docker-volume-backup/internal/storage/local/local.go

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// Copyright 2022 - Offen Authors <hioffen@posteo.de>
// SPDX-License-Identifier: MPL-2.0
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
package local
import (
"fmt"
"io"
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
"os"
"path"
"path/filepath"
"time"
"github.com/offen/docker-volume-backup/internal/storage"
"github.com/offen/docker-volume-backup/internal/utilities"
)
type localStorage struct {
*storage.StorageBackend
latestSymlink string
}
// Config allows configuration of a local storage backend.
type Config struct {
ArchivePath string
LatestSymlink string
}
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
// NewStorageBackend creates and initializes a new local storage backend.
func NewStorageBackend(opts Config, logFunc storage.Log) storage.Backend {
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
return &localStorage{
StorageBackend: &storage.StorageBackend{
DestinationPath: opts.ArchivePath,
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
Log: logFunc,
},
latestSymlink: opts.LatestSymlink,
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
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}
}
// Name return the name of the storage backend
func (b *localStorage) Name() string {
return "Local"
}
// Copy copies the given file to the local storage backend.
func (b *localStorage) Copy(file string) error {
_, name := path.Split(file)
if err := copyFile(file, path.Join(b.DestinationPath, name)); err != nil {
return fmt.Errorf("(*localStorage).Copy: Error copying file to local archive! %w", err)
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
}
b.Log(storage.LogLevelInfo, b.Name(), "Stored copy of backup `%s` in local archive `%s`.", file, b.DestinationPath)
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
if b.latestSymlink != "" {
symlink := path.Join(b.DestinationPath, b.latestSymlink)
if _, err := os.Lstat(symlink); err == nil {
os.Remove(symlink)
}
if err := os.Symlink(name, symlink); err != nil {
return fmt.Errorf("(*localStorage).Copy: error creating latest symlink! %w", err)
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
}
b.Log(storage.LogLevelInfo, b.Name(), "Created/Updated symlink `%s` for latest backup.", b.latestSymlink)
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
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}
return nil
}
// Prune rotates away backups according to the configuration and provided deadline for the local storage backend.
func (b *localStorage) Prune(deadline time.Time, pruningPrefix string) (*storage.PruneStats, error) {
globPattern := path.Join(
b.DestinationPath,
fmt.Sprintf("%s*", pruningPrefix),
)
globMatches, err := filepath.Glob(globPattern)
if err != nil {
return nil, fmt.Errorf(
"(*localStorage).Prune: Error looking up matching files using pattern %s: %w",
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
globPattern,
err,
)
}
var candidates []string
for _, candidate := range globMatches {
fi, err := os.Lstat(candidate)
if err != nil {
return nil, fmt.Errorf(
"(*localStorage).Prune: Error calling Lstat on file %s: %w",
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
candidate,
err,
)
}
if fi.Mode()&os.ModeSymlink != os.ModeSymlink {
candidates = append(candidates, candidate)
}
}
var matches []string
for _, candidate := range candidates {
fi, err := os.Stat(candidate)
if err != nil {
return nil, fmt.Errorf(
"(*localStorage).Prune: Error calling stat on file %s! %w",
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
candidate,
err,
)
}
if fi.ModTime().Before(deadline) {
matches = append(matches, candidate)
}
}
stats := &storage.PruneStats{
Total: uint(len(candidates)),
Pruned: uint(len(matches)),
}
if err := b.DoPrune(b.Name(), len(matches), len(candidates), "local backup(s)", func() error {
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
var removeErrors []error
for _, match := range matches {
if err := os.Remove(match); err != nil {
removeErrors = append(removeErrors, err)
}
}
if len(removeErrors) != 0 {
return fmt.Errorf(
"(*localStorage).Prune: %d error(s) deleting local files, starting with: %w",
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
2022-08-18 08:52:09 +02:00
len(removeErrors),
utilities.Join(removeErrors...),
)
}
return nil
}); err != nil {
return stats, err
}
Added abstract helper interface for all storage backends (#135) * Added abstract helper interface and implemented it for all storage backends * Moved storage client initializations also to helper classes * Fixed ssh init issue * Moved script parameter to helper struct to simplify script init. * Created sub modules. Enhanced abstract implementation. * Fixed config issue * Fixed declaration issues. Added config to interface. * Added StorageProviders to unify all backends. * Cleanup, optimizations, comments. * Applied discussed changes. See description. Moved modules to internal packages. Replaced StoragePool with slice. Moved conditional for init of storage backends back to script. * Fix docker build issue * Fixed accidentally removed local copy condition. * Delete .gitignore * Renaming/changes according to review Renamed Init functions and interface. Replaced config object with specific config values. Init func returns interface instead of struct. Removed custom import names where possible. * Fixed auto-complete error. * Combined copy instructions into one layer. * Added logging func for storages. * Introduced logging func for errors too. * Missed an error message * Moved config back to main. Optimized prune stats handling. * Move stats back to main package * Code doc stuff * Apply changes from #136 * Replace name field with function. * Changed receiver names from stg to b. * Renamed LogFuncDef to Log * Removed redundant package name. * Renamed storagePool to storages. * Simplified creation of new storage backend. * Added initialization for storage stats map. * Invert .dockerignore patterns. * Fix package typo
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return stats, nil
}
// copy creates a copy of the file located at `dst` at `src`.
func copyFile(src, dst string) error {
in, err := os.Open(src)
if err != nil {
return err
}
defer in.Close()
out, err := os.Create(dst)
if err != nil {
return err
}
_, err = io.Copy(out, in)
if err != nil {
out.Close()
return err
}
return out.Close()
}