feat(manager): add prefered time for backup

- enable the user to set a prerered hour for backup following this
  format 00h < xx < 23h

cmd/manager/manager.go

@@ -35,6 +35,7 @@ var (
 	parallelCount       int
 	refreshRate         string
 	backupInterval      string
+  backupTimeSpec      string
 )
 var envs = make(map[string]string)
 
@@ -59,7 +60,7 @@ var managerCmd = &cobra.Command{
 			agentImage = fmt.Sprintf("ghcr.io/camptocamp/bivac:%s", utils.ComputeDockerAgentImage(managerVersion))
 		}
 
-		err = manager.Start(bivacCmd.BuildInfo, o, server, volumesFilters, providersFile, targetURL, logServer, agentImage, retryCount, parallelCount, refreshRate, backupInterval)
+		err = manager.Start(bivacCmd.BuildInfo, o, server, volumesFilters, providersFile, targetURL, logServer, agentImage, retryCount, parallelCount, refreshRate, backupInterval, backupTimeSpec)
 		if err != nil {
 			log.Errorf("failed to start manager: %s", err)
 			return
@@ -139,6 +140,9 @@ func init() {
 	managerCmd.Flags().StringVarP(&backupInterval, "backup.interval", "", "23h", "Interval between two backups of a volume.")
 	envs["BIVAC_BACKUP_INTERVAL"] = "backup.interval"
 
+	managerCmd.Flags().StringVarP(&backupTimeSpec, "backup.time", "", "00h", "Prefer time to do the backup.")
+	envs["BIVAC_BACKUP_TIME"] = "backup.time"
+
 	bivacCmd.SetValuesFromEnv(envs, managerCmd.Flags())
 	bivacCmd.RootCmd.AddCommand(managerCmd)
 }

internal/manager/manager.go

@@ -34,7 +34,7 @@ type Manager struct {
 }
 
 // Start starts a Bivac manager which handle backups management
-func Start(buildInfo utils.BuildInfo, o orchestrators.Orchestrator, s Server, volumeFilters volume.Filters, providersFile, targetURL, logServer, agentImage string, retryCount, parallelCount int, refreshRate, backupInterval string) (err error) {
+func Start(buildInfo utils.BuildInfo, o orchestrators.Orchestrator, s Server, volumeFilters volume.Filters, providersFile, targetURL, logServer, agentImage string, retryCount, parallelCount int, refreshRate, backupInterval string, backupTimeSpec string) (err error) {
 	p, err := LoadProviders(providersFile)
 	if err != nil {
 		err = fmt.Errorf("failed to read providers file: %s", err)
@@ -47,6 +47,18 @@ func Start(buildInfo utils.BuildInfo, o orchestrators.Orchestrator, s Server, vo
 		return
 	}
 
+  //check backupTimeSpec format and constraint 00h < xxh < 23h e.g: 23h59m does not respect constraint
+  backupTime, err := time.ParseDuration(backupTimeSpec)
+	if err != nil {
+		err = fmt.Errorf("failed to parse backup prefered time: %s", err)
+		return
+	}
+
+  if backupTime.Hours() >= 23 && backupTime.Hours() >= 0 {
+		err = fmt.Errorf("backup prefered time does not respect constraint (00h < x < 23h): %s", err)
+		return
+	}
+
 	backupInt, err := time.ParseDuration(backupInterval)
 	if err != nil {
 		err = fmt.Errorf("failed to parse backup interval: %s", err)
@@ -90,7 +102,7 @@ func Start(buildInfo utils.BuildInfo, o orchestrators.Orchestrator, s Server, vo
 					delete(orphanAgents, val)
 				}
 
-				if !isBackupNeeded(v, backupInt) {
+				if !isBackupNeeded(v, backupInt, backupTime) {
 					continue
 				}
 
@@ -179,7 +191,7 @@ func Start(buildInfo utils.BuildInfo, o orchestrators.Orchestrator, s Server, vo
 	return
 }
 
-func isBackupNeeded(v *volume.Volume, backupInt time.Duration) bool {
+func isBackupNeeded(v *volume.Volume, backupInt time.Duration,backupTime time.Duration) bool {
 	if v.BackingUp {
 		return false
 	}
@@ -204,11 +216,17 @@ func isBackupNeeded(v *volume.Volume, backupInt time.Duration) bool {
 		return false
 	}
 
+  // retry if last backup status is Failed
 	if lbd.Add(time.Hour).Before(time.Now().UTC()) && v.LastBackupStatus == "Failed" {
 		return true
 	}
 
-	if lbd.Add(backupInt).Before(time.Now().UTC()) {
+  // Convertir targetBackupTime en une date avec le jour courant
+  now := time.Now()
+  targetBackupTime := time.Date(now.Year(), now.Month(), now.Day(),0,0,0,0,now.Location()).Add(backupTime)
+
+  // check backup interval and backup prefered time
+	if lbd.Add(backupInt).Before(time.Now().UTC()) && targetBackupTime.Before(now) {
 		return true
 	}
 	return false