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14 Commits

Author SHA1 Message Date
Frederik Ring
f15379795f fix location of success message for having created local backup 2021-08-22 20:49:46 +02:00
Frederik Ring
053422ba0e only tag proper releases as latest 2021-08-22 20:16:24 +02:00
Frederik Ring
39b933b8e8 improve logging messages 2021-08-22 20:03:18 +02:00
Frederik Ring
8161ad7f8f add insecure option, update docs 2021-08-22 19:26:34 +02:00
Frederik Ring
34e01fa303 adapt repo layout to go 2021-08-22 18:16:40 +02:00
Frederik Ring
2554c538ea add logging 2021-08-22 18:00:10 +02:00
Frederik Ring
77f948d4da refactor deferred cleanup actions to always run 2021-08-22 16:19:41 +02:00
Frederik Ring
d388785222 implement pruning from remote storage 2021-08-22 15:17:23 +02:00
Frederik Ring
b46c402b19 add gpg encryption 2021-08-22 14:44:33 +02:00
Frederik Ring
29f8a078bc implement deletion of local backups 2021-08-22 14:19:25 +02:00
Frederik Ring
3f7c08d616 implement lock file to ensure backup runs mutually exclusive 2021-08-22 12:02:22 +02:00
Frederik Ring
8b7d27740a implement copy to remote storage 2021-08-21 21:38:26 +02:00
Frederik Ring
9ddddc139a scaffold script flow 2021-08-21 19:55:22 +02:00
Frederik Ring
d34b525804 try porting docker related parts to golang 2021-08-21 19:05:49 +02:00
8 changed files with 109 additions and 135 deletions

View File

@@ -11,10 +11,6 @@ jobs:
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

View File

@@ -2,7 +2,7 @@
Backup Docker volumes locally or to any S3 compatible storage.
The [offen/docker-volume-backup](https://hub.docker.com/r/offen/docker-volume-backup) Docker image can be used as a lightweight (below 15MB) sidecar container to an existing Docker setup. It handles recurring backups of Docker volumes to a local directory or any S3 compatible storage (or both), and rotates away old backups if configured.
The [offen/docker-volume-backup](https://hub.docker.com/r/offen/docker-volume-backup) Docker image can be used as a sidecar container to an existing Docker setup. It handles recurring backups of Docker volumes to a local directory or any S3 compatible storage (or both) and rotates away old backups if configured.
## Configuration
@@ -79,7 +79,7 @@ AWS_S3_BUCKET_NAME="<xxx>"
# that is expected to be bigger than the maximum difference of backups.
# Valid values have a suffix of (s)econds, (m)inutes or (h)ours.
# BACKUP_PRUNING_LEEWAY="1m"
# BACKUP_PRUNING_LEEWAY="10m"
# In case your target bucket or directory contains other files than the ones
# managed by this container, you can limit the scope of rotation by setting
@@ -177,8 +177,8 @@ docker exec <container_ref> backup
This image is heavily inspired by the `futurice/docker-volume-backup`. We decided to publish this image as a simpler and more lightweight alternative because of the following requirements:
- The original image is based on `ubuntu` and additional tools, making it very heavy. This version is roughly 1/25 in compressed size (it's ~12MB).
- The original image uses a shell script, when this is written in Go, which makes it easier to extend and maintain (more verbose also).
- The original image uses a shell script, when this is written in Go.
- The original image proposed to handle backup rotation through AWS S3 lifecycle policies. This image adds the option to rotate away old backups through the same command so this functionality can also be offered for non-AWS storage backends like MinIO. Local copies of backups can also be pruned once they reach a certain age.
- InfluxDB specific functionality from the original image was removed.
- InfluxDB specific functionality was removed.
- `arm64` and `arm/v7` architectures are supported.
- Docker in Swarm mode is supported.

View File

@@ -4,7 +4,6 @@
package main
import (
"bufio"
"bytes"
"context"
"errors"
@@ -12,9 +11,11 @@ import (
"io"
"io/ioutil"
"os"
"os/exec"
"path"
"path/filepath"
"strconv"
"strings"
"time"
"github.com/docker/docker/api/types"
@@ -22,7 +23,6 @@ import (
"github.com/docker/docker/api/types/swarm"
"github.com/docker/docker/client"
"github.com/joho/godotenv"
"github.com/leekchan/timeutil"
minio "github.com/minio/minio-go/v7"
"github.com/minio/minio-go/v7/pkg/credentials"
"github.com/sirupsen/logrus"
@@ -44,31 +44,39 @@ func main() {
s.logger.Info("Finished running backup tasks.")
}
// script holds all the stateful information required to orchestrate a
// single backup run.
type script struct {
ctx context.Context
cli *client.Client
mc *minio.Client
logger *logrus.Logger
ctx context.Context
cli *client.Client
mc *minio.Client
logger *logrus.Logger
file string
bucket string
archive string
sources string
passphrase string
}
start time.Time
file string
bucket string
archive string
sources string
passphrase []byte
retentionDays *int
leeway *time.Duration
containerLabel string
pruningPrefix string
// lock opens a lockfile at the given location, keeping it locked until the
// caller invokes the returned release func. When invoked while the file is
// still locked the function panics.
func lock(lockfile string) func() error {
lf, err := os.OpenFile(lockfile, os.O_CREATE, os.ModeAppend)
if err != nil {
panic(err)
}
return func() error {
if err := lf.Close(); err != nil {
return fmt.Errorf("lock: error releasing file lock: %w", err)
}
if err := os.Remove(lockfile); err != nil {
return fmt.Errorf("lock: error removing lock file: %w", err)
}
return nil
}
}
// init creates all resources needed for the script to perform actions against
// remote resources like the Docker engine or remote storage locations. All
// reading from env vars or other configuration sources is expected to happen
// in this method.
// remote resources like the Docker engine or remote storage locations.
func (s *script) init() error {
s.ctx = context.Background()
s.logger = logrus.New()
@@ -110,27 +118,7 @@ func (s *script) init() error {
s.file = path.Join("/tmp", file)
s.archive = os.Getenv("BACKUP_ARCHIVE")
s.sources = os.Getenv("BACKUP_SOURCES")
if v := os.Getenv("GPG_PASSPHRASE"); v != "" {
s.passphrase = []byte(v)
}
if v := os.Getenv("BACKUP_RETENTION_DAYS"); v != "" {
i, err := strconv.Atoi(v)
if err != nil {
return fmt.Errorf("init: error parsing BACKUP_RETENTION_DAYS as int: %w", err)
}
s.retentionDays = &i
}
if v := os.Getenv("BACKUP_PRUNING_LEEWAY"); v != "" {
d, err := time.ParseDuration(v)
if err != nil {
return fmt.Errorf("init: error parsing BACKUP_PRUNING_LEEWAY as duration: %w", err)
}
s.leeway = &d
}
s.containerLabel = os.Getenv("BACKUP_STOP_CONTAINER_LABEL")
s.pruningPrefix = os.Getenv("BACKUP_PRUNING_PREFIX")
s.start = time.Now()
s.passphrase = os.Getenv("GPG_PASSPHRASE")
return nil
}
@@ -139,9 +127,8 @@ func (s *script) init() error {
// sure containers are being restarted if required.
func (s *script) stopContainersAndRun(thunk func() error) error {
if s.cli == nil {
return thunk()
return nil
}
allContainers, err := s.cli.ContainerList(s.ctx, types.ContainerListOptions{
Quiet: true,
})
@@ -151,7 +138,7 @@ func (s *script) stopContainersAndRun(thunk func() error) error {
containerLabel := fmt.Sprintf(
"docker-volume-backup.stop-during-backup=%s",
s.containerLabel,
os.Getenv("BACKUP_STOP_CONTAINER_LABEL"),
)
containersToStop, err := s.cli.ContainerList(s.ctx, types.ContainerListOptions{
Quiet: true,
@@ -164,25 +151,22 @@ func (s *script) stopContainersAndRun(thunk func() error) error {
if err != nil {
return fmt.Errorf("stopContainersAndRun: error querying for containers to stop: %w", err)
}
if len(containersToStop) == 0 {
return thunk()
}
s.logger.Infof(
"Stopping %d container(s) labeled `%s` out of %d running container(s).",
"Stopping %d containers labeled `%s` out of %d running containers.",
len(containersToStop),
containerLabel,
len(allContainers),
)
var stoppedContainers []types.Container
var stopErrors []error
for _, container := range containersToStop {
if err := s.cli.ContainerStop(s.ctx, container.ID, nil); err != nil {
stopErrors = append(stopErrors, err)
} else {
stoppedContainers = append(stoppedContainers, container)
var errors []error
if len(containersToStop) != 0 {
for _, container := range containersToStop {
if err := s.cli.ContainerStop(s.ctx, container.ID, nil); err != nil {
errors = append(errors, err)
} else {
stoppedContainers = append(stoppedContainers, container)
}
}
}
@@ -231,17 +215,21 @@ func (s *script) stopContainersAndRun(thunk func() error) error {
err,
)
}
s.logger.Infof("Restarted %d container(s) and the matching service(s).", len(stoppedContainers))
s.logger.Infof("Successfully restarted %d containers.", len(stoppedContainers))
return nil
}()
if len(stopErrors) != 0 {
return fmt.Errorf(
"stopContainersAndRun: %d error(s) stopping containers: %w",
len(stopErrors),
var stopErr error
if len(errors) != 0 {
stopErr = fmt.Errorf(
"stopContainersAndRun: %d errors stopping containers: %w",
len(errors),
err,
)
}
if stopErr != nil {
return stopErr
}
return thunk()
}
@@ -249,11 +237,15 @@ func (s *script) stopContainersAndRun(thunk func() error) error {
// takeBackup creates a tar archive of the configured backup location and
// saves it to disk.
func (s *script) takeBackup() error {
s.file = timeutil.Strftime(&s.start, s.file)
outBytes, err := exec.Command("date", fmt.Sprintf("+%s", s.file)).Output()
if err != nil {
return fmt.Errorf("takeBackup: error formatting filename template: %w", err)
}
s.file = strings.TrimSpace(string(outBytes))
if err := targz.Compress(s.sources, s.file); err != nil {
return fmt.Errorf("takeBackup: error compressing backup folder: %w", err)
}
s.logger.Infof("Created backup of `%s` at `%s`.", s.sources, s.file)
s.logger.Infof("Successfully created backup of `%s` at `%s`.", s.sources, s.file)
return nil
}
@@ -261,14 +253,13 @@ func (s *script) takeBackup() error {
// In case no passphrase is given it returns early, leaving the backup file
// untouched.
func (s *script) encryptBackup() error {
if s.passphrase == nil {
if s.passphrase == "" {
return nil
}
output := bytes.NewBuffer(nil)
buf := bytes.NewBuffer(nil)
_, name := path.Split(s.file)
pt, err := openpgp.SymmetricallyEncrypt(output, []byte(s.passphrase), &openpgp.FileHints{
pt, err := openpgp.SymmetricallyEncrypt(buf, []byte(s.passphrase), &openpgp.FileHints{
IsBinary: true,
FileName: name,
}, nil)
@@ -276,25 +267,28 @@ func (s *script) encryptBackup() error {
return fmt.Errorf("encryptBackup: error encrypting backup file: %w", err)
}
file, err := os.Open(s.file)
unencrypted, err := ioutil.ReadFile(s.file)
if err != nil {
return fmt.Errorf("encryptBackup: error opening backup file %s: %w", s.file, err)
pt.Close()
return fmt.Errorf("encryptBackup: error reading unencrypted backup file: %w", err)
}
_, err = pt.Write(unencrypted)
if err != nil {
pt.Close()
return fmt.Errorf("encryptBackup: error writing backup contents: %w", err)
}
fileReader := bufio.NewReader(file)
fileReader.WriteTo(pt)
pt.Close()
gpgFile := fmt.Sprintf("%s.gpg", s.file)
if err := ioutil.WriteFile(gpgFile, output.Bytes(), os.ModeAppend); err != nil {
if err := ioutil.WriteFile(gpgFile, buf.Bytes(), os.ModeAppend); err != nil {
return fmt.Errorf("encryptBackup: error writing encrypted version of backup: %w", err)
}
if err := os.Remove(s.file); err != nil {
return fmt.Errorf("encryptBackup: error removing unencrpyted backup: %w", err)
}
s.file = gpgFile
s.logger.Infof("Encrypted backup using given passphrase, saving as `%s`.", s.file)
s.logger.Infof("Successfully encrypted backup using given passphrase, saving as `%s`.", s.file)
return nil
}
@@ -309,14 +303,14 @@ func (s *script) copyBackup() error {
if err != nil {
return fmt.Errorf("copyBackup: error uploading backup to remote storage: %w", err)
}
s.logger.Infof("Uploaded a copy of backup `%s` to bucket `%s`", s.file, s.bucket)
s.logger.Infof("Successfully uploaded a copy of backup `%s` to bucket `%s`", s.file, s.bucket)
}
if _, err := os.Stat(s.archive); !os.IsNotExist(err) {
if err := copy(s.file, path.Join(s.archive, name)); err != nil {
return fmt.Errorf("copyBackup: error copying file to local archive: %w", err)
}
s.logger.Infof("Stored copy of backup `%s` in local archive `%s`", s.file, s.archive)
s.logger.Infof("Successfully stored copy of backup `%s` in local archive `%s`", s.file, s.archive)
}
return nil
}
@@ -326,7 +320,7 @@ func (s *script) cleanBackup() error {
if err := os.Remove(s.file); err != nil {
return fmt.Errorf("cleanBackup: error removing file: %w", err)
}
s.logger.Info("Cleaned up local artifacts.")
s.logger.Info("Successfully cleaned up local artifacts.")
return nil
}
@@ -334,22 +328,29 @@ func (s *script) cleanBackup() error {
// the given configuration. In case the given configuration would delete all
// backups, it does nothing instead.
func (s *script) pruneOldBackups() error {
if s.retentionDays == nil {
retention := os.Getenv("BACKUP_RETENTION_DAYS")
if retention == "" {
return nil
}
if s.leeway != nil {
s.logger.Infof("Sleeping for %s before pruning backups.", s.leeway)
time.Sleep(*s.leeway)
retentionDays, err := strconv.Atoi(retention)
if err != nil {
return fmt.Errorf("pruneOldBackups: error parsing BACKUP_RETENTION_DAYS as int: %w", err)
}
leeway := os.Getenv("BACKUP_PRUNING_LEEWAY")
sleepFor, err := time.ParseDuration(leeway)
if err != nil {
return fmt.Errorf("pruneBackups: error parsing given leeway value: %w", err)
}
s.logger.Infof("Sleeping for %s before pruning backups.", leeway)
time.Sleep(sleepFor)
s.logger.Infof("Trying to prune backups older than %d day(s) now.", *s.retentionDays)
deadline := s.start.AddDate(0, 0, -*s.retentionDays)
s.logger.Infof("Trying to prune backups older than %d days now.", retentionDays)
deadline := time.Now().AddDate(0, 0, -retentionDays)
if s.bucket != "" {
candidates := s.mc.ListObjects(s.ctx, s.bucket, minio.ListObjectsOptions{
WithMetadata: true,
Prefix: s.pruningPrefix,
Prefix: os.Getenv("BACKUP_PRUNING_PREFIX"),
})
var matches []minio.ObjectInfo
@@ -382,13 +383,13 @@ func (s *script) pruneOldBackups() error {
if len(errors) != 0 {
return fmt.Errorf(
"pruneOldBackups: %d error(s) removing files from remote storage: %w",
"pruneOldBackups: %d errors removing files from remote storage: %w",
len(errors),
errors[0],
)
}
s.logger.Infof(
"Pruned %d out of %d remote backup(s) as their age exceeded the configured retention period.",
"Successfully pruned %d out of %d remote backups as their age exceeded the configured retention period.",
len(matches),
lenCandidates,
)
@@ -398,13 +399,13 @@ func (s *script) pruneOldBackups() error {
len(matches),
)
} else {
s.logger.Infof("None of %d remote backup(s) were pruned.", lenCandidates)
s.logger.Infof("None of %d remote backups were pruned.", lenCandidates)
}
}
if _, err := os.Stat(s.archive); !os.IsNotExist(err) {
candidates, err := filepath.Glob(
path.Join(s.archive, fmt.Sprintf("%s*", s.pruningPrefix)),
path.Join(s.archive, fmt.Sprintf("%s*", os.Getenv("BACKUP_PRUNING_PREFIX"))),
)
if err != nil {
return fmt.Errorf(
@@ -412,7 +413,7 @@ func (s *script) pruneOldBackups() error {
)
}
var matches []string
var matches []os.FileInfo
for _, candidate := range candidates {
fi, err := os.Stat(candidate)
if err != nil {
@@ -424,26 +425,26 @@ func (s *script) pruneOldBackups() error {
}
if fi.ModTime().Before(deadline) {
matches = append(matches, candidate)
matches = append(matches, fi)
}
}
if len(matches) != 0 && len(matches) != len(candidates) {
var errors []error
for _, candidate := range matches {
if err := os.Remove(candidate); err != nil {
if err := os.Remove(candidate.Name()); err != nil {
errors = append(errors, err)
}
}
if len(errors) != 0 {
return fmt.Errorf(
"pruneOldBackups: %d error(s) deleting local files, starting with: %w",
"pruneOldBackups: %d errors deleting local files, starting with: %w",
len(errors),
errors[0],
)
}
s.logger.Infof(
"Pruned %d out of %d local backup(s) as their age exceeded the configured retention period.",
"Successfully pruned %d out of %d local backups as their age exceeded the configured retention period.",
len(matches),
len(candidates),
)
@@ -453,7 +454,7 @@ func (s *script) pruneOldBackups() error {
len(matches),
)
} else {
s.logger.Infof("None of %d local backup(s) were pruned.", len(candidates))
s.logger.Infof("None of %d local backups were pruned.", len(candidates))
}
}
return nil
@@ -469,26 +470,6 @@ func (s *script) must(err error) {
}
}
// lock opens a lockfile at the given location, keeping it locked until the
// caller invokes the returned release func. When invoked while the file is
// still locked the function panics.
func lock(lockfile string) func() error {
lf, err := os.OpenFile(lockfile, os.O_CREATE|os.O_RDWR, os.ModeAppend)
if err != nil {
panic(err)
}
return func() error {
if err := lf.Close(); err != nil {
return fmt.Errorf("lock: error releasing file lock: %w", err)
}
if err := os.Remove(lockfile); err != nil {
return fmt.Errorf("lock: error removing lock file: %w", err)
}
return nil
}
}
// copy creates a copy of the file located at `dst` at `src`.
func copy(src, dst string) error {
in, err := os.Open(src)
if err != nil {

View File

@@ -9,6 +9,7 @@
set -e
# Write cronjob env to file, fill in sensible defaults, and read them back in
mkdir -p /etc/backup
cat <<EOF > /etc/backup.env
BACKUP_SOURCES="${BACKUP_SOURCES:-/backup}"
BACKUP_CRON_EXPRESSION="${BACKUP_CRON_EXPRESSION:-@daily}"
@@ -16,7 +17,7 @@ BACKUP_FILENAME="${BACKUP_FILENAME:-backup-%Y-%m-%dT%H-%M-%S.tar.gz}"
BACKUP_ARCHIVE="${BACKUP_ARCHIVE:-/archive}"
BACKUP_RETENTION_DAYS="${BACKUP_RETENTION_DAYS:-}"
BACKUP_PRUNING_LEEWAY="${BACKUP_PRUNING_LEEWAY:-1m}"
BACKUP_PRUNING_LEEWAY="${BACKUP_PRUNING_LEEWAY:-10m}"
BACKUP_PRUNING_PREFIX="${BACKUP_PRUNING_PREFIX:-}"
BACKUP_STOP_CONTAINER_LABEL="${BACKUP_STOP_CONTAINER_LABEL:-true}"

3
go.mod
View File

@@ -5,9 +5,7 @@ go 1.17
require (
github.com/docker/docker v20.10.8+incompatible
github.com/joho/godotenv v1.3.0
github.com/leekchan/timeutil v0.0.0-20150802142658-28917288c48d
github.com/minio/minio-go/v7 v7.0.12
github.com/sirupsen/logrus v1.8.1
github.com/walle/targz v0.0.0-20140417120357-57fe4206da5a
golang.org/x/crypto v0.0.0-20210817164053-32db794688a5
)
@@ -34,6 +32,7 @@ require (
github.com/opencontainers/image-spec v1.0.1 // indirect
github.com/pkg/errors v0.9.1 // indirect
github.com/rs/xid v1.2.1 // indirect
github.com/sirupsen/logrus v1.8.1 // indirect
golang.org/x/net v0.0.0-20210226172049-e18ecbb05110 // indirect
golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1 // indirect
golang.org/x/text v0.3.4 // indirect

2
go.sum
View File

@@ -401,8 +401,6 @@ github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfn
github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
github.com/kr/pty v1.1.5/go.mod h1:9r2w37qlBe7rQ6e1fg1S/9xpWHSnaqNdHD3WcMdbPDA=
github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
github.com/leekchan/timeutil v0.0.0-20150802142658-28917288c48d h1:2puqoOQwi3Ai1oznMOsFIbifm6kIfJaLLyYzWD4IzTs=
github.com/leekchan/timeutil v0.0.0-20150802142658-28917288c48d/go.mod h1:hO90vCP2x3exaSH58BIAowSKvV+0OsY21TtzuFGHON4=
github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
github.com/mailru/easyjson v0.0.0-20190614124828-94de47d64c63/go.mod h1:C1wdFJiN94OJF2b5HbByQZoLdCWB1Yqtg26g4irojpc=
github.com/mailru/easyjson v0.0.0-20190626092158-b2ccc519800e/go.mod h1:C1wdFJiN94OJF2b5HbByQZoLdCWB1Yqtg26g4irojpc=

View File

@@ -28,7 +28,6 @@ services:
BACKUP_RETENTION_DAYS: ${BACKUP_RETENTION_DAYS:-7}
BACKUP_PRUNING_LEEWAY: 5s
BACKUP_PRUNING_PREFIX: test
GPG_PASSPHRASE: 1234secret
volumes:
- ./local:/archive
- app_data:/backup/app_data:ro

View File

@@ -13,13 +13,11 @@ docker-compose exec backup backup
docker run --rm -it \
-v compose_backup_data:/data alpine \
ash -c 'apk add gnupg && echo 1234secret | gpg -d --pinentry-mode loopback --passphrase-fd 0 --yes /data/backup/test.tar.gz.gpg > /tmp/test.tar.gz && tar -xf /tmp/test.tar.gz -C /tmp && test -f /tmp/backup/app_data/offen.db'
ash -c 'tar -xf /data/backup/test.tar.gz && test -f /backup/app_data/offen.db'
echo "[TEST:PASS] Found relevant files in untared remote backup."
echo 1234secret | gpg -d --yes --passphrase-fd 0 ./local/test.tar.gz.gpg > ./local/decrypted.tar.gz
tar -xf ./local/decrypted.tar.gz -C /tmp && test -f /tmp/backup/app_data/offen.db
rm ./local/decrypted.tar.gz
tar -xf ./local/test.tar.gz -C /tmp && test -f /tmp/backup/app_data/offen.db
echo "[TEST:PASS] Found relevant files in untared local backup."
@@ -31,6 +29,8 @@ fi
echo "[TEST:PASS] All containers running post backup."
docker-compose down
# 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