Support _FILE based configuration values (#264)

* Replace envconfig with env

* Adjust config options and processing

* Added _FILE variant for all password vars.

* Try pathenvconfig

* Revert everything so far

* Use our fork of envconfig with custom lookup

* Use our fork of envconfig with custom lookup

* Test compose timeout option

* Remove secret resolving and specific _FILE config

* Fix timing issue in swarm tests

* Revert "Test compose timeout option"

This reverts commit ab50b21748, reversing
changes made to 0282514b2b.

Revert "Test compose timeout option"

This reverts commit 0282514b2b.

* Use offen/envconfig v1.5.0

* Add info about _FILE in README

* Value > File. Panic on file error. Panic on duplicate presence.

* Test panic on duplicate vars and panic on file error.

.circleci/config.yml

@@ -1,75 +0,0 @@
-version: 2.1
-
-jobs:
-  canary:
-    machine:
-      image: ubuntu-2004:202201-02
-    working_directory: ~/docker-volume-backup
-    resource_class: large
-    steps:
-      - checkout
-      - run:
-          name: Build
-          command: |
-            docker build . -t offen/docker-volume-backup:canary
-      - run:
-          name: Install gnupg
-          command: |
-            sudo apt-get install -y gnupg
-      - run:
-          name: Run tests
-          working_directory: ~/docker-volume-backup/test
-          command: |
-            export GPG_TTY=$(tty)
-            ./test.sh canary
-
-  build:
-    docker:
-      - image: cimg/base:2020.06
-        environment:
-          DOCKER_BUILDKIT: '1'
-          DOCKER_CLI_EXPERIMENTAL: enabled
-    working_directory: ~/docker-volume-backup
-    resource_class: large
-    steps:
-      - checkout
-      - setup_remote_docker:
-          version: 20.10.6
-      - docker/install-docker-credential-helper:
-          release-tag: v0.6.4
-      - docker/configure-docker-credentials-store
-      - run:
-          name: Push to Docker Hub
-          command: |
-            echo "$DOCKER_ACCESSTOKEN" | docker login --username offen --password-stdin
-            # This is required for building ARM: https://gitlab.alpinelinux.org/alpine/aports/-/issues/12406
-            docker run --rm --privileged linuxkit/binfmt:v0.8
-            docker context create docker-volume-backup
-            docker buildx create docker-volume-backup --name docker-volume-backup --use
-            docker buildx inspect --bootstrap
-            tag_args="-t offen/docker-volume-backup:$CIRCLE_TAG"
-            if [[ "$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
-
-workflows:
-  version: 2
-  docker_image:
-    jobs:
-      - canary:
-          filters:
-            tags:
-              ignore: /^v.*/
-      - build:
-          filters:
-            branches:
-              ignore: /.*/
-            tags:
-              only: /^v.*/
-
-orbs:
-  docker: circleci/docker@2.1.4

.github/dependabot.yml

@@ -0,0 +1,10 @@
+version: 2
+updates:
+  - package-ecosystem: docker
+    directory: /
+    schedule:
+      interval: weekly
+  - package-ecosystem: gomod
+    directory: /
+    schedule:
+      interval: weekly

.github/workflows/golangci-lint.yml

@@ -0,0 +1,54 @@
+name: Run Linters
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+permissions:
+  contents: read
+  # Optional: allow read access to pull request. Use with `only-new-issues` option.
+  pull-requests: read
+
+jobs:
+  golangci:
+    name: lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-go@v4
+        with:
+          go-version: '1.21'
+          cache: false
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v3
+        with:
+          # Require: The version of golangci-lint to use.
+          # When `install-mode` is `binary` (default) the value can be v1.2 or v1.2.3 or `latest` to use the latest version.
+          # When `install-mode` is `goinstall` the value can be v1.2.3, `latest`, or the hash of a commit.
+          version: v1.54
+
+          # Optional: working directory, useful for monorepos
+          # working-directory: somedir
+
+          # Optional: golangci-lint command line arguments.
+          #
+          # Note: By default, the `.golangci.yml` file should be at the root of the repository.
+          # The location of the configuration file can be changed by using `--config=`
+          # args: --timeout=30m --config=/my/path/.golangci.yml --issues-exit-code=0
+
+          # Optional: show only new issues if it's a pull request. The default value is `false`.
+          # only-new-issues: true
+
+          # Optional: if set to true, then all caching functionality will be completely disabled,
+          #           takes precedence over all other caching options.
+          # skip-cache: true
+
+          # Optional: if set to true, then the action won't cache or restore ~/go/pkg.
+          # skip-pkg-cache: true
+
+          # Optional: if set to true, then the action won't cache or restore ~/.cache/go-build.
+          # skip-build-cache: true
+
+          # Optional: The mode to install golangci-lint. It can be 'binary' or 'goinstall'.
+          # install-mode: "goinstall"

.github/workflows/release.yml

@@ -0,0 +1,59 @@
+name: Release Docker Image
+
+on:
+  push:
+    tags: v**
+
+jobs:
+  push_to_registries:
+    name: Push Docker image to multiple registries
+    runs-on: ubuntu-latest
+    permissions:
+      packages: write
+      contents: read
+    steps:
+      - name: Check out the repo
+        uses: actions/checkout@v3
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+
+      - name: Log in to Docker Hub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKER_USERNAME }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+
+      - name: Log in to GHCR
+        uses: docker/login-action@v2
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract Docker tags
+        id: meta
+        run: |
+          version_tag="${{github.ref_name}}"
+          tags=($version_tag)
+          if [[ "$version_tag" =~ ^v[0-9]+\.[0-9]+\.[0-9]+$ ]]; then
+            # prerelease tags like `v2.0.0-alpha.1` should not be released as `latest` nor `v2`
+            tags+=("latest")
+            tags+=($(echo "$version_tag" | cut -d. -f1))
+          fi
+          releases=""
+          for tag in "${tags[@]}"; do
+            releases="${releases:+$releases,}offen/docker-volume-backup:$tag,ghcr.io/offen/docker-volume-backup:$tag"
+          done
+          echo "releases=$releases" >> "$GITHUB_OUTPUT"
+
+      - name: Build and push Docker images
+        uses: docker/build-push-action@v4
+        with:
+          context: .
+          push: true
+          platforms: linux/amd64,linux/arm64,linux/arm/v7
+          tags: ${{ steps.meta.outputs.releases }}

.github/workflows/test.yml

@@ -0,0 +1,30 @@
+name: Run Integration Tests
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+
+      - name: Build Docker Image
+        env:
+          DOCKER_BUILDKIT: '1'
+        run: docker build . -t offen/docker-volume-backup:test
+
+      - name: Run Tests
+        working-directory: ./test
+        run: |
+          # Stop the buildx container so the tests can make assertions
+          # about the number of running containers
+          docker rm -f $(docker ps -aq)
+          export GPG_TTY=$(tty)
+          ./test.sh test

.golangci.yml

@@ -0,0 +1,8 @@
+linters:
+  # Enable specific linter
+  # https://golangci-lint.run/usage/linters/#enabled-by-default
+  enable:
+    - staticcheck
+    - govet
+output:
+  format: github-actions

Dockerfile

@@ -1,7 +1,7 @@
 # Copyright 2021 - Offen Authors <hioffen@posteo.de>
 # SPDX-License-Identifier: MPL-2.0
 
-FROM golang:1.19-alpine as builder
+FROM golang:1.21-alpine as builder
 
 WORKDIR /app
 COPY . .
@@ -9,15 +9,13 @@ RUN go mod download
 WORKDIR /app/cmd/backup
 RUN go build -o backup .
 
-FROM alpine:3.17
+FROM alpine:3.18
 
 WORKDIR /root
 
 RUN apk add --no-cache ca-certificates
 
 COPY --from=builder /app/cmd/backup/backup /usr/bin/backup
-
-COPY ./entrypoint.sh /root/
-RUN chmod +x entrypoint.sh
+COPY --chmod=755 ./entrypoint.sh /root/
 
 ENTRYPOINT ["/root/entrypoint.sh"]

README.md

@@ -4,16 +4,17 @@
 
 # docker-volume-backup
 
-Backup Docker volumes locally or to any S3, WebDAV, Azure Blob Storage or SSH compatible storage.
+Backup Docker volumes locally or to any S3, WebDAV, Azure Blob Storage, Dropbox or SSH 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, WebDAV, Azure Blob Storage 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__.
+It handles __recurring or one-off backups of Docker volumes__ to a __local directory__, __any S3, WebDAV, Azure Blob Storage, Dropbox 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 -->
 
 - [Quickstart](#quickstart)
   - [Recurring backups in a compose setup](#recurring-backups-in-a-compose-setup)
   - [One-off backups using Docker CLI](#one-off-backups-using-docker-cli)
+  - [Available image registries](#available-image-registries)
 - [Configuration reference](#configuration-reference)
 - [How to](#how-to)
   - [Stop containers during backup](#stop-containers-during-backup)
@@ -30,10 +31,12 @@ It handles __recurring or one-off backups of Docker volumes__ to a __local direc
   - [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)
+  - [Use with rootless Docker](#use-with-rootless-docker)
   - [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)
   - [Handle file uploads using third party tools](#handle-file-uploads-using-third-party-tools)
+  - [Setup Dropbox storage backend](#setup-dropbox-storage-backend)
 - [Recipes](#recipes)
   - [Backing up to AWS S3](#backing-up-to-aws-s3)
   - [Backing up to Filebase](#backing-up-to-filebase)
@@ -42,6 +45,7 @@ It handles __recurring or one-off backups of Docker volumes__ to a __local direc
   - [Backing up to WebDAV](#backing-up-to-webdav)
   - [Backing up to SSH](#backing-up-to-ssh)
   - [Backing up to Azure Blob Storage](#backing-up-to-azure-blob-storage)
+  - [Backing up to Dropbox](#backing-up-to-dropbox)
   - [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)
@@ -120,9 +124,24 @@ docker run --rm \
 
 Alternatively, pass a `--env-file` in order to use a full config as described below.
 
+### Available image registries
+
+This Docker image is published to both Docker Hub and the GitHub container registry.
+Depending on your preferences and needs, you can reference both `offen/docker-volume-backup` as well as `ghcr.io/offen/docker-volume-backup`:
+
+```
+docker pull offen/docker-volume-backup:v2
+docker pull ghcr.io/offen/docker-volume-backup:v2
+```
+
+Documentation references Docker Hub, but all examples will work using ghcr.io just as well.
+
 ## Configuration reference
 
 Backup targets, schedule and retention are configured in environment variables.
+
+Note: You can use any environment variable from below also with a `_FILE` suffix to be able to load the value from a file. This is usually useful when using [Docker Secrets](https://docs.docker.com/engine/swarm/secrets/) or similar.
+
 You can populate below template according to your requirements and use it as your `env_file`:
 
 ```ini
@@ -134,13 +153,22 @@ You can populate below template according to your requirements and use it as you
 
 # BACKUP_CRON_EXPRESSION="0 2 * * *"
 
-# The name of the backup file including the `.tar.gz` extension.
+# The compression algorithm used in conjunction with tar.
+# Valid options are: "gz" (Gzip) and "zst" (Zstd).
+# Note that the selection affects the file extension.
+
+# BACKUP_COMPRESSION="gz"
+
+# The name of the backup file including the extension.
 # Format verbs will be replaced as in `strftime`. Omitting them
 # will result in the same filename for every backup run, which means previous
-# versions will be overwritten on subsequent runs. The default results
-# in filenames like `backup-2021-08-29T04-00-00.tar.gz`.
+# versions will be overwritten on subsequent runs.
+# Extension can be defined literally or via "{{ .Extension }}" template,
+# in which case it will become either "tar.gz" or "tar.zst" (depending
+# on your BACKUP_COMPRESSION setting).
+# The default results in filenames like: `backup-2021-08-29T04-00-00.tar.gz`.
 
-# BACKUP_FILENAME="backup-%Y-%m-%dT%H-%M-%S.tar.gz"
+# BACKUP_FILENAME="backup-%Y-%m-%dT%H-%M-%S.{{ .Extension }}"
 
 # Setting BACKUP_FILENAME_EXPAND to true allows for environment variable
 # placeholders in BACKUP_FILENAME, BACKUP_LATEST_SYMLINK and in
@@ -180,6 +208,15 @@ You can populate below template according to your requirements and use it as you
 
 # BACKUP_EXCLUDE_REGEXP="\.log$"
 
+# Exclude one or many storage backends from the pruning process.
+# E.g. with one backend excluded: BACKUP_SKIP_BACKENDS_FROM_PRUNE=s3
+# E.g. with multiple backends excluded: BACKUP_SKIP_BACKENDS_FROM_PRUNE=s3,webdav
+# Available backends are: S3, WebDAV, SSH, Local, Dropbox, Azure
+# Note: The name of the backends is case insensitive. 
+# Default: All backends get pruned.
+
+# BACKUP_SKIP_BACKENDS_FROM_PRUNE=
+
 ########### BACKUP STORAGE
 
 # The name of the remote bucket that should be used for storing backups. If
@@ -199,14 +236,6 @@ 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
@@ -246,6 +275,15 @@ You can populate below template according to your requirements and use it as you
 
 # AWS_STORAGE_CLASS="GLACIER"
 
+# Setting this variable will change the S3 default part size for the copy step.
+# This value is useful when you want to upload large files.
+# NB : While using Scaleway as S3 provider, be aware that the parts counter is set to 1.000.
+# While Minio uses a hard coded value to 10.000. As a workaround, try to set a higher value.
+# Defaults to "16" (MB) if unset (from minio), you can set this value according to your needs.
+# The unit is in MB and an integer.
+
+# AWS_PART_SIZE=16
+
 # You can also backup files to any WebDAV server:
 
 # The URL of the remote WebDAV server
@@ -324,6 +362,26 @@ You can populate below template according to your requirements and use it as you
 
 # AZURE_STORAGE_ENDPOINT="https://{{ .AccountName }}.blob.core.windows.net/"
 
+# Absolute remote path in your Dropbox where the backups shall be stored.
+# Note: Use your app's subpath in Dropbox, if it doesn't have global access.
+# Consulte the README for further information.
+
+# DROPBOX_REMOTE_PATH="/my/directory"
+
+# Number of concurrent chunked uploads for Dropbox.
+# Values above 6 usually result in no enhancements.
+
+# DROPBOX_CONCURRENCY_LEVEL="6"
+
+# App key and app secret from your app created at https://www.dropbox.com/developers/apps/info
+
+# DROPBOX_APP_KEY=""
+# DROPBOX_APP_SECRET=""
+
+# Refresh token to request new short-lived tokens (OAuth2). Consult README to see how to get one.
+
+# DROPBOX_REFRESH_TOKEN=""
+
 # 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`
@@ -410,7 +468,7 @@ You can populate below template according to your requirements and use it as you
 
 # Notifications (email, Slack, etc.) can be sent out when a backup run finishes.
 # Configuration is provided as a comma-separated list of URLs as consumed
-# by `shoutrrr`: https://containrrr.dev/shoutrrr/v0.5/services/overview/
+# by `shoutrrr`: https://containrrr.dev/shoutrrr/0.7/services/overview/
 # The content of such notifications can be customized. Dedicated documentation
 # on how to do this can be found in the README. When providing multiple URLs or
 # an URL that contains a comma, the values can be URL encoded to avoid ambiguities.
@@ -554,7 +612,7 @@ services:
 Notification backends other than email are also supported.
 Refer to the documentation of [shoutrrr][shoutrrr-docs] to find out about options and configuration.
 
-[shoutrrr-docs]: https://containrrr.dev/shoutrrr/v0.5/services/overview/
+[shoutrrr-docs]: https://containrrr.dev/shoutrrr/0.7/services/overview/
 
 ### Customize notifications
 
@@ -643,6 +701,24 @@ volumes:
 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.
 
+By default the backup command is executed by the user provided by the container's image.
+It is possible to specify a custom user that is used to run commands in dedicated labels with the format `docker-volume-backup.[step]-[pre|post].user`:
+
+```yml
+version: '3'
+
+services:
+  gitea:
+    image: gitea/gitea
+    volumes:
+      - backup_data:/tmp
+    labels:
+      - docker-volume-backup.archive-pre.user=git
+      - docker-volume-backup.archive-pre=/bin/bash -c 'cd /tmp; /usr/local/bin/gitea dump -c /data/gitea/conf/app.ini -R -f dump.zip'
+```
+
+Make sure the user exists and is present in `passwd` inside the target container.
+
 ### Encrypting your backup using GPG
 
 The image supports encrypting backups using GPG out of the box.
@@ -782,7 +858,7 @@ services:
       - docker-volume-backup.archive-post=rm -rf /tmp/backup/my-app
 
   backup:
-    image: offen/docker-volume-backup:latest
+    image: offen/docker-volume-backup:v2
     environment:
       BACKUP_SOURCES: /tmp/backup
     volumes:
@@ -820,6 +896,23 @@ DOCKER_HOST=tcp://docker_socket_proxy:2375
 
 In case you are using a socket proxy, it must support `GET` and `POST` requests to the `/containers` endpoint. If you are using Docker Swarm, it must also support the `/services` endpoint. If you are using pre/post backup commands, it must also support the `/exec` endpoint.
 
+### Use with rootless Docker
+
+It's also possible to use this image with a [rootless Docker installation][rootless-docker].
+Instead of mounting `/var/run/docker.sock`, mount the user-specific socket into the container:
+
+```yml
+services:
+  backup:
+    image: offen/docker-volume-backup:v2
+    # ... configuration omitted
+    volumes:
+      - backup:/backup:ro
+      - /run/user/1000/docker.sock:/var/run/docker.sock:ro
+```
+
+[rootless-docker]: https://docs.docker.com/engine/security/rootless/
+
 ### Run multiple backup schedules in the same container
 
 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`:
@@ -870,7 +963,7 @@ BACKUP_SOURCES=/backup/app2_data
 
 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`:
+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/conf.d`:
 
 ```ini
 # 01daily.conf
@@ -953,6 +1046,37 @@ volumes:
 
 Commands will be invoked with the filepath of the tar archive passed as `COMMAND_RUNTIME_BACKUP_FILEPATH`.
 
+### Setup Dropbox storage backend
+
+#### Auth-Setup:
+
+1. Create a new Dropbox App in the [App Console](https://www.dropbox.com/developers/apps)
+2. Open your new Dropbox App and set `DROPBOX_APP_KEY` and `DROPBOX_APP_SECRET` in your environment (e.g. docker-compose.yml) accordingly
+3. Click on `Permissions` in your app and make sure, that the following permissions are cranted (or more):
+  - `files.metadata.write`
+  - `files.metadata.read`
+  - `files.content.write`
+  - `files.content.read`
+4. Replace APPKEY in `https://www.dropbox.com/oauth2/authorize?client_id=APPKEY&token_access_type=offline&response_type=code` with the app key from step 2
+5. Visit the URL and confirm the access of your app. This gives you an `auth code` -> save it somewhere!
+6. Replace AUTHCODE, APPKEY, APPSECRET accordingly and perform the request:
+```
+curl https://api.dropbox.com/oauth2/token \
+    -d code=AUTHCODE \
+    -d grant_type=authorization_code \
+    -d client_id=APPKEY \
+    -d client_secret=APPSECRET
+```
+7. Execute the request. You will get a JSON formatted reply. Use the value of the `refresh_token` for the last environment variable `DROPBOX_REFRESH_TOKEN`
+8. You should now have `DROPBOX_APP_KEY`, `DROPBOX_APP_SECRET` and `DROPBOX_REFRESH_TOKEN` set. These don't expire.
+
+Note: Using the "Generated access token" in the app console is not supported, as it is only very short lived and therefore not suitable for an automatic backup solution. The refresh token handles this automatically - the setup procedure above is only needed once.
+
+#### Other parameters
+
+Important: If you chose `App folder` access during the creation of your Dropbox app in step 1 above, you can only write in the app's directory!
+This means, that `DROPBOX_REMOTE_PATH` must start with e.g. `/Apps/YOUR_APP_NAME` or `/Apps/YOUR_APP_NAME/some_sub_dir`
+
 ## Recipes
 
 This section lists configuration for some real-world use cases that you can mix and match according to your needs.
@@ -1120,6 +1244,30 @@ volumes:
   data:
 ```
 
+### Backing up to Dropbox
+
+See [Dropbox Setup](#setup-dropbox-storage-backend) on how to get the appropriate environment values.
+
+```yml
+version: '3'
+
+services:
+  # ... define other services using the `data` volume here
+  backup:
+    image: offen/docker-volume-backup:v2
+    environment:
+      DROPBOX_REFRESH_TOKEN: REFRESH_KEY  # replace
+      DROPBOX_APP_KEY: APP_KEY  # replace
+      DROPBOX_APP_SECRET: APP_SECRET  # replace
+      DROPBOX_REMOTE_PATH: /Apps/my-test-app/some_subdir  # replace
+    volumes:
+      - data:/backup/my-app-backup:ro
+      - /var/run/docker.sock:/var/run/docker.sock:ro
+
+volumes:
+  data:
+```
+
 ### Backing up locally
 
 ```yml

cmd/backup/archive.go

@@ -15,9 +15,11 @@ import (
 	"path"
 	"path/filepath"
 	"strings"
+
+	"github.com/klauspost/compress/zstd"
 )
 
-func createArchive(files []string, inputFilePath, outputFilePath string) error {
+func createArchive(files []string, inputFilePath, outputFilePath string, compression string) error {
 	inputFilePath = stripTrailingSlashes(inputFilePath)
 	inputFilePath, outputFilePath, err := makeAbsolute(inputFilePath, outputFilePath)
 	if err != nil {
@@ -27,7 +29,7 @@ func createArchive(files []string, inputFilePath, outputFilePath string) error {
 		return fmt.Errorf("createArchive: error creating output file path: %w", err)
 	}
 
-	if err := compress(files, outputFilePath, filepath.Dir(inputFilePath)); err != nil {
+	if err := compress(files, outputFilePath, filepath.Dir(inputFilePath), compression); err != nil {
 		return fmt.Errorf("createArchive: error creating archive: %w", err)
 	}
 
@@ -51,18 +53,30 @@ func makeAbsolute(inputFilePath, outputFilePath string) (string, string, error)
 	return inputFilePath, outputFilePath, err
 }
 
-func compress(paths []string, outFilePath, subPath string) error {
+func compress(paths []string, outFilePath, subPath string, algo string) error {
 	file, err := os.Create(outFilePath)
+	var compressWriter io.WriteCloser
 	if err != nil {
 		return fmt.Errorf("compress: error creating out file: %w", err)
 	}
 
 	prefix := path.Dir(outFilePath)
-	gzipWriter := gzip.NewWriter(file)
-	tarWriter := tar.NewWriter(gzipWriter)
+	switch algo {
+	case "gz":
+		compressWriter = gzip.NewWriter(file)
+	case "zst":
+		compressWriter, err = zstd.NewWriter(file)
+		if err != nil {
+			return fmt.Errorf("compress: zstd error: %w", err)
+		}
+	default:
+		return fmt.Errorf("compress: unsupported compression algorithm: %s", algo)
+	}
+
+	tarWriter := tar.NewWriter(compressWriter)
 
 	for _, p := range paths {
-		if err := writeTarGz(p, tarWriter, prefix); err != nil {
+		if err := writeTarball(p, tarWriter, prefix); err != nil {
 			return fmt.Errorf("compress: error writing %s to archive: %w", p, err)
 		}
 	}
@@ -72,9 +86,9 @@ func compress(paths []string, outFilePath, subPath string) error {
 		return fmt.Errorf("compress: error closing tar writer: %w", err)
 	}
 
-	err = gzipWriter.Close()
+	err = compressWriter.Close()
 	if err != nil {
-		return fmt.Errorf("compress: error closing gzip writer: %w", err)
+		return fmt.Errorf("compress: error closing compression writer: %w", err)
 	}
 
 	err = file.Close()
@@ -85,10 +99,10 @@ func compress(paths []string, outFilePath, subPath string) error {
 	return nil
 }
 
-func writeTarGz(path string, tarWriter *tar.Writer, prefix string) error {
+func writeTarball(path string, tarWriter *tar.Writer, prefix string) error {
 	fileInfo, err := os.Lstat(path)
 	if err != nil {
-		return fmt.Errorf("writeTarGz: error getting file infor for %s: %w", path, err)
+		return fmt.Errorf("writeTarball: error getting file infor for %s: %w", path, err)
 	}
 
 	if fileInfo.Mode()&os.ModeSocket == os.ModeSocket {
@@ -99,19 +113,19 @@ func writeTarGz(path string, tarWriter *tar.Writer, prefix string) error {
 	if fileInfo.Mode()&os.ModeSymlink == os.ModeSymlink {
 		var err error
 		if link, err = os.Readlink(path); err != nil {
-			return fmt.Errorf("writeTarGz: error resolving symlink %s: %w", path, err)
+			return fmt.Errorf("writeTarball: error resolving symlink %s: %w", path, err)
 		}
 	}
 
 	header, err := tar.FileInfoHeader(fileInfo, link)
 	if err != nil {
-		return fmt.Errorf("writeTarGz: error getting file info header: %w", err)
+		return fmt.Errorf("writeTarball: error getting file info header: %w", err)
 	}
 	header.Name = strings.TrimPrefix(path, prefix)
 
 	err = tarWriter.WriteHeader(header)
 	if err != nil {
-		return fmt.Errorf("writeTarGz: error writing file info header: %w", err)
+		return fmt.Errorf("writeTarball: error writing file info header: %w", err)
 	}
 
 	if !fileInfo.Mode().IsRegular() {
@@ -120,13 +134,13 @@ func writeTarGz(path string, tarWriter *tar.Writer, prefix string) error {
 
 	file, err := os.Open(path)
 	if err != nil {
-		return fmt.Errorf("writeTarGz: error opening %s: %w", path, err)
+		return fmt.Errorf("writeTarball: error opening %s: %w", path, err)
 	}
 	defer file.Close()
 
 	_, err = io.Copy(tarWriter, file)
 	if err != nil {
-		return fmt.Errorf("writeTarGz: error copying %s to tar writer: %w", path, err)
+		return fmt.Errorf("writeTarball: error copying %s to tar writer: %w", path, err)
 	}
 
 	return nil

cmd/backup/config.go

@@ -7,9 +7,9 @@ import (
 	"crypto/x509"
 	"encoding/pem"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"regexp"
+	"strconv"
 	"time"
 )
 
@@ -24,12 +24,12 @@ type Config struct {
 	AwsEndpointCACert             CertDecoder     `envconfig:"AWS_ENDPOINT_CA_CERT"`
 	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"`
+	AwsPartSize                   int64           `split_words:"true"`
+	BackupCompression             CompressionType `split_words:"true" default:"gz"`
 	BackupSources                 string          `split_words:"true" default:"/backup"`
-	BackupFilename                string        `split_words:"true" default:"backup-%Y-%m-%dT%H-%M-%S.tar.gz"`
+	BackupFilename                string          `split_words:"true" default:"backup-%Y-%m-%dT%H-%M-%S.{{ .Extension }}"`
 	BackupFilenameExpand          bool            `split_words:"true"`
 	BackupLatestSymlink           string          `split_words:"true"`
 	BackupArchive                 string          `split_words:"true" default:"/archive"`
@@ -39,6 +39,7 @@ type Config struct {
 	BackupStopContainerLabel      string          `split_words:"true" default:"true"`
 	BackupFromSnapshot            bool            `split_words:"true"`
 	BackupExcludeRegexp           RegexpDecoder   `split_words:"true"`
+	BackupSkipBackendsFromPrune   []string        `split_words:"true"`
 	GpgPassphrase                 string          `split_words:"true"`
 	NotificationURLs              []string        `envconfig:"NOTIFICATION_URLS"`
 	NotificationLevel             string          `split_words:"true" default:"error"`
@@ -68,17 +69,29 @@ type Config struct {
 	AzureStorageContainerName     string          `split_words:"true"`
 	AzureStoragePath              string          `split_words:"true"`
 	AzureStorageEndpoint          string          `split_words:"true" default:"https://{{ .AccountName }}.blob.core.windows.net/"`
+	DropboxEndpoint               string          `split_words:"true" default:"https://api.dropbox.com/"`
+	DropboxOAuth2Endpoint         string          `envconfig:"DROPBOX_OAUTH2_ENDPOINT" default:"https://api.dropbox.com/"`
+	DropboxRefreshToken           string          `split_words:"true"`
+	DropboxAppKey                 string          `split_words:"true"`
+	DropboxAppSecret              string          `split_words:"true"`
+	DropboxRemotePath             string          `split_words:"true"`
+	DropboxConcurrencyLevel       NaturalNumber   `split_words:"true" default:"6"`
 }
 
-func (c *Config) resolveSecret(envVar string, secretPath string) (string, error) {
-	if secretPath == "" {
-		return envVar, nil
+type CompressionType string
+
+func (c *CompressionType) Decode(v string) error {
+	switch v {
+	case "gz", "zst":
+		*c = CompressionType(v)
+		return nil
+	default:
+		return fmt.Errorf("config: error decoding compression type %s", v)
 	}
-	data, err := os.ReadFile(secretPath)
-	if err != nil {
-		return "", fmt.Errorf("resolveSecret: error reading secret path: %w", err)
 }
-	return string(data), nil
+
+func (c *CompressionType) String() string {
+	return string(*c)
 }
 
 type CertDecoder struct {
@@ -89,7 +102,7 @@ func (c *CertDecoder) Decode(v string) error {
 	if v == "" {
 		return nil
 	}
-	content, err := ioutil.ReadFile(v)
+	content, err := os.ReadFile(v)
 	if err != nil {
 		content = []byte(v)
 	}
@@ -117,3 +130,21 @@ func (r *RegexpDecoder) Decode(v string) error {
 	*r = RegexpDecoder{Re: re}
 	return nil
 }
+
+type NaturalNumber int
+
+func (n *NaturalNumber) Decode(v string) error {
+	asInt, err := strconv.Atoi(v)
+	if err != nil {
+		return fmt.Errorf("config: error converting %s to int", v)
+	}
+	if asInt <= 0 {
+		return fmt.Errorf("config: expected a natural number, got %d", asInt)
+	}
+	*n = NaturalNumber(asInt)
+	return nil
+}
+
+func (n *NaturalNumber) Int() int {
+	return int(*n)
+}

cmd/backup/exec.go

@@ -10,7 +10,7 @@ import (
 	"bytes"
 	"context"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"os"
 	"strings"
 
@@ -21,7 +21,7 @@ import (
 	"golang.org/x/sync/errgroup"
 )
 
-func (s *script) exec(containerRef string, command string) ([]byte, []byte, error) {
+func (s *script) exec(containerRef string, command string, user string) ([]byte, []byte, error) {
 	args, _ := argv.Argv(command, nil, nil)
 	commandEnv := []string{
 		fmt.Sprintf("COMMAND_RUNTIME_ARCHIVE_FILEPATH=%s", s.file),
@@ -31,6 +31,7 @@ func (s *script) exec(containerRef string, command string) ([]byte, []byte, erro
 		AttachStdin:  true,
 		AttachStderr: true,
 		Env:          commandEnv,
+		User:         user,
 	})
 	if err != nil {
 		return nil, nil, fmt.Errorf("exec: error creating container exec: %w", err)
@@ -50,19 +51,15 @@ func (s *script) exec(containerRef string, command string) ([]byte, []byte, erro
 		outputDone <- err
 	}()
 
-	select {
-	case err := <-outputDone:
-		if err != nil {
+	if <-outputDone != nil {
 		return nil, nil, fmt.Errorf("exec: error demultiplexing output: %w", err)
 	}
-		break
-	}
 
-	stdout, err := ioutil.ReadAll(&outBuf)
+	stdout, err := io.ReadAll(&outBuf)
 	if err != nil {
 		return nil, nil, fmt.Errorf("exec: error reading stdout: %w", err)
 	}
-	stderr, err := ioutil.ReadAll(&errBuf)
+	stderr, err := io.ReadAll(&errBuf)
 	if err != nil {
 		return nil, nil, fmt.Errorf("exec: error reading stderr: %w", err)
 	}
@@ -90,7 +87,6 @@ func (s *script) runLabeledCommands(label string) error {
 		})
 	}
 	containersWithCommand, err := s.cli.ContainerList(context.Background(), types.ContainerListOptions{
-		Quiet:   true,
 		Filters: filters.NewArgs(f...),
 	})
 	if err != nil {
@@ -104,7 +100,6 @@ func (s *script) runLabeledCommands(label string) error {
 			Value: "docker-volume-backup.exec-pre",
 		}
 		deprecatedContainers, err := s.cli.ContainerList(context.Background(), types.ContainerListOptions{
-			Quiet:   true,
 			Filters: filters.NewArgs(f...),
 		})
 		if err != nil {
@@ -122,7 +117,6 @@ func (s *script) runLabeledCommands(label string) error {
 			Value: "docker-volume-backup.exec-post",
 		}
 		deprecatedContainers, err := s.cli.ContainerList(context.Background(), types.ContainerListOptions{
-			Quiet:   true,
 			Filters: filters.NewArgs(f...),
 		})
 		if err != nil {
@@ -154,13 +148,16 @@ func (s *script) runLabeledCommands(label string) error {
 		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"]
+				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"]
+				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)
+			userLabelName := fmt.Sprintf("%s.user", label)
+			user := c.Labels[userLabelName]
+
+			s.logger.Info(fmt.Sprintf("Running %s command %s for container %s", label, cmd, strings.TrimPrefix(c.Names[0], "/")))
+			stdout, stderr, err := s.exec(c.ID, cmd, user)
 			if s.c.ExecForwardOutput {
 				os.Stderr.Write(stderr)
 				os.Stdout.Write(stdout)

cmd/backup/hooks.go

@@ -4,10 +4,9 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"sort"
-
-	"github.com/offen/docker-volume-backup/internal/utilities"
 )
 
 // hook contains a queued action that can be trigger them when the script
@@ -52,7 +51,7 @@ func (s *script) runHooks(err error) error {
 		}
 	}
 	if len(actionErrors) != 0 {
-		return utilities.Join(actionErrors...)
+		return errors.Join(actionErrors...)
 	}
 	return nil
 }

cmd/backup/lock.go

@@ -18,7 +18,7 @@ import (
 func (s *script) lock(lockfile string) (func() error, error) {
 	start := time.Now()
 	defer func() {
-		s.stats.LockedTime = time.Now().Sub(start)
+		s.stats.LockedTime = time.Since(start)
 	}()
 
 	retry := time.NewTicker(5 * time.Second)
@@ -41,9 +41,11 @@ func (s *script) lock(lockfile string) (func() error, error) {
 		}
 
 		if !s.encounteredLock {
-			s.logger.Infof(
+			s.logger.Info(
+				fmt.Sprintf(
 					"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
 		}

cmd/backup/main.go

@@ -4,6 +4,7 @@
 package main
 
 import (
+	"fmt"
 	"os"
 )
 
@@ -14,14 +15,16 @@ func main() {
 	}
 
 	unlock, err := s.lock("/var/lock/dockervolumebackup.lock")
-	defer unlock()
+	defer s.must(unlock())
 	s.must(err)
 
 	defer func() {
 		if pArg := recover(); pArg != nil {
 			if err, ok := pArg.(error); ok {
 				if hookErr := s.runHooks(err); hookErr != nil {
-					s.logger.Errorf("An error occurred calling the registered hooks: %s", hookErr)
+					s.logger.Error(
+						fmt.Sprintf("An error occurred calling the registered hooks: %s", hookErr),
+					)
 				}
 				os.Exit(1)
 			}
@@ -29,9 +32,11 @@ func main() {
 		}
 
 		if err := s.runHooks(nil); err != nil {
-			s.logger.Errorf(
+			s.logger.Error(
+				fmt.Sprintf(
 					"Backup procedure ran successfully, but an error ocurred calling the registered hooks: %v",
 					err,
+				),
 			)
 			os.Exit(1)
 		}

cmd/backup/notifications.go

@@ -6,13 +6,13 @@ package main
 import (
 	"bytes"
 	_ "embed"
+	"errors"
 	"fmt"
 	"os"
 	"text/template"
 	"time"
 
 	sTypes "github.com/containrrr/shoutrrr/pkg/types"
-	"github.com/offen/docker-volume-backup/internal/utilities"
 )
 
 //go:embed notifications.tmpl
@@ -69,7 +69,7 @@ func (s *script) sendNotification(title, body string) error {
 		}
 	}
 	if len(errs) != 0 {
-		return fmt.Errorf("sendNotification: error sending message: %w", utilities.Join(errs...))
+		return fmt.Errorf("sendNotification: error sending message: %w", errors.Join(errs...))
 	}
 	return nil
 }

cmd/backup/script.go

@@ -4,35 +4,40 @@
 package main
 
 import (
+	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"io"
 	"io/fs"
+	"log/slog"
 	"os"
 	"path"
 	"path/filepath"
+	"slices"
+	"strings"
 	"text/template"
 	"time"
 
 	"github.com/offen/docker-volume-backup/internal/storage"
 	"github.com/offen/docker-volume-backup/internal/storage/azure"
+	"github.com/offen/docker-volume-backup/internal/storage/dropbox"
 	"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/ProtonMail/go-crypto/openpgp"
 	"github.com/containrrr/shoutrrr"
 	"github.com/containrrr/shoutrrr/pkg/router"
 	"github.com/docker/docker/api/types"
+	ctr "github.com/docker/docker/api/types/container"
 	"github.com/docker/docker/api/types/filters"
 	"github.com/docker/docker/api/types/swarm"
 	"github.com/docker/docker/client"
-	"github.com/kelseyhightower/envconfig"
 	"github.com/leekchan/timeutil"
+	"github.com/offen/envconfig"
 	"github.com/otiai10/copy"
-	"github.com/sirupsen/logrus"
-	"golang.org/x/crypto/openpgp"
 	"golang.org/x/sync/errgroup"
 )
 
@@ -41,7 +46,7 @@ import (
 type script struct {
 	cli       *client.Client
 	storages  []storage.Backend
-	logger    *logrus.Logger
+	logger    *slog.Logger
 	sender    *router.ServiceRouter
 	template  *template.Template
 	hooks     []hook
@@ -63,12 +68,7 @@ func newScript() (*script, error) {
 	stdOut, logBuffer := buffer(os.Stdout)
 	s := &script{
 		c:      &Config{},
-		logger: &logrus.Logger{
-			Out:       stdOut,
-			Formatter: new(logrus.TextFormatter),
-			Hooks:     make(logrus.LevelHooks),
-			Level:     logrus.InfoLevel,
-		},
+		logger: slog.New(slog.NewTextHandler(stdOut, nil)),
 		stats: &Stats{
 			StartTime: time.Now(),
 			LogOutput: logBuffer,
@@ -78,6 +78,7 @@ func newScript() (*script, error) {
 				"SSH":     {},
 				"Local":   {},
 				"Azure":   {},
+				"Dropbox": {},
 			},
 		},
 	}
@@ -88,11 +89,47 @@ func newScript() (*script, error) {
 		return nil
 	})
 
+	envconfig.Lookup = func(key string) (string, bool) {
+		value, okValue := os.LookupEnv(key)
+		location, okFile := os.LookupEnv(key + "_FILE")
+
+		switch {
+		case okValue && !okFile: // only value
+			return value, true
+		case !okValue && okFile: // only file
+			contents, err := os.ReadFile(location)
+			if err != nil {
+				s.must(fmt.Errorf("newScript: failed to read %s! Error: %s", location, err))
+				return "", false
+			}
+			return string(contents), true
+		case okValue && okFile: // both
+			s.must(fmt.Errorf("newScript: both %s and %s are set!", key, key+"_FILE"))
+			return "", false
+		default: // neither, ignore
+			return "", false
+		}
+	}
+
 	if err := envconfig.Process("", s.c); err != nil {
 		return nil, fmt.Errorf("newScript: failed to process configuration values: %w", err)
 	}
 
 	s.file = path.Join("/tmp", s.c.BackupFilename)
+
+	tmplFileName, tErr := template.New("extension").Parse(s.file)
+	if tErr != nil {
+		return nil, fmt.Errorf("newScript: unable to parse backup file extension template: %w", tErr)
+	}
+
+	var bf bytes.Buffer
+	if tErr := tmplFileName.Execute(&bf, map[string]string{
+		"Extension": fmt.Sprintf("tar.%s", s.c.BackupCompression),
+	}); tErr != nil {
+		return nil, fmt.Errorf("newScript: error executing backup file extension template: %w", tErr)
+	}
+	s.file = bf.String()
+
 	if s.c.BackupFilenameExpand {
 		s.file = os.ExpandEnv(s.file)
 		s.c.BackupLatestSymlink = os.ExpandEnv(s.c.BackupLatestSymlink)
@@ -110,31 +147,22 @@ func newScript() (*script, error) {
 		s.cli = cli
 	}
 
-	logFunc := func(logType storage.LogLevel, context string, msg string, params ...interface{}) {
+	logFunc := func(logType storage.LogLevel, context string, msg string, params ...any) {
 		switch logType {
 		case storage.LogLevelWarning:
-			s.logger.Warnf("["+context+"] "+msg, params...)
+			s.logger.Warn(fmt.Sprintf(msg, params...), "storage", context)
 		case storage.LogLevelError:
-			s.logger.Errorf("["+context+"] "+msg, params...)
-		case storage.LogLevelInfo:
+			s.logger.Error(fmt.Sprintf(msg, params...), "storage", context)
 		default:
-			s.logger.Infof("["+context+"] "+msg, params...)
+			s.logger.Info(fmt.Sprintf(msg, params...), "storage", context)
 		}
 	}
 
 	if s.c.AwsS3BucketName != "" {
-		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,
+			AccessKeyID:      s.c.AwsAccessKeyID,
+			SecretAccessKey:  s.c.AwsSecretAccessKey,
 			IamRoleEndpoint:  s.c.AwsIamRoleEndpoint,
 			EndpointProto:    s.c.AwsEndpointProto,
 			EndpointInsecure: s.c.AwsEndpointInsecure,
@@ -142,9 +170,10 @@ func newScript() (*script, error) {
 			BucketName:       s.c.AwsS3BucketName,
 			StorageClass:     s.c.AwsStorageClass,
 			CACert:           s.c.AwsEndpointCACert.Cert,
+			PartSize:         s.c.AwsPartSize,
 		}
 		if s3Backend, err := s3.NewStorageBackend(s3Config, logFunc); err != nil {
-			return nil, err
+			return nil, fmt.Errorf("newScript: error creating s3 storage backend: %w", err)
 		} else {
 			s.storages = append(s.storages, s3Backend)
 		}
@@ -159,7 +188,7 @@ func newScript() (*script, error) {
 			RemotePath:  s.c.WebdavPath,
 		}
 		if webdavBackend, err := webdav.NewStorageBackend(webDavConfig, logFunc); err != nil {
-			return nil, err
+			return nil, fmt.Errorf("newScript: error creating webdav storage backend: %w", err)
 		} else {
 			s.storages = append(s.storages, webdavBackend)
 		}
@@ -176,7 +205,7 @@ func newScript() (*script, error) {
 			RemotePath:         s.c.SSHRemotePath,
 		}
 		if sshBackend, err := ssh.NewStorageBackend(sshConfig, logFunc); err != nil {
-			return nil, err
+			return nil, fmt.Errorf("newScript: error creating ssh storage backend: %w", err)
 		} else {
 			s.storages = append(s.storages, sshBackend)
 		}
@@ -201,11 +230,28 @@ func newScript() (*script, error) {
 		}
 		azureBackend, err := azure.NewStorageBackend(azureConfig, logFunc)
 		if err != nil {
-			return nil, err
+			return nil, fmt.Errorf("newScript: error creating azure storage backend: %w", err)
 		}
 		s.storages = append(s.storages, azureBackend)
 	}
 
+	if s.c.DropboxRefreshToken != "" && s.c.DropboxAppKey != "" && s.c.DropboxAppSecret != "" {
+		dropboxConfig := dropbox.Config{
+			Endpoint:         s.c.DropboxEndpoint,
+			OAuth2Endpoint:   s.c.DropboxOAuth2Endpoint,
+			RefreshToken:     s.c.DropboxRefreshToken,
+			AppKey:           s.c.DropboxAppKey,
+			AppSecret:        s.c.DropboxAppSecret,
+			RemotePath:       s.c.DropboxRemotePath,
+			ConcurrencyLevel: s.c.DropboxConcurrencyLevel.Int(),
+		}
+		dropboxBackend, err := dropbox.NewStorageBackend(dropboxConfig, logFunc)
+		if err != nil {
+			return nil, fmt.Errorf("newScript: error creating dropbox storage backend: %w", err)
+		}
+		s.storages = append(s.storages, dropboxBackend)
+	}
+
 	if s.c.EmailNotificationRecipient != "" {
 		emailURL := fmt.Sprintf(
 			"smtp://%s:%s@%s:%d/?from=%s&to=%s",
@@ -280,9 +326,7 @@ func (s *script) stopContainers() (func() error, error) {
 		return noop, nil
 	}
 
-	allContainers, err := s.cli.ContainerList(context.Background(), types.ContainerListOptions{
-		Quiet: true,
-	})
+	allContainers, err := s.cli.ContainerList(context.Background(), types.ContainerListOptions{})
 	if err != nil {
 		return noop, fmt.Errorf("stopContainers: error querying for containers: %w", err)
 	}
@@ -292,7 +336,6 @@ func (s *script) stopContainers() (func() error, error) {
 		s.c.BackupStopContainerLabel,
 	)
 	containersToStop, err := s.cli.ContainerList(context.Background(), types.ContainerListOptions{
-		Quiet: true,
 		Filters: filters.NewArgs(filters.KeyValuePair{
 			Key:   "label",
 			Value: containerLabel,
@@ -307,17 +350,19 @@ func (s *script) stopContainers() (func() error, error) {
 		return noop, nil
 	}
 
-	s.logger.Infof(
+	s.logger.Info(
+		fmt.Sprintf(
 			"Stopping %d container(s) labeled `%s` out of %d running container(s).",
 			len(containersToStop),
 			containerLabel,
 			len(allContainers),
+		),
 	)
 
 	var stoppedContainers []types.Container
 	var stopErrors []error
 	for _, container := range containersToStop {
-		if err := s.cli.ContainerStop(context.Background(), container.ID, nil); err != nil {
+		if err := s.cli.ContainerStop(context.Background(), container.ID, ctr.StopOptions{}); err != nil {
 			stopErrors = append(stopErrors, err)
 		} else {
 			stoppedContainers = append(stoppedContainers, container)
@@ -329,7 +374,7 @@ func (s *script) stopContainers() (func() error, error) {
 		stopError = fmt.Errorf(
 			"stopContainers: %d error(s) stopping containers: %w",
 			len(stopErrors),
-			utilities.Join(stopErrors...),
+			errors.Join(stopErrors...),
 		)
 	}
 
@@ -366,7 +411,7 @@ func (s *script) stopContainers() (func() error, error) {
 				if serviceMatch.ID == "" {
 					return fmt.Errorf("stopContainers: couldn't find service with name %s", serviceName)
 				}
-				serviceMatch.Spec.TaskTemplate.ForceUpdate = 1
+				serviceMatch.Spec.TaskTemplate.ForceUpdate += 1
 				if _, err := s.cli.ServiceUpdate(
 					context.Background(), serviceMatch.ID,
 					serviceMatch.Version, serviceMatch.Spec, types.ServiceUpdateOptions{},
@@ -380,12 +425,14 @@ func (s *script) stopContainers() (func() error, error) {
 			return fmt.Errorf(
 				"stopContainers: %d error(s) restarting containers and services: %w",
 				len(restartErrors),
-				utilities.Join(restartErrors...),
+				errors.Join(restartErrors...),
 			)
 		}
-		s.logger.Infof(
+		s.logger.Info(
+			fmt.Sprintf(
 				"Restarted %d container(s) and the matching service(s).",
 				len(stoppedContainers),
+			),
 		)
 		return nil
 	}, stopError
@@ -409,7 +456,9 @@ func (s *script) createArchive() error {
 			if err := remove(backupSources); err != nil {
 				return fmt.Errorf("createArchive: error removing snapshot: %w", err)
 			}
-			s.logger.Infof("Removed snapshot `%s`.", backupSources)
+			s.logger.Info(
+				fmt.Sprintf("Removed snapshot `%s`.", backupSources),
+			)
 			return nil
 		})
 		if err := copy.Copy(s.c.BackupSources, backupSources, copy.Options{
@@ -418,7 +467,9 @@ func (s *script) createArchive() error {
 		}); err != nil {
 			return fmt.Errorf("createArchive: error creating snapshot: %w", err)
 		}
-		s.logger.Infof("Created snapshot of `%s` at `%s`.", s.c.BackupSources, backupSources)
+		s.logger.Info(
+			fmt.Sprintf("Created snapshot of `%s` at `%s`.", s.c.BackupSources, backupSources),
+		)
 	}
 
 	tarFile := s.file
@@ -426,7 +477,9 @@ func (s *script) createArchive() error {
 		if err := remove(tarFile); err != nil {
 			return fmt.Errorf("createArchive: error removing tar file: %w", err)
 		}
-		s.logger.Infof("Removed tar file `%s`.", tarFile)
+		s.logger.Info(
+			fmt.Sprintf("Removed tar file `%s`.", tarFile),
+		)
 		return nil
 	})
 
@@ -450,11 +503,13 @@ func (s *script) createArchive() error {
 		return fmt.Errorf("createArchive: error walking filesystem tree: %w", err)
 	}
 
-	if err := createArchive(filesEligibleForBackup, backupSources, tarFile); err != nil {
+	if err := createArchive(filesEligibleForBackup, backupSources, tarFile, s.c.BackupCompression.String()); err != nil {
 		return fmt.Errorf("createArchive: error compressing backup folder: %w", err)
 	}
 
-	s.logger.Infof("Created backup of `%s` at `%s`.", backupSources, tarFile)
+	s.logger.Info(
+		fmt.Sprintf("Created backup of `%s` at `%s`.", backupSources, tarFile),
+	)
 	return nil
 }
 
@@ -471,7 +526,9 @@ func (s *script) encryptArchive() error {
 		if err := remove(gpgFile); err != nil {
 			return fmt.Errorf("encryptArchive: error removing gpg file: %w", err)
 		}
-		s.logger.Infof("Removed GPG file `%s`.", gpgFile)
+		s.logger.Info(
+			fmt.Sprintf("Removed GPG file `%s`.", gpgFile),
+		)
 		return nil
 	})
 
@@ -501,7 +558,9 @@ func (s *script) encryptArchive() error {
 	}
 
 	s.file = gpgFile
-	s.logger.Infof("Encrypted backup using given passphrase, saving as `%s`.", s.file)
+	s.logger.Info(
+		fmt.Sprintf("Encrypted backup using given passphrase, saving as `%s`.", s.file),
+	)
 	return nil
 }
 
@@ -548,6 +607,12 @@ func (s *script) pruneBackups() error {
 	for _, backend := range s.storages {
 		b := backend
 		eg.Go(func() error {
+			if skipPrune(b.Name(), s.c.BackupSkipBackendsFromPrune) {
+				s.logger.Info(
+					fmt.Sprintf("Skipping pruning for backend `%s`.", b.Name()),
+				)
+				return nil
+			}
 			stats, err := b.Prune(deadline, s.c.BackupPruningPrefix)
 			if err != nil {
 				return err
@@ -573,7 +638,20 @@ func (s *script) pruneBackups() error {
 // is non-nil.
 func (s *script) must(err error) {
 	if err != nil {
-		s.logger.Errorf("Fatal error running backup: %s", err)
+		s.logger.Error(
+			fmt.Sprintf("Fatal error running backup: %s", err),
+		)
 		panic(err)
 	}
 }
+
+// skipPrune returns true if the given backend name is contained in the
+// list of skipped backends.
+func skipPrune(name string, skippedBackends []string) bool {
+	return slices.ContainsFunc(
+		skippedBackends,
+		func(b string) bool {
+			return strings.EqualFold(b, name) // ignore case on both sides
+		},
+	)
+}

docs/NOTIFICATION-TEMPLATES.md

@@ -25,7 +25,7 @@ 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`, `WebDAV`, `Azure` or `SSH`:
+    * `Local`, `S3`, `WebDAV`, `Azure`, `Dropbox` 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

go.mod

@@ -1,74 +1,71 @@
 module github.com/offen/docker-volume-backup
 
-go 1.19
+go 1.21
 
 require (
-	github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.2.0
-	github.com/Azure/azure-sdk-for-go/sdk/storage/azblob v0.6.1
-	github.com/containrrr/shoutrrr v0.5.2
+	github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.3.0
+	github.com/Azure/azure-sdk-for-go/sdk/storage/azblob v1.1.0
+	github.com/containrrr/shoutrrr v0.7.1
 	github.com/cosiner/argv v0.1.0
-	github.com/docker/docker v20.10.11+incompatible
+	github.com/docker/docker v24.0.5+incompatible
 	github.com/gofrs/flock v0.8.1
-	github.com/kelseyhightower/envconfig v1.4.0
+	github.com/klauspost/compress v1.16.7
 	github.com/leekchan/timeutil v0.0.0-20150802142658-28917288c48d
-	github.com/minio/minio-go/v7 v7.0.44
-	github.com/otiai10/copy v1.7.0
-	github.com/pkg/sftp v1.13.5
-	github.com/sirupsen/logrus v1.9.0
-	github.com/studio-b12/gowebdav v0.0.0-20220128162035-c7b1ff8a5e62
-	golang.org/x/crypto v0.3.0
-	golang.org/x/sync v0.0.0-20220601150217-0de741cfad7f
+	github.com/minio/minio-go/v7 v7.0.62
+	github.com/offen/envconfig v1.5.0
+	github.com/otiai10/copy v1.11.0
+	github.com/pkg/sftp v1.13.6
+	github.com/studio-b12/gowebdav v0.9.0
+	golang.org/x/crypto v0.12.0
+	golang.org/x/oauth2 v0.0.0-20221014153046-6fdb5e3db783
+	golang.org/x/sync v0.3.0
 )
 
 require (
-	github.com/Azure/azure-sdk-for-go/sdk/azcore v1.1.4 // indirect
-	github.com/Azure/azure-sdk-for-go/sdk/internal v1.0.1 // indirect
-	github.com/AzureAD/microsoft-authentication-library-for-go v0.7.0 // indirect
+	github.com/cloudflare/circl v1.3.3 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	google.golang.org/appengine v1.6.7 // indirect
+	google.golang.org/protobuf v1.28.1 // indirect
+)
+
+require (
+	github.com/Azure/azure-sdk-for-go/sdk/azcore v1.6.0 // indirect
+	github.com/Azure/azure-sdk-for-go/sdk/internal v1.3.0 // indirect
+	github.com/AzureAD/microsoft-authentication-library-for-go v1.0.0 // 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/ProtonMail/go-crypto v0.0.0-20230717121422-5aa5874ade95
+	github.com/docker/distribution v2.8.2+incompatible // indirect
 	github.com/docker/go-connections v0.4.0 // indirect
 	github.com/docker/go-units v0.4.0 // indirect
-	github.com/dustin/go-humanize v1.0.0 // indirect
-	github.com/fatih/color v1.10.0 // indirect
-	github.com/fsnotify/fsnotify v1.4.9 // indirect
+	github.com/dropbox/dropbox-sdk-go-unofficial/v6 v6.0.5
+	github.com/dustin/go-humanize v1.0.1 // indirect
+	github.com/fatih/color v1.13.0 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
-	github.com/golang-jwt/jwt/v4 v4.4.2 // indirect
-	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/golang-jwt/jwt/v4 v4.5.0 // 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 v1.15.12 // indirect
-	github.com/klauspost/cpuid/v2 v2.2.1 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.5 // indirect
 	github.com/kr/fs v0.1.0 // indirect
-	github.com/kr/text v0.2.0 // indirect
 	github.com/kylelemons/godebug v1.1.0 // indirect
-	github.com/mattn/go-colorable v0.1.8 // indirect
-	github.com/mattn/go-isatty v0.0.12 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.16 // indirect
 	github.com/minio/md5-simd v1.1.2 // indirect
-	github.com/minio/sha256-simd v1.0.0 // indirect
+	github.com/minio/sha256-simd v1.0.1 // 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 v1.0.3-0.20211202183452-c5a74bcca799 // indirect
-	github.com/pkg/browser v0.0.0-20210115035449-ce105d075bb4 // indirect
+	github.com/pkg/browser v0.0.0-20210911075715-681adbf594b8 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
-	github.com/rs/xid v1.4.0 // indirect
-	golang.org/x/net v0.2.0 // indirect
-	golang.org/x/sys v0.2.0 // indirect
-	golang.org/x/text v0.4.0 // indirect
-	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // 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
+	github.com/rs/xid v1.5.0 // indirect
+	github.com/sirupsen/logrus v1.9.3 // indirect
+	golang.org/x/net v0.14.0 // indirect
+	golang.org/x/sys v0.11.0 // indirect
+	golang.org/x/text v0.12.0 // indirect
 	gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect
-	gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 // indirect
-	gopkg.in/yaml.v2 v2.4.0 // indirect
+	gotest.tools/v3 v3.0.3 // indirect
 )

internal/storage/azure/azure.go

@@ -6,6 +6,7 @@ package azure
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -18,7 +19,6 @@ import (
 	"github.com/Azure/azure-sdk-for-go/sdk/storage/azblob"
 	"github.com/Azure/azure-sdk-for-go/sdk/storage/azblob/container"
 	"github.com/offen/docker-volume-backup/internal/storage"
-	"github.com/offen/docker-volume-backup/internal/utilities"
 )
 
 type azureBlobStorage struct {
@@ -132,24 +132,24 @@ func (b *azureBlobStorage) Prune(deadline time.Time, pruningPrefix string) (*sto
 		Pruned: uint(len(matches)),
 	}
 
-	if err := b.DoPrune(b.Name(), len(matches), int(totalCount), "Azure Blob Storage backup(s)", func() error {
+	if err := b.DoPrune(b.Name(), len(matches), int(totalCount), func() error {
 		wg := sync.WaitGroup{}
 		wg.Add(len(matches))
-		var errors []error
+		var errs []error
 
 		for _, match := range matches {
 			name := match
 			go func() {
 				_, err := b.client.DeleteBlob(context.Background(), b.containerName, name, nil)
 				if err != nil {
-					errors = append(errors, err)
+					errs = append(errs, err)
 				}
 				wg.Done()
 			}()
 		}
 		wg.Wait()
-		if len(errors) != 0 {
-			return utilities.Join(errors...)
+		if len(errs) != 0 {
+			return errors.Join(errs...)
 		}
 		return nil
 	}); err != nil {

internal/storage/dropbox/dropbox.go

@@ -0,0 +1,260 @@
+package dropbox
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"net/url"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/dropbox/dropbox-sdk-go-unofficial/v6/dropbox"
+	"github.com/dropbox/dropbox-sdk-go-unofficial/v6/dropbox/files"
+	"github.com/offen/docker-volume-backup/internal/storage"
+	"golang.org/x/oauth2"
+)
+
+type dropboxStorage struct {
+	*storage.StorageBackend
+	client           files.Client
+	concurrencyLevel int
+}
+
+// Config allows to configure a Dropbox storage backend.
+type Config struct {
+	Endpoint         string
+	OAuth2Endpoint   string
+	RefreshToken     string
+	AppKey           string
+	AppSecret        string
+	RemotePath       string
+	ConcurrencyLevel int
+}
+
+// NewStorageBackend creates and initializes a new Dropbox storage backend.
+func NewStorageBackend(opts Config, logFunc storage.Log) (storage.Backend, error) {
+	tokenUrl, _ := url.JoinPath(opts.OAuth2Endpoint, "oauth2/token")
+
+	conf := &oauth2.Config{
+		ClientID:     opts.AppKey,
+		ClientSecret: opts.AppSecret,
+		Endpoint: oauth2.Endpoint{
+			TokenURL: tokenUrl,
+		},
+	}
+
+	logFunc(storage.LogLevelInfo, "Dropbox", "Fetching fresh access token for Dropbox storage backend.")
+	tkSource := conf.TokenSource(context.Background(), &oauth2.Token{RefreshToken: opts.RefreshToken})
+	token, err := tkSource.Token()
+	if err != nil {
+		return nil, fmt.Errorf("(*dropboxStorage).NewStorageBackend: Error refreshing token: %w", err)
+	}
+
+	dbxConfig := dropbox.Config{
+		Token: token.AccessToken,
+	}
+
+	if opts.Endpoint != "https://api.dropbox.com/" {
+		dbxConfig.URLGenerator = func(hostType string, namespace string, route string) string {
+			return fmt.Sprintf("%s/%d/%s/%s", opts.Endpoint, 2, namespace, route)
+		}
+	}
+
+	client := files.New(dbxConfig)
+
+	if opts.ConcurrencyLevel < 1 {
+		logFunc(storage.LogLevelWarning, "Dropbox", "Concurrency level must be at least 1! Using 1 instead of %d.", opts.ConcurrencyLevel)
+		opts.ConcurrencyLevel = 1
+	}
+
+	return &dropboxStorage{
+		StorageBackend: &storage.StorageBackend{
+			DestinationPath: opts.RemotePath,
+			Log:             logFunc,
+		},
+		client:           client,
+		concurrencyLevel: opts.ConcurrencyLevel,
+	}, nil
+}
+
+// Name returns the name of the storage backend
+func (b *dropboxStorage) Name() string {
+	return "Dropbox"
+}
+
+// Copy copies the given file to the WebDav storage backend.
+func (b *dropboxStorage) Copy(file string) error {
+	_, name := path.Split(file)
+
+	folderArg := files.NewCreateFolderArg(b.DestinationPath)
+	if _, err := b.client.CreateFolderV2(folderArg); err != nil {
+		switch err := err.(type) {
+		case files.CreateFolderV2APIError:
+			if err.EndpointError.Path.Tag != files.WriteErrorConflict {
+				return fmt.Errorf("(*dropboxStorage).Copy: Error creating directory '%s': %w", b.DestinationPath, err)
+			}
+			b.Log(storage.LogLevelInfo, b.Name(), "Destination path '%s' already exists, no new directory required.", b.DestinationPath)
+		default:
+			return fmt.Errorf("(*dropboxStorage).Copy: Error creating directory '%s': %w", b.DestinationPath, err)
+		}
+	}
+
+	r, err := os.Open(file)
+	if err != nil {
+		return fmt.Errorf("(*dropboxStorage).Copy: Error opening the file to be uploaded: %w", err)
+	}
+	defer r.Close()
+
+	// Start new upload session and get session id
+
+	b.Log(storage.LogLevelInfo, b.Name(), "Starting upload session for backup '%s' at path '%s'.", file, b.DestinationPath)
+
+	var sessionId string
+	uploadSessionStartArg := files.NewUploadSessionStartArg()
+	uploadSessionStartArg.SessionType = &files.UploadSessionType{Tagged: dropbox.Tagged{Tag: files.UploadSessionTypeConcurrent}}
+	if res, err := b.client.UploadSessionStart(uploadSessionStartArg, nil); err != nil {
+		return fmt.Errorf("(*dropboxStorage).Copy: Error starting the upload session: %w", err)
+	} else {
+		sessionId = res.SessionId
+	}
+
+	// Send the file in 148MB chunks (Dropbox API limit is 150MB, concurrent upload requires a multiple of 4MB though)
+	// Last append can be any size <= 150MB with Close=True
+
+	const chunkSize = 148 * 1024 * 1024 // 148MB
+	var offset uint64 = 0
+	var guard = make(chan struct{}, b.concurrencyLevel)
+	var errorChn = make(chan error, b.concurrencyLevel)
+	var EOFChn = make(chan bool, b.concurrencyLevel)
+	var mu sync.Mutex
+	var wg sync.WaitGroup
+
+loop:
+	for {
+		guard <- struct{}{} // limit concurrency
+		select {
+		case err := <-errorChn: // error from goroutine
+			return err
+		case <-EOFChn: // EOF from goroutine
+			wg.Wait() // wait for all goroutines to finish
+			break loop
+		default:
+		}
+
+		go func() {
+			defer func() {
+				wg.Done()
+				<-guard
+			}()
+			wg.Add(1)
+			chunk := make([]byte, chunkSize)
+
+			mu.Lock() // to preserve offset of chunks
+
+			select {
+			case <-EOFChn:
+				EOFChn <- true // put it back for outer loop
+				mu.Unlock()
+				return // already EOF
+			default:
+			}
+
+			bytesRead, err := r.Read(chunk)
+			if err != nil {
+				errorChn <- fmt.Errorf("(*dropboxStorage).Copy: Error reading the file to be uploaded: %w", err)
+				mu.Unlock()
+				return
+			}
+			chunk = chunk[:bytesRead]
+
+			uploadSessionAppendArg := files.NewUploadSessionAppendArg(
+				files.NewUploadSessionCursor(sessionId, offset),
+			)
+			isEOF := bytesRead < chunkSize
+			uploadSessionAppendArg.Close = isEOF
+			if isEOF {
+				EOFChn <- true
+			}
+			offset += uint64(bytesRead)
+
+			mu.Unlock()
+
+			if err := b.client.UploadSessionAppendV2(uploadSessionAppendArg, bytes.NewReader(chunk)); err != nil {
+				errorChn <- fmt.Errorf("(*dropboxStorage).Copy: Error appending the file to the upload session: %w", err)
+				return
+			}
+		}()
+	}
+
+	// Finish the upload session, commit the file (no new data added)
+
+	_, err = b.client.UploadSessionFinish(
+		files.NewUploadSessionFinishArg(
+			files.NewUploadSessionCursor(sessionId, 0),
+			files.NewCommitInfo(filepath.Join(b.DestinationPath, name)),
+		), nil)
+	if err != nil {
+		return fmt.Errorf("(*dropboxStorage).Copy: Error finishing the upload session: %w", err)
+	}
+
+	b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup '%s' at path '%s'.", file, b.DestinationPath)
+
+	return nil
+}
+
+// Prune rotates away backups according to the configuration and provided deadline for the Dropbox storage backend.
+func (b *dropboxStorage) Prune(deadline time.Time, pruningPrefix string) (*storage.PruneStats, error) {
+	var entries []files.IsMetadata
+	res, err := b.client.ListFolder(files.NewListFolderArg(b.DestinationPath))
+	if err != nil {
+		return nil, fmt.Errorf("(*webDavStorage).Prune: Error looking up candidates from remote storage: %w", err)
+	}
+	entries = append(entries, res.Entries...)
+
+	for res.HasMore {
+		res, err = b.client.ListFolderContinue(files.NewListFolderContinueArg(res.Cursor))
+		if err != nil {
+			return nil, fmt.Errorf("(*webDavStorage).Prune: Error looking up candidates from remote storage: %w", err)
+		}
+		entries = append(entries, res.Entries...)
+	}
+
+	var matches []*files.FileMetadata
+	var lenCandidates int
+	for _, candidate := range entries {
+		switch candidate := candidate.(type) {
+		case *files.FileMetadata:
+			if !strings.HasPrefix(candidate.Name, pruningPrefix) {
+				continue
+			}
+			lenCandidates++
+			if candidate.ServerModified.Before(deadline) {
+				matches = append(matches, candidate)
+			}
+		default:
+			continue
+		}
+	}
+
+	stats := &storage.PruneStats{
+		Total:  uint(lenCandidates),
+		Pruned: uint(len(matches)),
+	}
+
+	if err := b.DoPrune(b.Name(), len(matches), lenCandidates, func() error {
+		for _, match := range matches {
+			if _, err := b.client.DeleteV2(files.NewDeleteArg(filepath.Join(b.DestinationPath, match.Name))); err != nil {
+				return fmt.Errorf("(*dropboxStorage).Prune: Error removing file from Dropbox storage: %w", err)
+			}
+		}
+		return nil
+	}); err != nil {
+		return stats, err
+	}
+
+	return stats, nil
+}

internal/storage/local/local.go

@@ -4,6 +4,7 @@
 package local
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -12,7 +13,6 @@ import (
 	"time"
 
 	"github.com/offen/docker-volume-backup/internal/storage"
-	"github.com/offen/docker-volume-backup/internal/utilities"
 )
 
 type localStorage struct {
@@ -47,9 +47,9 @@ 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)
+		return fmt.Errorf("(*localStorage).Copy: Error copying file to archive: %w", err)
 	}
-	b.Log(storage.LogLevelInfo, b.Name(), "Stored copy of backup `%s` in local archive `%s`.", file, b.DestinationPath)
+	b.Log(storage.LogLevelInfo, b.Name(), "Stored copy of backup `%s` in `%s`.", file, b.DestinationPath)
 
 	if b.latestSymlink != "" {
 		symlink := path.Join(b.DestinationPath, b.latestSymlink)
@@ -116,7 +116,7 @@ func (b *localStorage) Prune(deadline time.Time, pruningPrefix string) (*storage
 		Pruned: uint(len(matches)),
 	}
 
-	if err := b.DoPrune(b.Name(), len(matches), len(candidates), "local backup(s)", func() error {
+	if err := b.DoPrune(b.Name(), len(matches), len(candidates), func() error {
 		var removeErrors []error
 		for _, match := range matches {
 			if err := os.Remove(match); err != nil {
@@ -125,9 +125,9 @@ func (b *localStorage) Prune(deadline time.Time, pruningPrefix string) (*storage
 		}
 		if len(removeErrors) != 0 {
 			return fmt.Errorf(
-				"(*localStorage).Prune: %d error(s) deleting local files, starting with: %w",
+				"(*localStorage).Prune: %d error(s) deleting files, starting with: %w",
 				len(removeErrors),
-				utilities.Join(removeErrors...),
+				errors.Join(removeErrors...),
 			)
 		}
 		return nil

internal/storage/s3/s3.go

@@ -8,6 +8,7 @@ import (
 	"crypto/x509"
 	"errors"
 	"fmt"
+	"os"
 	"path"
 	"path/filepath"
 	"time"
@@ -15,7 +16,6 @@ import (
 	"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 {
@@ -23,6 +23,7 @@ type s3Storage struct {
 	client       *minio.Client
 	bucket       string
 	storageClass string
+	partSize     int64
 }
 
 // Config contains values that define the configuration of a S3 backend.
@@ -36,6 +37,7 @@ type Config struct {
 	RemotePath       string
 	BucketName       string
 	StorageClass     string
+	PartSize         int64
 	CACert           *x509.Certificate
 }
 
@@ -90,6 +92,7 @@ func NewStorageBackend(opts Config, logFunc storage.Log) (storage.Backend, error
 		client:       mc,
 		bucket:       opts.BucketName,
 		storageClass: opts.StorageClass,
+		partSize:     opts.PartSize,
 	}, nil
 }
 
@@ -101,16 +104,37 @@ func (v *s3Storage) Name() string {
 // 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{
+	putObjectOptions := minio.PutObjectOptions{
 		ContentType:  "application/tar+gzip",
 		StorageClass: b.storageClass,
-	}); err != nil {
+	}
+
+	if b.partSize > 0 {
+		srcFileInfo, err := os.Stat(file)
+		if err != nil {
+			return fmt.Errorf("(*s3Storage).Copy: error reading the local file: %w", err)
+		}
+
+		_, partSize, _, err := minio.OptimalPartInfo(srcFileInfo.Size(), uint64(b.partSize*1024*1024))
+		if err != nil {
+			return fmt.Errorf("(*s3Storage).Copy: error computing the optimal s3 part size: %w", err)
+		}
+
+		putObjectOptions.PartSize = uint64(partSize)
+	}
+
+	if _, err := b.client.FPutObject(context.Background(), b.bucket, filepath.Join(b.DestinationPath, name), file, putObjectOptions); err != nil {
 		if errResp := minio.ToErrorResponse(err); errResp.Message != "" {
-			return fmt.Errorf("(*s3Storage).Copy: error uploading backup to remote storage: [Message]: '%s', [Code]: %s, [StatusCode]: %d", errResp.Message, errResp.Code, errResp.StatusCode)
+			return fmt.Errorf(
+				"(*s3Storage).Copy: error uploading backup to remote storage: [Message]: '%s', [Code]: %s, [StatusCode]: %d",
+				errResp.Message,
+				errResp.Code,
+				errResp.StatusCode,
+			)
 		}
 		return fmt.Errorf("(*s3Storage).Copy: error uploading backup to remote storage: %w", err)
 	}
+
 	b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup `%s` to bucket `%s`.", file, b.bucket)
 
 	return nil
@@ -129,7 +153,7 @@ func (b *s3Storage) Prune(deadline time.Time, pruningPrefix string) (*storage.Pr
 		lenCandidates++
 		if candidate.Err != nil {
 			return nil, fmt.Errorf(
-				"(*s3Storage).Prune: Error looking up candidates from remote storage! %w",
+				"(*s3Storage).Prune: error looking up candidates from remote storage! %w",
 				candidate.Err,
 			)
 		}
@@ -143,7 +167,7 @@ func (b *s3Storage) Prune(deadline time.Time, pruningPrefix string) (*storage.Pr
 		Pruned: uint(len(matches)),
 	}
 
-	if err := b.DoPrune(b.Name(), len(matches), lenCandidates, "remote backup(s)", func() error {
+	if err := b.DoPrune(b.Name(), len(matches), lenCandidates, func() error {
 		objectsCh := make(chan minio.ObjectInfo)
 		go func() {
 			for _, match := range matches {
@@ -159,7 +183,7 @@ func (b *s3Storage) Prune(deadline time.Time, pruningPrefix string) (*storage.Pr
 			}
 		}
 		if len(removeErrors) != 0 {
-			return utilities.Join(removeErrors...)
+			return errors.Join(removeErrors...)
 		}
 		return nil
 	}); err != nil {

internal/storage/ssh/ssh.go

@@ -7,7 +7,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"path"
 	"path/filepath"
@@ -46,7 +45,7 @@ func NewStorageBackend(opts Config, logFunc storage.Log) (storage.Backend, error
 	}
 
 	if _, err := os.Stat(opts.IdentityFile); err == nil {
-		key, err := ioutil.ReadFile(opts.IdentityFile)
+		key, err := os.ReadFile(opts.IdentityFile)
 		if err != nil {
 			return nil, errors.New("NewStorageBackend: error reading the private key")
 		}
@@ -75,7 +74,7 @@ func NewStorageBackend(opts Config, logFunc storage.Log) (storage.Backend, error
 	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)
+		return nil, fmt.Errorf("NewStorageBackend: error creating ssh client: %w", err)
 	}
 	_, _, err = sshClient.SendRequest("keepalive", false, nil)
 	if err != nil {
@@ -108,13 +107,13 @@ 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)
+		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)
+		return fmt.Errorf("(*sshStorage).Copy: error creating file: %w", err)
 	}
 	defer destination.Close()
 
@@ -124,7 +123,7 @@ func (b *sshStorage) Copy(file string) error {
 		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)
+				return fmt.Errorf("(*sshStorage).Copy: error uploading the file: %w", err)
 			}
 
 			if tot != len(chunk[:num]) {
@@ -135,12 +134,12 @@ func (b *sshStorage) Copy(file string) error {
 		}
 
 		if err != nil {
-			return fmt.Errorf("(*sshStorage).Copy: Error uploading the file to SSH storage: %w", err)
+			return fmt.Errorf("(*sshStorage).Copy: error uploading the file: %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)
+			return fmt.Errorf("(*sshStorage).Copy: error uploading the file: %w", err)
 		}
 
 		if tot != len(chunk[:num]) {
@@ -148,7 +147,7 @@ func (b *sshStorage) Copy(file string) error {
 		}
 	}
 
-	b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup `%s` to SSH storage '%s' at path '%s'.", file, b.hostName, b.DestinationPath)
+	b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup `%s` to '%s' at path '%s'.", file, b.hostName, b.DestinationPath)
 
 	return nil
 }
@@ -157,7 +156,7 @@ func (b *sshStorage) Copy(file string) error {
 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)
+		return nil, fmt.Errorf("(*sshStorage).Prune: error reading directory: %w", err)
 	}
 
 	var matches []string
@@ -175,10 +174,10 @@ func (b *sshStorage) Prune(deadline time.Time, pruningPrefix string) (*storage.P
 		Pruned: uint(len(matches)),
 	}
 
-	if err := b.DoPrune(b.Name(), len(matches), len(candidates), "SSH backup(s)", func() error {
+	if err := b.DoPrune(b.Name(), len(matches), len(candidates), 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 fmt.Errorf("(*sshStorage).Prune: error removing file: %w", err)
 			}
 		}
 		return nil

internal/storage/storage.go

@@ -29,7 +29,7 @@ const (
 	LogLevelError
 )
 
-type Log func(logType LogLevel, context string, msg string, params ...interface{})
+type Log func(logType LogLevel, context string, msg string, params ...any)
 
 // PruneStats is a wrapper struct for returning stats after pruning
 type PruneStats struct {
@@ -39,23 +39,22 @@ type PruneStats struct {
 
 // 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 {
+func (b *StorageBackend) DoPrune(context string, lenMatches, lenCandidates int, 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.",
+			"Pruned %d out of %d backups 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, "The current configuration would delete all %d existing backups.", lenMatches)
 		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)
+		b.Log(LogLevelInfo, context, "None of %d existing backups were pruned.", lenCandidates)
 	}
 	return nil
 }

internal/storage/webdav/webdav.go

@@ -69,18 +69,18 @@ func (b *webDavStorage) Name() string {
 func (b *webDavStorage) Copy(file string) error {
 	_, name := path.Split(file)
 	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)
+		return fmt.Errorf("(*webDavStorage).Copy: error creating directory '%s' on server: %w", b.DestinationPath, err)
 	}
 
 	r, err := os.Open(file)
 	if err != nil {
-		return fmt.Errorf("(*webDavStorage).Copy: Error opening the file to be uploaded: %w", err)
+		return fmt.Errorf("(*webDavStorage).Copy: error opening the file to be uploaded: %w", err)
 	}
 
 	if err := b.client.WriteStream(filepath.Join(b.DestinationPath, name), r, 0644); err != nil {
-		return fmt.Errorf("(*webDavStorage).Copy: Error uploading the file to WebDAV server: %w", err)
+		return fmt.Errorf("(*webDavStorage).Copy: error uploading the file: %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)
+	b.Log(storage.LogLevelInfo, b.Name(), "Uploaded a copy of backup '%s' to '%s' at path '%s'.", file, b.url, b.DestinationPath)
 
 	return nil
 }
@@ -89,7 +89,7 @@ func (b *webDavStorage) Copy(file string) error {
 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)
+		return nil, fmt.Errorf("(*webDavStorage).Prune: error looking up candidates from remote storage: %w", err)
 	}
 	var matches []fs.FileInfo
 	var lenCandidates int
@@ -108,10 +108,10 @@ func (b *webDavStorage) Prune(deadline time.Time, pruningPrefix string) (*storag
 		Pruned: uint(len(matches)),
 	}
 
-	if err := b.DoPrune(b.Name(), len(matches), lenCandidates, "WebDAV backup(s)", func() error {
+	if err := b.DoPrune(b.Name(), len(matches), lenCandidates, 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 fmt.Errorf("(*webDavStorage).Prune: error removing file: %w", err)
 			}
 		}
 		return nil

internal/utilities/util.go

@@ -1,24 +0,0 @@
-// 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, ", ") + "]")
-}

test/azure/run.sh

@@ -6,35 +6,61 @@ cd "$(dirname "$0")"
 . ../util.sh
 current_test=$(basename $(pwd))
 
-docker-compose up -d
+download_az () {
+  docker compose run --rm az_cli \
+    az storage blob download -f /dump/$1.tar.gz -c test-container -n path/to/backup/$1.tar.gz
+}
+
+docker compose up -d --quiet-pull
 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
+docker compose exec backup backup
 
 sleep 5
 
 expect_running_containers "3"
 
-docker-compose run --rm az_cli \
-  az storage blob download -f /dump/test.tar.gz -c test-container -n path/to/backup/test.tar.gz
+download_az "test"
 tar -xvf ./local/test.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
+BACKUP_RETENTION_DAYS="0" docker compose up -d
 sleep 5
 
-docker-compose exec backup backup
+docker compose exec backup backup
 
-docker-compose run --rm az_cli \
-  az storage blob download -f /dump/test.tar.gz -c test-container -n path/to/backup/test.tar.gz
+download_az "test"
 test -f ./local/test.tar.gz
 
 pass "Remote backups have not been deleted."
 
-docker-compose down --volumes
+# The third part of this test checks if old backups get deleted when the retention
+# is set to 7 days (which it should)
+
+BACKUP_RETENTION_DAYS="7" docker compose up -d
+sleep 5
+
+info "Create first backup with no prune"
+docker compose exec backup backup
+
+sudo date --set="14 days ago"
+
+docker compose run --rm az_cli \
+    az storage blob upload -f /dump/test.tar.gz -c test-container -n path/to/backup/test-old.tar.gz
+
+sudo date --set="14 days"
+
+info "Create second backup and prune"
+docker compose exec backup backup
+
+info "Download first backup which should be pruned"
+download_az "test-old" || true
+test ! -f ./local/test-old.tar.gz
+test -f ./local/test.tar.gz
+
+pass "Old remote backup has been pruned, new one is still present."
+
+docker compose down --volumes

test/certs/run.sh

@@ -24,7 +24,7 @@ openssl x509 -req -passin pass:test \
 
 openssl x509 -in minio.crt -noout -text
 
-docker compose up -d
+docker compose up -d --quiet-pull
 sleep 5
 
 docker compose exec backup backup
@@ -33,7 +33,7 @@ sleep 5
 
 expect_running_containers "3"
 
-docker run --rm -it \
+docker run --rm \
   -v minio_backup_data:/minio_data \
   alpine \
   ash -c 'tar -xvf /minio_data/backup/test.tar.gz -C /tmp && test -f /tmp/backup/app_data/offen.db'

test/cli/run.sh

@@ -13,7 +13,7 @@ docker volume create app_data
 # correctly. It is not supposed to hold any data.
 docker volume create empty_data
 
-docker run -d \
+docker run -d -q \
   --name minio \
   --network test_network \
   --env MINIO_ROOT_USER=test \
@@ -25,7 +25,7 @@ docker run -d \
 
 docker exec minio mkdir -p /data/backup
 
-docker run -d \
+docker run -d -q \
   --name offen \
   --network test_network \
   -v app_data:/var/opt/offen/ \
@@ -33,7 +33,7 @@ docker run -d \
 
 sleep 10
 
-docker run --rm \
+docker run --rm -q \
   --network test_network \
   -v app_data:/backup/app_data \
   -v empty_data:/backup/empty_data \
@@ -48,7 +48,7 @@ docker run --rm \
   --entrypoint backup \
   offen/docker-volume-backup:${TEST_VERSION:-canary}
 
-docker run --rm -it \
+docker run --rm -q \
   -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'
 

test/commands/docker-compose.yml

@@ -42,10 +42,9 @@ services:
       EXEC_LABEL: test
       EXEC_FORWARD_OUTPUT: "true"
     volumes:
-      - archive:/archive
+      - ./local:/archive
       - app_data:/backup/data:ro
       - /var/run/docker.sock:/var/run/docker.sock
 
 volumes:
   app_data:
-  archive:

test/commands/run.sh

@@ -6,11 +6,12 @@ cd $(dirname $0)
 . ../util.sh
 current_test=$(basename $(pwd))
 
-docker compose up -d
+mkdir -p ./local
+
+docker compose up -d --quiet-pull
 sleep 30 # mariadb likes to take a bit before responding
 
 docker compose exec backup backup
-sudo cp -r $(docker volume inspect --format='{{ .Mountpoint }}' commands_archive) ./local
 
 tar -xvf ./local/test.tar.gz
 if [ ! -f ./backup/data/dump.sql ]; then
@@ -34,6 +35,7 @@ sudo rm -rf ./local
 
 info "Running commands test in swarm mode next."
 
+mkdir -p ./local
 docker swarm init
 
 docker stack deploy --compose-file=docker-compose.yml test_stack
@@ -47,8 +49,6 @@ sleep 20
 
 docker exec $(docker ps -q -f name=backup) backup
 
-sudo cp -r $(docker volume inspect --format='{{ .Mountpoint }}' test_stack_archive) ./local
-
 tar -xvf ./local/test.tar.gz
 if [ ! -f ./backup/data/dump.sql ]; then
   fail "Could not find file written by pre command."

test/confd/run.sh

@@ -8,7 +8,7 @@ current_test=$(basename $(pwd))
 
 mkdir -p local
 
-docker compose up -d
+docker compose up -d --quiet-pull
 
 # sleep until a backup is guaranteed to have happened on the 1 minute schedule
 sleep 100

test/dropbox/.gitignore

@@ -0,0 +1 @@
+user_v2_ready.yaml

test/dropbox/docker-compose.yml

@@ -0,0 +1,57 @@
+version: '3'
+
+services:
+  openapi_mock:
+    image: muonsoft/openapi-mock:0.3.9
+    environment:
+      OPENAPI_MOCK_USE_EXAMPLES: if_present
+      OPENAPI_MOCK_SPECIFICATION_URL: '/etc/openapi/user_v2.yaml'
+    ports:
+      - 8080:8080
+    volumes:
+      - ./user_v2_ready.yaml:/etc/openapi/user_v2.yaml
+
+  oauth2_mock:
+    image: ghcr.io/navikt/mock-oauth2-server:1.0.0
+    ports:
+      - 8090:8090
+    environment:
+      PORT: 8090
+      JSON_CONFIG_PATH: '/etc/oauth2/config.json'
+    volumes:
+      - ./oauth2_config.json:/etc/oauth2/config.json
+
+  backup:
+    image: offen/docker-volume-backup:${TEST_VERSION:-canary}
+    hostname: hostnametoken
+    depends_on:
+      - openapi_mock
+      - oauth2_mock
+    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
+      DROPBOX_ENDPOINT: http://openapi_mock:8080
+      DROPBOX_OAUTH2_ENDPOINT: http://oauth2_mock:8090
+      DROPBOX_REFRESH_TOKEN: test
+      DROPBOX_APP_KEY: test
+      DROPBOX_APP_SECRET: test
+      DROPBOX_REMOTE_PATH: /test
+      DROPBOX_CONCURRENCY_LEVEL: 6
+    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:
+  app_data:

test/dropbox/oauth2_config.json

@@ -0,0 +1,37 @@
+{
+   "interactiveLogin": true,
+   "httpServer": "NettyWrapper",
+   "tokenCallbacks": [
+       {
+           "issuerId": "issuer1",
+           "tokenExpiry": 120,
+           "requestMappings": [
+               {
+                   "requestParam": "scope",
+                   "match": "scope1",
+                   "claims": {
+                       "sub": "subByScope",
+                       "aud": [
+                           "audByScope"
+                       ]
+                   }
+               }
+           ]
+       },
+       {
+           "issuerId": "issuer2",
+           "requestMappings": [
+               {
+                   "requestParam": "someparam",
+                   "match": "somevalue",
+                   "claims": {
+                       "sub": "subBySomeParam",
+                       "aud": [
+                           "audBySomeParam"
+                       ]
+                   }
+               }
+           ]
+       }
+   ]
+}

test/dropbox/run.sh

@@ -0,0 +1,65 @@
+#!/bin/sh
+
+set -e
+
+cd "$(dirname "$0")"
+. ../util.sh
+current_test=$(basename $(pwd))
+
+cp user_v2.yaml user_v2_ready.yaml
+sudo sed -i 's/SERVER_MODIFIED_1/'"$(date "+%Y-%m-%dT%H:%M:%SZ")/g" user_v2_ready.yaml
+sudo sed -i 's/SERVER_MODIFIED_2/'"$(date "+%Y-%m-%dT%H:%M:%SZ" -d "14 days ago")/g" user_v2_ready.yaml
+
+docker compose up -d --quiet-pull
+sleep 5
+
+logs=$(docker compose exec -T backup backup)
+
+sleep 5
+
+expect_running_containers "4"
+
+echo "$logs"
+if echo "$logs" | grep -q "ERROR"; then
+  fail "Backup failed, errors reported: $logs"
+else
+  pass "Backup succeeded, no errors reported."
+fi
+
+# The second part of this test checks if backups get deleted when the retention
+# is set to 0 days (which it should not as it would mean all backups get deleted)
+BACKUP_RETENTION_DAYS="0" docker compose up -d
+sleep 5
+
+logs=$(docker compose exec -T backup backup)
+
+echo "$logs"
+if echo "$logs" | grep -q "Refusing to do so, please check your configuration"; then
+  pass "Remote backups have not been deleted."
+else
+  fail "Remote backups would have been deleted: $logs"
+fi
+
+# The third part of this test checks if old backups get deleted when the retention
+# is set to 7 days (which it should)
+
+BACKUP_RETENTION_DAYS="7" docker compose up -d
+sleep 5
+
+info "Create second backup and prune"
+logs=$(docker compose exec -T backup backup)
+
+echo "$logs"
+if echo "$logs" | grep -q "Pruned 1 out of 2 backups as their age exceeded the configured retention period"; then
+  pass "Old remote backup has been pruned, new one is still present."
+elif echo "$logs" | grep -q "ERROR"; then
+  fail "Pruning failed, errors reported: $logs"
+elif echo "$logs" | grep -q "None of 1 existing backups were pruned"; then
+  fail "Pruning failed, old backup has not been pruned: $logs"
+else
+  fail "Pruning failed, unknown result: $logs"
+fi
+
+
+docker compose down --volumes
+rm user_v2_ready.yaml

test/extend/run.sh

@@ -8,11 +8,12 @@ current_test=$(basename $(pwd))
 
 mkdir -p local
 
+export BASE_VERSION="${TEST_VERSION:-canary}"
 export TEST_VERSION="${TEST_VERSION:-canary}-with-rsync"
 
-docker build . -t offen/docker-volume-backup:$TEST_VERSION
+docker build . -t offen/docker-volume-backup:$TEST_VERSION --build-arg version=$BASE_VERSION
 
-docker compose up -d
+docker compose up -d --quiet-pull
 sleep 5
 
 docker compose exec backup backup

test/gpg/run.sh

@@ -8,7 +8,7 @@ current_test=$(basename $(pwd))
 
 mkdir -p local
 
-docker compose up -d
+docker compose up -d --quiet-pull
 sleep 5
 
 docker compose exec backup backup

test/ignore/run.sh

@@ -8,7 +8,7 @@ current_test=$(basename $(pwd))
 
 mkdir -p local
 
-docker compose up -d
+docker compose up -d --quiet-pull
 sleep 5
 docker compose exec backup backup
 

test/local/run.sh

@@ -8,7 +8,7 @@ current_test=$(basename $(pwd))
 
 mkdir -p local
 
-docker compose up -d
+docker compose up -d --quiet-pull
 sleep 5
 
 # A symlink for a known file in the volume is created so the test can check
@@ -41,7 +41,6 @@ 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
 
@@ -52,4 +51,23 @@ if [ "$(find ./local -type f | wc -l)" != "1" ]; then
 fi
 pass "Local backups have not been deleted."
 
+# The third part of this test checks if old backups get deleted when the retention
+# is set to 7 days (which it should)
+
+BACKUP_RETENTION_DAYS="7" docker compose up -d
+sleep 5
+
+info "Create first backup with no prune"
+docker compose exec backup backup
+
+touch -r ./local/test-hostnametoken.tar.gz -d "14 days ago" ./local/test-hostnametoken-old.tar.gz
+
+info "Create second backup and prune"
+docker compose exec backup backup
+
+test ! -f ./local/test-hostnametoken-old.tar.gz
+test -f ./local/test-hostnametoken.tar.gz
+
+pass "Old remote backup has been pruned, new one is still present."
+
 docker compose down --volumes

test/notifications/run.sh

@@ -8,7 +8,7 @@ current_test=$(basename $(pwd))
 
 mkdir -p local
 
-docker compose up -d
+docker compose up -d --quiet-pull
 sleep 5
 
 GOTIFY_TOKEN=$(curl -sSLX POST -H 'Content-Type: application/json' -d '{"name":"test"}' http://admin:custom@localhost:8080/application | jq -r '.token')

test/ownership/run.sh

@@ -9,7 +9,7 @@ current_test=$(basename $(pwd))
 
 mkdir -p local
 
-docker compose up -d
+docker compose up -d --quiet-pull
 sleep 5
 
 docker compose exec backup backup

test/pruning/docker-compose.yml

@@ -0,0 +1,50 @@
+version: '3'
+
+services:
+  minio:
+    image: minio/minio:RELEASE.2020-08-04T23-10-51Z
+    environment:
+      MINIO_ROOT_USER: test
+      MINIO_ROOT_PASSWORD: test
+      MINIO_ACCESS_KEY: test
+      MINIO_SECRET_KEY: GMusLtUmILge2by+z890kQ
+    entrypoint: /bin/ash -c 'mkdir -p /data/backup && minio server /data'
+    volumes:
+      - minio_backup_data:/data
+
+  backup:
+    image: offen/docker-volume-backup:${TEST_VERSION:-canary}
+    hostname: hostnametoken
+    depends_on:
+      - minio
+    restart: always
+    environment:
+      AWS_ACCESS_KEY_ID: test
+      AWS_SECRET_ACCESS_KEY: GMusLtUmILge2by+z890kQ
+      AWS_ENDPOINT: minio:9000
+      AWS_ENDPOINT_PROTO: http
+      AWS_S3_BUCKET_NAME: backup
+      BACKUP_FILENAME_EXPAND: 'true'
+      BACKUP_FILENAME: test-$$HOSTNAME.tar.gz
+      BACKUP_CRON_EXPRESSION: 0 0 5 31 2 ?
+      BACKUP_RETENTION_DAYS: 7
+      BACKUP_PRUNING_LEEWAY: 5s
+      BACKUP_PRUNING_PREFIX: test
+      BACKUP_LATEST_SYMLINK: test-$$HOSTNAME.latest.tar.gz
+      BACKUP_SKIP_BACKENDS_FROM_PRUNE: 's3'
+    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:
+  minio_backup_data:
+    name: minio_backup_data

test/pruning/run.sh

@@ -0,0 +1,70 @@
+#!/bin/sh
+
+# Tests prune-skipping with multiple backends (local, s3)
+# Pruning itself is tested individually for each storage backend
+
+set -e
+
+cd "$(dirname "$0")"
+. ../util.sh
+current_test=$(basename $(pwd))
+
+mkdir -p local
+
+docker compose up -d --quiet-pull
+sleep 5
+
+docker compose exec backup backup
+
+sleep 5
+
+expect_running_containers "3"
+
+touch -r ./local/test-hostnametoken.tar.gz -d "14 days ago" ./local/test-hostnametoken-old.tar.gz
+
+docker run --rm \
+  -v minio_backup_data:/minio_data \
+  alpine \
+  ash -c 'touch -d@$(( $(date +%s) - 1209600 )) /minio_data/backup/test-hostnametoken-old.tar.gz'
+
+# Skip s3 backend from prune
+
+docker compose up -d
+sleep 5
+
+info "Create backup with no prune for s3 backend"
+docker compose exec backup backup
+
+info "Check if old backup has been pruned (local)"
+test ! -f ./local/test-hostnametoken-old.tar.gz
+
+info "Check if old backup has NOT been pruned (s3)"
+docker run --rm \
+  -v minio_backup_data:/minio_data \
+  alpine \
+  ash -c 'test -f /minio_data/backup/test-hostnametoken-old.tar.gz'
+
+pass "Old remote backup has been pruned locally, skipped S3 backend is untouched."
+
+# Skip local and s3 backend from prune (all backends)
+
+touch -r ./local/test-hostnametoken.tar.gz -d "14 days ago" ./local/test-hostnametoken-old.tar.gz
+
+docker compose up -d
+sleep 5
+
+info "Create backup with no prune for both backends"
+docker compose exec -e BACKUP_SKIP_BACKENDS_FROM_PRUNE="s3,local" backup backup
+
+info "Check if old backup has NOT been pruned (local)"
+test -f ./local/test-hostnametoken-old.tar.gz
+
+info "Check if old backup has NOT been pruned (s3)"
+docker run --rm \
+  -v minio_backup_data:/minio_data \
+  alpine \
+  ash -c 'test -f /minio_data/backup/test-hostnametoken-old.tar.gz'
+
+pass "Skipped all backends while pruning."
+
+docker compose down --volumes

test/s3/run.sh

@@ -6,18 +6,16 @@ cd "$(dirname "$0")"
 . ../util.sh
 current_test=$(basename $(pwd))
 
-docker compose up -d
+docker compose up -d --quiet-pull
 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 \
+docker run --rm \
   -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'
@@ -26,17 +24,40 @@ 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 \
+docker run --rm \
   -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."
 
+# The third part of this test checks if old backups get deleted when the retention
+# is set to 7 days (which it should)
+
+BACKUP_RETENTION_DAYS="7" docker compose up -d
+sleep 5
+
+info "Create first backup with no prune"
+docker compose exec backup backup
+
+docker run --rm \
+  -v minio_backup_data:/minio_data \
+  alpine \
+  ash -c 'touch -d@$(( $(date +%s) - 1209600 )) /minio_data/backup/test-hostnametoken-old.tar.gz'
+
+info "Create second backup and prune"
+docker compose exec backup backup
+
+docker run --rm \
+  -v minio_backup_data:/minio_data \
+  alpine \
+  ash -c 'test ! -f /minio_data/backup/test-hostnametoken-old.tar.gz && test -f /minio_data/backup/test-hostnametoken.tar.gz'
+
+pass "Old remote backup has been pruned, new one is still present."
+
 docker compose down --volumes

test/secrets/run.sh

@@ -22,7 +22,7 @@ sleep 20
 
 docker exec $(docker ps -q -f name=backup) backup
 
-docker run --rm -it \
+docker run --rm \
   -v backup_data:/data alpine \
   ash -c 'tar -xf /data/backup/test.tar.gz && test -f /backup/pg_data/PG_VERSION'
 
@@ -31,6 +31,16 @@ pass "Found relevant files in untared backup."
 sleep 5
 expect_running_containers "5"
 
+docker exec -e AWS_ACCESS_KEY_ID=test $(docker ps -q -f name=backup) backup \
+  && fail "Backup should have failed due to duplicate env variables."
+
+pass "Backup failed due to duplicate env variables."
+
+docker exec -e AWS_ACCESS_KEY_ID_FILE=/tmp/nonexistant $(docker ps -q -f name=backup) backup \
+  && fail "Backup should have failed due to non existing file env variable."
+
+pass "Backup failed due to non existing file env variable."
+
 docker stack rm test_stack
 
 docker secret rm minio_root_password

test/ssh/run.sh

@@ -8,7 +8,7 @@ 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
+docker compose up -d --quiet-pull
 sleep 5
 
 docker compose exec backup backup
@@ -17,7 +17,7 @@ sleep 5
 
 expect_running_containers 3
 
-docker run --rm -it \
+docker run --rm \
   -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'
@@ -26,18 +26,43 @@ 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 \
+docker run --rm \
   -v ssh_backup_data:/ssh_data \
   alpine \
   ash -c '[ $(find /ssh_data/ -type f | wc -l) = "1" ]'
 
 pass "Remote backups have not been deleted."
 
+# The third part of this test checks if old backups get deleted when the retention
+# is set to 7 days (which it should)
+
+BACKUP_RETENTION_DAYS="7" docker compose up -d
+sleep 5
+
+info "Create first backup with no prune"
+docker compose exec backup backup
+
+# Set the modification date of the old backup to 14 days ago
+docker run --rm \
+  -v ssh_backup_data:/ssh_data \
+  --user 1000 \
+  alpine \
+  ash -c 'touch -d@$(( $(date +%s) - 1209600 )) /ssh_data/test-hostnametoken-old.tar.gz'
+
+info "Create second backup and prune"
+docker compose exec backup backup
+
+docker run --rm \
+  -v ssh_backup_data:/ssh_data \
+  alpine \
+  ash -c 'test ! -f /ssh_data/test-hostnametoken-old.tar.gz && test -f /ssh_data/test-hostnametoken.tar.gz'
+
+pass "Old remote backup has been pruned, new one is still present."
+
 docker compose down --volumes
 rm -f id_rsa id_rsa.pub

test/swarm/run.sh

@@ -19,7 +19,7 @@ sleep 20
 
 docker exec $(docker ps -q -f name=backup) backup
 
-docker run --rm -it \
+docker run --rm \
   -v backup_data:/data alpine \
   ash -c 'tar -xf /data/backup/test.tar.gz && test -f /backup/pg_data/PG_VERSION'
 
@@ -29,6 +29,7 @@ sleep 5
 expect_running_containers "5"
 
 docker stack rm test_stack
+sleep 1
 docker swarm leave --force
 
 sleep 10

test/user/.gitignore

@@ -0,0 +1,2 @@
+local
+backup

test/user/docker-compose.yml

@@ -0,0 +1,30 @@
+version: '2.4'
+
+services:
+  alpine:
+    image: alpine:3.17.3
+    tty: true 
+    volumes:
+      - app_data:/tmp
+    labels:
+      - docker-volume-backup.archive-pre.user=testuser
+      - docker-volume-backup.archive-pre=/bin/sh -c 'whoami > /tmp/whoami.txt'
+
+
+  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 ?
+      EXEC_FORWARD_OUTPUT: "true"
+    volumes:
+      - ./local:/archive
+      - app_data:/backup/data:ro
+      - /var/run/docker.sock:/var/run/docker.sock
+
+volumes:
+  app_data:
+  archive:

test/user/run.sh

@@ -0,0 +1,30 @@
+#!/bin/sh
+
+set -e
+
+cd $(dirname $0)
+. ../util.sh
+current_test=$(basename $(pwd))
+
+docker compose up -d --quiet-pull
+
+user_name=testuser
+docker exec user-alpine-1 adduser --disabled-password "$user_name"
+
+docker compose exec backup backup
+
+tar -xvf ./local/test.tar.gz
+if [ ! -f ./backup/data/whoami.txt ]; then
+  fail "Could not find file written by pre command."
+fi
+pass "Found expected file."
+
+tar -xvf ./local/test.tar.gz
+if [ "$(cat ./backup/data/whoami.txt)" != "$user_name" ]; then
+  fail "Could not find expected user name."
+fi
+pass "Found expected user."
+
+docker compose down --volumes
+sudo rm -rf ./local
+

test/webdav/run.sh

@@ -6,7 +6,7 @@ cd "$(dirname "$0")"
 . ../util.sh
 current_test=$(basename $(pwd))
 
-docker compose up -d
+docker compose up -d --quiet-pull
 sleep 5
 
 docker compose exec backup backup
@@ -15,7 +15,7 @@ sleep 5
 
 expect_running_containers "3"
 
-docker run --rm -it \
+docker run --rm \
   -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'
@@ -24,17 +24,42 @@ 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 \
+docker run --rm \
   -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."
 
+# The third part of this test checks if old backups get deleted when the retention
+# is set to 7 days (which it should)
+
+BACKUP_RETENTION_DAYS="7" docker compose up -d
+sleep 5
+
+info "Create first backup with no prune"
+docker compose exec backup backup
+
+# Set the modification date of the old backup to 14 days ago
+docker run --rm \
+  -v webdav_backup_data:/webdav_data \
+  --user 82 \
+  alpine \
+  ash -c 'touch -d@$(( $(date +%s) - 1209600 )) /webdav_data/data/my/new/path/test-hostnametoken-old.tar.gz'
+
+info "Create second backup and prune"
+docker compose exec backup backup
+
+docker run --rm \
+  -v webdav_backup_data:/webdav_data \
+  alpine \
+  ash -c 'test ! -f /webdav_data/data/my/new/path/test-hostnametoken-old.tar.gz && test -f /webdav_data/data/my/new/path/test-hostnametoken.tar.gz'
+
+pass "Old remote backup has been pruned, new one is still present."
+
 docker compose down --volumes

test/zstd/run.sh

@@ -0,0 +1,46 @@
+#!/bin/sh
+
+set -e
+
+cd $(dirname $0)
+. ../util.sh
+current_test=$(basename $(pwd))
+
+docker network create test_network
+docker volume create app_data
+
+mkdir -p local
+
+docker run -d -q \
+  --name offen \
+  --network test_network \
+  -v app_data:/var/opt/offen/ \
+  offen/offen:latest
+
+sleep 10
+
+docker run --rm -q \
+  --network test_network \
+  -v app_data:/backup/app_data \
+  -v ./local:/archive \
+  -v /var/run/docker.sock:/var/run/docker.sock \
+  --env BACKUP_COMPRESSION=zst \
+  --env BACKUP_FILENAME='test.{{ .Extension }}' \
+  --entrypoint backup \
+  offen/docker-volume-backup:${TEST_VERSION:-canary}
+
+tmp_dir=$(mktemp -d)
+tar -xvf ./local/test.tar.zst --zstd -C $tmp_dir
+if [ ! -f "$tmp_dir/backup/app_data/offen.db" ]; then
+  fail "Could not find expected file in untared archive."
+fi
+pass "Found relevant files in untared local backup."
+
+# This test does not stop containers during backup. This is happening on
+# purpose in order to cover this setup as well.
+expect_running_containers "1"
+
+docker rm $(docker stop offen)
+
+docker volume rm app_data
+docker network rm test_network