", s.file, err)
 	}

 	if _, err := io.Copy(dst, src); err != nil {
-		return fmt.Errorf("encryptBackup: error writing ciphertext to file: %w", err)
+		return fmt.Errorf("encryptArchive: error writing ciphertext to file: %w", err)
 	}

 	s.file = gpgFile
@@ -434,12 +487,12 @@ func (s *script) encryptBackup() error {
 	return nil
 }

-// copyBackup makes sure the backup file is copied to both local and remote locations
+// copyArchive makes sure the backup file is copied to both local and remote locations
 // as per the given configuration.
-func (s *script) copyBackup() error {
+func (s *script) copyArchive() error {
 	_, name := path.Split(s.file)
 	if stat, err := os.Stat(s.file); err != nil {
-		return fmt.Errorf("copyBackup: unable to stat backup file: %w", err)
+		return fmt.Errorf("copyArchive: unable to stat backup file: %w", err)
 	} else {
 		size := stat.Size()
 		s.stats.BackupFile = BackupFileStats{
@@ -449,45 +502,17 @@ func (s *script) copyBackup() error {
 		}
 	}

-	if s.minioClient != nil {
-		if _, err := s.minioClient.FPutObject(context.Background(), s.c.AwsS3BucketName, filepath.Join(s.c.AwsS3Path, name), s.file, minio.PutObjectOptions{
-			ContentType: "application/tar+gzip",
-		}); err != nil {
-			return fmt.Errorf("copyBackup: error uploading backup to remote storage: %w", err)
+	eg := errgroup.Group{}
+	for _, backend := range s.storages {
+		b := backend
+		eg.Go(func() error {
+			return b.Copy(s.file)
+		})
 	}
-		s.logger.Infof("Uploaded a copy of backup `%s` to bucket `%s`.", s.file, s.c.AwsS3BucketName)
+	if err := eg.Wait(); err != nil {
+		return fmt.Errorf("copyArchive: error copying archive: %w", err)
 	}

-	if s.webdavClient != nil {
-		bytes, err := os.ReadFile(s.file)
-		if err != nil {
-			return fmt.Errorf("copyBackup: error reading the file to be uploaded: %w", err)
-		}
-		if err := s.webdavClient.MkdirAll(s.c.WebdavPath, 0644); err != nil {
-			return fmt.Errorf("copyBackup: error creating directory '%s' on WebDAV server: %w", s.c.WebdavPath, err)
-		}
-		if err := s.webdavClient.Write(filepath.Join(s.c.WebdavPath, name), bytes, 0644); err != nil {
-			return fmt.Errorf("copyBackup: error uploading the file to WebDAV server: %w", err)
-		}
-		s.logger.Infof("Uploaded a copy of backup `%s` to WebDAV-URL '%s' at path '%s'.", s.file, s.c.WebdavUrl, s.c.WebdavPath)
-	}
-
-	if _, err := os.Stat(s.c.BackupArchive); !os.IsNotExist(err) {
-		if err := copyFile(s.file, path.Join(s.c.BackupArchive, name)); err != nil {
-			return fmt.Errorf("copyBackup: error copying file to local archive: %w", err)
-		}
-		s.logger.Infof("Stored copy of backup `%s` in local archive `%s`.", s.file, s.c.BackupArchive)
-		if s.c.BackupLatestSymlink != "" {
-			symlink := path.Join(s.c.BackupArchive, s.c.BackupLatestSymlink)
-			if _, err := os.Lstat(symlink); err == nil {
-				os.Remove(symlink)
-			}
-			if err := os.Symlink(name, symlink); err != nil {
-				return fmt.Errorf("copyBackup: error creating latest symlink: %w", err)
-			}
-			s.logger.Infof("Created/Updated symlink `%s` for latest backup.", s.c.BackupLatestSymlink)
-		}
-	}
 	return nil
 }

@@ -501,173 +526,28 @@ func (s *script) pruneBackups() error {

 	deadline := time.Now().AddDate(0, 0, -int(s.c.BackupRetentionDays)).Add(s.c.BackupPruningLeeway)

-	// doPrune holds general control flow that applies to any kind of storage.
-	// Callers can pass in a thunk that performs the actual deletion of files.
-	var doPrune = func(lenMatches, lenCandidates int, description string, doRemoveFiles func() error) error {
-		if lenMatches != 0 && lenMatches != lenCandidates {
-			if err := doRemoveFiles(); err != nil {
+	eg := errgroup.Group{}
+	for _, backend := range s.storages {
+		b := backend
+		eg.Go(func() error {
+			stats, err := b.Prune(deadline, s.c.BackupPruningPrefix)
+			if err != nil {
 				return err
 			}
-			s.logger.Infof(
-				"Pruned %d out of %d %s as their age exceeded the configured retention period of %d days.",
-				lenMatches,
-				lenCandidates,
-				description,
-				s.c.BackupRetentionDays,
-			)
-		} else if lenMatches != 0 && lenMatches == lenCandidates {
-			s.logger.Warnf("The current configuration would delete all %d existing %s.", lenMatches, description)
-			s.logger.Warn("Refusing to do so, please check your configuration.")
-		} else {
-			s.logger.Infof("None of %d existing %s were pruned.", lenCandidates, description)
-		}
-		return nil
-	}
-
-	if s.minioClient != nil {
-		candidates := s.minioClient.ListObjects(context.Background(), s.c.AwsS3BucketName, minio.ListObjectsOptions{
-			WithMetadata: true,
-			Prefix:       s.c.BackupPruningPrefix,
-		})
-
-		var matches []minio.ObjectInfo
-		var lenCandidates int
-		for candidate := range candidates {
-			lenCandidates++
-			if candidate.Err != nil {
-				return fmt.Errorf(
-					"pruneBackups: error looking up candidates from remote storage: %w",
-					candidate.Err,
-				)
-			}
-			if candidate.LastModified.Before(deadline) {
-				matches = append(matches, candidate)
-			}
-		}
-
-		s.stats.Storages.S3 = StorageStats{
-			Total:  uint(lenCandidates),
-			Pruned: uint(len(matches)),
-		}
-
-		doPrune(len(matches), lenCandidates, "remote backup(s)", func() error {
-			objectsCh := make(chan minio.ObjectInfo)
-			go func() {
-				for _, match := range matches {
-					objectsCh <- match
-				}
-				close(objectsCh)
-			}()
-			errChan := s.minioClient.RemoveObjects(context.Background(), s.c.AwsS3BucketName, objectsCh, minio.RemoveObjectsOptions{})
-			var removeErrors []error
-			for result := range errChan {
-				if result.Err != nil {
-					removeErrors = append(removeErrors, result.Err)
-				}
-			}
-			if len(removeErrors) != 0 {
-				return join(removeErrors...)
+			s.stats.Lock()
+			s.stats.Storages[b.Name()] = StorageStats{
+				Total:  stats.Total,
+				Pruned: stats.Pruned,
 			}
+			s.stats.Unlock()
 			return nil
 		})
 	}

-	if s.webdavClient != nil {
-		candidates, err := s.webdavClient.ReadDir(s.c.WebdavPath)
-		if err != nil {
-			return fmt.Errorf("pruneBackups: error looking up candidates from remote storage: %w", err)
-		}
-		var matches []fs.FileInfo
-		var lenCandidates int
-		for _, candidate := range candidates {
-			lenCandidates++
-			if candidate.ModTime().Before(deadline) {
-				matches = append(matches, candidate)
-			}
+	if err := eg.Wait(); err != nil {
+		return fmt.Errorf("pruneBackups: error pruning backups: %w", err)
 	}

-		s.stats.Storages.WebDAV = StorageStats{
-			Total:  uint(lenCandidates),
-			Pruned: uint(len(matches)),
-		}
-
-		doPrune(len(matches), lenCandidates, "WebDAV backup(s)", func() error {
-			for _, match := range matches {
-				if err := s.webdavClient.Remove(filepath.Join(s.c.WebdavPath, match.Name())); err != nil {
-					return fmt.Errorf("pruneBackups: error removing file from WebDAV storage: %w", err)
-				}
-			}
-			return nil
-		})
-	}
-
-	if _, err := os.Stat(s.c.BackupArchive); !os.IsNotExist(err) {
-		globPattern := path.Join(
-			s.c.BackupArchive,
-			fmt.Sprintf("%s*", s.c.BackupPruningPrefix),
-		)
-		globMatches, err := filepath.Glob(globPattern)
-		if err != nil {
-			return fmt.Errorf(
-				"pruneBackups: error looking up matching files using pattern %s: %w",
-				globPattern,
-				err,
-			)
-		}
-
-		var candidates []string
-		for _, candidate := range globMatches {
-			fi, err := os.Lstat(candidate)
-			if err != nil {
-				return fmt.Errorf(
-					"pruneBackups: error calling Lstat on file %s: %w",
-					candidate,
-					err,
-				)
-			}
-
-			if fi.Mode()&os.ModeSymlink != os.ModeSymlink {
-				candidates = append(candidates, candidate)
-			}
-		}
-
-		var matches []string
-		for _, candidate := range candidates {
-			fi, err := os.Stat(candidate)
-			if err != nil {
-				return fmt.Errorf(
-					"pruneBackups: error calling stat on file %s: %w",
-					candidate,
-					err,
-				)
-			}
-			if fi.ModTime().Before(deadline) {
-				matches = append(matches, candidate)
-			}
-		}
-
-		s.stats.Storages.Local = StorageStats{
-			Total:  uint(len(candidates)),
-			Pruned: uint(len(matches)),
-		}
-
-		doPrune(len(matches), len(candidates), "local backup(s)", func() error {
-			var removeErrors []error
-			for _, match := range matches {
-				if err := os.Remove(match); err != nil {
-					removeErrors = append(removeErrors, err)
-				}
-			}
-			if len(removeErrors) != 0 {
-				return fmt.Errorf(
-					"pruneBackups: %d error(s) deleting local files, starting with: %w",
-					len(removeErrors),
-					join(removeErrors...),
-				)
-			}
-			return nil
-		})
-	}
 	return nil
 }

--- a/cmd/backup/stats.go
+++ b/cmd/backup/stats.go
@@ -5,6 +5,7 @@ package main

 import (
 	"bytes"
+	"sync"
 	"time"
 )

@@ -30,20 +31,15 @@ type StorageStats struct {
 	PruneErrors uint
 }

-// StoragesStats stats about each possible archival location (Local, WebDAV, S3)
-type StoragesStats struct {
-	Local  StorageStats
-	WebDAV StorageStats
-	S3     StorageStats
-}
-
 // Stats global stats regarding script execution
 type Stats struct {
+	sync.Mutex
 	StartTime  time.Time
 	EndTime    time.Time
 	TookTime   time.Duration
+	LockedTime time.Duration
 	LogOutput  *bytes.Buffer
 	Containers ContainersStats
 	BackupFile BackupFileStats
-	Storages   StoragesStats
+	Storages   map[string]StorageStats
 }
--- a/cmd/backup/util.go
+++ b/cmd/backup/util.go
@@ -5,68 +5,13 @@ package main

 import (
 	"bytes"
-	"errors"
 	"fmt"
 	"io"
 	"os"
-	"strings"
-
-	"github.com/gofrs/flock"
 )

 var noop = func() error { return nil }

-// lock opens a lockfile at the given location, keeping it locked until the
-// caller invokes the returned release func. When invoked while the file is
-// still locked the function panics.
-func lock(lockfile string) func() error {
-	fileLock := flock.New(lockfile)
-	acquired, err := fileLock.TryLock()
-	if err != nil {
-		panic(err)
-	}
-	if !acquired {
-		panic("unable to acquire file lock")
-	}
-	return fileLock.Unlock
-}
-
-// copy creates a copy of the file located at `dst` at `src`.
-func copyFile(src, dst string) error {
-	in, err := os.Open(src)
-	if err != nil {
-		return err
-	}
-	defer in.Close()
-
-	out, err := os.Create(dst)
-	if err != nil {
-		return err
-	}
-
-	_, err = io.Copy(out, in)
-	if err != nil {
-		out.Close()
-		return err
-	}
-	return out.Close()
-}
-
-// join takes a list of errors and joins them into a single error
-func join(errs ...error) error {
-	if len(errs) == 1 {
-		return errs[0]
-	}
-	var msgs []string
-	for _, err := range errs {
-		if err == nil {
-			continue
-		}
-		msgs = append(msgs, err.Error())
-	}
-	return errors.New("[" + strings.Join(msgs, ", ") + "]")
-}
-
 // remove removes the given file or directory from disk.
 func remove(location string) error {
 	fi, err := os.Lstat(location)
@@ -101,7 +46,7 @@ type bufferingWriter struct {

 func (b *bufferingWriter) Write(p []byte) (n int, err error) {
 	if n, err := b.buf.Write(p); err != nil {
-		return n, fmt.Errorf("bufferingWriter: error writing to buffer: %w", err)
+		return n, fmt.Errorf("(*bufferingWriter).Write: error writing to buffer: %w", err)
 	}
 	return b.writer.Write(p)
 }
--- a/docs/NOTIFICATION-TEMPLATES.md
+++ b/docs/NOTIFICATION-TEMPLATES.md
@@ -13,6 +13,7 @@ Here is a list of all data passed to the template:
  * `StartTime`: time when the script started execution
  * `EndTime`: time when the backup has completed successfully (after pruning)
  * `TookTime`: amount of time it took for the backup to run. (equal to `EndTime - StartTime`)
+  * `LockedTime`: amount of time it took for the backup to acquire the exclusive lock
  * `LogOutput`: full log of the application
  * `Containers`: object containing stats about the docker containers
    * `All`: total number of containers
@@ -24,15 +25,16 @@ Here is a list of all data passed to the template:
    * `FullPath`: full path of the backup file (e.g. `/archive/backup-2022-02-11T01-00-00.tar.gz`)
    * `Size`: size in bytes of the backup file
  * `Storages`: object that holds stats about each storage
-    * `Local`, `S3` or `WebDAV`:
+    * `Local`, `S3`, `WebDAV` or `SSH`:
      * `Total`: total number of backup files
      * `Pruned`: number of backup files that were deleted due to pruning rule
      * `PruneErrors`: number of backup files that were unable to be pruned

 ## Functions

-Some formatting functions are also available:
+Some formatting and helper functions are also available:

 * `formatTime`: formats a time object using [RFC3339](https://datatracker.ietf.org/doc/html/rfc3339) format (e.g. `2022-02-11T01:00:00Z`)
 * `formatBytesBin`: formats an amount of bytes using powers of 1024 (e.g. `7055258` bytes will be `6.7 MiB`) 
 * `formatBytesDec`: formats an amount of bytes using powers of 1000 (e.g. `7055258` bytes will be `7.1 MB`)
+* `env`: returns the value of the environment variable of the given key if set
--- a/entrypoint.sh
+++ b/entrypoint.sh
@@ -13,6 +13,7 @@ if [ ! -d "/etc/dockervolumebackup/conf.d" ]; then
 else
  echo "/etc/dockervolumebackup/conf.d was found, using configuration files from this directory."

+  crontab -r && crontab /dev/null
  for file in /etc/dockervolumebackup/conf.d/*; do
    source $file
    BACKUP_CRON_EXPRESSION="${BACKUP_CRON_EXPRESSION:-@daily}"
@@ -22,4 +23,4 @@ else
 fi

 echo "Starting cron in foreground."
-crond -f -l 8
+crond -f -d 8
--- a/go.mod
+++ b/go.mod
@@ -1,6 +1,6 @@
 module github.com/offen/docker-volume-backup

-go 1.17
+go 1.19

 require (
 	github.com/containrrr/shoutrrr v0.5.2
@@ -11,14 +11,16 @@ require (
 	github.com/leekchan/timeutil v0.0.0-20150802142658-28917288c48d
 	github.com/minio/minio-go/v7 v7.0.16
 	github.com/otiai10/copy v1.7.0
+	github.com/pkg/sftp v1.13.5
 	github.com/sirupsen/logrus v1.8.1
-	github.com/studio-b12/gowebdav v0.0.0-20211109083228-3f8721cd4b6f
-	golang.org/x/crypto v0.0.0-20210817164053-32db794688a5
+	github.com/studio-b12/gowebdav v0.0.0-20220128162035-c7b1ff8a5e62
+	golang.org/x/crypto v0.0.0-20211215153901-e495a2d5b3d3
+	golang.org/x/sync v0.0.0-20220601150217-0de741cfad7f
 )

 require (
-	github.com/Microsoft/go-winio v0.4.17 // indirect
-	github.com/containerd/containerd v1.5.5 // indirect
+	github.com/Microsoft/go-winio v0.5.2 // indirect
+	github.com/containerd/containerd v1.6.6 // indirect
 	github.com/docker/distribution v2.7.1+incompatible // indirect
 	github.com/docker/go-connections v0.4.0 // indirect
 	github.com/docker/go-units v0.4.0 // indirect
@@ -26,33 +28,39 @@ require (
 	github.com/fatih/color v1.10.0 // indirect
 	github.com/fsnotify/fsnotify v1.4.9 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
-	github.com/golang/protobuf v1.5.0 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/google/uuid v1.3.0 // indirect
+	github.com/gorilla/mux v1.7.3 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
-	github.com/klauspost/compress v1.13.6 // indirect
+	github.com/klauspost/compress v1.15.6 // indirect
 	github.com/klauspost/cpuid/v2 v2.0.9 // indirect
+	github.com/kr/fs v0.1.0 // indirect
+	github.com/kr/text v0.2.0 // indirect
 	github.com/mattn/go-colorable v0.1.8 // indirect
 	github.com/mattn/go-isatty v0.0.12 // indirect
 	github.com/minio/md5-simd v1.1.2 // indirect
 	github.com/minio/sha256-simd v1.0.0 // indirect
 	github.com/mitchellh/go-homedir v1.1.0 // indirect
+	github.com/moby/term v0.0.0-20200312100748-672ec06f55cd // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/morikuni/aec v1.0.0 // indirect
+	github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e // indirect
 	github.com/nxadm/tail v1.4.6 // indirect
 	github.com/onsi/ginkgo v1.14.2 // indirect
 	github.com/onsi/gomega v1.10.3 // indirect
 	github.com/opencontainers/go-digest v1.0.0 // indirect
-	github.com/opencontainers/image-spec v1.0.1 // indirect
+	github.com/opencontainers/image-spec v1.0.3-0.20211202183452-c5a74bcca799 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/rs/xid v1.3.0 // indirect
-	golang.org/x/net v0.0.0-20210226172049-e18ecbb05110 // indirect
-	golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1 // indirect
-	golang.org/x/text v0.3.6 // indirect
+	golang.org/x/net v0.0.0-20220607020251-c690dde0001d // indirect
+	golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a // indirect
+	golang.org/x/text v0.3.7 // indirect
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
-	google.golang.org/genproto v0.0.0-20201110150050-8816d57aaa9a // indirect
-	google.golang.org/grpc v1.33.2 // indirect
-	google.golang.org/protobuf v1.26.0 // indirect
+	google.golang.org/genproto v0.0.0-20220602131408-e326c6e8e9c8 // indirect
+	google.golang.org/grpc v1.47.0 // indirect
+	google.golang.org/protobuf v1.28.0 // indirect
+	gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f // indirect
 	gopkg.in/ini.v1 v1.65.0 // indirect
 	gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
--- a/go.sum
+++ b/go.sum
--- a/internal/storage/local/local.go
+++ b/internal/storage/local/local.go
@@ -0,0 +1,160 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
+package local
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path"
+	"path/filepath"
+	"time"
+
+	"github.com/offen/docker-volume-backup/internal/storage"
+	"github.com/offen/docker-volume-backup/internal/utilities"
+)
+
+type localStorage struct {
+	*storage.StorageBackend
+	latestSymlink string
+}
+
+// Config allows configuration of a local storage backend.
+type Config struct {
+	ArchivePath   string
+	LatestSymlink string
+}
+
+// NewStorageBackend creates and initializes a new local storage backend.
+func NewStorageBackend(opts Config, logFunc storage.Log) storage.Backend {
+	return &localStorage{
+		StorageBackend: &storage.StorageBackend{
+			DestinationPath: opts.ArchivePath,
+			Log:             logFunc,
+		},
+		latestSymlink: opts.LatestSymlink,
+	}
+}
+
+// Name return the name of the storage backend
+func (b *localStorage) Name() string {
+	return "Local"
+}
+
+// Copy copies the given file to the local storage backend.
+func (b *localStorage) Copy(file string) error {
+	_, name := path.Split(file)
+
+	if err := copyFile(file, path.Join(b.DestinationPath, name)); err != nil {
+		return fmt.Errorf("(*localStorage).Copy: Error copying file to local archive: %w", err)
+	}
+	b.Log(storage.LogLevelInfo, b.Name(), "Stored copy of backup `%s` in local archive `%s`.", file, b.DestinationPath)
+
+	if b.latestSymlink != "" {
+		symlink := path.Join(b.DestinationPath, b.latestSymlink)
+		if _, err := os.Lstat(symlink); err == nil {
+			os.Remove(symlink)
+		}
+		if err := os.Symlink(name, symlink); err != nil {
+			return fmt.Errorf("(*localStorage).Copy: error creating latest symlink: %w", err)
+		}
+		b.Log(storage.LogLevelInfo, b.Name(), "Created/Updated symlink `%s` for latest backup.", b.latestSymlink)
+	}
+
+	return nil
+}
+
+// Prune rotates away backups according to the configuration and provided deadline for the local storage backend.
+func (b *localStorage) Prune(deadline time.Time, pruningPrefix string) (*storage.PruneStats, error) {
+	globPattern := path.Join(
+		b.DestinationPath,
+		fmt.Sprintf("%s*", pruningPrefix),
+	)
+	globMatches, err := filepath.Glob(globPattern)
+	if err != nil {
+		return nil, fmt.Errorf(
+			"(*localStorage).Prune: Error looking up matching files using pattern %s: %w",
+			globPattern,
+			err,
+		)
+	}
+
+	var candidates []string
+	for _, candidate := range globMatches {
+		fi, err := os.Lstat(candidate)
+		if err != nil {
+			return nil, fmt.Errorf(
+				"(*localStorage).Prune: Error calling Lstat on file %s: %w",
+				candidate,
+				err,
+			)
+		}
+
+		if fi.Mode()&os.ModeSymlink != os.ModeSymlink {
+			candidates = append(candidates, candidate)
+		}
+	}
+
+	var matches []string
+	for _, candidate := range candidates {
+		fi, err := os.Stat(candidate)
+		if err != nil {
+			return nil, fmt.Errorf(
+				"(*localStorage).Prune: Error calling stat on file %s: %w",
+				candidate,
+				err,
+			)
+		}
+		if fi.ModTime().Before(deadline) {
+			matches = append(matches, candidate)
+		}
+	}
+
+	stats := &storage.PruneStats{
+		Total:  uint(len(candidates)),
+		Pruned: uint(len(matches)),
+	}
+
+	if err := b.DoPrune(b.Name(), len(matches), len(candidates), "local backup(s)", func() error {
+		var removeErrors []error
+		for _, match := range matches {
+			if err := os.Remove(match); err != nil {
+				removeErrors = append(removeErrors, err)
+			}
+		}
+		if len(removeErrors) != 0 {
+			return fmt.Errorf(
+				"(*localStorage).Prune: %d error(s) deleting local files, starting with: %w",
+				len(removeErrors),
+				utilities.Join(removeErrors...),
+			)
+		}
+		return nil
+	}); err != nil {
+		return stats, err
+	}
+
+	return stats, nil
+}
+
+// copy creates a copy of the file located at `dst` at `src`.
+func copyFile(src, dst string) error {
+	in, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer in.Close()
+
+	out, err := os.Create(dst)
+	if err != nil {
+		return err
+	}
+
+	_, err = io.Copy(out, in)
+	if err != nil {
+		out.Close()
+		return err
+	}
+	return out.Close()
+}
--- a/internal/storage/s3/s3.go
+++ b/internal/storage/s3/s3.go
@@ -0,0 +1,163 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
+package s3
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"path"
+	"path/filepath"
+	"time"
+
+	"github.com/minio/minio-go/v7"
+	"github.com/minio/minio-go/v7/pkg/credentials"
+	"github.com/offen/docker-volume-backup/internal/storage"
+	"github.com/offen/docker-volume-backup/internal/utilities"
+)
+
+type s3Storage struct {
+	*storage.StorageBackend
+	client       *minio.Client
+	bucket       string
+	storageClass string
+}
+
+// Config contains values that define the configuration of a S3 backend.
+type Config struct {
+	Endpoint         string
+	AccessKeyID      string
+	SecretAccessKey  string
+	IamRoleEndpoint  string
+	EndpointProto    string
+	EndpointInsecure bool
+	RemotePath       string
+	BucketName       string
+	StorageClass     string
+}
+
+// NewStorageBackend creates and initializes a new S3/Minio storage backend.
+func NewStorageBackend(opts Config, logFunc storage.Log) (storage.Backend, error) {
+
+	var creds *credentials.Credentials
+	if opts.AccessKeyID != "" && opts.SecretAccessKey != "" {
+		creds = credentials.NewStaticV4(
+			opts.AccessKeyID,
+			opts.SecretAccessKey,
+			"",
+		)
+	} else if opts.IamRoleEndpoint != "" {
+		creds = credentials.NewIAM(opts.IamRoleEndpoint)
+	} else {
+		return nil, errors.New("NewStorageBackend: AWS_S3_BUCKET_NAME is defined, but no credentials were provided")
+	}
+
+	options := minio.Options{
+		Creds:  creds,
+		Secure: opts.EndpointProto == "https",
+	}
+
+	if opts.EndpointInsecure {
+		if !options.Secure {
+			return nil, errors.New("NewStorageBackend: AWS_ENDPOINT_INSECURE = true is only meaningful for https")
+		}
+
+		transport, err := minio.DefaultTransport(true)
+		if err != nil {
+			return nil, fmt.Errorf("NewStorageBackend: failed to create default minio transport: %w", err)
+		}
+		transport.TLSClientConfig.InsecureSkipVerify = true
+		options.Transport = transport
+	}
+
+	mc, err := minio.New(opts.Endpoint, &options)
+	if err != nil {
+		return nil, fmt.Errorf("NewStorageBackend: error setting up minio client: %w", err)
+	}
+
+	return &s3Storage{
+		StorageBackend: &storage.StorageBackend{
+			DestinationPath: opts.RemotePath,
+			Log:             logFunc,
+		},
+		client:       mc,
+		bucket:       opts.BucketName,
+		storageClass: opts.StorageClass,
+	}, nil
+}
+
+// Name returns the name of the storage backend
+func (v *s3Storage) Name() string {
+	return "S3"
+}
+
+// Copy copies the given file to the S3/Minio storage backend.
+func (b *s3Storage) Copy(file string) error {
+	_, name := path.Split(file)
+
+	if _, err := b.client.FPutObject(context.Background(), b.bucket, filepath.Join(b.DestinationPath, name), file, minio.PutObjectOptions{
+		ContentType:  "application/tar+gzip",
+		StorageClass: b.storageClass,
+	}); err != nil {
+		errResp := minio.ToErrorResponse(err)
+		return fmt.Errorf("(*s3Storage).Copy: error uploading backup to remote storage: [Message]: '%s', [Code]: %s, [StatusCode]: %d", errResp.Message, errResp.Code, errResp.StatusCode)
+	}
+	b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup `%s` to bucket `%s`.", file, b.bucket)
+
+	return nil
+}
+
+// Prune rotates away backups according to the configuration and provided deadline for the S3/Minio storage backend.
+func (b *s3Storage) Prune(deadline time.Time, pruningPrefix string) (*storage.PruneStats, error) {
+	candidates := b.client.ListObjects(context.Background(), b.bucket, minio.ListObjectsOptions{
+		WithMetadata: true,
+		Prefix:       filepath.Join(b.DestinationPath, pruningPrefix),
+		Recursive:    true,
+	})
+
+	var matches []minio.ObjectInfo
+	var lenCandidates int
+	for candidate := range candidates {
+		lenCandidates++
+		if candidate.Err != nil {
+			return nil, fmt.Errorf(
+				"(*s3Storage).Prune: Error looking up candidates from remote storage! %w",
+				candidate.Err,
+			)
+		}
+		if candidate.LastModified.Before(deadline) {
+			matches = append(matches, candidate)
+		}
+	}
+
+	stats := &storage.PruneStats{
+		Total:  uint(lenCandidates),
+		Pruned: uint(len(matches)),
+	}
+
+	if err := b.DoPrune(b.Name(), len(matches), lenCandidates, "remote backup(s)", func() error {
+		objectsCh := make(chan minio.ObjectInfo)
+		go func() {
+			for _, match := range matches {
+				objectsCh <- match
+			}
+			close(objectsCh)
+		}()
+		errChan := b.client.RemoveObjects(context.Background(), b.bucket, objectsCh, minio.RemoveObjectsOptions{})
+		var removeErrors []error
+		for result := range errChan {
+			if result.Err != nil {
+				removeErrors = append(removeErrors, result.Err)
+			}
+		}
+		if len(removeErrors) != 0 {
+			return utilities.Join(removeErrors...)
+		}
+		return nil
+	}); err != nil {
+		return stats, err
+	}
+
+	return stats, nil
+}
--- a/internal/storage/ssh/ssh.go
+++ b/internal/storage/ssh/ssh.go
@@ -0,0 +1,190 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
+package ssh
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/offen/docker-volume-backup/internal/storage"
+	"github.com/pkg/sftp"
+	"golang.org/x/crypto/ssh"
+)
+
+type sshStorage struct {
+	*storage.StorageBackend
+	client     *ssh.Client
+	sftpClient *sftp.Client
+	hostName   string
+}
+
+// Config allows to configure a SSH backend.
+type Config struct {
+	HostName           string
+	Port               string
+	User               string
+	Password           string
+	IdentityFile       string
+	IdentityPassphrase string
+	RemotePath         string
+}
+
+// NewStorageBackend creates and initializes a new SSH storage backend.
+func NewStorageBackend(opts Config, logFunc storage.Log) (storage.Backend, error) {
+	var authMethods []ssh.AuthMethod
+
+	if opts.Password != "" {
+		authMethods = append(authMethods, ssh.Password(opts.Password))
+	}
+
+	if _, err := os.Stat(opts.IdentityFile); err == nil {
+		key, err := ioutil.ReadFile(opts.IdentityFile)
+		if err != nil {
+			return nil, errors.New("NewStorageBackend: error reading the private key")
+		}
+
+		var signer ssh.Signer
+		if opts.IdentityPassphrase != "" {
+			signer, err = ssh.ParsePrivateKeyWithPassphrase(key, []byte(opts.IdentityPassphrase))
+			if err != nil {
+				return nil, errors.New("NewStorageBackend: error parsing the encrypted private key")
+			}
+			authMethods = append(authMethods, ssh.PublicKeys(signer))
+		} else {
+			signer, err = ssh.ParsePrivateKey(key)
+			if err != nil {
+				return nil, errors.New("NewStorageBackend: error parsing the private key")
+			}
+			authMethods = append(authMethods, ssh.PublicKeys(signer))
+		}
+	}
+
+	sshClientConfig := &ssh.ClientConfig{
+		User:            opts.User,
+		Auth:            authMethods,
+		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
+	}
+	sshClient, err := ssh.Dial("tcp", fmt.Sprintf("%s:%s", opts.HostName, opts.Port), sshClientConfig)
+
+	if err != nil {
+		return nil, fmt.Errorf("NewStorageBackend: Error creating ssh client: %w", err)
+	}
+	_, _, err = sshClient.SendRequest("keepalive", false, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	sftpClient, err := sftp.NewClient(sshClient)
+	if err != nil {
+		return nil, fmt.Errorf("NewStorageBackend: error creating sftp client: %w", err)
+	}
+
+	return &sshStorage{
+		StorageBackend: &storage.StorageBackend{
+			DestinationPath: opts.RemotePath,
+			Log:             logFunc,
+		},
+		client:     sshClient,
+		sftpClient: sftpClient,
+		hostName:   opts.HostName,
+	}, nil
+}
+
+// Name returns the name of the storage backend
+func (b *sshStorage) Name() string {
+	return "SSH"
+}
+
+// Copy copies the given file to the SSH storage backend.
+func (b *sshStorage) Copy(file string) error {
+	source, err := os.Open(file)
+	_, name := path.Split(file)
+	if err != nil {
+		return fmt.Errorf("(*sshStorage).Copy: Error reading the file to be uploaded: %w", err)
+	}
+	defer source.Close()
+
+	destination, err := b.sftpClient.Create(filepath.Join(b.DestinationPath, name))
+	if err != nil {
+		return fmt.Errorf("(*sshStorage).Copy: Error creating file on SSH storage: %w", err)
+	}
+	defer destination.Close()
+
+	chunk := make([]byte, 1000000)
+	for {
+		num, err := source.Read(chunk)
+		if err == io.EOF {
+			tot, err := destination.Write(chunk[:num])
+			if err != nil {
+				return fmt.Errorf("(*sshStorage).Copy: Error uploading the file to SSH storage: %w", err)
+			}
+
+			if tot != len(chunk[:num]) {
+				return errors.New("(*sshStorage).Copy: failed to write stream")
+			}
+
+			break
+		}
+
+		if err != nil {
+			return fmt.Errorf("(*sshStorage).Copy: Error uploading the file to SSH storage: %w", err)
+		}
+
+		tot, err := destination.Write(chunk[:num])
+		if err != nil {
+			return fmt.Errorf("(*sshStorage).Copy: Error uploading the file to SSH storage: %w", err)
+		}
+
+		if tot != len(chunk[:num]) {
+			return fmt.Errorf("(*sshStorage).Copy: failed to write stream")
+		}
+	}
+
+	b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup `%s` to SSH storage '%s' at path '%s'.", file, b.hostName, b.DestinationPath)
+
+	return nil
+}
+
+// Prune rotates away backups according to the configuration and provided deadline for the SSH storage backend.
+func (b *sshStorage) Prune(deadline time.Time, pruningPrefix string) (*storage.PruneStats, error) {
+	candidates, err := b.sftpClient.ReadDir(b.DestinationPath)
+	if err != nil {
+		return nil, fmt.Errorf("(*sshStorage).Prune: Error reading directory from SSH storage: %w", err)
+	}
+
+	var matches []string
+	for _, candidate := range candidates {
+		if !strings.HasPrefix(candidate.Name(), pruningPrefix) {
+			continue
+		}
+		if candidate.ModTime().Before(deadline) {
+			matches = append(matches, candidate.Name())
+		}
+	}
+
+	stats := &storage.PruneStats{
+		Total:  uint(len(candidates)),
+		Pruned: uint(len(matches)),
+	}
+
+	if err := b.DoPrune(b.Name(), len(matches), len(candidates), "SSH backup(s)", func() error {
+		for _, match := range matches {
+			if err := b.sftpClient.Remove(filepath.Join(b.DestinationPath, match)); err != nil {
+				return fmt.Errorf("(*sshStorage).Prune: Error removing file from SSH storage: %w", err)
+			}
+		}
+		return nil
+	}); err != nil {
+		return stats, err
+	}
+
+	return stats, nil
+}
--- a/internal/storage/storage.go
+++ b/internal/storage/storage.go
@@ -0,0 +1,61 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
+package storage
+
+import (
+	"time"
+)
+
+// Backend is an interface for defining functions which all storage providers support.
+type Backend interface {
+	Copy(file string) error
+	Prune(deadline time.Time, pruningPrefix string) (*PruneStats, error)
+	Name() string
+}
+
+// StorageBackend is a generic type of storage. Everything here are common properties of all storage types.
+type StorageBackend struct {
+	DestinationPath string
+	RetentionDays   int
+	Log             Log
+}
+
+type LogLevel int
+
+const (
+	LogLevelInfo LogLevel = iota
+	LogLevelWarning
+	LogLevelError
+)
+
+type Log func(logType LogLevel, context string, msg string, params ...interface{})
+
+// PruneStats is a wrapper struct for returning stats after pruning
+type PruneStats struct {
+	Total  uint
+	Pruned uint
+}
+
+// DoPrune holds general control flow that applies to any kind of storage.
+// Callers can pass in a thunk that performs the actual deletion of files.
+func (b *StorageBackend) DoPrune(context string, lenMatches, lenCandidates int, description string, doRemoveFiles func() error) error {
+	if lenMatches != 0 && lenMatches != lenCandidates {
+		if err := doRemoveFiles(); err != nil {
+			return err
+		}
+		b.Log(LogLevelInfo, context,
+			"Pruned %d out of %d %s as their age exceeded the configured retention period of %d days.",
+			lenMatches,
+			lenCandidates,
+			description,
+			b.RetentionDays,
+		)
+	} else if lenMatches != 0 && lenMatches == lenCandidates {
+		b.Log(LogLevelWarning, context, "The current configuration would delete all %d existing %s.", lenMatches, description)
+		b.Log(LogLevelWarning, context, "Refusing to do so, please check your configuration.")
+	} else {
+		b.Log(LogLevelInfo, context, "None of %d existing %s were pruned.", lenCandidates, description)
+	}
+	return nil
+}
--- a/internal/storage/webdav/webdav.go
+++ b/internal/storage/webdav/webdav.go
@@ -0,0 +1,121 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
+package webdav
+
+import (
+	"errors"
+	"fmt"
+	"io/fs"
+	"net/http"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/offen/docker-volume-backup/internal/storage"
+	"github.com/studio-b12/gowebdav"
+)
+
+type webDavStorage struct {
+	*storage.StorageBackend
+	client *gowebdav.Client
+	url    string
+}
+
+// Config allows to configure a WebDAV storage backend.
+type Config struct {
+	URL         string
+	RemotePath  string
+	Username    string
+	Password    string
+	URLInsecure bool
+}
+
+// NewStorageBackend creates and initializes a new WebDav storage backend.
+func NewStorageBackend(opts Config, logFunc storage.Log) (storage.Backend, error) {
+	if opts.Username == "" || opts.Password == "" {
+		return nil, errors.New("NewStorageBackend: WEBDAV_URL is defined, but no credentials were provided")
+	} else {
+		webdavClient := gowebdav.NewClient(opts.URL, opts.Username, opts.Password)
+
+		if opts.URLInsecure {
+			defaultTransport, ok := http.DefaultTransport.(*http.Transport)
+			if !ok {
+				return nil, errors.New("NewStorageBackend: unexpected error when asserting type for http.DefaultTransport")
+			}
+			webdavTransport := defaultTransport.Clone()
+			webdavTransport.TLSClientConfig.InsecureSkipVerify = opts.URLInsecure
+			webdavClient.SetTransport(webdavTransport)
+		}
+
+		return &webDavStorage{
+			StorageBackend: &storage.StorageBackend{
+				DestinationPath: opts.RemotePath,
+				Log:             logFunc,
+			},
+			client: webdavClient,
+		}, nil
+	}
+}
+
+// Name returns the name of the storage backend
+func (b *webDavStorage) Name() string {
+	return "WebDAV"
+}
+
+// Copy copies the given file to the WebDav storage backend.
+func (b *webDavStorage) Copy(file string) error {
+	bytes, err := os.ReadFile(file)
+	_, name := path.Split(file)
+	if err != nil {
+		return fmt.Errorf("(*webDavStorage).Copy: Error reading the file to be uploaded: %w", err)
+	}
+	if err := b.client.MkdirAll(b.DestinationPath, 0644); err != nil {
+		return fmt.Errorf("(*webDavStorage).Copy: Error creating directory '%s' on WebDAV server: %w", b.DestinationPath, err)
+	}
+	if err := b.client.Write(filepath.Join(b.DestinationPath, name), bytes, 0644); err != nil {
+		return fmt.Errorf("(*webDavStorage).Copy: Error uploading the file to WebDAV server: %w", err)
+	}
+	b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup '%s' to WebDAV URL '%s' at path '%s'.", file, b.url, b.DestinationPath)
+
+	return nil
+}
+
+// Prune rotates away backups according to the configuration and provided deadline for the WebDav storage backend.
+func (b *webDavStorage) Prune(deadline time.Time, pruningPrefix string) (*storage.PruneStats, error) {
+	candidates, err := b.client.ReadDir(b.DestinationPath)
+	if err != nil {
+		return nil, fmt.Errorf("(*webDavStorage).Prune: Error looking up candidates from remote storage: %w", err)
+	}
+	var matches []fs.FileInfo
+	var lenCandidates int
+	for _, candidate := range candidates {
+		if !strings.HasPrefix(candidate.Name(), pruningPrefix) {
+			continue
+		}
+		lenCandidates++
+		if candidate.ModTime().Before(deadline) {
+			matches = append(matches, candidate)
+		}
+	}
+
+	stats := &storage.PruneStats{
+		Total:  uint(lenCandidates),
+		Pruned: uint(len(matches)),
+	}
+
+	if err := b.DoPrune(b.Name(), len(matches), lenCandidates, "WebDAV backup(s)", func() error {
+		for _, match := range matches {
+			if err := b.client.Remove(filepath.Join(b.DestinationPath, match.Name())); err != nil {
+				return fmt.Errorf("(*webDavStorage).Prune: Error removing file from WebDAV storage: %w", err)
+			}
+		}
+		return nil
+	}); err != nil {
+		return stats, err
+	}
+
+	return stats, nil
+}
--- a/internal/utilities/util.go
+++ b/internal/utilities/util.go
@@ -0,0 +1,24 @@
+// Copyright 2022 - Offen Authors <hioffen@posteo.de>
+// SPDX-License-Identifier: MPL-2.0
+
+package utilities
+
+import (
+	"errors"
+	"strings"
+)
+
+// Join takes a list of errors and joins them into a single error
+func Join(errs ...error) error {
+	if len(errs) == 1 {
+		return errs[0]
+	}
+	var msgs []string
+	for _, err := range errs {
+		if err == nil {
+			continue
+		}
+		msgs = append(msgs, err.Error())
+	}
+	return errors.New("[" + strings.Join(msgs, ", ") + "]")
+}
--- a/test/cli/run.sh
+++ b/test/cli/run.sh
@@ -3,6 +3,8 @@
 set -e

 cd $(dirname $0)
+. ../util.sh
+current_test=$(basename $(pwd))

 docker network create test_network
 docker volume create backup_data
@@ -50,17 +52,11 @@ docker run --rm -it \
  -v backup_data:/data alpine \
  ash -c 'tar -xvf /data/backup/test.tar.gz && test -f /backup/app_data/offen.db && test -d /backup/empty_data'

-echo "[TEST:PASS] Found relevant files in untared remote backup."
+pass "Found relevant files in untared remote backup."

 # This test does not stop containers during backup. This is happening on
 # purpose in order to cover this setup as well.
-if [ "$(docker ps -q | wc -l)" != "2" ]; then
-  echo "[TEST:FAIL] Expected all containers to be running post backup, instead seen:"
-  docker ps
-  exit 1
-fi
-
-echo "[TEST:PASS] All containers running post backup."
+expect_running_containers "2"

 docker rm $(docker stop minio offen)
 docker volume rm backup_data app_data
--- a/test/commands/docker-compose.yml
+++ b/test/commands/docker-compose.yml
@@ -10,12 +10,27 @@ services:
      MARIADB_ROOT_PASSWORD: test
      MARIADB_DATABASE: backup
    labels:
+      # this is testing the deprecated label on purpose
      - docker-volume-backup.exec-pre=/bin/sh -c 'mysqldump -ptest --all-databases > /tmp/volume/dump.sql'
-      - docker-volume-backup.exec-post=/bin/sh -c 'echo "post" > /tmp/volume/post.txt'
+      - docker-volume-backup.copy-post=/bin/sh -c 'echo "post" > /tmp/volume/post.txt'
      - docker-volume-backup.exec-label=test
    volumes:
      - app_data:/tmp/volume

+  other_database:
+    image: mariadb:10.7
+    deploy:
+      restart_policy:
+        condition: on-failure
+    environment:
+      MARIADB_ROOT_PASSWORD: test
+      MARIADB_DATABASE: backup
+    labels:
+      - docker-volume-backup.archive-pre=touch /tmp/volume/not-relevant.txt
+      - docker-volume-backup.exec-label=not-relevant
+    volumes:
+      - app_data:/tmp/volume
+
  backup:
    image: offen/docker-volume-backup:${TEST_VERSION:-canary}
    deploy:
--- a/test/commands/run.sh
+++ b/test/commands/run.sh
@@ -3,7 +3,8 @@
 set -e

 cd $(dirname $0)
-
+. ../util.sh
+current_test=$(basename $(pwd))

 docker-compose up -d
 sleep 30 # mariadb likes to take a bit before responding
@@ -13,29 +14,32 @@ sudo cp -r $(docker volume inspect --format='{{ .Mountpoint }}' commands_archive

 tar -xvf ./local/test.tar.gz
 if [ ! -f ./backup/data/dump.sql ]; then
-  echo "[TEST:FAIL] Could not find file written by pre command."
-  exit 1
+  fail "Could not find file written by pre command."
 fi
-echo "[TEST:PASS] Found expected file."
+pass "Found expected file."
+
+if [ -f ./backup/data/not-relevant.txt ]; then
+  fail "Command ran for container with other label."
+fi
+pass "Command did not run for container with other label."

 if [ -f ./backup/data/post.txt ]; then
-  echo "[TEST:FAIL] File created in post command was present in backup."
-  exit 1
+  fail "File created in post command was present in backup."
 fi
-echo "[TEST:PASS] Did not find unexpected file."
+pass "Did not find unexpected file."

 docker-compose down --volumes
 sudo rm -rf ./local


-echo "[TEST:INFO] Running commands test in swarm mode next."
+info "Running commands test in swarm mode next."

 docker swarm init

 docker stack deploy --compose-file=docker-compose.yml test_stack

 while [ -z $(docker ps -q -f name=backup) ]; do
-  echo "[TEST:INFO] Backup container not ready yet. Retrying."
+  info "Backup container not ready yet. Retrying."
  sleep 1
 done

@@ -47,16 +51,14 @@ sudo cp -r $(docker volume inspect --format='{{ .Mountpoint }}' test_stack_archi

 tar -xvf ./local/test.tar.gz
 if [ ! -f ./backup/data/dump.sql ]; then
-  echo "[TEST:FAIL] Could not find file written by pre command."
-  exit 1
+  fail "Could not find file written by pre command."
 fi
-echo "[TEST:PASS] Found expected file."
+pass "Found expected file."

 if [ -f ./backup/data/post.txt ]; then
-  echo "[TEST:FAIL] File created in post command was present in backup."
-  exit 1
+  fail "File created in post command was present in backup."
 fi
-echo "[TEST:PASS] Did not find unexpected file."
+pass "Did not find unexpected file."

 docker stack rm test_stack
 docker swarm leave --force
--- a/test/compose/run.sh
+++ b/test/compose/run.sh
@@ -1,68 +0,0 @@
-#!/bin/sh
-
-set -e
-
-cd $(dirname $0)
-
-mkdir -p local
-
-docker-compose up -d
-sleep 5
-
-# A symlink for a known file in the volume is created so the test can check
-# whether symlinks are preserved on backup.
-docker-compose exec offen ln -s /var/opt/offen/offen.db /var/opt/offen/db.link
-docker-compose exec backup backup
-
-sleep 5
-if [ "$(docker-compose ps -q | wc -l)" != "4" ]; then
-  echo "[TEST:FAIL] Expected all containers to be running post backup, instead seen:"
-  docker-compose ps
-  exit 1
-fi
-echo "[TEST:PASS] All containers running post backup."
-
-
-docker run --rm -it \
-  -v compose_minio_backup_data:/minio_data \
-  -v compose_webdav_backup_data:/webdav_data alpine \
-  ash -c 'apk add gnupg && \
-          echo 1234secret | gpg -d --pinentry-mode loopback --passphrase-fd 0 --yes /minio_data/backup/test-hostnametoken.tar.gz.gpg > /tmp/test-hostnametoken.tar.gz && tar -xvf /tmp/test-hostnametoken.tar.gz -C /tmp && test -f /tmp/backup/app_data/offen.db && \
-          echo 1234secret | gpg -d --pinentry-mode loopback --passphrase-fd 0 --yes /webdav_data/data/my/new/path/test-hostnametoken.tar.gz.gpg > /tmp/test-hostnametoken.tar.gz && tar -xvf /tmp/test-hostnametoken.tar.gz -C /tmp && test -f /tmp/backup/app_data/offen.db'
-
-echo "[TEST:PASS] Found relevant files in decrypted and untared remote backups."
-
-echo 1234secret | gpg -d --pinentry-mode loopback --yes --passphrase-fd 0 ./local/test-hostnametoken.tar.gz.gpg > ./local/decrypted.tar.gz
-tar -xf ./local/decrypted.tar.gz -C /tmp && test -f /tmp/backup/app_data/offen.db
-rm ./local/decrypted.tar.gz
-test -L /tmp/backup/app_data/db.link
-
-echo "[TEST:PASS] Found relevant files in decrypted and untared local backup."
-
-test -L ./local/test-hostnametoken.latest.tar.gz.gpg
-echo "[TEST:PASS] Found symlink to latest version in local backup."
-
-# The second part of this test checks if backups get deleted when the retention
-# is set to 0 days (which it should not as it would mean all backups get deleted)
-# TODO: find out if we can test actual deletion without having to wait for a day
-BACKUP_RETENTION_DAYS="0" docker-compose up -d
-sleep 5
-
-docker-compose exec backup backup
-
-docker run --rm -it \
-  -v compose_minio_backup_data:/minio_data \
-  -v compose_webdav_backup_data:/webdav_data alpine \
-  ash -c '[ $(find /minio_data/backup/ -type f | wc -l) = "1" ] && \
-          [ $(find /webdav_data/data/my/new/path/ -type f | wc -l) = "1" ]'
-
-echo "[TEST:PASS] Remote backups have not been deleted."
-
-if [ "$(find ./local -type f | wc -l)" != "1" ]; then
-  echo "[TEST:FAIL] Backups should not have been deleted, instead seen:"
-  find ./local -type f
-  exit 1
-fi
-echo "[TEST:PASS] Local backups have not been deleted."
-
-docker-compose down --volumes
--- a/test/confd/01backup.env
+++ b/test/confd/01backup.env
--- a/test/confd/02backup.env
+++ b/test/confd/02backup.env
@@ -0,0 +1,2 @@
+BACKUP_FILENAME="other.tar.gz"
+BACKUP_CRON_EXPRESSION="*/1 * * * *"
--- a/test/confd/03never.env
+++ b/test/confd/03never.env
--- a/test/confd/docker-compose.yml
+++ b/test/confd/docker-compose.yml
@@ -7,8 +7,9 @@ services:
    volumes:
      - ./local:/archive
      - app_data:/backup/app_data:ro
-      - ./backup.env:/etc/dockervolumebackup/conf.d/00backup.env
-      - ./never.env:/etc/dockervolumebackup/conf.d/10never.env
+      - ./01backup.env:/etc/dockervolumebackup/conf.d/01backup.env
+      - ./02backup.env:/etc/dockervolumebackup/conf.d/02backup.env
+      - ./03never.env:/etc/dockervolumebackup/conf.d/03never.env
      - /var/run/docker.sock:/var/run/docker.sock

  offen:
--- a/test/confd/run.sh
+++ b/test/confd/run.sh
@@ -3,6 +3,8 @@
 set -e

 cd $(dirname $0)
+. ../util.sh
+current_test=$(basename $(pwd))

 mkdir -p local

@@ -14,13 +16,16 @@ sleep 100
 docker-compose down --volumes

 if [ ! -f ./local/conf.tar.gz ]; then
-  echo "[TEST:FAIL] Config from file was not used."
-  exit 1
+  fail "Config from file was not used."
 fi
-echo "[TEST:PASS] Config from file was used."
+pass "Config from file was used."
+
+if [ ! -f ./local/other.tar.gz ]; then
+  fail "Run on same schedule did not succeed."
+fi
+pass "Run on same schedule succeeded."

 if [ -f ./local/never.tar.gz ]; then
-  echo "[TEST:FAIL] Unexpected file was found."
-  exit 1
+  fail "Unexpected file was found."
 fi
-echo "[TEST:PASS] Unexpected cron did not run."
+pass "Unexpected cron did not run."
--- a/test/compose/.gitignore
+++ b/test/compose/.gitignore
--- a/test/gpg/docker-compose.yml
+++ b/test/gpg/docker-compose.yml
@@ -0,0 +1,26 @@
+version: '3'
+
+services:
+  backup:
+    image: offen/docker-volume-backup:${TEST_VERSION:-canary}
+    restart: always
+    environment:
+      BACKUP_CRON_EXPRESSION: 0 0 5 31 2 ?
+      BACKUP_FILENAME: test.tar.gz
+      BACKUP_LATEST_SYMLINK: test-latest.tar.gz.gpg
+      BACKUP_RETENTION_DAYS: ${BACKUP_RETENTION_DAYS:-7}
+      GPG_PASSPHRASE: 1234secret
+    volumes:
+      - ./local:/archive
+      - app_data:/backup/app_data:ro
+      - /var/run/docker.sock:/var/run/docker.sock
+
+  offen:
+    image: offen/offen:latest
+    labels:
+      - docker-volume-backup.stop-during-backup=true
+    volumes:
+      - app_data:/var/opt/offen
+
+volumes:
+  app_data:
--- a/test/gpg/run.sh
+++ b/test/gpg/run.sh
@@ -0,0 +1,34 @@
+#!/bin/sh
+
+set -e
+
+cd "$(dirname "$0")"
+. ../util.sh
+current_test=$(basename $(pwd))
+
+mkdir -p local
+
+docker-compose up -d
+sleep 5
+
+docker-compose exec backup backup
+
+expect_running_containers "2"
+
+tmp_dir=$(mktemp -d)
+
+echo 1234secret | gpg -d --pinentry-mode loopback --yes --passphrase-fd 0 ./local/test.tar.gz.gpg > ./local/decrypted.tar.gz
+tar -xf ./local/decrypted.tar.gz -C $tmp_dir
+ls -lah $tmp_dir
+if [ ! -f $tmp_dir/backup/app_data/offen.db ]; then
+  fail "Could not find expected file in untared archive."
+fi
+rm ./local/decrypted.tar.gz
+
+pass "Found relevant files in decrypted and untared local backup."
+
+if [ ! -L ./local/test-latest.tar.gz.gpg ]; then
+  fail "Could not find local symlink to latest encrypted backup."
+fi
+
+docker-compose down --volumes
--- a/test/ignore/.gitignore
+++ b/test/ignore/.gitignore
@@ -0,0 +1 @@
+local
--- a/test/ignore/docker-compose.yml
+++ b/test/ignore/docker-compose.yml
@@ -0,0 +1,15 @@
+version: '3.8'
+
+services:
+  backup:
+    image: offen/docker-volume-backup:${TEST_VERSION:-canary}
+    deploy:
+      restart_policy:
+        condition: on-failure
+    environment:
+      BACKUP_FILENAME: test.tar.gz
+      BACKUP_CRON_EXPRESSION: 0 0 5 31 2 ?
+      BACKUP_EXCLUDE_REGEXP: '\.(me|you)$$'
+    volumes:
+      - ./local:/archive
+      - ./sources:/backup/data:ro
--- a/test/ignore/run.sh
+++ b/test/ignore/run.sh
@@ -0,0 +1,28 @@
+#!/bin/sh
+
+set -e
+
+cd $(dirname $0)
+. ../util.sh
+current_test=$(basename $(pwd))
+
+mkdir -p local
+
+docker-compose up -d
+sleep 5
+docker-compose exec backup backup
+
+docker-compose down --volumes
+
+out=$(mktemp -d)
+sudo tar --same-owner -xvf ./local/test.tar.gz -C "$out"
+
+if [ ! -f "$out/backup/data/me.txt" ]; then
+  fail "Expected file was not found."
+fi
+pass "Expected file was found."
+
+if [ -f "$out/backup/data/skip.me" ]; then
+  fail "Ignored file was found."
+fi
+pass "Ignored file was not found."
--- a/test/ignore/sources/me.txt
+++ b/test/ignore/sources/me.txt
--- a/test/ignore/sources/skip.me
+++ b/test/ignore/sources/skip.me
--- a/test/local/.gitignore
+++ b/test/local/.gitignore
@@ -0,0 +1 @@
+local
--- a/test/local/docker-compose.yml
+++ b/test/local/docker-compose.yml
@@ -0,0 +1,29 @@
+version: '3'
+
+services:
+  backup:
+    image: offen/docker-volume-backup:${TEST_VERSION:-canary}
+    hostname: hostnametoken
+    restart: always
+    environment:
+      BACKUP_FILENAME_EXPAND: 'true'
+      BACKUP_FILENAME: test-$$HOSTNAME.tar.gz
+      BACKUP_LATEST_SYMLINK: test-$$HOSTNAME.latest.tar.gz.gpg
+      BACKUP_CRON_EXPRESSION: 0 0 5 31 2 ?
+      BACKUP_RETENTION_DAYS: ${BACKUP_RETENTION_DAYS:-7}
+      BACKUP_PRUNING_LEEWAY: 5s
+      BACKUP_PRUNING_PREFIX: test
+    volumes:
+      - app_data:/backup/app_data:ro
+      - /var/run/docker.sock:/var/run/docker.sock
+      - ./local:/archive
+
+  offen:
+    image: offen/offen:latest
+    labels:
+      - docker-volume-backup.stop-during-backup=true
+    volumes:
+      - app_data:/var/opt/offen
+
+volumes:
+  app_data:
--- a/test/local/run.sh
+++ b/test/local/run.sh
@@ -0,0 +1,55 @@
+#!/bin/sh
+
+set -e
+
+cd "$(dirname "$0")"
+. ../util.sh
+current_test=$(basename $(pwd))
+
+mkdir -p local
+
+docker-compose up -d
+sleep 5
+
+# A symlink for a known file in the volume is created so the test can check
+# whether symlinks are preserved on backup.
+docker-compose exec offen ln -s /var/opt/offen/offen.db /var/opt/offen/db.link
+docker-compose exec backup backup
+
+sleep 5
+
+expect_running_containers "2"
+
+tmp_dir=$(mktemp -d)
+tar -xvf ./local/test-hostnametoken.tar.gz -C $tmp_dir
+if [ ! -f "$tmp_dir/backup/app_data/offen.db" ]; then
+  fail "Could not find expected file in untared archive."
+fi
+rm -f ./local/test-hostnametoken.tar.gz
+
+if [ ! -L "$tmp_dir/backup/app_data/db.link" ]; then
+  fail "Could not find expected symlink in untared archive."
+fi
+
+pass "Found relevant files in decrypted and untared local backup."
+
+if [ ! -L ./local/test-hostnametoken.latest.tar.gz.gpg ]; then
+  fail "Could not find symlink to latest version."
+fi
+
+pass "Found symlink to latest version in local backup."
+
+# The second part of this test checks if backups get deleted when the retention
+# is set to 0 days (which it should not as it would mean all backups get deleted)
+# TODO: find out if we can test actual deletion without having to wait for a day
+BACKUP_RETENTION_DAYS="0" docker-compose up -d
+sleep 5
+
+docker-compose exec backup backup
+
+if [ "$(find ./local -type f | wc -l)" != "1" ]; then
+  fail "Backups should not have been deleted, instead seen: "$(find ./local -type f)""
+fi
+pass "Local backups have not been deleted."
+
+docker-compose down --volumes
--- a/test/notifications/docker-compose.yml
+++ b/test/notifications/docker-compose.yml
@@ -10,6 +10,7 @@ services:
      BACKUP_PRUNING_PREFIX: test
      NOTIFICATION_LEVEL: info
      NOTIFICATION_URLS: ${NOTIFICATION_URLS}
+      EXTRA_VALUE: extra-value
    volumes:
      - ./local:/archive
      - app_data:/backup/app_data:ro
--- a/test/notifications/notifications.tmpl
+++ b/test/notifications/notifications.tmpl
@@ -1,5 +1,5 @@
 {{ define "title_success" -}}
-Successful test run, yay!
+Successful test run with {{ env "EXTRA_VALUE" }}, yay!
 {{- end }}

 {{ define "body_success" -}}
--- a/test/notifications/run.sh
+++ b/test/notifications/run.sh
@@ -3,6 +3,8 @@
 set -e

 cd $(dirname $0)
+. ../util.sh
+current_test=$(basename $(pwd))

 mkdir -p local

@@ -10,16 +12,15 @@ docker-compose up -d
 sleep 5

 GOTIFY_TOKEN=$(curl -sSLX POST -H 'Content-Type: application/json' -d '{"name":"test"}' http://admin:custom@localhost:8080/application | jq -r '.token')
-echo "[TEST:INFO] Set up Gotify application using token $GOTIFY_TOKEN"
+info "Set up Gotify application using token $GOTIFY_TOKEN"

 docker-compose exec backup backup

 NUM_MESSAGES=$(curl -sSL http://admin:custom@localhost:8080/message | jq -r '.messages | length')
 if [ "$NUM_MESSAGES" != 0 ]; then
-  echo "[TEST:FAIL] Expected no notifications to be sent when not configured"
-  exit 1
+  fail "Expected no notifications to be sent when not configured"
 fi
-echo "[TEST:PASS] No notifications were sent when not configured."
+pass "No notifications were sent when not configured."

 docker-compose down

@@ -29,24 +30,21 @@ docker-compose exec backup backup

 NUM_MESSAGES=$(curl -sSL http://admin:custom@localhost:8080/message | jq -r '.messages | length')
 if [ "$NUM_MESSAGES" != 1 ]; then
-  echo "[TEST:FAIL] Expected one notifications to be sent when configured"
-  exit 1
+  fail "Expected one notifications to be sent when configured"
 fi
-echo "[TEST:PASS] Correct number of notifications were sent when configured."
+pass "Correct number of notifications were sent when configured."

 MESSAGE_TITLE=$(curl -sSL http://admin:custom@localhost:8080/message | jq -r '.messages[0].title')
 MESSAGE_BODY=$(curl -sSL http://admin:custom@localhost:8080/message | jq -r '.messages[0].message')

-if [ "$MESSAGE_TITLE" != "Successful test run, yay!" ]; then
-  echo "[TEST:FAIL] Unexpected notification title $MESSAGE_TITLE"
-  exit 1
+if [ "$MESSAGE_TITLE" != "Successful test run with extra-value, yay!" ]; then
+  fail "Unexpected notification title $MESSAGE_TITLE"
 fi
-echo "[TEST:PASS] Custom notification title was used."
+pass "Custom notification title was used."

 if [ "$MESSAGE_BODY" != "Backing up /tmp/test.tar.gz succeeded." ]; then
-  echo "[TEST:FAIL] Unexpected notification body $MESSAGE_BODY"
-  exit 1
+  fail "Unexpected notification body $MESSAGE_BODY"
 fi
-echo "[TEST:PASS] Custom notification body was used."
+pass "Custom notification body was used."

 docker-compose down --volumes
--- a/test/ownership/run.sh
+++ b/test/ownership/run.sh
@@ -4,6 +4,8 @@
 set -e

 cd $(dirname $0)
+. ../util.sh
+current_test=$(basename $(pwd))

 mkdir -p local

@@ -12,17 +14,17 @@ sleep 5

 docker-compose exec backup backup

-sudo tar --same-owner -xvf ./local/backup.tar.gz -C /tmp
+tmp_dir=$(mktemp -d)
+sudo tar --same-owner -xvf ./local/backup.tar.gz -C $tmp_dir

-sudo find /tmp/backup/postgres > /dev/null
-echo "[TEST:PASS] Backup contains files at expected location"
+sudo find $tmp_dir/backup/postgres > /dev/null
+pass "Backup contains files at expected location"

-for file in $(sudo find /tmp/backup/postgres); do
+for file in $(sudo find $tmp_dir/backup/postgres); do
  if [ "$(sudo stat -c '%u:%g' $file)" != "70:70" ]; then
-    echo "[TEST:FAIL] Unexpected file ownership for $file: $(sudo stat -c '%u:%g' $file)"
-    exit 1
+    fail "Unexpected file ownership for $file: $(sudo stat -c '%u:%g' $file)"
  fi
 done
-echo "[TEST:PASS] All files and directories in backup preserved their ownership."
+pass "All files and directories in backup preserved their ownership."

 docker-compose down --volumes
--- a/test/compose/docker-compose.yml
+++ b/test/compose/docker-compose.yml
@@ -12,21 +12,11 @@ services:
    volumes:
      - minio_backup_data:/data

-  webdav:
-    image: bytemark/webdav:2.4
-    environment:
-      AUTH_TYPE: Digest
-      USERNAME: test
-      PASSWORD: test
-    volumes:
-      - webdav_backup_data:/var/lib/dav
-
  backup:
    image: offen/docker-volume-backup:${TEST_VERSION:-canary}
    hostname: hostnametoken
    depends_on:
      - minio
-      - webdav
    restart: always
    environment:
      AWS_ACCESS_KEY_ID: test
@@ -36,18 +26,11 @@ services:
      AWS_S3_BUCKET_NAME: backup
      BACKUP_FILENAME_EXPAND: 'true'
      BACKUP_FILENAME: test-$$HOSTNAME.tar.gz
-      BACKUP_LATEST_SYMLINK: test-$$HOSTNAME.latest.tar.gz.gpg
      BACKUP_CRON_EXPRESSION: 0 0 5 31 2 ?
      BACKUP_RETENTION_DAYS: ${BACKUP_RETENTION_DAYS:-7}
      BACKUP_PRUNING_LEEWAY: 5s
      BACKUP_PRUNING_PREFIX: test
-      GPG_PASSPHRASE: 1234secret
-      WEBDAV_URL: http://webdav/
-      WEBDAV_PATH: /my/new/path/
-      WEBDAV_USERNAME: test
-      WEBDAV_PASSWORD: test
    volumes:
-      - ./local:/archive
      - app_data:/backup/app_data:ro
      - /var/run/docker.sock:/var/run/docker.sock

@@ -60,5 +43,5 @@ services:

 volumes:
  minio_backup_data:
-  webdav_backup_data:
+    name: minio_backup_data
  app_data:
--- a/test/s3/run.sh
+++ b/test/s3/run.sh
@@ -0,0 +1,42 @@
+#!/bin/sh
+
+set -e
+
+cd "$(dirname "$0")"
+. ../util.sh
+current_test=$(basename $(pwd))
+
+docker-compose up -d
+sleep 5
+
+# A symlink for a known file in the volume is created so the test can check
+# whether symlinks are preserved on backup.
+docker-compose exec backup backup
+
+sleep 5
+
+expect_running_containers "3"
+
+docker run --rm -it \
+  -v minio_backup_data:/minio_data \
+  alpine \
+  ash -c 'tar -xvf /minio_data/backup/test-hostnametoken.tar.gz -C /tmp && test -f /tmp/backup/app_data/offen.db'
+
+pass "Found relevant files in untared remote backups."
+
+# The second part of this test checks if backups get deleted when the retention
+# is set to 0 days (which it should not as it would mean all backups get deleted)
+# TODO: find out if we can test actual deletion without having to wait for a day
+BACKUP_RETENTION_DAYS="0" docker-compose up -d
+sleep 5
+
+docker-compose exec backup backup
+
+docker run --rm -it \
+  -v minio_backup_data:/minio_data \
+  alpine \
+  ash -c '[ $(find /minio_data/backup/ -type f | wc -l) = "1" ]'
+
+pass "Remote backups have not been deleted."
+
+docker-compose down --volumes
--- a/test/secret/docker-compose.yml
+++ b/test/secret/docker-compose.yml
@@ -0,0 +1,89 @@
+# Copyright 2020-2021 - Offen Authors <hioffen@posteo.de>
+# SPDX-License-Identifier: Unlicense
+
+version: '3.8'
+
+services:
+  minio_setup:
+    image: alpine:latest
+    deploy:
+      restart_policy:
+        condition: none
+    volumes:
+      - backup_data:/data
+    command: mkdir -p /data/backup
+    
+  minio:
+    image: minio/minio:RELEASE.2021-12-20T22-07-16Z
+    deploy:
+      restart_policy:
+        condition: on-failure
+    environment:
+      MINIO_ROOT_USER_FILE: /run/secrets/minio_root_user
+      MINIO_ROOT_PASSWORD_FILE: /run/secrets/minio_root_password
+    command: minio server /data
+    volumes:
+      - backup_data:/data
+    secrets:
+      - minio_root_user
+      - minio_root_password
+    depends_on:
+      - minio_setup
+
+  backup:
+    image: offen/docker-volume-backup:${TEST_VERSION:-canary}
+    depends_on:
+      - minio
+    deploy:
+      restart_policy:
+        condition: on-failure
+    environment:
+      AWS_ACCESS_KEY_ID_FILE: /run/secrets/minio_root_user
+      AWS_SECRET_ACCESS_KEY_FILE: /run/secrets/minio_root_password
+      AWS_ENDPOINT: minio:9000
+      AWS_ENDPOINT_PROTO: http
+      AWS_S3_BUCKET_NAME: backup
+      BACKUP_FILENAME: test.tar.gz
+      BACKUP_CRON_EXPRESSION: 0 0 5 31 2 ?
+      BACKUP_RETENTION_DAYS: 7
+      BACKUP_PRUNING_LEEWAY: 5s
+    volumes:
+      - pg_data:/backup/pg_data:ro
+      - /var/run/docker.sock:/var/run/docker.sock
+    secrets:
+      - minio_root_user
+      - minio_root_password
+
+  offen:
+    image: offen/offen:latest
+    labels:
+      - docker-volume-backup.stop-during-backup=true
+    healthcheck:
+      disable: true
+    deploy:
+      replicas: 2
+      restart_policy:
+        condition: on-failure
+
+  pg:
+    image: postgres:14-alpine
+    environment:
+      POSTGRES_PASSWORD: example
+    labels:
+      - docker-volume-backup.stop-during-backup=true
+    volumes:
+      - pg_data:/var/lib/postgresql/data
+    deploy:
+      restart_policy:
+        condition: on-failure
+
+volumes:
+  backup_data:
+    name: backup_data
+  pg_data:
+
+secrets:
+  minio_root_user:
+    external: true
+  minio_root_password:
+    external: true
--- a/test/secret/run.sh
+++ b/test/secret/run.sh
@@ -0,0 +1,44 @@
+#!/bin/sh
+
+set -e
+
+cd $(dirname $0)
+. ../util.sh
+current_test=$(basename $(pwd))
+
+docker swarm init
+
+printf "test" | docker secret create minio_root_user -
+printf "GMusLtUmILge2by+z890kQ" | docker secret create minio_root_password -
+
+docker stack deploy --compose-file=docker-compose.yml test_stack
+
+while [ -z $(docker ps -q -f name=backup) ]; do
+  info "Backup container not ready yet. Retrying."
+  sleep 1
+done
+
+sleep 20
+
+docker exec $(docker ps -q -f name=backup) backup
+
+docker run --rm -it \
+  -v backup_data:/data alpine \
+  ash -c 'tar -xf /data/backup/test.tar.gz && test -f /backup/pg_data/PG_VERSION'
+
+pass "Found relevant files in untared backup."
+
+sleep 5
+expect_running_containers "5"
+
+docker stack rm test_stack
+
+docker secret rm minio_root_password
+docker secret rm minio_root_user
+
+docker swarm leave --force
+
+sleep 10
+
+docker volume rm backup_data
+docker volume rm test_stack_pg_data
--- a/test/ssh/docker-compose.yml
+++ b/test/ssh/docker-compose.yml
@@ -0,0 +1,47 @@
+version: '3'
+
+services:
+  ssh:
+    image: linuxserver/openssh-server:version-8.6_p1-r3
+    environment:
+      - PUID=1000
+      - PGID=1000
+      - USER_NAME=test
+    volumes:
+      - ./id_rsa.pub:/config/.ssh/authorized_keys
+      - ssh_backup_data:/tmp
+
+  backup:
+    image: offen/docker-volume-backup:${TEST_VERSION:-canary}
+    hostname: hostnametoken
+    depends_on:
+      - ssh
+    restart: always
+    environment:
+      BACKUP_FILENAME_EXPAND: 'true'
+      BACKUP_FILENAME: test-$$HOSTNAME.tar.gz
+      BACKUP_CRON_EXPRESSION: 0 0 5 31 2 ?
+      BACKUP_RETENTION_DAYS: ${BACKUP_RETENTION_DAYS:-7}
+      BACKUP_PRUNING_LEEWAY: 5s
+      BACKUP_PRUNING_PREFIX: test
+      SSH_HOST_NAME: ssh
+      SSH_PORT: 2222
+      SSH_USER: test
+      SSH_REMOTE_PATH: /tmp
+      SSH_IDENTITY_PASSPHRASE: test1234
+    volumes:
+      - ./id_rsa:/root/.ssh/id_rsa
+      - app_data:/backup/app_data:ro
+      - /var/run/docker.sock:/var/run/docker.sock
+
+  offen:
+    image: offen/offen:latest
+    labels:
+      - docker-volume-backup.stop-during-backup=true
+    volumes:
+      - app_data:/var/opt/offen
+
+volumes:
+  ssh_backup_data:
+    name: ssh_backup_data
+  app_data:
--- a/test/ssh/run.sh
+++ b/test/ssh/run.sh
@@ -0,0 +1,43 @@
+#!/bin/sh
+
+set -e
+
+cd "$(dirname "$0")"
+. ../util.sh
+current_test=$(basename $(pwd))
+
+ssh-keygen -t rsa -m pem -b 4096 -N "test1234" -f id_rsa -C "docker-volume-backup@local"
+
+docker-compose up -d
+sleep 5
+
+docker-compose exec backup backup
+
+sleep 5
+
+expect_running_containers 3
+
+docker run --rm -it \
+  -v ssh_backup_data:/ssh_data \
+  alpine \
+  ash -c 'tar -xvf /ssh_data/test-hostnametoken.tar.gz -C /tmp && test -f /tmp/backup/app_data/offen.db'
+
+pass "Found relevant files in decrypted and untared remote backups."
+
+# The second part of this test checks if backups get deleted when the retention
+# is set to 0 days (which it should not as it would mean all backups get deleted)
+# TODO: find out if we can test actual deletion without having to wait for a day
+BACKUP_RETENTION_DAYS="0" docker-compose up -d
+sleep 5
+
+docker-compose exec backup backup
+
+docker run --rm -it \
+  -v ssh_backup_data:/ssh_data \
+  alpine \
+  ash -c '[ $(find /ssh_data/ -type f | wc -l) = "1" ]'
+
+pass "Remote backups have not been deleted."
+
+docker-compose down --volumes
+rm -f id_rsa id_rsa.pub
--- a/test/swarm/docker-compose.yml
+++ b/test/swarm/docker-compose.yml
@@ -43,6 +43,8 @@ services:
    image: offen/offen:latest
    labels:
      - docker-volume-backup.stop-during-backup=true
+    healthcheck:
+      disable: true
    deploy:
      replicas: 2
      restart_policy:
@@ -62,4 +64,5 @@ services:

 volumes:
  backup_data:
+    name: backup_data
  pg_data:
--- a/test/swarm/run.sh
+++ b/test/swarm/run.sh
@@ -3,13 +3,15 @@
 set -e

 cd $(dirname $0)
+. ../util.sh
+current_test=$(basename $(pwd))

 docker swarm init

 docker stack deploy --compose-file=docker-compose.yml test_stack

 while [ -z $(docker ps -q -f name=backup) ]; do
-  echo "[TEST:INFO] Backup container not ready yet. Retrying."
+  info "Backup container not ready yet. Retrying."
  sleep 1
 done

@@ -18,18 +20,18 @@ sleep 20
 docker exec $(docker ps -q -f name=backup) backup

 docker run --rm -it \
-  -v test_stack_backup_data:/data alpine \
+  -v backup_data:/data alpine \
  ash -c 'tar -xf /data/backup/test.tar.gz && test -f /backup/pg_data/PG_VERSION'

-echo "[TEST:PASS] Found relevant files in untared backup."
+pass "Found relevant files in untared backup."

 sleep 5
-if [ "$(docker ps -q | wc -l)" != "5" ]; then
-  echo "[TEST:FAIL] Expected all containers to be running post backup, instead seen:"
-  docker ps -a
-  exit 1
-fi
-echo "[TEST:PASS] All containers running post backup."
+expect_running_containers "5"

 docker stack rm test_stack
 docker swarm leave --force
+
+sleep 10
+
+docker volume rm backup_data
+docker volume rm test_stack_pg_data
--- a/test/util.sh
+++ b/test/util.sh
@@ -0,0 +1,23 @@
+#!/bin/sh
+
+set -e
+
+info () {
+  echo "[test:${current_test:-none}:info] "$1""
+}
+
+pass () {
+  echo "[test:${current_test:-none}:pass] "$1""
+}
+
+fail () {
+  echo "[test:${current_test:-none}:fail] "$1""
+  exit 1
+}
+
+expect_running_containers () {
+  if [ "$(docker ps -q | wc -l)" != "$1" ]; then
+    fail "Expected $1 containers to be running, instead seen: "$(docker ps -a | wc -l)""
+  fi
+  pass "$1 containers running."
+}
--- a/test/webdav/docker-compose.yml
+++ b/test/webdav/docker-compose.yml
@@ -0,0 +1,45 @@
+version: '3'
+
+services:
+  webdav:
+    image: bytemark/webdav:2.4
+    environment:
+      AUTH_TYPE: Digest
+      USERNAME: test
+      PASSWORD: test
+    volumes:
+      - webdav_backup_data:/var/lib/dav
+
+  backup:
+    image: offen/docker-volume-backup:${TEST_VERSION:-canary}
+    hostname: hostnametoken
+    depends_on:
+      - webdav
+    restart: always
+    environment:
+      BACKUP_FILENAME_EXPAND: 'true'
+      BACKUP_FILENAME: test-$$HOSTNAME.tar.gz
+      BACKUP_CRON_EXPRESSION: 0 0 5 31 2 ?
+      BACKUP_RETENTION_DAYS: ${BACKUP_RETENTION_DAYS:-7}
+      BACKUP_PRUNING_LEEWAY: 5s
+      BACKUP_PRUNING_PREFIX: test
+      WEBDAV_URL: http://webdav/
+      WEBDAV_URL_INSECURE: 'true'
+      WEBDAV_PATH: /my/new/path/
+      WEBDAV_USERNAME: test
+      WEBDAV_PASSWORD: test
+    volumes:
+      - app_data:/backup/app_data:ro
+      - /var/run/docker.sock:/var/run/docker.sock
+
+  offen:
+    image: offen/offen:latest
+    labels:
+      - docker-volume-backup.stop-during-backup=true
+    volumes:
+      - app_data:/var/opt/offen
+
+volumes:
+  webdav_backup_data:
+    name: webdav_backup_data
+  app_data:
--- a/test/webdav/run.sh
+++ b/test/webdav/run.sh
@@ -0,0 +1,40 @@
+#!/bin/sh
+
+set -e
+
+cd "$(dirname "$0")"
+. ../util.sh
+current_test=$(basename $(pwd))
+
+docker-compose up -d
+sleep 5
+
+docker-compose exec backup backup
+
+sleep 5
+
+expect_running_containers "3"
+
+docker run --rm -it \
+  -v webdav_backup_data:/webdav_data \
+  alpine \
+  ash -c 'tar -xvf /webdav_data/data/my/new/path/test-hostnametoken.tar.gz -C /tmp && test -f /tmp/backup/app_data/offen.db'
+
+pass "Found relevant files in untared remote backup."
+
+# The second part of this test checks if backups get deleted when the retention
+# is set to 0 days (which it should not as it would mean all backups get deleted)
+# TODO: find out if we can test actual deletion without having to wait for a day
+BACKUP_RETENTION_DAYS="0" docker-compose up -d
+sleep 5
+
+docker-compose exec backup backup
+
+docker run --rm -it \
+  -v webdav_backup_data:/webdav_data \
+  alpine \
+  ash -c '[ $(find /webdav_data/data/my/new/path/ -type f | wc -l) = "1" ]'
+
+pass "Remote backups have not been deleted."
+
+docker-compose down --volumes
Author	SHA1	Message	Date
Frederik Ring	dec7d7e2c0	Lock version of Docker Credential Helper in CI	2022-10-12 20:23:40 +02:00
pixxon	b5cc1262e2	add aws secret handling (#161 ) * add aws secret handling * make it look go-ish * fix tests * whitespace * sleep a bit	2022-10-12 19:14:57 +02:00
Frederik Ring	00c83dfac7	Fix more error strings	2022-09-15 10:49:45 +02:00
Frederik Ring	eb9a198327	Ensure consistency in error messages	2022-09-15 10:04:12 +02:00
Frederik Ring	97e975a535	Add FUNDING.yml	2022-09-02 09:39:55 +02:00
Frederik Ring	749a7a15a6	Build using Go 1.19 (#153 )	2022-09-01 15:12:48 +02:00
Frederik Ring	a6ec128cab	Run copying and pruning against multiple storages in parallel (#152 )	2022-09-01 14:38:04 +02:00
Frederik Ring	695a94d479	Add template for support request issue	2022-09-01 14:30:42 +02:00
Frederik Ring	2316111892	Fix key location in container in SSH example	2022-08-29 17:10:07 +02:00
Frederik Ring	b60c747448	Fix WebDAV spelling, remove some inconsistencies (#143 ) * Simplify logging, fix WebDAV spelling * Define options types per package * Move util functions that are not used cross package * Add per file license headers * Rename config type	2022-08-18 12:37:45 +02:00
MaxJa4	279844ccfb	Added abstract helper interface for all storage backends (#135 ) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo	2022-08-18 12:37:45 +02:00
Frederik Ring	4ec88d14dd	Update issue templates (#145 )	2022-08-18 10:59:34 +02:00
Frederik Ring	599b7f3f74	Use crontab command to recreate empty tab file (#141 )	2022-08-15 15:00:58 +02:00
Frederik Ring	b2d4c48082	Update base image to alpine:3.16 (#124 )	2022-08-15 09:25:47 +02:00
MaxJa4	2b7f0c52c0	Print more error info for minio (#136 ) * Print more error info for minio * Unpacked error info	2022-08-15 09:25:32 +02:00
Frederik Ring	cc912d7b64	Delete existing crontab before appending entries per conf.d (#140 )	2022-08-15 09:25:19 +02:00
Frederik Ring	26c8ba971f	Add test case for exec label (#132 )	2022-07-15 09:34:01 +02:00
Alexander Zimmermann	3f10d0f817	Update README.md (#130 ) Replace deprecated exec-pre label	2022-07-14 13:47:54 +02:00
Frederik Ring	b441cf3e2b	Fine grained labels (#115 ) * Refactor label command mechanism to be more flexible * Run all steps wrapped in labeled commands * Rename methods to be in line with lifecycle * Deprecate exec-pre and exec-post labels * Add documentation * Use type alias for lifecycle phases * Fix bad imports * Fix command lookup for deprecated labels * Use more generic naming for lifecycle phase * Fail on erroneous post command * Update documentation	2022-07-10 10:36:56 +02:00
Frederik Ring	82f66565da	Add further docs on backup selection when using conf.d	2022-07-08 14:05:45 +02:00
Frederik Ring	d68814be9d	Add section about shoutrrr CLI tool to README	2022-07-07 22:22:21 +02:00
Erwan LE PRADO	3661a4b49b	feat: Add storage class header (#119 ) * feat: Add storage class header * doc: change the readme * chore: Remove the unnecessary default value	2022-07-06 13:18:12 +02:00
Frederik Ring	e738bd0539	Make crond log to stderr so Docker can forward it (#120 )	2022-07-06 13:16:43 +02:00
Frederik Ring	342ae5910e	Add env template helper (#121 )	2022-07-06 13:16:32 +02:00
Frederik Ring	c2a8cc92fc	Untangle tests (#112 ) * Isolate S3 test case * Isolate webdav test case * Isolate SSH test case * Isolate local storage test case * Isolate gpg test case * Add missing volume mount * Fix file locations for local test case * Remove compose test case, use utils * Use test utils throughout * Use dedicated tmp dir * Fix link location that is being tested * Use dedicated tmp_dirs when working on host fs * Force delete artifact * Fix expected filename * Provide helpful messages on failing tests * Fix filename * Use proper volume names * Fix syntax error, use large resource class * Use named Docker volumes when referencing them in test scripts * Add name of test case to logging output	2022-06-23 14:40:29 +02:00
Frederik Ring	1892d56ff6	Change default value for SSH identity file (#108 ) * Change default value for SSH identity file * Force remove write protected file in tests	2022-06-17 11:28:29 +02:00
İbrahim Akyel	0b205fe6dc	SSH Backup Storage Support (#107 ) * SSH Client implemented * Private key auth implemented Code refactoring * Refactoring * Passphrase renamed to IdentityPassphrase Default private key location changed to .ssh/id	2022-06-17 11:06:15 +02:00
Frederik Ring	8c8a2fa088	Update vulnerable containerd dependency (#104 )	2022-06-07 09:21:40 +02:00
Frederik Ring	a850bf13fe	Fix broken link in README	2022-05-12 08:18:12 +02:00
Frederik Ring	b52b271bac	Allow for the exclusion of files from backups (#100 ) * Hoist walking of files so it can be used for features other than archive creation * Add option to ignore files from backup using glob patterns * Use Regexp instead of glob for exclusion * Ignore artifacts * Add teardown to test * Allow single Re for filtering only * Add documentation * Use MatchString on re, add bad input to message in case of error	2022-05-08 11:20:38 +02:00
Frederik Ring	cac5777e79	Add documentation on using multiple configs for complex retention schemes	2022-04-20 18:01:41 +02:00
Frederik Ring	94a1edc4ad	Allow disabling of certificate verification for WebDAV (#98 )	2022-04-20 14:16:59 +02:00
Frederik Ring	a654097e59	Update webdav client library (#97 )	2022-04-20 10:56:26 +02:00
Frederik Ring	1b1fc4856c	List objects recursively when selecting candidates from S3 (#92 )	2022-04-15 11:05:52 +02:00
Frederik Ring	e81c34b8fc	Consider S3 Path when selecting candidates for pruning (#91 )	2022-04-13 17:09:37 +02:00
Simon Dünhöft	9c23767fce	Fixed wrong env name for S3 bucket in README (#89 ) The README was using `AWS_BUCKET_NAME` instead of `AWS_S3_BUCKET_NAME` in the recipes. This resulted in no data being uploaded to S3.	2022-04-12 19:38:15 +02:00
Frederik Ring	51af8c3c77	Deprecate BACKUP_FROM_SNAPSHOT (#81 )	2022-03-25 18:28:58 +01:00
Frederik Ring	1ea0b51b23	Tag releases with major version too (#82 )	2022-03-25 18:27:00 +01:00
Frederik Ring	da8c63f755	Support identical cron schedule (#87 ) * Retry on lock being unavailable * Refactor locking to return plain error * Collect LockedTime in stats * Add test case * Add documentation for LOCK_TIMEOUT * Log in case lock needs to be awaited * Release resources created for awaiting lock	2022-03-25 18:26:34 +01:00
Frederik Ring	9bc8db0f7c	Build using Go 1.18 (#86 )	2022-03-17 11:22:41 +01:00
Frederik Ring	508bc07b4f	Disable healthcheck in swarm test (#85 )	2022-03-17 11:13:07 +01:00
Frederik Ring	b8f71b04a1	Use errgroup for running commands in parallel (#83 )	2022-03-10 11:09:39 +01:00
Frederik Ring	5f3832d621	Consider prefix rules when pruning WebDAV storages (#79 )	2022-03-05 13:33:15 +01:00
Frederik Ring	4b1127b8c4	Document BACKUP_SOURCES	2022-03-04 19:57:32 +01:00
Frederik Ring	ae50a3ac4f	Add attribution to code taken from moby repository	2022-03-04 16:40:34 +01:00
Frederik Ring	bad22eee93	Fix syntax highlighting in container	2022-03-04 14:08:31 +01:00