Merge pull request #202 from stratosnet/qb1582_gas-prices_flag_suppor…

…t_all_denoms

Fix/QB-1582: Gwei/Stos denom not working with gas-price flag

app/ante/fee.go

@@ -0,0 +1,149 @@
+package ante
+
+import (
+	"fmt"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
+	"github.com/cosmos/cosmos-sdk/x/auth/types"
+)
+
+// MempoolFeeDecorator will check if the transaction's fee is at least as large
+// as the local validator's minimum gasFee (defined in validator config).
+// If fee is too low, decorator returns error and tx is rejected from mempool.
+// Note this only applies when ctx.CheckTx = true
+// If fee is high enough or not CheckTx, then call next AnteHandler
+// CONTRACT: Tx must implement FeeTx to use MempoolFeeDecorator
+type MempoolFeeDecorator struct{}
+
+func NewMempoolFeeDecorator() MempoolFeeDecorator {
+	return MempoolFeeDecorator{}
+}
+
+func (mfd MempoolFeeDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (newCtx sdk.Context, err error) {
+	feeTx, ok := tx.(sdk.FeeTx)
+	if !ok {
+		return ctx, sdkerrors.Wrap(sdkerrors.ErrTxDecode, "Tx must be a FeeTx")
+	}
+
+	feeCoins, err := sdk.ParseCoinsNormalized(feeTx.GetFee().String())
+	if err != nil {
+		return ctx, sdkerrors.Wrapf(sdkerrors.ErrInsufficientFee, "fee parsing error: %s", feeCoins)
+	}
+	gas := feeTx.GetGas()
+
+	// Ensure that the provided fees meet a minimum threshold for the validator,
+	// if this is a CheckTx. This is only for local mempool purposes, and thus
+	// is only ran on check tx.
+	if ctx.IsCheckTx() && !simulate {
+		minGasPrices := ctx.MinGasPrices()
+		if !minGasPrices.IsZero() {
+			requiredFees := make(sdk.Coins, len(minGasPrices))
+
+			// Determine the required fees by multiplying each required minimum gas
+			// price by the gas limit, where fee = ceil(minGasPrice * gasLimit).
+			glDec := sdk.NewDec(int64(gas))
+			for i, gp := range minGasPrices {
+				fee := gp.Amount.Mul(glDec)
+				requiredFees[i] = sdk.NewCoin(gp.Denom, fee.Ceil().RoundInt())
+			}
+
+			if !feeCoins.IsAnyGTE(requiredFees) {
+				return ctx, sdkerrors.Wrapf(sdkerrors.ErrInsufficientFee, "insufficient fees; got: %s required: %s", feeCoins, requiredFees)
+			}
+		}
+	}
+
+	return next(ctx, tx, simulate)
+}
+
+// DeductFeeDecorator deducts fees from the first signer of the tx
+// If the first signer does not have the funds to pay for the fees, return with InsufficientFunds error
+// Call next AnteHandler if fees successfully deducted
+// CONTRACT: Tx must implement FeeTx interface to use DeductFeeDecorator
+type DeductFeeDecorator struct {
+	ak             AccountKeeper
+	bankKeeper     types.BankKeeper
+	feegrantKeeper FeegrantKeeper
+}
+
+func NewDeductFeeDecorator(ak AccountKeeper, bk types.BankKeeper, fk FeegrantKeeper) DeductFeeDecorator {
+	return DeductFeeDecorator{
+		ak:             ak,
+		bankKeeper:     bk,
+		feegrantKeeper: fk,
+	}
+}
+
+func (dfd DeductFeeDecorator) AnteHandle(ctx sdk.Context, tx sdk.Tx, simulate bool, next sdk.AnteHandler) (newCtx sdk.Context, err error) {
+	feeTx, ok := tx.(sdk.FeeTx)
+	if !ok {
+		return ctx, sdkerrors.Wrap(sdkerrors.ErrTxDecode, "Tx must be a FeeTx")
+	}
+
+	if addr := dfd.ak.GetModuleAddress(types.FeeCollectorName); addr == nil {
+		return ctx, fmt.Errorf("fee collector module account (%s) has not been set", types.FeeCollectorName)
+	}
+
+	fee, err := sdk.ParseCoinsNormalized(feeTx.GetFee().String())
+	if err != nil {
+		return ctx, sdkerrors.Wrapf(sdkerrors.ErrInsufficientFee, "fee parsing error: %s", fee)
+	}
+	feePayer := feeTx.FeePayer()
+	feeGranter := feeTx.FeeGranter()
+
+	deductFeesFrom := feePayer
+
+	// if feegranter set deduct fee from feegranter account.
+	// this works with only when feegrant enabled.
+	if feeGranter != nil {
+		if dfd.feegrantKeeper == nil {
+			return ctx, sdkerrors.Wrap(sdkerrors.ErrInvalidRequest, "fee grants are not enabled")
+		} else if !feeGranter.Equals(feePayer) {
+			err := dfd.feegrantKeeper.UseGrantedFees(ctx, feeGranter, feePayer, fee, tx.GetMsgs())
+			if err != nil {
+				return ctx, sdkerrors.Wrapf(err, "%s not allowed to pay fees from %s", feeGranter, feePayer)
+			}
+		}
+
+		deductFeesFrom = feeGranter
+	}
+
+	deductFeesFromAcc := dfd.ak.GetAccount(ctx, deductFeesFrom)
+	if deductFeesFromAcc == nil {
+		return ctx, sdkerrors.Wrapf(sdkerrors.ErrUnknownAddress, "fee payer address: %s does not exist", deductFeesFrom)
+	}
+
+	// deduct the fees
+	if !fee.IsZero() {
+		err = DeductFees(dfd.bankKeeper, ctx, deductFeesFromAcc, fee)
+		if err != nil {
+			return ctx, err
+		}
+	}
+
+	events := sdk.Events{
+		sdk.NewEvent(
+			sdk.EventTypeTx,
+			sdk.NewAttribute(sdk.AttributeKeyFee, fee.String()),
+			sdk.NewAttribute(sdk.AttributeKeyFeePayer, deductFeesFrom.String()),
+		),
+	}
+	ctx.EventManager().EmitEvents(events)
+
+	return next(ctx, tx, simulate)
+}
+
+// DeductFees deducts fees from the given account.
+func DeductFees(bankKeeper types.BankKeeper, ctx sdk.Context, acc types.AccountI, fees sdk.Coins) error {
+	if !fees.IsValid() {
+		return sdkerrors.Wrapf(sdkerrors.ErrInsufficientFee, "invalid fee amount: %s", fees)
+	}
+
+	err := bankKeeper.SendCoinsFromAccountToModule(ctx, acc.GetAddress(), types.FeeCollectorName, fees)
+	if err != nil {
+		return sdkerrors.Wrapf(sdkerrors.ErrInsufficientFunds, err.Error())
+	}
+
+	return nil
+}

app/ante/handler_options.go

@@ -61,12 +61,12 @@ func newCosmosAnteHandler(options HandlerOptions) sdk.AnteHandler {
 		RejectMessagesDecorator{}, // reject MsgEthereumTxs
 		ante.NewSetUpContextDecorator(),
 		ante.NewRejectExtensionOptionsDecorator(),
-		ante.NewMempoolFeeDecorator(),
+		NewMempoolFeeDecorator(),
 		ante.NewValidateBasicDecorator(),
 		ante.NewTxTimeoutHeightDecorator(),
 		ante.NewValidateMemoDecorator(options.AccountKeeper),
 		ante.NewConsumeGasForTxSizeDecorator(options.AccountKeeper),
-		ante.NewDeductFeeDecorator(options.AccountKeeper, options.BankKeeper, options.FeegrantKeeper),
+		NewDeductFeeDecorator(options.AccountKeeper, options.BankKeeper, options.FeegrantKeeper),
 		// SetPubKeyDecorator must be called before all signature verification decorators
 		ante.NewSetPubKeyDecorator(options.AccountKeeper),
 		ante.NewValidateSigCountDecorator(options.AccountKeeper),

app/ante/interfaces.go

@@ -5,6 +5,7 @@ import (
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/cosmos/cosmos-sdk/types/tx"
+	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core"
@@ -15,6 +16,20 @@ import (
 	evmtypes "github.com/stratosnet/stratos-chain/x/evm/types"
 )
 
+// AccountKeeper defines the contract needed for AccountKeeper related APIs.
+// Interface provides support to use non-sdk AccountKeeper for AnteHandler's decorators.
+type AccountKeeper interface {
+	GetParams(ctx sdk.Context) (params authtypes.Params)
+	GetAccount(ctx sdk.Context, addr sdk.AccAddress) authtypes.AccountI
+	SetAccount(ctx sdk.Context, acc authtypes.AccountI)
+	GetModuleAddress(moduleName string) sdk.AccAddress
+}
+
+// FeegrantKeeper defines the expected feegrant keeper.
+type FeegrantKeeper interface {
+	UseGrantedFees(ctx sdk.Context, granter, grantee sdk.AccAddress, fee sdk.Coins, msgs []sdk.Msg) error
+}
+
 // EVMKeeper defines the expected keeper interface used on the Eth AnteHandler
 type EVMKeeper interface {
 	statedb.Keeper