shard_state.go

package dagstore

type ShardState byte

const (
	// ShardStateNew indicates that a shard has just been registered and is
	// about to be processed for activation.
	ShardStateNew ShardState = iota

	// ShardStateInitializing indicates that the shard is being initialized
	// by being fetched from the mount and being indexed.
	ShardStateInitializing

	// ShardStateAvailable indicates that the shard has been initialized and is
	// active for serving queries. There are no active shard readers.
	ShardStateAvailable

	// ShardStateServing indicates the shard has active readers and thus is
	// currently actively serving requests.
	ShardStateServing

	// ShardStateRecovering indicates that the shard is recovering from an
	// errored state. Such recoveries are always initiated by the user through
	// DAGStore.RecoverShard().
	ShardStateRecovering ShardState = 0x80

	// ShardStateErrored indicates that an unexpected error was encountered
	// during a shard operation, and therefore the shard needs to be recovered.
	ShardStateErrored ShardState = 0xf0

	// ShardStateUnknown indicates that it's not possible to determine the state
	// of the shard. This state is currently unused, but it's reserved.
	ShardStateUnknown ShardState = 0xff
)

func (ss ShardState) String() string {
	strs := [...]string{
		ShardStateNew:          "ShardStateNew",
		ShardStateInitializing: "ShardStateInitializing",
		ShardStateAvailable:    "ShardStateAvailable",
		ShardStateServing:      "ShardStateServing",
		ShardStateRecovering:   "ShardStateRecovering",
		ShardStateErrored:      "ShardStateErrored",
		ShardStateUnknown:      "ShardStateUnknown",
	}
	if ss < 0 || int(ss) >= len(strs) {
		// safety comes first.
		return "__undefined__"
	}
	return strs[ss]
}