package mempool import ( "bytes" "fmt" "reflect" "time" abci "github.com/tendermint/abci/types" wire "github.com/tendermint/go-wire" "github.com/tendermint/tmlibs/clist" "github.com/tendermint/tmlibs/log" cfg "github.com/tendermint/tendermint/config" "github.com/tendermint/tendermint/p2p" "github.com/tendermint/tendermint/types" ) const ( MempoolChannel = byte(0x30) maxMempoolMessageSize = 1048576 // 1MB TODO make it configurable peerCatchupSleepIntervalMS = 100 // If peer is behind, sleep this amount ) // MempoolReactor handles mempool tx broadcasting amongst peers. type MempoolReactor struct { p2p.BaseReactor config *cfg.MempoolConfig Mempool *Mempool } // NewMempoolReactor returns a new MempoolReactor with the given config and mempool. func NewMempoolReactor(config *cfg.MempoolConfig, mempool *Mempool) *MempoolReactor { memR := &MempoolReactor{ config: config, Mempool: mempool, } memR.BaseReactor = *p2p.NewBaseReactor("MempoolReactor", memR) return memR } // SetLogger sets the Logger on the reactor and the underlying Mempool. func (memR *MempoolReactor) SetLogger(l log.Logger) { memR.Logger = l memR.Mempool.SetLogger(l) } // GetChannels implements Reactor. // It returns the list of channels for this reactor. func (memR *MempoolReactor) GetChannels() []*p2p.ChannelDescriptor { return []*p2p.ChannelDescriptor{ { ID: MempoolChannel, Priority: 5, }, } } // AddPeer implements Reactor. // It starts a broadcast routine ensuring all txs are forwarded to the given peer. func (memR *MempoolReactor) AddPeer(peer p2p.Peer) { go memR.broadcastTxRoutine(peer) } // RemovePeer implements Reactor. func (memR *MempoolReactor) RemovePeer(peer p2p.Peer, reason interface{}) { // broadcast routine checks if peer is gone and returns } // Receive implements Reactor. // It adds any received transactions to the mempool. func (memR *MempoolReactor) Receive(chID byte, src p2p.Peer, msgBytes []byte) { _, msg, err := DecodeMessage(msgBytes) if err != nil { memR.Logger.Error("Error decoding message", "err", err) return } memR.Logger.Debug("Receive", "src", src, "chId", chID, "msg", msg) switch msg := msg.(type) { case *TxMessage: err := memR.Mempool.CheckTx(msg.Tx, nil) if err != nil { memR.Logger.Info("Could not check tx", "tx", msg.Tx, "err", err) } // broadcasting happens from go routines per peer default: memR.Logger.Error(fmt.Sprintf("Unknown message type %v", reflect.TypeOf(msg))) } } // BroadcastTx is an alias for Mempool.CheckTx. Broadcasting itself happens in peer routines. func (memR *MempoolReactor) BroadcastTx(tx types.Tx, cb func(*abci.Response)) error { return memR.Mempool.CheckTx(tx, cb) } // PeerState describes the state of a peer. type PeerState interface { GetHeight() int64 } // Send new mempool txs to peer. // TODO: Handle mempool or reactor shutdown? // As is this routine may block forever if no new txs come in. func (memR *MempoolReactor) broadcastTxRoutine(peer p2p.Peer) { if !memR.config.Broadcast { return } var next *clist.CElement for { if !memR.IsRunning() || !peer.IsRunning() { return // Quit! } if next == nil { // This happens because the CElement we were looking at got // garbage collected (removed). That is, .NextWait() returned nil. // Go ahead and start from the beginning. next = memR.Mempool.TxsFrontWait() // Wait until a tx is available } memTx := next.Value.(*mempoolTx) // make sure the peer is up to date height := memTx.Height() if peerState_i := peer.Get(types.PeerStateKey); peerState_i != nil { peerState := peerState_i.(PeerState) if peerState.GetHeight() < height-1 { // Allow for a lag of 1 block time.Sleep(peerCatchupSleepIntervalMS * time.Millisecond) continue } } // send memTx msg := &TxMessage{Tx: memTx.tx} success := peer.Send(MempoolChannel, struct{ MempoolMessage }{msg}) if !success { time.Sleep(peerCatchupSleepIntervalMS * time.Millisecond) continue } next = next.NextWait() continue } } //----------------------------------------------------------------------------- // Messages const ( msgTypeTx = byte(0x01) ) // MempoolMessage is a message sent or received by the MempoolReactor. type MempoolMessage interface{} var _ = wire.RegisterInterface( struct{ MempoolMessage }{}, wire.ConcreteType{&TxMessage{}, msgTypeTx}, ) // DecodeMessage decodes a byte-array into a MempoolMessage. func DecodeMessage(bz []byte) (msgType byte, msg MempoolMessage, err error) { msgType = bz[0] n := new(int) r := bytes.NewReader(bz) msg = wire.ReadBinary(struct{ MempoolMessage }{}, r, maxMempoolMessageSize, n, &err).(struct{ MempoolMessage }).MempoolMessage return } //------------------------------------- // TxMessage is a MempoolMessage containing a transaction. type TxMessage struct { Tx types.Tx } // String returns a string representation of the TxMessage. func (m *TxMessage) String() string { return fmt.Sprintf("[TxMessage %v]", m.Tx) }