Project: Velero (Runtime / Cloud Native Storage)
File: schedule-skip-immediately-config_design.md

When unpausing schedule, a backup could be due immediately. New Schedules also create new backup immediately. This design allows user to skip immediately due backup run upon unpausing or schedule creation. Currently, the default behavior of schedule when `.Status.LastBackup` is nil or is due immediately after unpausing, a backup will be created. This may not be a desired by all users (https://github.com/vmware-tanzu/velero/issues/6517) User want ability to skip the first immediately due backup when schedule is unpaused and or created. If you create a schedule with cron "45 " and pause it at say the 43rd minute and then unpause it at say 50th minute, a backup gets triggered (since .Status.LastBackup is nil or >60min ago). With this design, user can skip the first immediately due backup when schedule is unpaused and or created. Add an option so user can when unpausing (when immediately due) or creating new schedule, to not create a backup immediately. Changing the default behavior Add a new field with to the schedule spec and as a new cli flags for install, server, schedule commands; allowing user to skip immediately due backup when unpausing or schedule creation. If CLI flag is specified during schedule unpause, velero will update the schedule spec accordingly and override prior spec for `skipImmediately``. `velero schedule unpause` will now take an optional bool flag `--skip-immediately` to allow user to override the behavior configured for velero server (see `velero server` below). `velero schedule unpause schedule-1 --skip-immediately=false` will unpause the schedule but not skip the backup if due immediately from `Schedule.Status.LastBackup` timestamp. Backup will be run at the next cron schedule. `velero schedule unpause schedule-1 --skip-immediately=true` will unpause the schedule and skip the backup if due immediately from `Schedule.Status.LastBackup` timestamp. Backup will also be run at the next cron schedule. `velero schedule unpause schedule-1` will check `.spec.SkipImmediately` in the schedule to determine behavior. This field will default to false to maintain prior behavior. `velero server` will add a new flag `--schedule-skip-immediately` to configure default value to patch new schedules created without the field. This flag will default to false to maintain prior behavior if not set. `velero install` will add a new flag `--schedule-skip-immediately` to configure default value to patch new schedules created without the field. This flag will default to false to maintain prior behavior if not set. `pkg/apis/velero/v1/schedule_types.go` ```diff // ScheduleSpec defines the specification for a Velero schedule type ScheduleSpec struct { // Template is the definition of the Backup to be run // on the provided schedule Template BackupSpec `json:"template"` // Schedule is a Cron expression defining when to run // the

Schedule string `json:"schedule"` // UseOwnerReferencesBackup specifies whether to use // OwnerReferences on backups created by this Schedule. // +optional // +nullable UseOwnerReferencesInBackup *bool `json:"useOwnerReferencesInBackup,omitempty"` // Paused specifies whether the schedule is paused or not // +optional Paused bool `json:"paused,omitempty"` // SkipImmediately specifies whether to skip backup if schedule is due immediately from `Schedule.Status.LastBackup` timestamp when schedule is unpaused or if schedule is new. // If true, backup will be skipped immediately when schedule is unpaused if it is due based on .Status.LastBackupTimestamp or schedule is new, and will run at next schedule time. // If false, backup will not be skipped immediately when schedule is unpaused, but will run at next schedule time. // If empty, will follow server configuration (default: false). // +optional SkipImmediately bool `json:"skipImmediately,omitempty"` } ``` `LastSkipped` will be added to `ScheduleStatus` struct to track the last time a schedule was skipped. ```diff // ScheduleStatus captures the current state of a Velero schedule type ScheduleStatus struct { // Phase is the current phase of the Schedule // +optional Phase SchedulePhase `json:"phase,omitempty"` // LastBackup is the last time a Backup was run for this // Schedule schedule // +optional // +nullable LastBackup *metav1.Time `json:"lastBackup,omitempty"` // LastSkipped is the last time a Schedule was skipped // +optional // +nullable LastSkipped *metav1.Time `json:"lastSkipped,omitempty"` // ValidationErrors is a slice of all validation errors (if // applicable) // +optional ValidationErrors []string `json:"validationErrors,omitempty"` } ``` When `schedule.spec.SkipImmediately` is `true`, `LastSkipped` will be set to the current time, and `schedule.spec.SkipImmediately` set to nil so it can be used again. The `getNextRunTime()` function below is updated so `LastSkipped` which is after `LastBackup` will be used to determine next run time. ```go func getNextRunTime(schedule *velerov1.Schedule, cronSchedule cron.Schedule, asOf time.Time) (bool, time.Time) { var lastBackupTime time.Time if schedule.Status.LastBackup != nil { lastBackupTime = schedule.Status.LastBackup.Time } else { lastBackupTime = schedule.CreationTimestamp.Time } if schedule.Status.LastSkipped != nil && schedule.Status.LastSkipped.After(lastBackupTime) { lastBackupTime = schedule.Status.LastSkipped.Time } nextRunTime := cronSchedule.Next(lastBackupTime) return asOf.After(nextRunTime), nextRunTime } ``` When schedule is unpaused, and `Schedule.Status.LastBackup` is not nil, if `Schedule.Status.LastSkipped` is recent, a backup will not be created. When schedule is unpaused or created with `Schedule.Status.LastBackup` set to nil or schedule is newly created, normally a backup will be created immediately. If `Schedule.Status.LastSkipped` is recent, a backup will not be created. Backup will be run at the next cron schedule based on LastBackup or LastSkipped whichever is more recent. N/A None Upon upgrade, the new field will be added to the schedule spec automatically and will default to the prior behavior of running a backup when schedule is unpaused if it is due based on .Status.LastBackup or schedule is new. Since this is a new field, it will be ignored by older versions of velero. TBD N/A