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.
Dropbox was missing from notification docs
2025-12-05 17:18:02 +01:00 · 2023-08-30 20:14:24 +02:00 · 2023-08-28 20:42:45 +02:00 · 2023-08-27 19:19:11 +02:00 · 2023-08-27 18:14:55 +02:00 · 2023-08-25 12:44:43 +02:00
44 changed files with 13857 additions and 214 deletions
--- a/.github/workflows/golangci-lint.yml
+++ b/.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"
--- a/.golangci.yml
+++ b/.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
--- a/README.md
+++ b/README.md
@@ -4,10 +4,10 @@

 # 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 -->

@@ -36,6 +36,7 @@ It handles __recurring or one-off backups of Docker volumes__ to a __local direc
  - [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)
@@ -44,6 +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)
@@ -137,6 +139,9 @@ Documentation references Docker Hub, but all examples will work using ghcr.io ju
 ## 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
@@ -203,6 +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
@@ -222,14 +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
@@ -356,6 +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`
@@ -1020,6 +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.
@@ -1187,6 +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
--- a/cmd/backup/config.go
+++ b/cmd/backup/config.go
@@ -7,9 +7,9 @@ import (
 	"crypto/x509"
 	"encoding/pem"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"regexp"
+	"strconv"
 	"time"
 )

@@ -24,9 +24,7 @@ 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"`
@@ -41,6 +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"`
@@ -70,17 +69,13 @@ 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/"`
-}
-
-func (c *Config) resolveSecret(envVar string, secretPath string) (string, error) {
-	if secretPath == "" {
-		return envVar, nil
-	}
-	data, err := os.ReadFile(secretPath)
-	if err != nil {
-		return "", fmt.Errorf("resolveSecret: error reading secret path: %w", err)
-	}
-	return string(data), nil
+	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"`
 }

 type CompressionType string
@@ -107,7 +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)
 	}
@@ -135,3 +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)
+}
--- a/cmd/backup/exec.go
+++ b/cmd/backup/exec.go
@@ -10,7 +10,7 @@ import (
 	"bytes"
 	"context"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"os"
 	"strings"

@@ -51,19 +51,15 @@ func (s *script) exec(containerRef string, command string, user string) ([]byte,
 		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)
 	}
@@ -152,9 +148,9 @@ 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"]
 			}

 			userLabelName := fmt.Sprintf("%s.user", label)
--- a/cmd/backup/lock.go
+++ b/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)
--- a/cmd/backup/main.go
+++ b/cmd/backup/main.go
@@ -15,7 +15,7 @@ func main() {
 	}

 	unlock, err := s.lock("/var/lock/dockervolumebackup.lock")
-	defer unlock()
+	defer s.must(unlock())
 	s.must(err)

 	defer func() {
@@ -34,7 +34,6 @@ func main() {
 		if err := s.runHooks(nil); err != nil {
 			s.logger.Error(
 				fmt.Sprintf(
-
 					"Backup procedure ran successfully, but an error ocurred calling the registered hooks: %v",
 					err,
 				),
--- a/cmd/backup/script.go
+++ b/cmd/backup/script.go
@@ -14,16 +14,20 @@ import (
 	"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/ProtonMail/go-crypto/openpgp"
 	"github.com/containrrr/shoutrrr"
 	"github.com/containrrr/shoutrrr/pkg/router"
 	"github.com/docker/docker/api/types"
@@ -31,10 +35,9 @@ import (
 	"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"
-	"golang.org/x/crypto/openpgp"
 	"golang.org/x/sync/errgroup"
 )

@@ -75,6 +78,7 @@ func newScript() (*script, error) {
 				"SSH":     {},
 				"Local":   {},
 				"Azure":   {},
+				"Dropbox": {},
 			},
 		},
 	}
@@ -85,6 +89,28 @@ 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)
 	}
@@ -124,28 +150,19 @@ func newScript() (*script, error) {
 	logFunc := func(logType storage.LogLevel, context string, msg string, params ...any) {
 		switch logType {
 		case storage.LogLevelWarning:
-			s.logger.Warn(fmt.Sprintf("["+context+"] "+msg, params...))
+			s.logger.Warn(fmt.Sprintf(msg, params...), "storage", context)
 		case storage.LogLevelError:
-			s.logger.Error(fmt.Sprintf("["+context+"] "+msg, params...))
-		case storage.LogLevelInfo:
+			s.logger.Error(fmt.Sprintf(msg, params...), "storage", context)
 		default:
-			s.logger.Info(fmt.Sprintf("["+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,
@@ -156,7 +173,7 @@ func newScript() (*script, error) {
 			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)
 		}
@@ -171,7 +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)
 		}
@@ -188,7 +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)
 		}
@@ -213,11 +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",
@@ -573,6 +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
@@ -604,3 +644,14 @@ func (s *script) must(err error) {
 		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
+		},
+	)
+}
--- a/docs/NOTIFICATION-TEMPLATES.md
+++ b/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
--- a/go.mod
+++ b/go.mod
@@ -9,25 +9,35 @@ require (
 	github.com/cosiner/argv v0.1.0
 	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 v7.0.61
+	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 v0.11.0
+	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/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/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/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
@@ -52,9 +62,9 @@ require (
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/rs/xid v1.5.0 // indirect
 	github.com/sirupsen/logrus v1.9.3 // indirect
-	golang.org/x/net v0.12.0 // indirect
-	golang.org/x/sys v0.10.0 // indirect
-	golang.org/x/text v0.11.0 // 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
 	gotest.tools/v3 v3.0.3 // indirect
--- a/go.sum
+++ b/go.sum
@@ -201,6 +201,8 @@ github.com/DataDog/datadog-go v3.2.0+incompatible/go.mod h1:LButxg5PwREeZtORoXG3
 github.com/Microsoft/go-winio v0.5.2 h1:a9IhgEQBCUEk6QCdml9CiJGhAws+YwffDHEMp1VMrpA=
 github.com/Microsoft/go-winio v0.5.2/go.mod h1:WpS1mjBmmwHBEWmogvA2mj8546UReBk4v8QkMxJ6pZY=
 github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAElWljhcU=
+github.com/ProtonMail/go-crypto v0.0.0-20230717121422-5aa5874ade95 h1:KLq8BE0KwCL+mmXnjLWEAOYO+2l2AE4YMmqG1ZpZHBs=
+github.com/ProtonMail/go-crypto v0.0.0-20230717121422-5aa5874ade95/go.mod h1:EjAoLdwvbIOoOQr3ihjnSoLZRtE8azugULFRteWMNc0=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
@@ -218,6 +220,7 @@ github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
 github.com/bgentry/speakeasy v0.1.0/go.mod h1:+zsyZBPWlz7T6j88CTgSN5bM796AkVf0kBD4zp0CCIs=
+github.com/bwesterb/go-ristretto v1.2.3/go.mod h1:fUIoIZaG73pV5biE2Blr2xEzDoMj7NFEuV9ekS419A0=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
 github.com/cespare/xxhash v1.1.0/go.mod h1:XrSqR1VqqWfGrhpAt58auRo0WTKS1nRRg3ghfAqPWnc=
 github.com/cespare/xxhash/v2 v2.1.1/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
@@ -227,6 +230,8 @@ github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMn
 github.com/circonus-labs/circonus-gometrics v2.3.1+incompatible/go.mod h1:nmEj6Dob7S7YxXgwXpfOuvO54S+tGdZdw9fuRZt25Ag=
 github.com/circonus-labs/circonusllhist v0.1.3/go.mod h1:kMXHVDlOchFAehlya5ePtbp5jckzBHf4XRpQvBOLI+I=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
+github.com/cloudflare/circl v1.3.3 h1:fE/Qz0QdIGqeWfnwq0RE0R7MI51s0M2E4Ga9kq5AEMs=
+github.com/cloudflare/circl v1.3.3/go.mod h1:5XYMA4rFBvNIrhs50XuiBJ15vF2pZn4nnUKZrLbUZFA=
 github.com/cncf/udpa/go v0.0.0-20191209042840-269d4d468f6f/go.mod h1:M8M6+tZqaGXZJjfX53e64911xZQV5JYwmTeXPW+k8Sc=
 github.com/cncf/udpa/go v0.0.0-20200629203442-efcf912fb354/go.mod h1:WmhPx2Nbnhtbo57+VJT5O0JRkEi1Wbu0z5j0R8u5Hbk=
 github.com/cncf/udpa/go v0.0.0-20201120205902-5459f2c99403/go.mod h1:WmhPx2Nbnhtbo57+VJT5O0JRkEi1Wbu0z5j0R8u5Hbk=
@@ -257,6 +262,8 @@ github.com/docker/go-connections v0.4.0 h1:El9xVISelRB7BuFusrZozjnkIM5YnzCViNKoh
 github.com/docker/go-connections v0.4.0/go.mod h1:Gbd7IOopHjR8Iph03tsViu4nIes5XhDvyHbTtUxmeec=
 github.com/docker/go-units v0.4.0 h1:3uh0PgVws3nIA0Q+MwDC8yjEPf9zjRfZZWXZYDct3Tw=
 github.com/docker/go-units v0.4.0/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
+github.com/dropbox/dropbox-sdk-go-unofficial/v6 v6.0.5 h1:FT+t0UEDykcor4y3dMVKXIiWJETBpRgERYTGlmMd7HU=
+github.com/dropbox/dropbox-sdk-go-unofficial/v6 v6.0.5/go.mod h1:rSS3kM9XMzSQ6pw91Qgd6yB5jdt70N4OdtrAf74As5M=
 github.com/dustin/go-humanize v1.0.0/go.mod h1:HtrtbFcZ19U5GC7JDqmcUSB87Iq5E25KnS6fMYU6eOk=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
 github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
@@ -444,8 +451,6 @@ github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1
 github.com/jstemmer/go-junit-report v0.9.1/go.mod h1:Brl9GWCQeLvo8nXZwPNNblvFj/XSXhF0NWZEnDohbsk=
 github.com/julienschmidt/httprouter v1.2.0/go.mod h1:SYymIcj16QtmaHHD7aYtjjsJG7VTCxuUUipMqKk8s4w=
 github.com/julienschmidt/httprouter v1.3.0/go.mod h1:JR6WtHb+2LUe8TCKY3cZOxFyyO8IZAc4RVcycCCAKdM=
-github.com/kelseyhightower/envconfig v1.4.0 h1:Im6hONhd3pLkfDFsbRgu68RDNkGF1r3dvMUtDTo2cv8=
-github.com/kelseyhightower/envconfig v1.4.0/go.mod h1:cccZRl6mQpaq41TPp5QxidR+Sa3axMbJDNb//FQX6Gg=
 github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/klauspost/compress v1.16.7 h1:2mk3MPGNzKyxErAw8YaohYh69+pa4sIQSC0fPGCFR9I=
@@ -492,8 +497,8 @@ github.com/miekg/dns v1.1.26/go.mod h1:bPDLeHnStXmXAq1m/Ch/hvfNHr14JKNPMBo3VZKju
 github.com/miekg/dns v1.1.41/go.mod h1:p6aan82bvRIyn+zDIv9xYNUpwa73JcSh9BKwknJysuI=
 github.com/minio/md5-simd v1.1.2 h1:Gdi1DZK69+ZVMoNHRXJyNcxrMA4dSxoYHZSQbirFg34=
 github.com/minio/md5-simd v1.1.2/go.mod h1:MzdKDxYpY2BT9XQFocsiZf/NKVtR7nkE4RoEpN+20RM=
-github.com/minio/minio-go/v7 v7.0.61 h1:87c+x8J3jxQ5VUGimV9oHdpjsAvy3fhneEBKuoKEVUI=
-github.com/minio/minio-go/v7 v7.0.61/go.mod h1:BTu8FcrEw+HidY0zd/0eny43QnVNkXRPXrLXFuQBHXg=
+github.com/minio/minio-go/v7 v7.0.62 h1:qNYsFZHEzl+NfH8UxW4jpmlKav1qUAgfY30YNRneVhc=
+github.com/minio/minio-go/v7 v7.0.62/go.mod h1:Q6X7Qjb7WMhvG65qKf4gUgA5XaiSox74kR1uAEjxRS4=
 github.com/minio/sha256-simd v1.0.1 h1:6kaan5IFmwTNynnKKpDHe6FWHohJOHhCPchzK49dzMM=
 github.com/minio/sha256-simd v1.0.1/go.mod h1:Pz6AKMiUdngCLpeTL/RJY1M9rUuPMYujV5xJjtbRSN8=
 github.com/mitchellh/cli v1.0.0/go.mod h1:hNIlj7HEI86fIcpObd7a0FcrxTWetlwJDGcceTlRvqc=
@@ -520,6 +525,8 @@ github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e h1:fD57ERR4JtEqsWb
 github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e/go.mod h1:zD1mROLANZcx1PVRCS0qkT7pwLkGfwJo4zjcN/Tysno=
 github.com/nxadm/tail v1.4.4/go.mod h1:kenIhsEOeOJmVchQTgglprH7qJGnHDVpk1VPCcaMI8A=
 github.com/nxadm/tail v1.4.8/go.mod h1:+ncqLTQzXmGhMZNUePPaPqPvBxHAIsmXswZKocGu+AU=
+github.com/offen/envconfig v1.5.0 h1:LHL4wYIDVeoGxSDI40MShmWfss3gYUlCdstfSiSq4Fk=
+github.com/offen/envconfig v1.5.0/go.mod h1:L7ny7R+4JWH3VVnZ+ARHvZysWUiZ2eQcm3L0imU9ACY=
 github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
 github.com/onsi/ginkgo v1.12.1/go.mod h1:zj2OWP4+oCPe1qIXoGWkgMRwljMUYCdkwsT2108oapk=
 github.com/onsi/ginkgo v1.16.4 h1:29JGrr5oVBm5ulCWet69zQkzWipVXIol6ygQUe/EzNc=
@@ -662,8 +669,10 @@ golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5y
 golang.org/x/crypto v0.0.0-20211108221036-ceb1ce70b4fa/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
 golang.org/x/crypto v0.0.0-20220525230936-793ad666bf5e/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 golang.org/x/crypto v0.1.0/go.mod h1:RecgLatLF4+eUMCP1PoPZQb+cVrJcOPbHkTkbkB9sbw=
-golang.org/x/crypto v0.11.0 h1:6Ewdq3tDic1mg5xRO4milcWCfMVQhI4NkqWWvqejpuA=
-golang.org/x/crypto v0.11.0/go.mod h1:xgJhtzW8F9jGdVFWZESrid1U1bjeNy4zgy5cRr/CIio=
+golang.org/x/crypto v0.3.1-0.20221117191849-2c476679df9a/go.mod h1:hebNnKkNXi2UzZN1eVRvBB7co0a+JxK6XbPiWVs/3J4=
+golang.org/x/crypto v0.7.0/go.mod h1:pYwdfH91IfpZVANVyUOhSIPZaFoJGxTFbZhFTx+dXZU=
+golang.org/x/crypto v0.12.0 h1:tFM/ta59kqch6LlvYnPa0yx5a83cL2nHflFhYKvv9Yk=
+golang.org/x/crypto v0.12.0/go.mod h1:NF0Gs7EO5K4qLn+Ylc+fih8BSTeIjAP05siRnAh98yw=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190510132918-efd6b22b2522/go.mod h1:ZjyILWgesfNpC6sMxTJOJm9Kp84zZh5NQWvqDGG3Qr8=
@@ -702,6 +711,7 @@ golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.6.0-dev.0.20220106191415-9b9b3d81d5e3/go.mod h1:3p9vT2HGsQu2K1YbXdKPJLVgG5VJdoTa1poYQBtP1AY=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/mod v0.6.0/go.mod h1:4mET923SAdbXp2ki8ey+zGs1SLqsuM2Y0uvdZR/fUNI=
+golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -760,8 +770,11 @@ golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug
 golang.org/x/net v0.0.0-20220909164309-bea034e7d591/go.mod h1:YDH+HFinaLZZlnHAfSS6ZXJJ9M9t4Dl22yv3iI2vPwk=
 golang.org/x/net v0.0.0-20221014081412-f15817d10f9b/go.mod h1:YDH+HFinaLZZlnHAfSS6ZXJJ9M9t4Dl22yv3iI2vPwk=
 golang.org/x/net v0.1.0/go.mod h1:Cx3nUiGt4eDBEyega/BKRp+/AlGL8hYe7U9odMt2Cco=
-golang.org/x/net v0.12.0 h1:cfawfvKITfUsFCeJIHJrbSxpeu/E81khclypR0GVT50=
-golang.org/x/net v0.12.0/go.mod h1:zEVYFnQC7m/vmpQFELhcD1EWkZlX69l4oqgmer6hfKA=
+golang.org/x/net v0.2.0/go.mod h1:KqCZLdyyvdV855qA2rE3GC2aiw5xGR5TEjj8smXukLY=
+golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
+golang.org/x/net v0.8.0/go.mod h1:QVkue5JL9kW//ek3r6jTKnTFis1tRmNAW2P1shuFdJc=
+golang.org/x/net v0.14.0 h1:BONx9s002vGdD9umnlX1Po8vOZmrgH34qlHcD1MfK14=
+golang.org/x/net v0.14.0/go.mod h1:PpSgVXXLK0OxS0F31C1/tv6XNguvCrnXIDrFMspZIUI=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
@@ -785,6 +798,7 @@ golang.org/x/oauth2 v0.0.0-20220608161450-d0670ef3b1eb/go.mod h1:jaDAt6Dkxork7Lm
 golang.org/x/oauth2 v0.0.0-20220622183110-fd043fe589d2/go.mod h1:jaDAt6Dkxork7LmZnYtzbRWj0W47D86a3TGe0YHBvmE=
 golang.org/x/oauth2 v0.0.0-20220822191816-0ebed06d0094/go.mod h1:h4gKUeWbJ4rQPri7E0u6Gs4e9Ri2zaLxzw5DI5XGrYg=
 golang.org/x/oauth2 v0.0.0-20220909003341-f21342109be1/go.mod h1:h4gKUeWbJ4rQPri7E0u6Gs4e9Ri2zaLxzw5DI5XGrYg=
+golang.org/x/oauth2 v0.0.0-20221014153046-6fdb5e3db783 h1:nt+Q6cXKz4MosCSpnbMtqiQ8Oz0pxTef2B4Vca2lvfk=
 golang.org/x/oauth2 v0.0.0-20221014153046-6fdb5e3db783/go.mod h1:h4gKUeWbJ4rQPri7E0u6Gs4e9Ri2zaLxzw5DI5XGrYg=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -898,14 +912,20 @@ golang.org/x/sys v0.0.0-20220728004956-3c1f35247d10/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220908164124-27713097b956/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.1.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.2.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.3.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.10.0 h1:SqMFp9UcQJZa+pmYuAKjd9xq1f0j5rLcDIk0mj4qAsA=
-golang.org/x/sys v0.10.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.11.0 h1:eG7RXZHdqOJ1i+0lgLgCpSXAp6M3LYlAo6osgSi0xOM=
+golang.org/x/sys v0.11.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/term v0.1.0/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
-golang.org/x/term v0.10.0 h1:3R7pNqamzBraeqj/Tj8qt1aQ2HpmlC+Cx/qL/7hn4/c=
-golang.org/x/term v0.10.0/go.mod h1:lpqdcUyK/oCiQxvxVrppt5ggO2KCZ5QblwqPnfZ6d5o=
+golang.org/x/term v0.2.0/go.mod h1:TVmDHMZPmdnySmBfhjOoOdhjzdE1h4u1VwSiw2l1Nuc=
+golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k=
+golang.org/x/term v0.6.0/go.mod h1:m6U89DPEgQRMq3DNkDClhWw02AUbt2daBVO4cn4Hv9U=
+golang.org/x/term v0.11.0 h1:F9tnn/DA/Im8nCwm+fX+1/eBwi4qFjRT++MhtVC4ZX0=
+golang.org/x/term v0.11.0/go.mod h1:zC9APTIj3jG3FdV/Ons+XE1riIZXG4aZ4GTHiPZJPIU=
 golang.org/x/text v0.0.0-20170915032832-14c0d48ead0c/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
@@ -916,8 +936,10 @@ golang.org/x/text v0.3.5/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/text v0.4.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
-golang.org/x/text v0.11.0 h1:LAntKIrcmeSKERyiOh0XMV39LXS8IE9UL2yP7+f5ij4=
-golang.org/x/text v0.11.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
+golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
+golang.org/x/text v0.8.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
+golang.org/x/text v0.12.0 h1:k+n5B8goJNdU7hSvEtMUz3d1Q6D/XW4COJSJR6fN0mc=
+golang.org/x/text v0.12.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
 golang.org/x/time v0.0.0-20181108054448-85acf8d2951c/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20190308202827-9d24e82272b4/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20191024005414-555d28b269f0/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
@@ -983,6 +1005,7 @@ golang.org/x/tools v0.1.5/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk=
 golang.org/x/tools v0.1.10/go.mod h1:Uh6Zz+xoGYZom868N8YTex3t7RhtHDBrE8Gzo9bV56E=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
 golang.org/x/tools v0.2.0/go.mod h1:y4OqIKeOV/fWJetJ8bXPU1sEVniLMIyDAZWeHdV+NTA=
+golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
@@ -1046,6 +1069,7 @@ google.golang.org/appengine v1.5.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7
 google.golang.org/appengine v1.6.1/go.mod h1:i06prIuMbXzDqacNJfV5OdTW448YApPu5ww/cMBSeb0=
 google.golang.org/appengine v1.6.5/go.mod h1:8WjMMxjGQR8xUklV/ARdw2HLXBOI7O7uCIDZVag1xfc=
 google.golang.org/appengine v1.6.6/go.mod h1:8WjMMxjGQR8xUklV/ARdw2HLXBOI7O7uCIDZVag1xfc=
+google.golang.org/appengine v1.6.7 h1:FZR1q0exgwxzPzp/aF+VccGrSfxfPpkBqjIIEq3ru6c=
 google.golang.org/appengine v1.6.7/go.mod h1:8WjMMxjGQR8xUklV/ARdw2HLXBOI7O7uCIDZVag1xfc=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
 google.golang.org/genproto v0.0.0-20190307195333-5fe7a883aa19/go.mod h1:VzzqZJRnGkLBvHegQrXjBqPurQTc5/KpmUdxsrq26oE=
--- a/internal/storage/azure/azure.go
+++ b/internal/storage/azure/azure.go
@@ -132,7 +132,7 @@ 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 errs []error
--- a/internal/storage/dropbox/dropbox.go
+++ b/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
+}
--- a/internal/storage/local/local.go
+++ b/internal/storage/local/local.go
@@ -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 {
@@ -125,7 +125,7 @@ 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),
 				errors.Join(removeErrors...),
 			)
--- a/internal/storage/s3/s3.go
+++ b/internal/storage/s3/s3.go
@@ -125,7 +125,12 @@ func (b *s3Storage) Copy(file string) error {

 	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)
 	}
@@ -148,7 +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,
 			)
 		}
@@ -162,7 +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 {
--- a/internal/storage/ssh/ssh.go
+++ b/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
--- a/internal/storage/storage.go
+++ b/internal/storage/storage.go
@@ -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
 }
--- a/internal/storage/webdav/webdav.go
+++ b/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
--- a/test/azure/run.sh
+++ b/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

 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
 sleep 5

 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."

+# 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
--- a/test/certs/run.sh
+++ b/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
--- a/test/cli-zstd/run.sh
+++ b/test/cli-zstd/run.sh
@@ -1,66 +0,0 @@
-#!/bin/sh
-
-set -e
-
-cd $(dirname $0)
-. ../util.sh
-current_test=$(basename $(pwd))
-
-docker network create test_network
-docker volume create backup_data
-docker volume create app_data
-# This volume is created to test whether empty directories are handled
-# correctly. It is not supposed to hold any data.
-docker volume create empty_data
-
-docker run -d \
-  --name minio \
-  --network test_network \
-  --env MINIO_ROOT_USER=test \
-  --env MINIO_ROOT_PASSWORD=test \
-  --env MINIO_ACCESS_KEY=test \
-  --env MINIO_SECRET_KEY=GMusLtUmILge2by+z890kQ \
-  -v backup_data:/data \
-  minio/minio:RELEASE.2020-08-04T23-10-51Z server /data
-
-docker exec minio mkdir -p /data/backup
-
-docker run -d \
-  --name offen \
-  --network test_network \
-  -v app_data:/var/opt/offen/ \
-  offen/offen:latest
-
-sleep 10
-
-docker run --rm \
-  --network test_network \
-  -v app_data:/backup/app_data \
-  -v empty_data:/backup/empty_data \
-  -v /var/run/docker.sock:/var/run/docker.sock \
-  --env AWS_ACCESS_KEY_ID=test \
-  --env AWS_SECRET_ACCESS_KEY=GMusLtUmILge2by+z890kQ \
-  --env AWS_ENDPOINT=minio:9000 \
-  --env AWS_ENDPOINT_PROTO=http \
-  --env AWS_S3_BUCKET_NAME=backup \
-  --env BACKUP_COMPRESSION=zst \
-  --env BACKUP_FILENAME='test.{{ .Extension }}' \
-  --env "BACKUP_FROM_SNAPSHOT=true" \
-  --entrypoint backup \
-  offen/docker-volume-backup:${TEST_VERSION:-canary}
-
-# Have to install tar and zstd on Alpine because the plain image comes with very
-# basic tar from busybox and it does not seem to support zstd
-docker run --rm \
-  -v backup_data:/data alpine \
-  ash -c 'apk add --no-cache zstd tar && tar -xvf /data/backup/test.tar.zst --zstd && test -f /backup/app_data/offen.db && test -d /backup/empty_data'
-
-pass "Found relevant files in untared remote backup."
-
-# This test does not stop containers during backup. This is happening on
-# purpose in order to cover this setup as well.
-expect_running_containers "2"
-
-docker rm $(docker stop minio offen)
-docker volume rm backup_data app_data
-docker network rm test_network
--- a/test/cli/run.sh
+++ b/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 \
+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'

--- a/test/commands/run.sh
+++ b/test/commands/run.sh
@@ -8,7 +8,7 @@ current_test=$(basename $(pwd))

 mkdir -p ./local

-docker compose up -d
+docker compose up -d --quiet-pull
 sleep 30 # mariadb likes to take a bit before responding

 docker compose exec backup backup
--- a/test/confd/run.sh
+++ b/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
--- a/test/dropbox/.gitignore
+++ b/test/dropbox/.gitignore
@@ -0,0 +1 @@
+user_v2_ready.yaml
--- a/test/dropbox/docker-compose.yml
+++ b/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: ${BACKUP_RETENTION_DAYS:-7}
+      BACKUP_PRUNING_LEEWAY: 5s
+      BACKUP_PRUNING_PREFIX: test
+      DROPBOX_ENDPOINT: http://openapi_mock:8080
+      DROPBOX_OAUTH2_ENDPOINT: http://oauth2_mock:8090
+      DROPBOX_REFRESH_TOKEN: test
+      DROPBOX_APP_KEY: test
+      DROPBOX_APP_SECRET: test
+      DROPBOX_REMOTE_PATH: /test
+      DROPBOX_CONCURRENCY_LEVEL: 6
+    volumes:
+      - app_data:/backup/app_data:ro
+      - /var/run/docker.sock:/var/run/docker.sock
+
+  offen:
+    image: offen/offen:latest
+    labels:
+      - docker-volume-backup.stop-during-backup=true
+    volumes:
+      - app_data:/var/opt/offen
+
+volumes:
+  app_data:
--- a/test/dropbox/oauth2_config.json
+++ b/test/dropbox/oauth2_config.json
@@ -0,0 +1,37 @@
+{
+   "interactiveLogin": true,
+   "httpServer": "NettyWrapper",
+   "tokenCallbacks": [
+       {
+           "issuerId": "issuer1",
+           "tokenExpiry": 120,
+           "requestMappings": [
+               {
+                   "requestParam": "scope",
+                   "match": "scope1",
+                   "claims": {
+                       "sub": "subByScope",
+                       "aud": [
+                           "audByScope"
+                       ]
+                   }
+               }
+           ]
+       },
+       {
+           "issuerId": "issuer2",
+           "requestMappings": [
+               {
+                   "requestParam": "someparam",
+                   "match": "somevalue",
+                   "claims": {
+                       "sub": "subBySomeParam",
+                       "aud": [
+                           "audBySomeParam"
+                       ]
+                   }
+               }
+           ]
+       }
+   ]
+}
--- a/test/dropbox/run.sh
+++ b/test/dropbox/run.sh
@@ -0,0 +1,65 @@
+#!/bin/sh
+
+set -e
+
+cd "$(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: $logs"
+fi
+
+
+docker compose down --volumes
+rm user_v2_ready.yaml
--- a/test/dropbox/user_v2.yaml
+++ b/test/dropbox/user_v2.yaml
--- a/test/extend/run.sh
+++ b/test/extend/run.sh
@@ -13,7 +13,7 @@ export TEST_VERSION="${TEST_VERSION:-canary}-with-rsync"

 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
--- a/test/gpg/run.sh
+++ b/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
--- a/test/ignore/run.sh
+++ b/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

--- a/test/local/run.sh
+++ b/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
--- a/test/notifications/run.sh
+++ b/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=$(curl -sSLX POST -H 'Content-Type: application/json' -d '{"name":"test"}' http://admin:custom@localhost:8080/application | jq -r '.token')
--- a/test/ownership/run.sh
+++ b/test/ownership/run.sh
@@ -9,7 +9,7 @@ current_test=$(basename $(pwd))

 mkdir -p local

-docker compose up -d
+docker compose up -d --quiet-pull
 sleep 5

 docker compose exec backup backup
--- a/test/pruning/docker-compose.yml
+++ b/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
--- a/test/pruning/run.sh
+++ b/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 $(pwd))
+
+mkdir -p local
+
+docker compose up -d --quiet-pull
+sleep 5
+
+docker compose exec backup backup
+
+sleep 5
+
+expect_running_containers "3"
+
+touch -r ./local/test-hostnametoken.tar.gz -d "14 days ago" ./local/test-hostnametoken-old.tar.gz
+
+docker run --rm \
+  -v minio_backup_data:/minio_data \
+  alpine \
+  ash -c 'touch -d@$(( $(date +%s) - 1209600 )) /minio_data/backup/test-hostnametoken-old.tar.gz'
+
+# Skip s3 backend from prune
+
+docker compose up -d
+sleep 5
+
+info "Create backup with no prune for s3 backend"
+docker compose exec backup backup
+
+info "Check if old backup has been pruned (local)"
+test ! -f ./local/test-hostnametoken-old.tar.gz
+
+info "Check if old backup has NOT been pruned (s3)"
+docker run --rm \
+  -v minio_backup_data:/minio_data \
+  alpine \
+  ash -c 'test -f /minio_data/backup/test-hostnametoken-old.tar.gz'
+
+pass "Old remote backup has been pruned locally, skipped S3 backend is untouched."
+
+# Skip local and s3 backend from prune (all backends)
+
+touch -r ./local/test-hostnametoken.tar.gz -d "14 days ago" ./local/test-hostnametoken-old.tar.gz
+
+docker compose up -d
+sleep 5
+
+info "Create backup with no prune for both backends"
+docker compose exec -e BACKUP_SKIP_BACKENDS_FROM_PRUNE="s3,local" backup backup
+
+info "Check if old backup has NOT been pruned (local)"
+test -f ./local/test-hostnametoken-old.tar.gz
+
+info "Check if old backup has NOT been pruned (s3)"
+docker run --rm \
+  -v minio_backup_data:/minio_data \
+  alpine \
+  ash -c 'test -f /minio_data/backup/test-hostnametoken-old.tar.gz'
+
+pass "Skipped all backends while pruning."
+
+docker compose down --volumes
--- a/test/s3/run.sh
+++ b/test/s3/run.sh
@@ -6,11 +6,9 @@ cd "$(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
@@ -26,7 +24,6 @@ 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

@@ -39,4 +36,28 @@ docker run --rm \

 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
--- a/test/secrets/run.sh
+++ b/test/secrets/run.sh
@@ -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
--- a/test/ssh/run.sh
+++ b/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
@@ -26,7 +26,6 @@ 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

@@ -39,5 +38,31 @@ docker run --rm \

 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
--- a/test/swarm/run.sh
+++ b/test/swarm/run.sh
@@ -29,6 +29,7 @@ sleep 5
 expect_running_containers "5"

 docker stack rm test_stack
+sleep 1
 docker swarm leave --force

 sleep 10
--- a/test/user/run.sh
+++ b/test/user/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

 user_name=testuser
 docker exec user-alpine-1 adduser --disabled-password "$user_name"
--- a/test/webdav/run.sh
+++ b/test/webdav/run.sh
@@ -6,7 +6,7 @@ cd "$(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
@@ -24,7 +24,6 @@ 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

@@ -37,4 +36,30 @@ docker run --rm \

 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
--- a/test/zstd/run.sh
+++ b/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
Author	SHA1	Message	Date
MaxJa4	43c4961116	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.	2023-08-30 20:14:24 +02:00
Frederik Ring	24a6ec9480	Dropbox was missing from notification docs	2023-08-28 20:42:45 +02:00
MaxJa4	ad4e2af83f	Exclude specific backends from pruning (#262 ) * Skip backends while pruning * Add pruning test step and silence download log for better readability * Add test cases for pruning in all backends Also add -q or --quiet-pull to all tests. * Add test case for skipping backends while pruning * Adjusted test logging, generate new test spec file * Gitignore for temp test file	2023-08-27 19:19:11 +02:00
MaxJa4	5fcc96edf9	Cleanup: Lint warnings and deprecated packages (#263 ) * Fix lint warnings and std lib deprecations * Replace deprecated std lib with maintained drop-in replacement fork Backwartds compatible with original package and suggested by std lib due to security and stability issues. * OAuth2 is now a direct dependency due to Dropbox * Undo change * Revert "Replace deprecated std lib with maintained drop-in replacement fork" This reverts commit `2887bd409f`. * Update channel handling * Add linter for PRs * Rename CI, fetch all issues, add govet	2023-08-27 18:14:55 +02:00
Frederik Ring	3d7677f02a	Print context in log field instead of prepending to message (#260 ) * Print context in log field instead of prepending to message * Log messages on pruning do not need a description anymore * Remove redundant information from logs and errors	2023-08-25 12:44:43 +02:00
Frederik Ring	88a4794083	Zstd test does not need to spin up MinIO server (#258 )	2023-08-24 22:14:04 +02:00
Frederik Ring	7011261dc5	Pin version of mock openapi server used in Dropbox test	2023-08-24 22:01:07 +02:00
Frederik Ring	9ba8143be2	Add license headers to vendored Dropbox swagger spec	2023-08-24 19:52:33 +02:00
dependabot[bot]	b90fc9ea4d	Bump github.com/minio/minio-go/v7 from 7.0.61 to 7.0.62 (#255 ) Bumps [github.com/minio/minio-go/v7](https://github.com/minio/minio-go) from 7.0.61 to 7.0.62. - [Release notes](https://github.com/minio/minio-go/releases) - [Commits](https://github.com/minio/minio-go/compare/v7.0.61...v7.0.62) --- updated-dependencies: - dependency-name: github.com/minio/minio-go/v7 dependency-type: direct:production update-type: version-update:semver-patch ... Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>	2023-08-24 19:37:50 +02:00
MaxJa4	e08a3303bf	Add new storage backend: Dropbox (#103 ) (#251 ) * Add new storage backend: Dropbox (#103) * Remove duplicate check * Add concurrency level for parallel upload to dropbox. * Fixed some instabilites. Changed default concurrency to 6. * Added some env config vars to readme. WIP * Wrap errors for storage backend creation. * Fixed token issue, added OAuth2 including recipe and docs. * Readme typo fix * Test for dropbox integration * Update info and TOC * Missed a file * Docker-compose fix * Fix endpoint connection * Fix container names * Fix log fetching * Fix log fetching (again) * Print command output to logs * Addressing comments part 1 * Address comments part 2 * OpenAPI Mock spec path adjusted * Dropbox FileMetadata reflection refactored * NaturalNumber type added * Add OAuth2 mock server for CI testing * Fix env name of oauth2 endpoint * Remove hostname * Add forgotten change to commit... * Fix oauth2 endpoint "Worked on my machine" * Try again * Try suggested hostname again * Fix docker internal DNS resolving issues (as suggested by oauth2 mock docs) * Add docker network, remove hostname * Network not external * Last hostname try * Add more delay, add oauth2 endpoint log * Temp CI log output of command even when failing * Try different config and method * Add custom server-hostname. Rename test folder to accellerate debugging * Try that fix again * Adding quotes * Port fix attempt * Try localhost * Try extra hosts * Change network mode * Undo some changes * Use static IP * Remove specific IP binding * Change to default net driver * Fix static IP * Squash for revert * Revert "Squash for revert" This reverts commit `e9b617be9a`. * Actual fix for CI testing from #257	2023-08-24 19:33:47 +02:00
MaxJa4	47326c7c59	Fix storage backends not outputting any info logs (#250 )	2023-08-20 20:35:25 +02:00