Add txselector base

txselector/txselector.go

@@ -0,0 +1,142 @@
+package txselector
+
+import (
+	"sort"
+
+	"github.com/hermeznetwork/hermez-node/tx-selector/common"
+	"github.com/hermeznetwork/hermez-node/tx-selector/mock"
+)
+
+// txs implements the interface Sort for an array of Tx
+type txs []common.Tx
+
+func (t txs) Len() int {
+	return len(t)
+}
+func (t txs) Swap(i, j int) {
+	t[i], t[j] = t[j], t[i]
+}
+func (t txs) Less(i, j int) bool {
+	return t[i].UserFeeAbsolute > t[j].UserFeeAbsolute
+}
+
+type TxSelector struct {
+	// NMax is the maximum L1-user-tx for a batch
+	NMax uint64
+	// MMax is the maximum L1-operator-tx for a batch
+	MMax uint64
+	// PMax is the maximum L2-tx for a batch
+	PMax uint64
+	// DB is a pointer to the database interface
+	DB *mock.MockDB
+}
+
+func NewTxSelector(db *mock.MockDB, nMax, mMax, pMax uint64) *TxSelector {
+	return &TxSelector{
+		NMax: nMax,
+		MMax: mMax,
+		PMax: pMax,
+		DB:   db,
+	}
+}
+
+func (txsel *TxSelector) updateLocalAccountDB(batchId uint64) error {
+	// if batchID > max(localAccountDB.BatchID) + 1
+	//     make a checkpoint of AccountDB at BatchID to a localAccountDB
+	// use localAccountDB[inputBatchID-1]
+
+	return nil
+}
+
+func (txsel *TxSelector) GetL2TxSelection(batchID uint64) ([]common.Tx, error) {
+	err := txsel.updateLocalAccountDB(batchID)
+	if err != nil {
+		return nil, err
+	}
+
+	// get pending l2-tx from tx-pool
+	txsRaw := txsel.DB.GetTxs(batchID)
+
+	// discard the txs that don't have an Account in the AccountDB
+	var validTxs txs
+	for _, tx := range txsRaw {
+		accountID := getAccountID(tx.ToEthAddr, tx.TokenID)
+		if _, ok := txsel.DB.AccountDB[accountID]; ok {
+			validTxs = append(validTxs, tx)
+		}
+	}
+
+	// get most profitable L2-tx (len<NMax)
+	txs := txsel.getL2Profitable(validTxs)
+
+	// apply L2-tx to local AccountDB, make checkpoint tagged with BatchID
+	//     update balances
+	//     update nonces
+
+	// return selected txs
+	return txs, nil
+}
+
+func (txsel *TxSelector) GetL1L2TxSelection(batchID uint64, l1txs []common.Tx) ([]common.Tx, []common.Tx, []common.Tx, error) {
+	err := txsel.updateLocalAccountDB(batchID)
+	if err != nil {
+		return nil, nil, nil, err
+	}
+
+	// apply l1-user-tx to localAccountDB
+	//     create new leaves
+	//     update balances
+	//     update nonces
+
+	// get pending l2-tx from tx-pool
+	txsRaw := txsel.DB.GetTxs(batchID)
+
+	// discard the txs that don't have an Account in the AccountDB
+	// neither appear in the PendingRegistersDB
+	var validTxs txs
+	for _, tx := range txsRaw {
+		accountID := getAccountID(tx.ToEthAddr, tx.TokenID)
+		exist := txsel.checkIfAccountExist(accountID)
+		if exist {
+			validTxs = append(validTxs, tx)
+		}
+	}
+
+	// get most profitable L2-tx (len<NMax)
+	l2txs := txsel.getL2Profitable(validTxs)
+
+	// prepare (from the selected l2txs) pending to register from the PendingRegistersDB
+	var pendingRegisters []common.Account
+	for _, tx := range l2txs {
+		accountID := getAccountID(tx.ToEthAddr, tx.TokenID)
+		if toRegister, ok := txsel.DB.PendingRegistersDB[accountID]; ok {
+			pendingRegisters = append(pendingRegisters, toRegister)
+		}
+	}
+
+	// create L1-operator-tx for each L2-tx selected in which the recipient does not have account
+	l1OperatorTxs := txsel.createL1OperatorTxForL2Tx(pendingRegisters) // only with the L2-tx selected ones
+
+	return l1txs, l2txs, l1OperatorTxs, nil
+}
+
+func (txsel *TxSelector) checkIfAccountExist(accountID [36]byte) bool {
+	// check if account exist in AccountDB
+	if _, ok := txsel.DB.AccountDB[accountID]; ok {
+		return true
+	}
+	// check if account is pending to register
+	if _, ok := txsel.DB.PendingRegistersDB[accountID]; ok {
+		return true
+	}
+	return false
+}
+
+func (txsel *TxSelector) getL2Profitable(txs txs) txs {
+	sort.Sort(txs)
+	return txs[:txsel.PMax]
+}
+func (txsel *TxSelector) createL1OperatorTxForL2Tx(accounts []common.Account) txs {
+	//
+	return txs{}
+}