improve logging messages

This commit is contained in:
Frederik Ring 2021-08-22 19:37:48 +02:00
parent 8161ad7f8f
commit 39b933b8e8
2 changed files with 59 additions and 50 deletions

View File

@ -1,6 +1,3 @@
# Copyright 2020 - Offen Authors <hioffen@posteo.de>
# SPDX-License-Identifier: Apache-2.0
# EditorConfig is awesome: http://EditorConfig.org
# top-most EditorConfig file

View File

@ -31,23 +31,16 @@ import (
)
func main() {
unlock, err := lock("/var/dockervolumebackup.lock")
if err != nil {
panic(err)
}
unlock := lock("/var/dockervolumebackup.lock")
defer unlock()
s := &script{}
must(s.init)()
err = s.stopContainersAndRun(s.takeBackup)
if err != nil {
panic(err)
}
must(s.encryptBackup)()
must(s.copyBackup)()
must(s.cleanBackup)()
must(s.pruneOldBackups)()
s.must(s.init())
s.must(s.stopContainersAndRun(s.takeBackup))
s.must(s.encryptBackup())
s.must(s.copyBackup())
s.must(s.cleanBackup())
s.must(s.pruneOldBackups())
}
type script struct {
@ -58,14 +51,17 @@ type script struct {
file string
bucket string
archive string
sources string
passphrase string
}
// lock opens a lockfile, keeping it open until the caller invokes the returned
// release func.
func lock(lockfile string) (func() error, 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.ModeAppend)
if err != nil {
return nil, fmt.Errorf("lock: error opening lock file: %w", err)
panic(err)
}
return func() error {
if err := lf.Close(); err != nil {
@ -75,7 +71,7 @@ func lock(lockfile string) (func() error, error) {
return fmt.Errorf("lock: error removing lock file: %w", err)
}
return nil
}, nil
}
}
// init creates all resources needed for the script to perform actions against
@ -120,6 +116,8 @@ func (s *script) init() error {
}
s.file = path.Join("/tmp", file)
s.archive = os.Getenv("BACKUP_ARCHIVE")
s.sources = os.Getenv("BACKUP_SOURCES")
s.passphrase = os.Getenv("GPG_PASSPHRASE")
return nil
}
@ -137,21 +135,27 @@ func (s *script) stopContainersAndRun(thunk func() error) error {
return fmt.Errorf("stopContainersAndRun: error querying for containers: %w", err)
}
containerLabel := fmt.Sprintf(
"docker-volume-backup.stop-during-backup=%s",
os.Getenv("BACKUP_STOP_CONTAINER_LABEL"),
)
containersToStop, err := s.cli.ContainerList(s.ctx, types.ContainerListOptions{
Quiet: true,
Filters: filters.NewArgs(filters.KeyValuePair{
Key: "label",
Value: fmt.Sprintf(
"docker-volume-backup.stop-during-backup=%s",
os.Getenv("BACKUP_STOP_CONTAINER_LABEL"),
),
Value: containerLabel,
}),
})
if err != nil {
return fmt.Errorf("stopContainersAndRun: error querying for containers to stop: %w", err)
}
s.logger.Infof("Stopping %d out of %d running containers\n", len(containersToStop), len(allContainers))
s.logger.Infof(
"Stopping %d containers labeled `%s` out of %d running containers.",
len(containersToStop),
containerLabel,
len(allContainers),
)
var stoppedContainers []types.Container
var errors []error
@ -237,10 +241,10 @@ func (s *script) takeBackup() error {
return fmt.Errorf("takeBackup: error formatting filename template: %w", err)
}
s.file = strings.TrimSpace(string(outBytes))
if err := targz.Compress(os.Getenv("BACKUP_SOURCES"), s.file); err != nil {
if err := targz.Compress(s.sources, s.file); err != nil {
return fmt.Errorf("takeBackup: error compressing backup folder: %w", err)
}
s.logger.Infof("Successfully created backup from %s at %s", os.Getenv("BACKUP_SOURCES"), s.file)
s.logger.Infof("Successfully created backup of `%s` at `%s`.", s.sources, s.file)
return nil
}
@ -248,14 +252,13 @@ func (s *script) takeBackup() error {
// In case no passphrase is given it returns early, leaving the backup file
// untouched.
func (s *script) encryptBackup() error {
passphrase := os.Getenv("GPG_PASSPHRASE")
if passphrase == "" {
if s.passphrase == "" {
return nil
}
buf := bytes.NewBuffer(nil)
_, name := path.Split(s.file)
pt, err := openpgp.SymmetricallyEncrypt(buf, []byte(passphrase), &openpgp.FileHints{
pt, err := openpgp.SymmetricallyEncrypt(buf, []byte(s.passphrase), &openpgp.FileHints{
IsBinary: true,
FileName: name,
}, nil)
@ -284,7 +287,7 @@ func (s *script) encryptBackup() error {
return fmt.Errorf("encryptBackup: error removing unencrpyted backup: %w", err)
}
s.file = gpgFile
s.logger.Info("Successfully encrypted backup using given passphrase.")
s.logger.Infof("Successfully encrypted backup using given passphrase, saving as `%s`.", s.file)
return nil
}
@ -299,7 +302,7 @@ func (s *script) copyBackup() error {
if err != nil {
return fmt.Errorf("copyBackup: error uploading backup to remote storage: %w", err)
}
s.logger.Infof("Successfully uploaded 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 s.archive != "" {
@ -308,7 +311,7 @@ func (s *script) copyBackup() error {
return fmt.Errorf("copyBackup: error copying file to local archive: %w", err)
}
}
s.logger.Infof("Successfully 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
}
@ -334,11 +337,12 @@ func (s *script) pruneOldBackups() error {
if err != nil {
return fmt.Errorf("pruneOldBackups: error parsing BACKUP_RETENTION_DAYS as int: %w", err)
}
sleepFor, err := time.ParseDuration(os.Getenv("BACKUP_PRUNING_LEEWAY"))
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.", os.Getenv("BACKUP_PRUNING_LEEWAY"))
s.logger.Infof("Sleeping for %s before pruning backups.", leeway)
time.Sleep(sleepFor)
s.logger.Infof("Trying to prune backups older than %d days now.", retentionDays)
@ -391,7 +395,10 @@ func (s *script) pruneOldBackups() error {
lenCandidates,
)
} else if len(matches) != 0 && len(matches) == lenCandidates {
s.logger.Warnf("The current configuration would delete all %d remote backups. Refusing to do so.", len(matches))
s.logger.Warnf(
"The current configuration would delete all %d remote backup copies. Refusing to do so, please check your configuration.",
len(matches),
)
} else {
s.logger.Infof("None of %d remote backups were pruned.", lenCandidates)
}
@ -443,7 +450,10 @@ func (s *script) pruneOldBackups() error {
len(candidates),
)
} else if len(matches) != 0 && len(matches) == len(candidates) {
s.logger.Warnf("The current configuration would delete all %d local backups. Refusing to do so.", len(matches))
s.logger.Warnf(
"The current configuration would delete all %d local backup copies. Refusing to do so, please check your configuration.",
len(matches),
)
} else {
s.logger.Infof("None of %d local backups were pruned.", len(candidates))
}
@ -451,11 +461,13 @@ func (s *script) pruneOldBackups() error {
return nil
}
func must(f func() error) func() {
return func() {
if err := f(); err != nil {
func (s *script) must(err error) {
if err != nil {
if s.logger == nil {
panic(err)
}
s.logger.Errorf("Fatal error running backup: %s", err)
os.Exit(1)
}
}