From 5cd43dd4c9dd110aeb6d7cc71067927a0d56506b Mon Sep 17 00:00:00 2001
From: Matthew Penner <me@matthewp.io>
Date: Wed, 1 Sep 2021 09:54:41 -0600
Subject: [PATCH] archive: keep timestamps when extracting

---
 server/backup.go                |  8 ++++++--
 server/backup/backup.go         |  3 ++-
 server/backup/backup_local.go   |  2 +-
 server/backup/backup_s3.go      |  2 +-
 server/filesystem/compress.go   |  4 ++++
 server/filesystem/filesystem.go | 17 +++++++++++++++++
 6 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/server/backup.go b/server/backup.go
index acc8797..f511634 100644
--- a/server/backup.go
+++ b/server/backup.go
@@ -5,6 +5,7 @@ import (
 	"io/fs"
 	"io/ioutil"
 	"os"
+	"time"
 
 	"emperror.dev/errors"
 	"github.com/apex/log"
@@ -152,12 +153,15 @@ func (s *Server) RestoreBackup(b backup.BackupInterface, reader io.ReadCloser) (
 	// Attempt to restore the backup to the server by running through each entry
 	// in the file one at a time and writing them to the disk.
 	s.Log().Debug("starting file writing process for backup restoration")
-	err = b.Restore(s.Context(), reader, func(file string, r io.Reader, mode fs.FileMode) error {
+	err = b.Restore(s.Context(), reader, func(file string, r io.Reader, mode fs.FileMode, atime, mtime time.Time) error {
 		s.Events().Publish(DaemonMessageEvent, "(restoring): "+file)
 		if err := s.Filesystem().Writefile(file, r); err != nil {
 			return err
 		}
-		return s.Filesystem().Chmod(file, mode)
+		if err := s.Filesystem().Chmod(file, mode); err != nil {
+			return err
+		}
+		return s.Filesystem().Chtimes(file, atime, mtime)
 	})
 
 	return errors.WithStackIf(err)
diff --git a/server/backup/backup.go b/server/backup/backup.go
index e344ae2..496720e 100644
--- a/server/backup/backup.go
+++ b/server/backup/backup.go
@@ -8,6 +8,7 @@ import (
 	"io/fs"
 	"os"
 	"path"
+	"time"
 
 	"emperror.dev/errors"
 	"github.com/apex/log"
@@ -26,7 +27,7 @@ const (
 
 // RestoreCallback is a generic restoration callback that exists for both local
 // and remote backups allowing the files to be restored.
-type RestoreCallback func(file string, r io.Reader, mode fs.FileMode) error
+type RestoreCallback func(file string, r io.Reader, mode fs.FileMode, atime, mtime time.Time) error
 
 // noinspection GoNameStartsWithPackageName
 type BackupInterface interface {
diff --git a/server/backup/backup_local.go b/server/backup/backup_local.go
index 61dc164..c652b13 100644
--- a/server/backup/backup_local.go
+++ b/server/backup/backup_local.go
@@ -88,7 +88,7 @@ func (b *LocalBackup) Restore(ctx context.Context, _ io.Reader, callback Restore
 			if f.IsDir() {
 				return nil
 			}
-			return callback(filesystem.ExtractNameFromArchive(f), f, f.Mode())
+			return callback(filesystem.ExtractNameFromArchive(f), f, f.Mode(), f.ModTime(), f.ModTime())
 		}
 	})
 }
diff --git a/server/backup/backup_s3.go b/server/backup/backup_s3.go
index e240b5e..85faa59 100644
--- a/server/backup/backup_s3.go
+++ b/server/backup/backup_s3.go
@@ -116,7 +116,7 @@ func (s *S3Backup) Restore(ctx context.Context, r io.Reader, callback RestoreCal
 			return err
 		}
 		if header.Typeflag == tar.TypeReg {
-			if err := callback(header.Name, tr, header.FileInfo().Mode()); err != nil {
+			if err := callback(header.Name, tr, header.FileInfo().Mode(), header.AccessTime, header.ModTime); err != nil {
 				return err
 			}
 		}
diff --git a/server/filesystem/compress.go b/server/filesystem/compress.go
index 5227512..cabbfdd 100644
--- a/server/filesystem/compress.go
+++ b/server/filesystem/compress.go
@@ -136,6 +136,10 @@ func (fs *Filesystem) DecompressFile(dir string, file string) error {
 		if err := fs.Chmod(p, f.Mode()); err != nil {
 			return wrapError(err, source)
 		}
+		// Update the file modification time to the one set in the archive.
+		if err := fs.Chtimes(p, f.ModTime(), f.ModTime()); err != nil {
+			return wrapError(err, source)
+		}
 		return nil
 	})
 	if err != nil {
diff --git a/server/filesystem/filesystem.go b/server/filesystem/filesystem.go
index 4f04d9a..b507709 100644
--- a/server/filesystem/filesystem.go
+++ b/server/filesystem/filesystem.go
@@ -528,3 +528,20 @@ func (fs *Filesystem) ListDirectory(p string) ([]Stat, error) {
 
 	return out, nil
 }
+
+func (fs *Filesystem) Chtimes(path string, atime, mtime time.Time) error {
+	cleaned, err := fs.SafePath(path)
+	if err != nil {
+		return err
+	}
+
+	if fs.isTest {
+		return nil
+	}
+
+	if err := os.Chtimes(cleaned, atime, mtime); err != nil {
+		return err
+	}
+
+	return nil
+}