fix: 修复备份工具的多处问题

- go.mod: 将非法版本号 go 1.26.4 改为 go 1.26
- engine: 压缩失败时删除残留的半截 tar.gz 文件
- config: 支持仅按天数保留(count 和 days 均未设时才用默认 count=7)
- engine: docker compose stop 失败时也尝试重启,避免容器停摆
- list: 仅显示真正的备份归档文件(新增导出 IsBackupArchive)
- systemd: 移除 PrivateTmp,暂存目录改到安装目录内,避免私有 /tmp 被大目录撑爆

README.md

@@ -54,13 +54,13 @@ sudo mkdir -p /opt/docker-compose-backup
 sudo cp docker-compose-backup-linux-arm64 /opt/docker-compose-backup/docker-compose-backup
 sudo chmod +x /opt/docker-compose-backup/docker-compose-backup
 sudo cp config.yaml /opt/docker-compose-backup/config.yaml
-sudo mkdir -p /opt/docker-compose-backup/backups
+sudo mkdir -p /opt/docker-compose-backup/backups /opt/docker-compose-backup/tmp
 sudo cp docker-compose-backup.service /etc/systemd/system/
 sudo systemctl daemon-reload
 sudo systemctl enable --now docker-compose-backup
 ```
 
-The example config uses `/opt/docker-compose-backup/backups`, which is allowed by the service sandbox.
+The example config uses `/opt/docker-compose-backup/backups`, which is allowed by the service sandbox. The unit's `ReadWritePaths` covers the whole install dir, so set `global.temp_dir` to a subdirectory there (e.g. `/opt/docker-compose-backup/tmp`). The unit intentionally does **not** enable `PrivateTmp`, since a private `/tmp` is often small and would be exhausted when copying large project directories.
 
 ## Configuration
 
@@ -69,7 +69,7 @@ See [config.example.yaml](config.example.yaml) for a full annotated example.
 ```yaml
 global:
   backup_dir: /opt/docker-compose-backup/backups
-  temp_dir: /tmp/docker-backup       # optional, defaults to OS temp
+  temp_dir: /opt/docker-compose-backup/tmp  # optional, defaults to OS temp
 
 projects:
   - name: myapp

cmd/backup/list.go

@@ -56,7 +56,7 @@ func runList(cmd *cobra.Command, args []string) error {
 
 		var backups []string
 		for _, e := range entries {
-			if !e.IsDir() {
+			if !e.IsDir() && backup.IsBackupArchive(proj.Name, e.Name()) {
 				backups = append(backups, e.Name())
 			}
 		}

config.example.yaml

@@ -1,7 +1,10 @@
 # docker-compose-backup example configuration
 global:
   backup_dir: /opt/docker-compose-backup/backups
-  # temp_dir: /tmp/docker-compose-backup  # defaults to OS temp dir
+  # Staging area for the pre-compression copy. Defaults to the OS temp dir.
+  # Under the bundled systemd unit, set this inside the install dir so it stays
+  # within the sandbox's writable path (the unit no longer uses PrivateTmp).
+  temp_dir: /opt/docker-compose-backup/tmp
 
 projects:
   - name: myapp

docker-compose-backup.service

@@ -19,8 +19,11 @@ User=root
 NoNewPrivileges=yes
 ProtectSystem=strict
 ProtectHome=yes
-ReadWritePaths=/opt/docker-compose-backup /tmp
+# The backup copies whole project directories into a staging area before
-PrivateTmp=yes
+# compressing. Keep staging inside the writable install dir (see temp_dir in
+# config.yaml) rather than /tmp, and do NOT use PrivateTmp — a private /tmp is
+# often small/tmpfs-backed and can be exhausted by large project copies.
+ReadWritePaths=/opt/docker-compose-backup
 ProtectKernelTunables=yes
 ProtectKernelModules=yes
 ProtectControlGroups=yes

go.mod

@@ -1,6 +1,6 @@
 module git.misaka.ren/M1saka/docker_backup
 
-go 1.26.4
+go 1.26
 
 require (
 	github.com/aws/aws-sdk-go-v2 v1.42.1

internal/backup/engine.go

@@ -83,9 +83,12 @@ func (e *Engine) backupOne(ctx context.Context, proj config.ProjectConfig) Resul
 
 	executor := NewComposeExecutor(proj.Path, proj.ComposeFile)
 
-	// 1. Stop the compose project.
+	// 1. Stop the compose project. If the stop is interrupted midway
+	// (e.g. the context is cancelled), containers may be left stopped, so
+	// always attempt a restart before returning.
 	stopStart := time.Now()
 	if err := executor.Stop(ctx); err != nil {
+		_ = restartCompose(executor)
 		result.Error = fmt.Errorf("stop: %w", err)
 		result.Duration = time.Since(start)
 		return result
@@ -226,9 +229,14 @@ func createTarGz(ctx context.Context, srcDir, dstPath string) error {
 
 	closeErr := closeTarGz(tw, gw, f)
 	if walkErr != nil {
+		_ = os.Remove(dstPath)
 		return walkErr
 	}
-	return closeErr
+	if closeErr != nil {
+		_ = os.Remove(dstPath)
+		return closeErr
+	}
+	return nil
 }
 
 func closeTarGz(tw *tar.Writer, gw *gzip.Writer, f *os.File) error {

internal/backup/retention.go

@@ -87,5 +87,10 @@ func ApplyRetention(backupDir, projectName string, policy RetentionPolicy) (int,
 }
 
 func isBackupArchive(projectName, name string) bool {
+	return IsBackupArchive(projectName, name)
+}
+
+// IsBackupArchive reports whether name is a backup archive for the project.
+func IsBackupArchive(projectName, name string) bool {
 	return strings.HasPrefix(name, projectName+"-") && strings.HasSuffix(name, ".tar.gz")
 }

internal/config/config.go

@@ -85,7 +85,9 @@ func (c *Config) Validate() error {
 		if p.ComposeFile == "" {
 			p.ComposeFile = "docker-compose.yml"
 		}
-		if p.Retention.Count <= 0 {
+		// Apply the default count only when no retention policy is set at all.
+		// This lets a user configure days-only retention (count omitted).
+		if p.Retention.Count <= 0 && p.Retention.Days <= 0 {
 			p.Retention.Count = DefaultRetentionCount
 		}
 	}

internal/config/config_test.go

@@ -45,6 +45,34 @@ projects:
 	}
 }
 
+func TestLoadDaysOnlyRetention(t *testing.T) {
+	yaml := `
+global:
+  backup_dir: /tmp/backups
+projects:
+  - name: testapp
+    path: /opt/testapp
+    retention:
+      days: 30
+`
+	dir := t.TempDir()
+	path := filepath.Join(dir, "config.yaml")
+	if err := os.WriteFile(path, []byte(yaml), 0644); err != nil {
+		t.Fatal(err)
+	}
+	cfg, err := Load(path)
+	if err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+	p := cfg.Projects[0]
+	if p.Retention.Count != 0 {
+		t.Errorf("count should stay 0 for days-only retention, got %d", p.Retention.Count)
+	}
+	if p.Retention.Days != 30 {
+		t.Errorf("days = %d", p.Retention.Days)
+	}
+}
+
 func TestLoadMissingBackupDir(t *testing.T) {
 	yaml := `
 projects: