Add estimation logic

Author: zivkovicmilos

internal/common/common.go

@@ -4,21 +4,13 @@ import "github.com/gnolang/gno/tm2/pkg/std"
 
 const Denomination = "ugnot"
 
-// TODO support estimating gas params
-// These are constants for now,
-// but should be fetched as estimations
-// from the Tendermint node once this functionality
-// is available.
-//
-// Each package call / deployment
-// costs a fixed 1 GNOT
-// https://github.com/gnolang/gno/issues/649
 var (
 	DefaultGasFee = std.Coin{
 		Denom:  Denomination,
-		Amount: 1,
+		Amount: 5,
 	}
 
+	// TODO remove
 	InitialTxCost = std.Coin{
 		Denom:  Denomination,
 		Amount: 1000000, // 1 GNOT

internal/distributor/distributor.go

@@ -19,6 +19,7 @@ var errInsufficientFunds = errors.New("insufficient distributor funds")
 type Client interface {
 	GetAccount(address string) (*gnoland.GnoAccount, error)
 	BroadcastTransaction(tx *std.Tx) error
+	EstimateGas(tx *std.Tx) (int64, error)
 }
 
 // Distributor is the process
@@ -66,7 +67,7 @@ func calculateRuntimeCosts(totalTx int64) std.Coin {
 	// NOTE: Since there is no gas estimation support yet, this value
 	// is fixed, but it will change in the future once pricing estimations
 	// are added
-	baseTxCost := common.DefaultGasFee.Add(common.InitialTxCost)
+	baseTxCost := common.DefaultGasFee
 
 	// Each account should have enough funds
 	// to execute the entire run

internal/pipeline.go

@@ -110,6 +110,7 @@ func (p *Pipeline) Execute() error {
 		runAccounts,
 		p.cfg.Transactions,
 		p.cfg.ChainID,
+		p.cli.EstimateGas,
 	)
 	if err != nil {
 		return fmt.Errorf("unable to construct transactions, %w", err)
@@ -205,7 +206,12 @@ func prepareRuntime(
 	}
 
 	// Get the predeploy transactions
-	predeployTxs, err := txRuntime.Initialize(deployer, deployerKey, chainID)
+	predeployTxs, err := txRuntime.Initialize(
+		deployer,
+		deployerKey,
+		chainID,
+		cli.EstimateGas,
+	)
 	if err != nil {
 		return fmt.Errorf("unable to initialize runtime, %w", err)
 	}

internal/runtime/helper.go

@@ -20,6 +20,7 @@ func constructTransactions(
 	transactions uint64,
 	chainID string,
 	getMsg msgFn,
+	estimateFn EstimateGasFn,
 ) ([]*std.Tx, error) {
 	var (
 		txs = make([]*std.Tx, transactions)
@@ -30,6 +31,50 @@ func constructTransactions(
 		nonceMap = make(map[uint64]uint64) // accountNumber -> nonce
 	)
 
+	fmt.Printf("\n🔨 Estimating Gas 🔨\n\n")
+
+	// Estimate the fee for the transaction batch
+	txFee := defaultDeployTxFee
+
+	// Construct the first tx
+	// Generate the transaction
+	var (
+		creator    = accounts[0]
+		creatorKey = keys[0]
+	)
+
+	tx := &std.Tx{
+		Msgs: []std.Msg{getMsg(creator, 0)},
+		Fee:  txFee,
+	}
+
+	// Sign the transaction
+	cfg := signer.SignCfg{
+		ChainID:       chainID,
+		AccountNumber: creator.GetAccountNumber(),
+		Sequence:      creator.GetSequence(),
+	}
+
+	if err := signer.SignTx(tx, creatorKey, cfg); err != nil {
+		return nil, fmt.Errorf("unable to sign transaction, %w", err)
+	}
+
+	gasWanted, err := estimateFn(tx)
+	if err != nil {
+		return nil, fmt.Errorf("unable to estimate gas, %w", err)
+	}
+
+	// Clear the old signatures, because they need
+	// to be regenerated
+	clear(tx.Signatures)
+
+	// Use the estimated gas limit
+	txFee.GasWanted = gasWanted + 10_000 // 10k gas buffer
+
+	if err = signer.SignTx(tx, creatorKey, cfg); err != nil {
+		return nil, fmt.Errorf("unable to sign transaction, %w", err)
+	}
+
 	fmt.Printf("\n🔨 Constructing Transactions 🔨\n\n")
 
 	bar := progressbar.Default(int64(transactions), "constructing txs")
@@ -44,7 +89,7 @@ func constructTransactions(
 
 		tx := &std.Tx{
 			Msgs: []std.Msg{getMsg(creator, i)},
-			Fee:  defaultDeployTxFee,
+			Fee:  txFee,
 		}
 
 		// Fetch the next account nonce

internal/runtime/package_deployment.go

@@ -20,6 +20,7 @@ func (c *packageDeployment) Initialize(
 	_ std.Account,
 	_ crypto.PrivKey,
 	_ string,
+	_ EstimateGasFn,
 ) ([]*std.Tx, error) {
 	// No extra setup needed for this runtime type
 	return nil, nil
@@ -30,6 +31,7 @@ func (c *packageDeployment) ConstructTransactions(
 	accounts []std.Account,
 	transactions uint64,
 	chainID string,
+	estimateFn EstimateGasFn,
 ) ([]*std.Tx, error) {
 	var (
 		timestamp = time.Now().Unix()
@@ -65,5 +67,6 @@ func (c *packageDeployment) ConstructTransactions(
 		transactions,
 		chainID,
 		getMsgFn,
+		estimateFn,
 	)
 }

internal/runtime/realm_call.go

@@ -8,6 +8,7 @@ import (
 	"github.com/gnolang/gno/gnovm"
 	"github.com/gnolang/gno/tm2/pkg/crypto"
 	"github.com/gnolang/gno/tm2/pkg/std"
+	"github.com/gnolang/supernova/internal/common"
 	"github.com/gnolang/supernova/internal/signer"
 )
 
@@ -21,7 +22,12 @@ func newRealmCall() *realmCall {
 	return &realmCall{}
 }
 
-func (r *realmCall) Initialize(account std.Account, key crypto.PrivKey, chainID string) ([]*std.Tx, error) {
+func (r *realmCall) Initialize(
+	account std.Account,
+	key crypto.PrivKey,
+	chainID string,
+	estimateFn EstimateGasFn,
+) ([]*std.Tx, error) {
 	// The Realm needs to be deployed before
 	// it can be interacted with
 	r.realmPath = fmt.Sprintf(
@@ -62,6 +68,25 @@ func (r *realmCall) Initialize(account std.Account, key crypto.PrivKey, chainID
 		return nil, fmt.Errorf("unable to sign initialize transaction, %w", err)
 	}
 
+	// Estimate the gas for the initial tx
+	gasWanted, err := estimateFn(tx)
+	if err != nil {
+		return nil, fmt.Errorf("unable to estimate gas: %w", err)
+	}
+
+	// Wipe the signatures, because we will change the fee,
+	// and cause the previous ones to be invalid
+	clear(tx.Signatures)
+
+	tx.Fee = std.NewFee(
+		gasWanted+10_000, // buffer with 10k gas
+		common.DefaultGasFee,
+	)
+
+	if err = signer.SignTx(tx, key, cfg); err != nil {
+		return nil, fmt.Errorf("unable to sign initialize transaction, %w", err)
+	}
+
 	return []*std.Tx{tx}, nil
 }
 
@@ -70,6 +95,7 @@ func (r *realmCall) ConstructTransactions(
 	accounts []std.Account,
 	transactions uint64,
 	chainID string,
+	estimateFn EstimateGasFn,
 ) ([]*std.Tx, error) {
 	getMsgFn := func(creator std.Account, index int) std.Msg {
 		return vm.MsgCall{
@@ -86,5 +112,6 @@ func (r *realmCall) ConstructTransactions(
 		transactions,
 		chainID,
 		getMsgFn,
+		estimateFn,
 	)
 }

internal/runtime/realm_deployment.go

@@ -20,6 +20,7 @@ func (c *realmDeployment) Initialize(
 	_ std.Account,
 	_ crypto.PrivKey,
 	_ string,
+	_ EstimateGasFn,
 ) ([]*std.Tx, error) {
 	// No extra setup needed for this runtime type
 	return nil, nil
@@ -30,6 +31,7 @@ func (c *realmDeployment) ConstructTransactions(
 	accounts []std.Account,
 	transactions uint64,
 	chainID string,
+	estimateFn EstimateGasFn,
 ) ([]*std.Tx, error) {
 	var (
 		timestamp = time.Now().Unix()
@@ -65,5 +67,6 @@ func (c *realmDeployment) ConstructTransactions(
 		transactions,
 		chainID,
 		getMsgFn,
+		estimateFn,
 	)
 }

internal/runtime/runtime.go

@@ -11,7 +11,10 @@ const (
 	packagePathPrefix = "gno.land/p"
 )
 
-var defaultDeployTxFee = std.NewFee(500000, common.DefaultGasFee)
+var defaultDeployTxFee = std.NewFee(1_000_000_000, common.DefaultGasFee)
+
+// EstimateGasFn is the gas estimation callback
+type EstimateGasFn func(tx *std.Tx) (int64, error)
 
 // Runtime is the base interface for all runtime
 // implementations.
@@ -25,6 +28,7 @@ type Runtime interface {
 		account std.Account,
 		key crypto.PrivKey,
 		chainID string,
+		estimateFn EstimateGasFn,
 	) ([]*std.Tx, error)
 
 	// ConstructTransactions generates and signs the required transactions
@@ -34,6 +38,7 @@ type Runtime interface {
 		accounts []std.Account,
 		transactions uint64,
 		chainID string,
+		estimateFn EstimateGasFn,
 	) ([]*std.Tx, error)
 }