You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 

71 lines
2.5 KiB

package replication
// === Phase 06: Storage and Control-Plane Adapter Interfaces ===
//
// These interfaces define the boundary between the engine replication core
// and external systems (storage backend, coordinator/control plane).
// The engine consumes these interfaces — it does not reach into storage
// or control-plane internals directly.
// StorageAdapter provides real retained-history and checkpoint state
// from the storage backend. The engine uses this to make recovery
// decisions grounded in actual data, not reconstructed test inputs.
type StorageAdapter interface {
// GetRetainedHistory returns the current WAL retention state.
// Must reflect actual TailLSN, HeadLSN, CommittedLSN, and checkpoint.
GetRetainedHistory() RetainedHistory
// PinSnapshot pins a checkpoint/base image at the given LSN for
// rebuild use. The snapshot must not be garbage-collected while pinned.
// Returns an error if no valid snapshot exists at that LSN.
PinSnapshot(checkpointLSN uint64) (SnapshotPin, error)
// ReleaseSnapshot releases a previously pinned snapshot.
ReleaseSnapshot(pin SnapshotPin)
// PinWALRetention holds WAL entries from startLSN to prevent reclaim.
// The engine calls this before starting catch-up to ensure the WAL
// tail does not advance past the required range.
PinWALRetention(startLSN uint64) (RetentionPin, error)
// ReleaseWALRetention releases a WAL retention hold.
ReleaseWALRetention(pin RetentionPin)
}
// SnapshotPin represents a held reference to a pinned snapshot/checkpoint.
type SnapshotPin struct {
LSN uint64
PinID uint64 // unique identifier for this pin
Valid bool
}
// RetentionPin represents a held reference to a WAL retention range.
type RetentionPin struct {
StartLSN uint64
PinID uint64
Valid bool
}
// ControlPlaneAdapter converts external assignment events into
// AssignmentIntent for the orchestrator.
type ControlPlaneAdapter interface {
// HandleHeartbeat processes a heartbeat from a volume server and
// returns any assignment updates that should be applied.
HandleHeartbeat(serverID string, volumes []VolumeHeartbeat) []AssignmentIntent
// HandleFailover processes a failover event and returns assignments
// for the affected replicas.
HandleFailover(deadServerID string) []AssignmentIntent
}
// VolumeHeartbeat represents one volume's state in a heartbeat.
type VolumeHeartbeat struct {
VolumeID string
ReplicaID string
Epoch uint64
FlushedLSN uint64
State string
DataAddr string
CtrlAddr string
AddrVersion uint64
}