orcraft

Documentation

Index

• Constants
• Variables
• func AsyncSnapshot() error
• func FatalRaftError(err error) error
• func GetLeader() string
• func GetPeers() ([]string, error)
• func GetState() raft.RaftState
• func HttpGet(peer string, path string) ([]byte, error)
• func IsLeader() bool
• func IsPartOfQuorum() bool
• func IsPeer(peer string) (bool, error)
• func IsRaftEnabled() bool
• func Monitor()
• func PublishCommand(op string, value interface{}) (response interface{}, err error)
• func PublishYield(toPeer string) (response interface{}, err error)
• func PublishYieldHostnameHint(hostnameHint string) (response interface{}, err error)
• func QuorumSize() (int, error)
• func Setup(applier CommandApplier, snapshotCreatorApplier SnapshotCreatorApplier, ...) error
• func Snapshot() error
• func StepDown()
• func Yield() error
• type CommandApplier
• type FileSnapshotSink
  • func (s *FileSnapshotSink) Cancel() error
  • func (s *FileSnapshotSink) Close() error
  • func (s *FileSnapshotSink) ID() string
  • func (s *FileSnapshotSink) Write(b []byte) (int, error)
• type FileSnapshotStore
  • func NewFileSnapshotStore(base string, retain int, logOutput io.Writer) (*FileSnapshotStore, error)
  • func NewFileSnapshotStoreWithLogger(base string, retain int, logger *log.Logger) (*FileSnapshotStore, error)
  • func (f *FileSnapshotStore) Create(index, term uint64, peers []byte) (raft.SnapshotSink, error)
  • func (f *FileSnapshotStore) List() ([]*raft.SnapshotMeta, error)
  • func (f *FileSnapshotStore) Open(id string) (*raft.SnapshotMeta, io.ReadCloser, error)
  • func (f *FileSnapshotStore) ReapSnapshots(currentSnapshotMeta *fileSnapshotMeta) error
• type RelationalStore
  • func NewRelationalStore(dataDir string) *RelationalStore
  • func (relStore *RelationalStore) DeleteAll() error
  • func (relStore *RelationalStore) DeleteRange(min, max uint64) error
  • func (relStore *RelationalStore) FirstIndex() (idx uint64, err error)
  • func (relStore *RelationalStore) Get(key []byte) (val []byte, err error)
  • func (relStore *RelationalStore) GetLog(index uint64, log *raft.Log) error
  • func (relStore *RelationalStore) GetUint64(key []byte) (uint64, error)
  • func (relStore *RelationalStore) LastIndex() (idx uint64, err error)
  • func (relStore *RelationalStore) Set(key []byte, val []byte) error
  • func (relStore *RelationalStore) SetUint64(key []byte, val uint64) error
  • func (relStore *RelationalStore) StoreLog(log *raft.Log) error
  • func (relStore *RelationalStore) StoreLogs(logs []*raft.Log) error
• type SnapshotCreatorApplier
• type Store
  • func NewStore(raftDir string, raftBind string, raftAdvertise string, applier CommandApplier, ...) *Store
  • func (store *Store) Join(addr string) error
  • func (store *Store) Open(peerNodes []string) error

Constants

const (
	YieldCommand     = "yield"
	YieldHintCommand = "yield-hint"
)

Variables

var RaftNotRunning = fmt.Errorf("raft is not configured/running")

var ThisHostname string

Functions

func AsyncSnapshot

func AsyncSnapshot() error

func FatalRaftError

func FatalRaftError(err error) error

func GetLeader

func GetLeader() string

GetLeader returns identity of raft leader

func GetPeers

func GetPeers() ([]string, error)

func GetState

func GetState() raft.RaftState

GetState returns current raft state

func HttpGet

func HttpGet(peer string, path string) ([]byte, error)

readResponse returns the body of an HTTP response

func IsLeader

func IsLeader() bool

IsLeader tells if this node is the current raft leader

func IsPartOfQuorum

func IsPartOfQuorum() bool

IsPartOfQuorum returns `true` when this node is part of the raft quorum, meaning its data and opinion are trustworthy. Comapre that to a node which has left (or has not yet joined) the quorum: it has stale data.

func IsPeer

func IsPeer(peer string) (bool, error)

func IsRaftEnabled

func IsRaftEnabled() bool

func Monitor

func Monitor()

Monitor is a utility function to routinely observe leadership state. It doesn't actually do much; merely takes notes.

func PublishCommand

func PublishCommand(op string, value interface{}) (response interface{}, err error)

PublishCommand will distribute a command across the group

func PublishYield

func PublishYield(toPeer string) (response interface{}, err error)

func PublishYieldHostnameHint

func PublishYieldHostnameHint(hostnameHint string) (response interface{}, err error)

func QuorumSize

func QuorumSize() (int, error)

func Setup

func Setup(applier CommandApplier, snapshotCreatorApplier SnapshotCreatorApplier, thisHostname string) error

Setup creates the entire raft shananga. Creates the store, associates with the throttler, contacts peer nodes, and subscribes to leader changes to export them.

func Snapshot

func Snapshot() error

func StepDown

func StepDown()

func Yield

func Yield() error

Types

type CommandApplier

type CommandApplier interface {
	ApplyCommand(op string, value []byte) interface{}
}

type FileSnapshotSink

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

FileSnapshotSink implements SnapshotSink with a file.

func (*FileSnapshotSink) Cancel

func (s *FileSnapshotSink) Cancel() error

Cancel is used to indicate an unsuccessful end.

func (*FileSnapshotSink) Close

func (s *FileSnapshotSink) Close() error

Close is used to indicate a successful end.

func (*FileSnapshotSink) ID

func (s *FileSnapshotSink) ID() string

ID returns the ID of the snapshot, can be used with Open() after the snapshot is finalized.

func (*FileSnapshotSink) Write

func (s *FileSnapshotSink) Write(b []byte) (int, error)

Write is used to append to the state file. We write to the buffered IO object to reduce the amount of context switches.

type FileSnapshotStore

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

FileSnapshotStore implements the SnapshotStore interface and allows snapshots to be made on the local disk.

func NewFileSnapshotStore

func NewFileSnapshotStore(base string, retain int, logOutput io.Writer) (*FileSnapshotStore, error)

NewFileSnapshotStore creates a new FileSnapshotStore based on a base directory. The `retain` parameter controls how many snapshots are retained. Must be at least 1.

func NewFileSnapshotStoreWithLogger

func NewFileSnapshotStoreWithLogger(base string, retain int, logger *log.Logger) (*FileSnapshotStore, error)

NewFileSnapshotStoreWithLogger creates a new FileSnapshotStore based on a base directory. The `retain` parameter controls how many snapshots are retained. Must be at least 1.

func (*FileSnapshotStore) Create

func (f *FileSnapshotStore) Create(index, term uint64, peers []byte) (raft.SnapshotSink, error)

Create is used to start a new snapshot

func (*FileSnapshotStore) List

func (f *FileSnapshotStore) List() ([]*raft.SnapshotMeta, error)

List returns available snapshots in the store.

func (*FileSnapshotStore) Open

func (f *FileSnapshotStore) Open(id string) (*raft.SnapshotMeta, io.ReadCloser, error)

Open takes a snapshot ID and returns a ReadCloser for that snapshot.

func (*FileSnapshotStore) ReapSnapshots

func (f *FileSnapshotStore) ReapSnapshots(currentSnapshotMeta *fileSnapshotMeta) error

ReapSnapshots reaps any snapshots beyond the retain count.

type RelationalStore

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

RelationalStoreimplements: - hashicorp/raft.StableStore - hashicorp/log.LogStore

func NewRelationalStore

func NewRelationalStore(dataDir string) *RelationalStore

func (*RelationalStore) DeleteAll

func (relStore *RelationalStore) DeleteAll() error

func (*RelationalStore) DeleteRange

func (relStore *RelationalStore) DeleteRange(min, max uint64) error

DeleteRange deletes a range of log entries. The range is inclusive.

func (*RelationalStore) FirstIndex

func (relStore *RelationalStore) FirstIndex() (idx uint64, err error)

func (*RelationalStore) Get

func (relStore *RelationalStore) Get(key []byte) (val []byte, err error)

Get returns the value for key, or an empty byte slice if key was not found.

func (*RelationalStore) GetLog

func (relStore *RelationalStore) GetLog(index uint64, log *raft.Log) error

GetLog gets a log entry at a given index.

func (*RelationalStore) GetUint64

func (relStore *RelationalStore) GetUint64(key []byte) (uint64, error)

GetUint64 returns the uint64 value for key, or 0 if key was not found.

func (*RelationalStore) LastIndex

func (relStore *RelationalStore) LastIndex() (idx uint64, err error)

LastIndex returns the last index written. 0 for no entries.

func (*RelationalStore) Set

func (relStore *RelationalStore) Set(key []byte, val []byte) error

func (*RelationalStore) SetUint64

func (relStore *RelationalStore) SetUint64(key []byte, val uint64) error

func (*RelationalStore) StoreLog

func (relStore *RelationalStore) StoreLog(log *raft.Log) error

StoreLog stores a log entry.

func (*RelationalStore) StoreLogs

func (relStore *RelationalStore) StoreLogs(logs []*raft.Log) error

StoreLogs stores multiple log entries.

type SnapshotCreatorApplier

type SnapshotCreatorApplier interface {
	GetData() (data []byte, err error)
	Restore(rc io.ReadCloser) error
}

type Store

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

func NewStore

func NewStore(raftDir string, raftBind string, raftAdvertise string, applier CommandApplier, snapshotCreatorApplier SnapshotCreatorApplier) *Store

NewStore inits and returns a new store

func (*Store) Join

func (store *Store) Join(addr string) error

Join joins a node, located at addr, to this store. The node must be ready to respond to Raft communications at that address.

func (*Store) Open

func (store *Store) Open(peerNodes []string) error

Open opens the store. If enableSingle is set, and there are no existing peers, then this node becomes the first node, and therefore leader, of the cluster.