Documentation
¶
Overview ¶
Package gc deletes backup chains by retention rules and cleans up dangling archives. It is the only destructive operation on a backup storage, so every run first builds a plan that can be inspected (tt backup gc --dry-run) and only then executes it.
Index ¶
Constants ¶
const DefaultOrphanAge = 24 * time.Hour
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Backup ¶
type Backup struct {
// BackupID identifies the backup.
BackupID string `json:"backup_id"`
// ManifestKey is deleted first: a manifest without archives breaks recovery
// loudly, archives without a manifest are collected by the next run.
ManifestKey string `json:"manifest_key"`
// ArchiveKeys are the archives the manifest referred to, sorted by key.
ArchiveKeys []string `json:"archive_keys"`
}
Backup is one backup scheduled for deletion.
type Options ¶
type Options struct {
// KeepFull keeps the last N healthy backup chains; 0 means the rule is unset.
KeepFull int
// KeepDays keeps backups created within the last N days; 0 means unset.
KeepDays int
// OrphanAge is the minimum age of a dangling archive eligible for deletion.
OrphanAge time.Duration
// Now is the reference time for age rules; zero means time.Now().
Now time.Time
}
Options are the retention rules of one gc run.
type Orphan ¶
type Orphan struct {
// Key is the storage key of the archive.
Key string `json:"key"`
// LastModified is when the storage last wrote the archive.
LastModified time.Time `json:"last_modified"`
}
Orphan is a dangling archive scheduled for deletion.
type Plan ¶
type Plan struct {
// Backups are ordered group by group, newest backup of a group first.
Backups []Backup `json:"backups"`
// Orphans are dangling archives, sorted by key.
Orphans []Orphan `json:"orphans"`
// Notes explain what the run deliberately left alone.
Notes []string `json:"notes"`
}
Plan is everything one gc run would delete, in deletion order.
func BuildPlan ¶
BuildPlan works out what a gc run with these options would delete. It only reads the storage.
type Result ¶
type Result struct {
// Backups is the number of backups whose manifest was deleted.
Backups int `json:"backups_deleted"`
// Archives is the number of archives deleted together with their backup.
Archives int `json:"archives_deleted"`
// Orphans is the number of dangling archives deleted.
Orphans int `json:"orphans_deleted"`
// Kept lists dangling archives that were skipped after a second look.
Kept []string `json:"orphans_kept"`
}
Result is what a gc run actually deleted. Deleting a key that does not exist is a success on every backend, so the counts can only be as honest as the plan: BuildPlan keeps out of it the keys the storage does not hold, and this is the one number that tells an operator a destructive run did what it said.
func Execute ¶
Execute deletes what the plan describes. Backups go first and, inside one backup, the manifest goes before its archives, so that an interrupted run leaves collectable garbage instead of a manifest pointing at nothing: the archives left behind are collected once they are older than --orphan-age.
Source Files