consul/vendor/github.com/hashicorp/raft/log.go

61 lines
1.5 KiB
Go

package raft
// LogType describes various types of log entries.
type LogType uint8
const (
// LogCommand is applied to a user FSM.
LogCommand LogType = iota
// LogNoop is used to assert leadership.
LogNoop
// LogAddPeer is used to add a new peer.
LogAddPeer
// LogRemovePeer is used to remove an existing peer.
LogRemovePeer
// LogBarrier is used to ensure all preceding operations have been
// applied to the FSM. It is similar to LogNoop, but instead of returning
// once committed, it only returns once the FSM manager acks it. Otherwise
// it is possible there are operations committed but not yet applied to
// the FSM.
LogBarrier
)
// Log entries are replicated to all members of the Raft cluster
// and form the heart of the replicated state machine.
type Log struct {
Index uint64
Term uint64
Type LogType
Data []byte
// peer is not exported since it is not transmitted, only used
// internally to construct the Data field.
peer string
}
// LogStore is used to provide an interface for storing
// and retrieving logs in a durable fashion.
type LogStore interface {
// Returns the first index written. 0 for no entries.
FirstIndex() (uint64, error)
// Returns the last index written. 0 for no entries.
LastIndex() (uint64, error)
// Gets a log entry at a given index.
GetLog(index uint64, log *Log) error
// Stores a log entry.
StoreLog(log *Log) error
// Stores multiple log entries.
StoreLogs(logs []*Log) error
// Deletes a range of log entries. The range is inclusive.
DeleteRange(min, max uint64) error
}