change: move handling of tx fees and inflationary rewards to middlewares

app/ante.go

@@ -59,7 +59,8 @@ func NewAnteHandler(options HandlerOptions) (sdk.AnteHandler, error) {
 		ante.NewTxTimeoutHeightDecorator(),
 		ante.NewValidateMemoDecorator(options.AccountKeeper),
 		ante.NewConsumeGasForTxSizeDecorator(options.AccountKeeper),
-		ante.NewDeductFeeDecorator(options.AccountKeeper, options.BankKeeper, options.FeegrantKeeper),
+		// custom archway fee deduction, which splits fees between gastracker and auths fee collector
+		gastrackerante.NewDeductFeeDecorator(options.AccountKeeper, options.BankKeeper, options.FeegrantKeeper, options.GasTrackingKeeper),
 		// SetPubKeyDecorator must be called before all signature verification decorators
 		ante.NewSetPubKeyDecorator(options.AccountKeeper),
 		ante.NewValidateSigCountDecorator(options.AccountKeeper),

app/app.go

@@ -2,6 +2,7 @@ package app
 
 import (
 	"fmt"
+	"github.com/archway-network/archway/x/gastracker/mintbankkeeper"
 	"io"
 	"net/http"
 	"os"
@@ -368,15 +369,6 @@ func NewArchwayApp(
 		app.bankKeeper,
 		app.getSubspace(stakingtypes.ModuleName),
 	)
-	app.mintKeeper = mintkeeper.NewKeeper(
-		appCodec,
-		keys[minttypes.StoreKey],
-		app.getSubspace(minttypes.ModuleName),
-		&stakingKeeper,
-		app.accountKeeper,
-		app.bankKeeper,
-		authtypes.FeeCollectorName,
-	)
 	app.distrKeeper = distrkeeper.NewKeeper(
 		appCodec,
 		keys[distrtypes.StoreKey],
@@ -505,6 +497,17 @@ func NewArchwayApp(
 		app.mintKeeper,
 	)
 
+	// note we set up mint keeper after gastracking keeper
+	app.mintKeeper = mintkeeper.NewKeeper(
+		appCodec,
+		keys[minttypes.StoreKey],
+		app.getSubspace(minttypes.ModuleName),
+		&stakingKeeper,
+		app.accountKeeper,
+		mintbankkeeper.NewKeeper(app.bankKeeper, app.gastrackingKeeper),
+		authtypes.FeeCollectorName,
+	)
+
 	// Setting gas recorder here to avoid cyclic loop
 	trackingWasmVm.SetGasRecorder(app.gastrackingKeeper)
 

x/gastracker/ante/fee_deduction.go

@@ -0,0 +1,108 @@
+package ante
+
+import (
+	"fmt"
+	"github.com/archway-network/archway/x/gastracker"
+	"github.com/archway-network/archway/x/gastracker/common"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
+	"github.com/cosmos/cosmos-sdk/x/auth/ante"
+	"github.com/cosmos/cosmos-sdk/x/auth/types"
+)
+
+// 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                ante.AccountKeeper
+	bankKeeper        types.BankKeeper
+	feegrantKeeper    ante.FeegrantKeeper
+	gasTrackingKeeper GasTrackingKeeper
+}
+
+func NewDeductFeeDecorator(ak ante.AccountKeeper, bk types.BankKeeper, fk ante.FeegrantKeeper, gt GasTrackingKeeper) DeductFeeDecorator {
+	return DeductFeeDecorator{
+		ak:                ak,
+		bankKeeper:        bk,
+		feegrantKeeper:    fk,
+		gasTrackingKeeper: gt,
+	}
+}
+
+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 := feeTx.GetFee()
+	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 !feeTx.GetFee().IsZero() {
+		err = DeductFees(dfd.bankKeeper, dfd.gasTrackingKeeper, ctx, deductFeesFromAcc, feeTx.GetFee())
+		if err != nil {
+			return ctx, err
+		}
+	}
+
+	events := sdk.Events{sdk.NewEvent(sdk.EventTypeTx,
+		sdk.NewAttribute(sdk.AttributeKeyFee, feeTx.GetFee().String()),
+	)}
+	ctx.EventManager().EmitEvents(events)
+
+	return next(ctx, tx, simulate)
+}
+
+// DeductFees deducts fees from the given account.
+// NOTE: this is the only logic being changed
+func DeductFees(bankKeeper types.BankKeeper, gt GasTrackingKeeper, ctx sdk.Context, acc types.AccountI, fees sdk.Coins) error {
+	if !fees.IsValid() {
+		return sdkerrors.Wrapf(sdkerrors.ErrInsufficientFee, "invalid fee amount: %s", fees)
+	}
+
+	params := gt.GetParams(ctx)
+
+	authFees, gasTrackerFees := common.SplitCoins(params.DappTxFeeRebateRatio, fees)
+
+	err := bankKeeper.SendCoinsFromAccountToModule(ctx, acc.GetAddress(), types.FeeCollectorName, authFees)
+	if err != nil {
+		return sdkerrors.Wrapf(sdkerrors.ErrInsufficientFunds, err.Error())
+	}
+
+	err = bankKeeper.SendCoinsFromAccountToModule(ctx, acc.GetAddress(), gastracker.ContractRewardCollector, gasTrackerFees)
+	if err != nil {
+		return sdkerrors.Wrapf(sdkerrors.ErrInsufficientFunds, err.Error())
+	}
+
+	return nil
+}

x/gastracker/common/common.go

@@ -0,0 +1,20 @@
+package common
+
+import sdk "github.com/cosmos/cosmos-sdk/types"
+
+func SplitCoins(ratio sdk.Dec, fees sdk.Coins) (authCoins, gasTrackerCoins sdk.Coins) {
+	authCoins = make(sdk.Coins, len(fees))
+	gasTrackerCoins = make(sdk.Coins, len(fees))
+
+	for i, feeCoin := range fees {
+		gasTrackerCoin := sdk.Coin{
+			Denom:  feeCoin.Denom,
+			Amount: feeCoin.Amount.ToDec().Mul(ratio).TruncateInt(),
+		}
+
+		gasTrackerCoins[i] = gasTrackerCoin
+		authCoins[i] = feeCoin.Sub(gasTrackerCoin)
+	}
+
+	return authCoins, gasTrackerCoins
+}

x/gastracker/mintbankkeeper/keeper.go

@@ -0,0 +1,66 @@
+package mintbankkeeper
+
+import (
+	"github.com/archway-network/archway/x/gastracker"
+	"github.com/archway-network/archway/x/gastracker/common"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
+	minttypes "github.com/cosmos/cosmos-sdk/x/mint/types"
+)
+
+var (
+	_ minttypes.BankKeeper = (*Keeper)(nil)
+)
+
+type GasTrackingKeeper interface {
+	GetParams(ctx sdk.Context) gastracker.Params
+}
+
+func NewKeeper(bk minttypes.BankKeeper, gtk GasTrackingKeeper) Keeper {
+	return Keeper{
+		bk:  bk,
+		gtk: gtk,
+	}
+}
+
+// Keeper mocks the behaviour of the bank keeper required
+// by the mint module and splits inflationary rewards
+// between the gas tracking module and auth's fee collector
+type Keeper struct {
+	bk  minttypes.BankKeeper
+	gtk GasTrackingKeeper
+}
+
+// SendCoinsFromModuleToModule overrides the behaviour of mint's BankKeeper and redirects part of inflationary
+// rewards towards the gastracker module.
+func (k Keeper) SendCoinsFromModuleToModule(ctx sdk.Context, senderModule, recipientModule string, amt sdk.Coins) error {
+	// we only care about this if the recipient is fee collector
+	// (which for instance is always the case)
+	if recipientModule != authtypes.FeeCollectorName {
+		return k.bk.SendCoinsFromModuleToModule(ctx, senderModule, recipientModule, amt)
+	}
+
+	ratio := k.gtk.GetParams(ctx).DappInflationRewardsRatio
+	stakingRewards, dappRewards := common.SplitCoins(ratio, amt)
+
+	// send to auth's fee collector
+	err := k.bk.SendCoinsFromModuleToModule(ctx, senderModule, recipientModule, stakingRewards)
+	if err != nil {
+		return err
+	}
+	// send to gastracker
+	err = k.bk.SendCoinsFromModuleToModule(ctx, senderModule, gastracker.ContractRewardCollector, dappRewards)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (k Keeper) SendCoinsFromModuleToAccount(ctx sdk.Context, senderModule string, recipientAddr sdk.AccAddress, amt sdk.Coins) error {
+	return k.bk.SendCoinsFromModuleToAccount(ctx, senderModule, recipientAddr, amt)
+}
+
+func (k Keeper) MintCoins(ctx sdk.Context, name string, amt sdk.Coins) error {
+	return k.bk.MintCoins(ctx, name, amt)
+}

x/gastracker/module/abci.go

@@ -5,7 +5,6 @@ import (
 
 	"github.com/cosmos/cosmos-sdk/telemetry"
 	sdk "github.com/cosmos/cosmos-sdk/types"
-	authTypes "github.com/cosmos/cosmos-sdk/x/auth/types"
 	mintTypes "github.com/cosmos/cosmos-sdk/x/mint/types"
 	abci "github.com/tendermint/tendermint/abci/types"
 
@@ -15,7 +14,6 @@ import (
 
 type RewardTransferKeeper interface {
 	SendCoinsFromModuleToAccount(ctx sdk.Context, senderModule string, recipientAddr sdk.AccAddress, amt sdk.Coins) error
-	SendCoinsFromModuleToModule(ctx sdk.Context, senderModule, recipientModule string, amt sdk.Coins) error
 }
 
 type MintParamsKeeper interface {
@@ -48,16 +46,6 @@ func BeginBlock(context sdk.Context, _ abci.RequestBeginBlock, gasTrackingKeeper
 		return
 	}
 
-	totalFeeToBeCollected := make(sdk.Coins, len(totalContractRewardsPerBlock))
-	for i := range totalFeeToBeCollected {
-		totalFeeToBeCollected[i] = sdk.NewCoin(totalContractRewardsPerBlock[i].Denom, totalContractRewardsPerBlock[i].Amount.Ceil().RoundInt())
-	}
-
-	err := rewardTransferKeeper.SendCoinsFromModuleToModule(context, authTypes.FeeCollectorName, gstTypes.ContractRewardCollector, totalFeeToBeCollected)
-	if err != nil {
-		panic(err)
-	}
-
 	distributeRewards(context, rewardAddresses, rewardsByAddress, gasTrackingKeeper, rewardTransferKeeper)
 }
 

x/gastracker/module/abci_test.go

@@ -5,7 +5,6 @@ import (
 	gstTypes "github.com/archway-network/archway/x/gastracker"
 	"github.com/archway-network/archway/x/gastracker/testutil"
 	sdk "github.com/cosmos/cosmos-sdk/types"
-	authTypes "github.com/cosmos/cosmos-sdk/x/auth/types"
 	mintTypes "github.com/cosmos/cosmos-sdk/x/mint/types"
 	"github.com/stretchr/testify/require"
 	"github.com/tendermint/tendermint/abci/types"
@@ -268,7 +267,6 @@ func TestRewardCalculation(t *testing.T) {
 			sdk.NewDecCoinFromDec("test1", sdk.MustNewDecFromStr("0.683333333333333333")),
 		},
 		logs: []*RewardTransferKeeperCallLogs{
-			createLogModule(authTypes.FeeCollectorName, gstTypes.ContractRewardCollector, sdk.NewCoins(sdk.NewCoin("test", sdk.NewInt(3)), sdk.NewCoin("test1", sdk.NewInt(1)))),
 			createLogAddr(gstTypes.ContractRewardCollector, spareAddress[5].String(), sdk.NewCoins()),
 			createLogAddr(gstTypes.ContractRewardCollector, spareAddress[6].String(), sdk.NewCoins(sdk.NewCoin("test", sdk.NewInt(2)))),
 		},
@@ -394,9 +392,6 @@ func TestRewardCalculation(t *testing.T) {
 	}
 }
 
-//func TestRewardCalculation(t *testing.T) {
-//}
-
 func TestContractRewardsWithoutContractPremium(t *testing.T) {
 	config := sdk.GetConfig()
 	config.SetBech32PrefixForAccount("archway", "archway")
@@ -422,7 +417,6 @@ func TestContractRewardsWithoutContractPremium(t *testing.T) {
 			sdk.NewDecCoinFromDec("test1", sdk.MustNewDecFromStr("0.666666666666666666")),
 		},
 		logs: []*RewardTransferKeeperCallLogs{
-			createLogModule(authTypes.FeeCollectorName, gstTypes.ContractRewardCollector, sdk.NewCoins(sdk.NewCoin("test", sdk.NewInt(3)), sdk.NewCoin("test1", sdk.NewInt(1)))),
 			createLogAddr(gstTypes.ContractRewardCollector, spareAddress[5].String(), sdk.NewCoins()),
 			createLogAddr(gstTypes.ContractRewardCollector, spareAddress[6].String(), sdk.NewCoins(sdk.NewCoin("test", sdk.NewInt(2)))),
 		},
@@ -571,7 +565,6 @@ func TestContractRewardsWithoutDappInflation(t *testing.T) {
 			sdk.NewDecCoinFromDec("test1", sdk.MustNewDecFromStr("0.683333333333333333")),
 		},
 		logs: []*RewardTransferKeeperCallLogs{
-			createLogModule(authTypes.FeeCollectorName, gstTypes.ContractRewardCollector, sdk.NewCoins(sdk.NewCoin("test", sdk.NewInt(3)), sdk.NewCoin("test1", sdk.NewInt(1)))),
 			createLogAddr(gstTypes.ContractRewardCollector, spareAddress[5].String(), sdk.NewCoins()),
 			createLogAddr(gstTypes.ContractRewardCollector, spareAddress[6].String(), sdk.NewCoins(sdk.NewCoin("test", sdk.NewInt(2)))),
 		},
@@ -719,7 +712,6 @@ func TestContractRewardsWithoutGasRebate(t *testing.T) {
 			sdk.NewDecCoinFromDec("test", sdk.MustNewDecFromStr("0.005355")),
 		},
 		logs: []*RewardTransferKeeperCallLogs{
-			createLogModule(authTypes.FeeCollectorName, gstTypes.ContractRewardCollector, sdk.NewCoins(sdk.NewCoin("test", sdk.NewInt(1)))),
 			createLogAddr(gstTypes.ContractRewardCollector, spareAddress[5].String(), sdk.NewCoins()),
 			createLogAddr(gstTypes.ContractRewardCollector, spareAddress[6].String(), sdk.NewCoins()),
 		},
@@ -1137,7 +1129,6 @@ func TestContractRewardsWithoutGasRebateToUser(t *testing.T) {
 			sdk.NewDecCoinFromDec("test1", sdk.MustNewDecFromStr("0.683333333333333333")),
 		},
 		logs: []*RewardTransferKeeperCallLogs{
-			createLogModule(authTypes.FeeCollectorName, gstTypes.ContractRewardCollector, sdk.NewCoins(sdk.NewCoin("test", sdk.NewInt(3)), sdk.NewCoin("test1", sdk.NewInt(1)))),
 			createLogAddr(gstTypes.ContractRewardCollector, spareAddress[5].String(), sdk.NewCoins()),
 			createLogAddr(gstTypes.ContractRewardCollector, spareAddress[6].String(), sdk.NewCoins(sdk.NewCoin("test", sdk.NewInt(2)))),
 		},