consensus

package
v0.24.0-rc0 Latest Latest
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This package is not in the latest version of its module.

 Go to latest Published: Sep 5, 2018 License: Apache-2.0 Imports: 40 Imported by: 0

README

See the consensus spec and the reactor consensus spec for more information.

Documentation

Index

Constants

View Source 
const (
	StateChannel       = byte(0x20)
	DataChannel        = byte(0x21)
	VoteChannel        = byte(0x22)
	VoteSetBitsChannel = byte(0x23)
)

Variables

View Source 
var (
	ErrPeerStateHeightRegression = errors.New("Error peer state height regression")
	ErrPeerStateInvalidStartTime = errors.New("Error peer state invalid startTime")
)
View Source 
var (
	ErrInvalidProposalSignature = errors.New("Error invalid proposal signature")
	ErrInvalidProposalPOLRound  = errors.New("Error invalid proposal POL round")
	ErrAddingVote               = errors.New("Error adding vote")
	ErrVoteHeightMismatch       = errors.New("Error vote height mismatch")
)
View Source 
var Major = "0" //
View Source 
var Minor = "2" // replay refactor
View Source 
var Revision = "2" // validation -> commit
View Source 
var Spec = "1" // async

kind of arbitrary

View Source 
var Version = fmt.Sprintf("v%s/%s.%s.%s", Spec, Major, Minor, Revision)

Functions

func CompareHRS 

func CompareHRS(h1 int64, r1 int, s1 cstypes.RoundStepType, h2 int64, r2 int, s2 cstypes.RoundStepType) int

func IsDataCorruptionError added in v0.15.0 

func IsDataCorruptionError(err error) bool

IsDataCorruptionError returns true if data has been corrupted inside WAL.

func NewWAL 

func NewWAL(walFile string) (*baseWAL, error)

func RegisterConsensusMessages added in v0.19.0 

func RegisterConsensusMessages(cdc *amino.Codec)

func RegisterWALMessages added in v0.19.0 

func RegisterWALMessages(cdc *amino.Codec)

func RunReplayFile added in v0.9.0 

func RunReplayFile(config cfg.BaseConfig, csConfig *cfg.ConsensusConfig, console bool)

replay the wal file

func WALWithNBlocks added in v0.14.0 

func WALWithNBlocks(numBlocks int) (data []byte, err error)

WALWithNBlocks generates a consensus WAL. It does this by spining up a stripped down version of node (proxy app, event bus, consensus state) with a persistent kvstore application and special consensus wal instance (byteBufferWAL) and waits until numBlocks are created. Then it returns a WAL content. If the node fails to produce given numBlocks, it returns an error.

Types

type BlockPartMessage 

type BlockPartMessage struct {
	Height int64
	Round  int
	Part   *types.Part
}

BlockPartMessage is sent when gossipping a piece of the proposed block.

func (*BlockPartMessage) String 

func (m *BlockPartMessage) String() string

String returns a string representation.

type CSOption added in v0.22.0 

type CSOption func(*ConsensusState)

CSOption sets an optional parameter on the ConsensusState.

func WithMetrics added in v0.22.0 

func WithMetrics(metrics *Metrics) CSOption

WithMetrics sets the metrics.

type CommitStepMessage 

type CommitStepMessage struct {
	Height           int64
	BlockPartsHeader types.PartSetHeader
	BlockParts       *cmn.BitArray
}

CommitStepMessage is sent when a block is committed.

func (*CommitStepMessage) String 

func (m *CommitStepMessage) String() string

String returns a string representation.

type ConsensusMessage 

type ConsensusMessage interface{}

ConsensusMessage is a message that can be sent and received on the ConsensusReactor

type ConsensusReactor 

type ConsensusReactor struct {
	p2p.BaseReactor // BaseService + p2p.Switch
	// contains filtered or unexported fields
}

ConsensusReactor defines a reactor for the consensus service.

func NewConsensusReactor 

func NewConsensusReactor(consensusState *ConsensusState, fastSync bool) *ConsensusReactor

NewConsensusReactor returns a new ConsensusReactor with the given consensusState.

func (*ConsensusReactor) AddPeer 

func (conR *ConsensusReactor) AddPeer(peer p2p.Peer)

AddPeer implements Reactor

func (*ConsensusReactor) FastSync added in v0.10.3 

func (conR *ConsensusReactor) FastSync() bool

FastSync returns whether the consensus reactor is in fast-sync mode.

func (*ConsensusReactor) GetChannels 

func (conR *ConsensusReactor) GetChannels() []*p2p.ChannelDescriptor

GetChannels implements Reactor

func (*ConsensusReactor) OnStart 

func (conR *ConsensusReactor) OnStart() error

OnStart implements BaseService by subscribing to events, which later will be broadcasted to other peers and starting state if we're not in fast sync.

func (*ConsensusReactor) OnStop 

func (conR *ConsensusReactor) OnStop()

OnStop implements BaseService by unsubscribing from events and stopping state.

func (*ConsensusReactor) Receive 

func (conR *ConsensusReactor) Receive(chID byte, src p2p.Peer, msgBytes []byte)

Receive implements Reactor NOTE: We process these messages even when we're fast_syncing. Messages affect either a peer state or the consensus state. Peer state updates can happen in parallel, but processing of proposals, block parts, and votes are ordered by the receiveRoutine NOTE: blocks on consensus state for proposals, block parts, and votes

func (*ConsensusReactor) RemovePeer 

func (conR *ConsensusReactor) RemovePeer(peer p2p.Peer, reason interface{})

RemovePeer implements Reactor

func (*ConsensusReactor) SetEventBus added in v0.13.0 

func (conR *ConsensusReactor) SetEventBus(b *types.EventBus)

SetEventBus sets event bus.

func (*ConsensusReactor) String added in v0.8.0 

func (conR *ConsensusReactor) String() string

String returns a string representation of the ConsensusReactor. NOTE: For now, it is just a hard-coded string to avoid accessing unprotected shared variables. TODO: improve!

func (*ConsensusReactor) StringIndented added in v0.8.0 

func (conR *ConsensusReactor) StringIndented(indent string) string

StringIndented returns an indented string representation of the ConsensusReactor

func (*ConsensusReactor) SwitchToConsensus 

func (conR *ConsensusReactor) SwitchToConsensus(state sm.State, blocksSynced int)

SwitchToConsensus switches from fast_sync mode to consensus mode. It resets the state, turns off fast_sync, and starts the consensus state-machine

type ConsensusState 

type ConsensusState struct {
	cmn.BaseService

	cstypes.RoundState
	// contains filtered or unexported fields
}

ConsensusState handles execution of the consensus algorithm. It processes votes and proposals, and upon reaching agreement, commits blocks to the chain and executes them against the application. The internal state machine receives input from peers, the internal validator, and from a timer.

func NewConsensusState 

func NewConsensusState(
	config *cfg.ConsensusConfig,
	state sm.State,
	blockExec *sm.BlockExecutor,
	blockStore sm.BlockStore,
	mempool sm.Mempool,
	evpool sm.EvidencePool,
	options ...CSOption,
) *ConsensusState

NewConsensusState returns a new ConsensusState.

func (*ConsensusState) AddProposalBlockPart 

func (cs *ConsensusState) AddProposalBlockPart(height int64, round int, part *types.Part, peerID p2p.ID) error

AddProposalBlockPart inputs a part of the proposal block.

func (*ConsensusState) AddVote 

func (cs *ConsensusState) AddVote(vote *types.Vote, peerID p2p.ID) (added bool, err error)

AddVote inputs a vote.

func (*ConsensusState) GetLastHeight added in v0.24.0 

func (cs *ConsensusState) GetLastHeight() int64

GetLastHeight returns the last height committed. If there were no blocks, returns 0.

func (*ConsensusState) GetRoundState 

func (cs *ConsensusState) GetRoundState() *cstypes.RoundState

GetRoundState returns a shallow copy of the internal consensus state.

func (*ConsensusState) GetRoundStateJSON added in v0.19.0 

func (cs *ConsensusState) GetRoundStateJSON() ([]byte, error)

GetRoundStateJSON returns a json of RoundState, marshalled using go-amino.

func (*ConsensusState) GetRoundStateSimpleJSON added in v0.19.3 

func (cs *ConsensusState) GetRoundStateSimpleJSON() ([]byte, error)

GetRoundStateSimpleJSON returns a json of RoundStateSimple, marshalled using go-amino.

func (*ConsensusState) GetState 

func (cs *ConsensusState) GetState() sm.State

GetState returns a copy of the chain state.

func (*ConsensusState) GetValidators added in v0.7.3 

func (cs *ConsensusState) GetValidators() (int64, []*types.Validator)

GetValidators returns a copy of the current validators.

func (*ConsensusState) LoadCommit added in v0.8.0 

func (cs *ConsensusState) LoadCommit(height int64) *types.Commit

LoadCommit loads the commit for a given height.

func (*ConsensusState) OnStart 

func (cs *ConsensusState) OnStart() error

OnStart implements cmn.Service. It loads the latest state via the WAL, and starts the timeout and receive routines.

func (*ConsensusState) OnStop 

func (cs *ConsensusState) OnStop()

OnStop implements cmn.Service. It stops all routines and waits for the WAL to finish.

func (*ConsensusState) OpenWAL 

func (cs *ConsensusState) OpenWAL(walFile string) (WAL, error)

OpenWAL opens a file to log all consensus messages and timeouts for deterministic accountability

func (*ConsensusState) ReplayFile added in v0.9.0 

func (cs *ConsensusState) ReplayFile(file string, console bool) error

Replay msgs in file or start the console

func (*ConsensusState) SetEventBus added in v0.13.0 

func (cs *ConsensusState) SetEventBus(b *types.EventBus)

SetEventBus sets event bus.

func (*ConsensusState) SetLogger added in v0.10.0 

func (cs *ConsensusState) SetLogger(l log.Logger)

SetLogger implements Service.

func (*ConsensusState) SetPrivValidator 

func (cs *ConsensusState) SetPrivValidator(priv types.PrivValidator)

SetPrivValidator sets the private validator account for signing votes.

func (*ConsensusState) SetProposal 

func (cs *ConsensusState) SetProposal(proposal *types.Proposal, peerID p2p.ID) error

SetProposal inputs a proposal.

func (*ConsensusState) SetProposalAndBlock 

func (cs *ConsensusState) SetProposalAndBlock(proposal *types.Proposal, block *types.Block, parts *types.PartSet, peerID p2p.ID) error

SetProposalAndBlock inputs the proposal and all block parts.

func (*ConsensusState) SetTimeoutTicker added in v0.8.0 

func (cs *ConsensusState) SetTimeoutTicker(timeoutTicker TimeoutTicker)

SetTimeoutTicker sets the local timer. It may be useful to overwrite for testing.

func (*ConsensusState) String 

func (cs *ConsensusState) String() string

String returns a string.

func (*ConsensusState) Wait added in v0.8.0 

func (cs *ConsensusState) Wait()

Wait waits for the the main routine to return. NOTE: be sure to Stop() the event switch and drain any event channels or this may deadlock

type DataCorruptionError added in v0.15.0 

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

DataCorruptionError is an error that occures if data on disk was corrupted.

func (DataCorruptionError) Cause added in v0.15.0 

func (e DataCorruptionError) Cause() error

func (DataCorruptionError) Error added in v0.15.0 

func (e DataCorruptionError) Error() string

type EndHeightMessage added in v0.12.0 

type EndHeightMessage struct {
	Height int64 `json:"height"`
}

EndHeightMessage marks the end of the given height inside WAL. @internal used by scripts/wal2json util.

type Handshaker added in v0.9.0 

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

func NewHandshaker added in v0.9.0 

func NewHandshaker(stateDB dbm.DB, state sm.State,
	store sm.BlockStore, genDoc *types.GenesisDoc) *Handshaker

func (*Handshaker) Handshake added in v0.9.0 

func (h *Handshaker) Handshake(proxyApp proxy.AppConns) error

TODO: retry the handshake/replay if it fails ?

func (*Handshaker) NBlocks added in v0.9.0 

func (h *Handshaker) NBlocks() int

func (*Handshaker) ReplayBlocks added in v0.9.0 

func (h *Handshaker) ReplayBlocks(state sm.State, appHash []byte, appBlockHeight int64, proxyApp proxy.AppConns) ([]byte, error)

Replay all blocks since appBlockHeight and ensure the result matches the current state. Returns the final AppHash or an error.

func (*Handshaker) SetLogger added in v0.10.0 

func (h *Handshaker) SetLogger(l log.Logger)

type HasVoteMessage 

type HasVoteMessage struct {
	Height int64
	Round  int
	Type   byte
	Index  int
}

HasVoteMessage is sent to indicate that a particular vote has been received.

func (*HasVoteMessage) String 

func (m *HasVoteMessage) String() string

String returns a string representation.

type Metrics added in v0.22.0 

type Metrics struct {
	// Height of the chain.
	Height metrics.Gauge

	// Number of rounds.
	Rounds metrics.Gauge

	// Number of validators.
	Validators metrics.Gauge
	// Total power of all validators.
	ValidatorsPower metrics.Gauge
	// Number of validators who did not sign.
	MissingValidators metrics.Gauge
	// Total power of the missing validators.
	MissingValidatorsPower metrics.Gauge
	// Number of validators who tried to double sign.
	ByzantineValidators metrics.Gauge
	// Total power of the byzantine validators.
	ByzantineValidatorsPower metrics.Gauge

	// Time between this and the last block.
	BlockIntervalSeconds metrics.Histogram

	// Number of transactions.
	NumTxs metrics.Gauge
	// Size of the block.
	BlockSizeBytes metrics.Gauge
	// Total number of transactions.
	TotalTxs metrics.Gauge
}

Metrics contains metrics exposed by this package.

func NopMetrics added in v0.22.0 

func NopMetrics() *Metrics

NopMetrics returns no-op Metrics.

func PrometheusMetrics added in v0.22.0 

func PrometheusMetrics() *Metrics

PrometheusMetrics returns Metrics build using Prometheus client library.

type NewRoundStepMessage 

type NewRoundStepMessage struct {
	Height                int64
	Round                 int
	Step                  cstypes.RoundStepType
	SecondsSinceStartTime int
	LastCommitRound       int
}

NewRoundStepMessage is sent for every step taken in the ConsensusState. For every height/round/step transition

func (*NewRoundStepMessage) String 

func (m *NewRoundStepMessage) String() string

String returns a string representation.

type PeerState 

type PeerState struct {
	PRS   cstypes.PeerRoundState `json:"round_state"` // Exposed.
	Stats *peerStateStats        `json:"stats"`       // Exposed.
	// contains filtered or unexported fields
}

PeerState contains the known state of a peer, including its connection and threadsafe access to its PeerRoundState. NOTE: THIS GETS DUMPED WITH rpc/core/consensus.go. Be mindful of what you Expose.

func NewPeerState 

func NewPeerState(peer p2p.Peer) *PeerState

NewPeerState returns a new PeerState for the given Peer

func (*PeerState) ApplyCommitStepMessage 

func (ps *PeerState) ApplyCommitStepMessage(msg *CommitStepMessage)

ApplyCommitStepMessage updates the peer state for the new commit.

func (*PeerState) ApplyHasVoteMessage 

func (ps *PeerState) ApplyHasVoteMessage(msg *HasVoteMessage)

ApplyHasVoteMessage updates the peer state for the new vote.

func (*PeerState) ApplyNewRoundStepMessage 

func (ps *PeerState) ApplyNewRoundStepMessage(msg *NewRoundStepMessage)

ApplyNewRoundStepMessage updates the peer state for the new round.

func (*PeerState) ApplyProposalPOLMessage 

func (ps *PeerState) ApplyProposalPOLMessage(msg *ProposalPOLMessage)

ApplyProposalPOLMessage updates the peer state for the new proposal POL.

func (*PeerState) ApplyVoteSetBitsMessage added in v0.8.0 

func (ps *PeerState) ApplyVoteSetBitsMessage(msg *VoteSetBitsMessage, ourVotes *cmn.BitArray)

ApplyVoteSetBitsMessage updates the peer state for the bit-array of votes it claims to have for the corresponding BlockID. `ourVotes` is a BitArray of votes we have for msg.BlockID NOTE: if ourVotes is nil (e.g. msg.Height < rs.Height), we conservatively overwrite ps's votes w/ msg.Votes.

func (*PeerState) BlockPartsSent added in v0.17.0 

func (ps *PeerState) BlockPartsSent() int

BlockPartsSent returns the number of blocks for which peer has been sending us block parts.

func (*PeerState) EnsureVoteBitArrays 

func (ps *PeerState) EnsureVoteBitArrays(height int64, numValidators int)

EnsureVoteBitArrays ensures the bit-arrays have been allocated for tracking what votes this peer has received. NOTE: It's important to make sure that numValidators actually matches what the node sees as the number of validators for height.

func (*PeerState) GetHeight 

func (ps *PeerState) GetHeight() int64

GetHeight returns an atomic snapshot of the PeerRoundState's height used by the mempool to ensure peers are caught up before broadcasting new txs

func (*PeerState) GetRoundState 

func (ps *PeerState) GetRoundState() *cstypes.PeerRoundState

GetRoundState returns an shallow copy of the PeerRoundState. There's no point in mutating it since it won't change PeerState.

func (*PeerState) InitProposalBlockParts added in v0.13.0 

func (ps *PeerState) InitProposalBlockParts(partsHeader types.PartSetHeader)

InitProposalBlockParts initializes the peer's proposal block parts header and bit array.

func (*PeerState) PickSendVote 

func (ps *PeerState) PickSendVote(votes types.VoteSetReader) bool

PickSendVote picks a vote and sends it to the peer. Returns true if vote was sent.

func (*PeerState) PickVoteToSend 

func (ps *PeerState) PickVoteToSend(votes types.VoteSetReader) (vote *types.Vote, ok bool)

PickVoteToSend picks a vote to send to the peer. Returns true if a vote was picked. NOTE: `votes` must be the correct Size() for the Height().

func (*PeerState) RecordBlockPart added in v0.17.0 

func (ps *PeerState) RecordBlockPart(bp *BlockPartMessage) int

RecordBlockPart updates internal statistics for this peer by recording the block part. It returns the total number of block parts (1 per block). This essentially means the number of blocks for which peer has been sending us block parts.

func (*PeerState) RecordVote added in v0.17.0 

func (ps *PeerState) RecordVote(vote *types.Vote) int

RecordVote updates internal statistics for this peer by recording the vote. It returns the total number of votes (1 per block). This essentially means the number of blocks for which peer has been sending us votes.

func (*PeerState) SetHasProposal 

func (ps *PeerState) SetHasProposal(proposal *types.Proposal)

SetHasProposal sets the given proposal as known for the peer.

func (*PeerState) SetHasProposalBlockPart 

func (ps *PeerState) SetHasProposalBlockPart(height int64, round int, index int)

SetHasProposalBlockPart sets the given block part index as known for the peer.

func (*PeerState) SetHasVote 

func (ps *PeerState) SetHasVote(vote *types.Vote)

SetHasVote sets the given vote as known by the peer

func (*PeerState) SetLogger added in v0.11.0 

func (ps *PeerState) SetLogger(logger log.Logger) *PeerState

SetLogger allows to set a logger on the peer state. Returns the peer state itself.

func (*PeerState) String added in v0.8.0 

func (ps *PeerState) String() string

String returns a string representation of the PeerState

func (*PeerState) StringIndented added in v0.8.0 

func (ps *PeerState) StringIndented(indent string) string

StringIndented returns a string representation of the PeerState

func (*PeerState) ToJSON added in v0.19.3 

func (ps *PeerState) ToJSON() ([]byte, error)

ToJSON returns a json of PeerState, marshalled using go-amino.

func (*PeerState) VotesSent added in v0.17.0 

func (ps *PeerState) VotesSent() int

VotesSent returns the number of blocks for which peer has been sending us votes.

type ProposalHeartbeatMessage added in v0.10.3 

type ProposalHeartbeatMessage struct {
	Heartbeat *types.Heartbeat
}

ProposalHeartbeatMessage is sent to signal that a node is alive and waiting for transactions for a proposal.

func (*ProposalHeartbeatMessage) String added in v0.10.3 

func (m *ProposalHeartbeatMessage) String() string

String returns a string representation.

type ProposalMessage 

type ProposalMessage struct {
	Proposal *types.Proposal
}

ProposalMessage is sent when a new block is proposed.

func (*ProposalMessage) String 

func (m *ProposalMessage) String() string

String returns a string representation.

type ProposalPOLMessage 

type ProposalPOLMessage struct {
	Height           int64
	ProposalPOLRound int
	ProposalPOL      *cmn.BitArray
}

ProposalPOLMessage is sent when a previous proposal is re-proposed.

func (*ProposalPOLMessage) String 

func (m *ProposalPOLMessage) String() string

String returns a string representation.

type TimedWALMessage added in v0.8.0 

type TimedWALMessage struct {
	Time time.Time  `json:"time"` // for debugging purposes
	Msg  WALMessage `json:"msg"`
}

type TimeoutTicker added in v0.8.0 

type TimeoutTicker interface {
	Start() error
	Stop() error
	Chan() <-chan timeoutInfo       // on which to receive a timeout
	ScheduleTimeout(ti timeoutInfo) // reset the timer

	SetLogger(log.Logger)
}

TimeoutTicker is a timer that schedules timeouts conditional on the height/round/step in the timeoutInfo. The timeoutInfo.Duration may be non-positive.

func NewTimeoutTicker added in v0.8.0 

func NewTimeoutTicker() TimeoutTicker

NewTimeoutTicker returns a new TimeoutTicker.

type VoteMessage 

type VoteMessage struct {
	Vote *types.Vote
}

VoteMessage is sent when voting for a proposal (or lack thereof).

func (*VoteMessage) String 

func (m *VoteMessage) String() string

String returns a string representation.

type VoteSetBitsMessage added in v0.8.0 

type VoteSetBitsMessage struct {
	Height  int64
	Round   int
	Type    byte
	BlockID types.BlockID
	Votes   *cmn.BitArray
}

VoteSetBitsMessage is sent to communicate the bit-array of votes seen for the BlockID.

func (*VoteSetBitsMessage) String added in v0.8.0 

func (m *VoteSetBitsMessage) String() string

String returns a string representation.

type VoteSetMaj23Message added in v0.8.0 

type VoteSetMaj23Message struct {
	Height  int64
	Round   int
	Type    byte
	BlockID types.BlockID
}

VoteSetMaj23Message is sent to indicate that a given BlockID has seen +2/3 votes.

func (*VoteSetMaj23Message) String added in v0.8.0 

func (m *VoteSetMaj23Message) String() string

String returns a string representation.

type WAL 

type WAL interface {
	Write(WALMessage)
	WriteSync(WALMessage)
	Group() *auto.Group
	SearchForEndHeight(height int64, options *WALSearchOptions) (gr *auto.GroupReader, found bool, err error)

	Start() error
	Stop() error
	Wait()
}

WAL is an interface for any write-ahead logger.

type WALDecoder added in v0.12.0 

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

A WALDecoder reads and decodes custom-encoded WAL messages from an input stream. See WALEncoder for the format used.

It will also compare the checksums and make sure data size is equal to the length from the header. If that is not the case, error will be returned.

func NewWALDecoder added in v0.12.0 

func NewWALDecoder(rd io.Reader) *WALDecoder

NewWALDecoder returns a new decoder that reads from rd.

func (*WALDecoder) Decode added in v0.12.0 

func (dec *WALDecoder) Decode() (*TimedWALMessage, error)

Decode reads the next custom-encoded value from its reader and returns it.

type WALEncoder added in v0.12.0 

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

A WALEncoder writes custom-encoded WAL messages to an output stream.

Format: 4 bytes CRC sum + 4 bytes length + arbitrary-length value (go-amino encoded)

func NewWALEncoder added in v0.12.0 

func NewWALEncoder(wr io.Writer) *WALEncoder

NewWALEncoder returns a new encoder that writes to wr.

func (*WALEncoder) Encode added in v0.12.0 

func (enc *WALEncoder) Encode(v *TimedWALMessage) error

Encode writes the custom encoding of v to the stream.

type WALMessage added in v0.8.0 

type WALMessage interface{}

type WALSearchOptions added in v0.15.0 

type WALSearchOptions struct {
	// IgnoreDataCorruptionErrors set to true will result in skipping data corruption errors.
	IgnoreDataCorruptionErrors bool
}

WALSearchOptions are optional arguments to SearchForEndHeight.

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