package mempool import ( "fmt" abci "github.com/tendermint/tendermint/abci/types" "github.com/tendermint/tendermint/types" ) // Mempool defines the mempool interface. // // Updates to the mempool need to be synchronized with committing a block so // apps can reset their transient state on Commit. type Mempool interface { // CheckTx executes a new transaction against the application to determine // its validity and whether it should be added to the mempool. CheckTx(tx types.Tx, callback func(*abci.Response)) error // CheckTxWithInfo performs the same operation as CheckTx, but with extra // meta data about the tx. // Currently this metadata is the peer who sent it, used to prevent the tx // from being gossiped back to them. CheckTxWithInfo(tx types.Tx, callback func(*abci.Response), txInfo TxInfo) error // ReapMaxBytesMaxGas reaps transactions from the mempool up to maxBytes // bytes total with the condition that the total gasWanted must be less than // maxGas. // If both maxes are negative, there is no cap on the size of all returned // transactions (~ all available transactions). ReapMaxBytesMaxGas(maxBytes, maxGas int64) types.Txs // ReapMaxTxs reaps up to max transactions from the mempool. // If max is negative, there is no cap on the size of all returned // transactions (~ all available transactions). ReapMaxTxs(max int) types.Txs // Lock locks the mempool. The consensus must be able to hold lock to safely update. Lock() // Unlock unlocks the mempool. Unlock() // Update informs the mempool that the given txs were committed and can be discarded. // NOTE: this should be called *after* block is committed by consensus. // NOTE: unsafe; Lock/Unlock must be managed by caller Update(blockHeight int64, blockTxs types.Txs, newPreFn PreCheckFunc, newPostFn PostCheckFunc) error // FlushAppConn flushes the mempool connection to ensure async reqResCb calls are // done. E.g. from CheckTx. FlushAppConn() error // Flush removes all transactions from the mempool and cache Flush() // TxsAvailable returns a channel which fires once for every height, // and only when transactions are available in the mempool. // NOTE: the returned channel may be nil if EnableTxsAvailable was not called. TxsAvailable() <-chan struct{} // EnableTxsAvailable initializes the TxsAvailable channel, ensuring it will // trigger once every height when transactions are available. EnableTxsAvailable() // Size returns the number of transactions in the mempool. Size() int // TxsBytes returns the total size of all txs in the mempool. TxsBytes() int64 // InitWAL creates a directory for the WAL file and opens a file itself. InitWAL() // CloseWAL closes and discards the underlying WAL file. // Any further writes will not be relayed to disk. CloseWAL() } //-------------------------------------------------------------------------------- // PreCheckFunc is an optional filter executed before CheckTx and rejects // transaction if false is returned. An example would be to ensure that a // transaction doesn't exceeded the block size. type PreCheckFunc func(types.Tx) error // PostCheckFunc is an optional filter executed after CheckTx and rejects // transaction if false is returned. An example would be to ensure a // transaction doesn't require more gas than available for the block. type PostCheckFunc func(types.Tx, *abci.ResponseCheckTx) error // TxInfo are parameters that get passed when attempting to add a tx to the // mempool. type TxInfo struct { // We don't use p2p.ID here because it's too big. The gain is to store max 2 // bytes with each tx to identify the sender rather than 20 bytes. SenderID uint16 } //-------------------------------------------------------------------------------- // PreCheckAminoMaxBytes checks that the size of the transaction plus the amino // overhead is smaller or equal to the expected maxBytes. func PreCheckAminoMaxBytes(maxBytes int64) PreCheckFunc { return func(tx types.Tx) error { // We have to account for the amino overhead in the tx size as well // NOTE: fieldNum = 1 as types.Block.Data contains Txs []Tx as first field. // If this field order ever changes this needs to updated here accordingly. // NOTE: if some []Tx are encoded without a parenting struct, the // fieldNum is also equal to 1. aminoOverhead := types.ComputeAminoOverhead(tx, 1) txSize := int64(len(tx)) + aminoOverhead if txSize > maxBytes { return fmt.Errorf("Tx size (including amino overhead) is too big: %d, max: %d", txSize, maxBytes) } return nil } } // PostCheckMaxGas checks that the wanted gas is smaller or equal to the passed // maxGas. Returns nil if maxGas is -1. func PostCheckMaxGas(maxGas int64) PostCheckFunc { return func(tx types.Tx, res *abci.ResponseCheckTx) error { if maxGas == -1 { return nil } if res.GasWanted < 0 { return fmt.Errorf("gas wanted %d is negative", res.GasWanted) } if res.GasWanted > maxGas { return fmt.Errorf("gas wanted %d is greater than max gas %d", res.GasWanted, maxGas) } return nil } }