blockbook/bchain/mempool.go

74 lines
1.9 KiB
Go

package bchain
import (
"encoding/hex"
"sync"
"github.com/golang/glog"
)
// Mempool is mempool handle.
type Mempool struct {
chain *BitcoinRPC
mux sync.Mutex
scriptToTx map[string][]string
txToScript map[string][]string
}
// NewMempool creates new mempool handler.
func NewMempool(chain *BitcoinRPC) *Mempool {
return &Mempool{chain: chain}
}
// GetTransactions returns slice of mempool transactions for given output script.
func (m *Mempool) GetTransactions(outputScript []byte) ([]string, error) {
m.mux.Lock()
defer m.mux.Unlock()
scriptHex := hex.EncodeToString(outputScript)
return m.scriptToTx[scriptHex], nil
}
func (m *Mempool) updateMaps(newScriptToTx map[string][]string, newTxToScript map[string][]string) {
m.mux.Lock()
defer m.mux.Unlock()
m.scriptToTx = newScriptToTx
m.txToScript = newTxToScript
}
// Resync gets mempool transactions and maps output scripts to transactions.
// Resync is not reentrant, it should be called from a single thread.
// Read operations (GetTransactions) are safe.
func (m *Mempool) Resync() error {
glog.Info("Mempool: resync")
txs, err := m.chain.GetMempool()
if err != nil {
return err
}
newScriptToTx := make(map[string][]string)
newTxToScript := make(map[string][]string)
for _, txid := range txs {
scripts := m.txToScript[txid]
if scripts == nil {
tx, err := m.chain.GetTransaction(txid)
if err != nil {
glog.Error("cannot get transaction ", txid, ": ", err)
continue
}
scripts = make([]string, 0, len(tx.Vout))
for _, output := range tx.Vout {
outputScript := output.ScriptPubKey.Hex
if outputScript != "" {
scripts = append(scripts, outputScript)
}
}
}
newTxToScript[txid] = scripts
for _, script := range scripts {
newScriptToTx[script] = append(newScriptToTx[script], txid)
}
}
m.updateMaps(newScriptToTx, newTxToScript)
glog.Info("Mempool: resync finished, ", len(m.txToScript), " transactions in mempool")
return nil
}