package local¶

import "github.com/cloudboss/unobin/pkg/state/local"

Package local stores state snapshots on the local filesystem.

The Backend interface and Snapshot types live in pkg/sdk/state so provider libraries can implement their own backends without depending on unobin core. The fixed set an operator selects from lives in pkg/backends.

Types¶

type Store¶

type Store struct {
    Root    string
    Factory string
    // contains filtered or unexported fields
}

Store reads and writes snapshots under a per-stack directory. Layout is as follows:

<Root>/<Factory>/<Stack>/
  current             // File containing the SHA of the current snapshot.
  snapshots/
    <rev>.json.enc    // rev is an RFC3339Nano timestamp
    ...

func NewStore¶

func NewStore(
    root, factory, stack string,
    enc sdkencrypt.Encrypter,
) (*Store, error)

NewStore returns a Store for the given factory and stack under root, creating the directory tree if it doesn't exist. The Encrypter is required, but a pass-through (encrypters.Noop) can be passed for tests.

func (*Store) Current¶

func (s *Store) Current() (*sdkstate.Snapshot, error)

Current returns the snapshot named by the current pointer. Returns sdkstate.ErrNoCurrent when no snapshot has been written yet.

func (*Store) CurrentRev¶

func (s *Store) CurrentRev() (string, error)

CurrentRev returns the rev the current pointer names, or sdkstate.ErrNoCurrent.

func (*Store) Delete¶

func (s *Store) Delete(rev string) error

Delete removes the snapshot with the given rev. Removing a rev that does not exist is not an error.

func (*Store) ForceUnlock¶

func (s *Store) ForceUnlock() error

ForceUnlock removes the lock marker without checking who holds it. Operators run this to recover after a leaked lock and must ensure no concurrent run is in progress.

func (*Store) Get¶

func (s *Store) Get(rev string) (*sdkstate.Snapshot, error)

Get returns the snapshot with the given rev.

func (*Store) List¶

func (s *Store) List() ([]string, error)

List returns the revs of every stored snapshot in chronological order.

func (*Store) Lock¶

func (s *Store) Lock(ctx context.Context) (sdkstate.Lock, error)

Lock acquires the stack's exclusive lock by creating a marker file under the stack directory. Lock blocks until the marker can be created or ctx is canceled. The marker file holds the holder's pid so an operator can identify a stuck lock.

func (*Store) SetCurrent¶

func (s *Store) SetCurrent(rev string) error

SetCurrent atomically points "current" at the named rev. The snapshot must already exist.

func (*Store) Stack¶

func (s *Store) Stack() string

Stack returns the stack name this store was constructed for. Required by the Backend interface.

func (*Store) Write¶

func (s *Store) Write(snap *sdkstate.Snapshot) (string, error)

Write commits snap to disk and returns its rev. The caller advances the current pointer with SetCurrent. Each rev starts as an RFC3339Nano timestamp; if a snapshot already exists at that path (because two writes share the same nanosecond), a numeric suffix is appended until the path is fresh, so uniqueness does not depend on the clock advancing between writes.