revision

type Draft struct {
	ParentID int64
	Payload  []byte
	Author   string
	Comment  string
}

type Getter interface {
	Get(ctx context.Context, id int64) (Revision, error)
}

type MemoryStore struct {
	// contains filtered or unexported fields
}

type Meta struct {
	Author  string
	Comment string
}

type Revision struct {
	ID          int64
	ParentID    int64
	ContentHash string
	Payload     []byte
	State       State
	Author      string
	Comment     string
	CreatedAt   time.Time
	PublishedAt time.Time
}

type State string

type Store interface {
	// Create writes a new draft and returns it with its ID and hash.
	Create(ctx context.Context, d Draft) (Revision, error)
	// Get returns one revision with its payload.
	Get(ctx context.Context, id int64) (Revision, error)
	// List returns revision summaries, newest first; limit <= 0 means all.
	List(ctx context.Context, limit int) ([]Revision, error)
	// Published returns the published revision, or ErrNoPublished.
	Published(ctx context.Context) (Revision, error)
	// Publish publishes draft id. expectedCurrent is the caller's view of the
	// published ID (0 for none); a mismatch fails with ErrConflict.
	Publish(ctx context.Context, id, expectedCurrent int64, m Meta) (Revision, error)
	// Rollback marks the published revision rolled-back and publishes a new
	// revision copying target's payload. Target 0 selects the newest
	// superseded revision whose content differs from the published one.
	Rollback(ctx context.Context, expectedCurrent, target int64, m Meta) (Revision, error)
	// Discard marks draft id discarded: it stays in the history and is never
	// published. A revision that is not a draft fails with ErrInvalidState.
	Discard(ctx context.Context, id int64) (Revision, error)
	// ImportHistory copies revisions verbatim into an empty store, keeping
	// IDs, states, authors and timestamps. It is used by migrate --history.
	ImportHistory(ctx context.Context, revs []Revision) error
	// Sequence grows with every write (a revision created, published,
	// rolled back or discarded, history imported), as every process sharing
	// the store sees it: a reader learns that revisions changed, a discard
	// of an old draft included, by comparing two readings. It may also grow
	// without a change to revisions.
	Sequence(ctx context.Context) (int64, error)
	Close() error
}