fix(gasless): usage identifier validation and mapping to gas tank IDs

x/gasless/keeper/fee_helper.go

@@ -1,13 +1,17 @@
 package keeper
 
 import (
+	"errors"
+	"fmt"
+	"slices"
 	"strconv"
 	"strings"
 
+	"cosmossdk.io/collections"
 	sdkerrors "cosmossdk.io/errors"
 	sdkmath "cosmossdk.io/math"
 	sdk "github.com/cosmos/cosmos-sdk/types"
-	"github.com/dymensionxyz/dymension-rdk/utils/sliceutils"
+
 	"github.com/dymensionxyz/dymension-rdk/x/gasless/types"
 )
 
@@ -144,10 +148,36 @@ func (k Keeper) GetFeeSource(ctx sdk.Context, sdkTx sdk.Tx, originalFeePayer sdk
 		err              error
 	)
 
+	lastUsedID, err := k.LastUsedGasTankID(ctx, usageIdentifier)
+	if err != nil {
+		if !errors.Is(err, collections.ErrNotFound) {
+			k.EmitFeeConsumptionEvent(ctx, originalFeePayer, []uint64{}, []error{fmt.Errorf("last used gas tank ID: %w", err)}, 0)
+			return originalFeePayer
+		}
+	}
+
 	gasTankIds := usageIdentifierToGasTankIds.GasTankIds
-	for _, gtid := range gasTankIds {
+	var startIndex int
+	index := slices.Index(gasTankIds, lastUsedID)
+	if index == -1 {
+		startIndex = 0
+	} else {
+		startIndex = (index + 1) % len(gasTankIds)
+	}
+
+	n := len(gasTankIds)
+	for i := 0; i < n; i++ {
+		idx := (startIndex + i) % n
+		gtid := gasTankIds[idx]
+
 		gasTank, isValid, err = k.CanGasTankBeUsedAsSource(ctx, gtid, tempConsumer, fee)
 		if isValid {
+			// update the last used GasTankID
+			err = k.lastUsedGasTankIDMap.Set(ctx, usageIdentifier, gtid)
+			if err != nil {
+				k.EmitFeeConsumptionEvent(ctx, originalFeePayer, failedGtids, []error{fmt.Errorf("update last used gas tank ID: %w", err)}, gtid)
+				return originalFeePayer
+			}
 			break
 		}
 		failedGtidErrors = append(failedGtidErrors, err)
@@ -191,11 +221,11 @@ func (k Keeper) GetFeeSource(ctx sdk.Context, sdkTx sdk.Tx, originalFeePayer sdk
 	gasConsumer.Consumptions[consumptionIndex].Usage = existingUsage
 	k.SetGasConsumer(ctx, gasConsumer)
 
-	// Move the used gas tank to the end of the list of all gas tanks. This ensures that in the next cycle,
-	// a different gas tank can be selected for the same usage identifier if available,
-	// spreading out the usage of fees across different tanks.
-	usageIdentifierToGasTankIds.GasTankIds = sliceutils.ShiftValueToEnd(usageIdentifierToGasTankIds.GasTankIds, gasTank.Id)
-	k.SetUsageIdentifierToGasTankIds(ctx, usageIdentifierToGasTankIds)
+	// Update the last used GasTankID for the UsageIdentifier
+	if err = k.lastUsedGasTankIDMap.Set(ctx, usageIdentifier, gasTank.Id); err != nil {
+		k.EmitFeeConsumptionEvent(ctx, originalFeePayer, failedGtids, []error{fmt.Errorf("update last used gas tank ID: %w", err)}, gasTank.Id)
+		return originalFeePayer
+	}
 
 	feeSource := gasTank.GetGasTankReserveAddress()
 	k.EmitFeeConsumptionEvent(ctx, feeSource, failedGtids, failedGtidErrors, gasTank.Id)

x/gasless/keeper/gasless.go

@@ -6,7 +6,8 @@ import (
 
 	sdkerrors "cosmossdk.io/errors"
 	sdk "github.com/cosmos/cosmos-sdk/types"
-	errors "github.com/cosmos/cosmos-sdk/types/errors"
+	"github.com/cosmos/cosmos-sdk/types/errors"
+
 	"github.com/dymensionxyz/dymension-rdk/utils/sliceutils"
 	"github.com/dymensionxyz/dymension-rdk/x/gasless/types"
 )
@@ -95,7 +96,9 @@ func (k Keeper) CreateGasTank(ctx sdk.Context, msg *types.MsgCreateGasTank) (typ
 		return types.GasTank{}, err
 	}
 
-	k.AddGasTankIdToUsageIdentifiers(ctx, gasTank.UsageIdentifiers, gasTank.Id)
+	if err := k.AddGasTankIdToUsageIdentifiers(ctx, gasTank.UsageIdentifiers, gasTank.Id); err != nil {
+		return types.GasTank{}, err
+	}
 	k.SetGasTank(ctx, gasTank)
 
 	ctx.EventManager().EmitEvents(sdk.Events{
@@ -165,7 +168,6 @@ func (k Keeper) ValidateMsgUpdateGasTankConfig(ctx sdk.Context, msg *types.MsgUp
 			if !k.IsValidUsageIdentifier(ctx, identifier) {
 				return sdkerrors.Wrapf(errors.ErrInvalidRequest, "invalid usage identifier - %s", identifier)
 			}
-
 		}
 	}
 
@@ -183,7 +185,9 @@ func (k Keeper) UpdateGasTankConfig(ctx sdk.Context, msg *types.MsgUpdateGasTank
 	if !gasTank.MaxFeeUsagePerConsumer.Equal(msg.MaxFeeUsagePerConsumer) {
 		consumerUpdateRequire = true
 	}
-	k.RemoveGasTankIdFromUsageIdentifiers(ctx, gasTank.UsageIdentifiers, gasTank.Id)
+	if err := k.RemoveGasTankIdFromUsageIdentifiers(ctx, gasTank.UsageIdentifiers, gasTank.Id); err != nil {
+		return gasTank, err
+	}
 
 	gasTank.MaxFeeUsagePerTx = msg.MaxFeeUsagePerTx
 	gasTank.MaxFeeUsagePerConsumer = msg.MaxFeeUsagePerConsumer
@@ -193,7 +197,9 @@ func (k Keeper) UpdateGasTankConfig(ctx sdk.Context, msg *types.MsgUpdateGasTank
 	if consumerUpdateRequire {
 		k.UpdateConsumerAllowance(ctx, gasTank)
 	}
-	k.AddGasTankIdToUsageIdentifiers(ctx, gasTank.UsageIdentifiers, gasTank.Id)
+	if err := k.AddGasTankIdToUsageIdentifiers(ctx, gasTank.UsageIdentifiers, gasTank.Id); err != nil {
+		return gasTank, err
+	}
 
 	k.SetGasTank(ctx, gasTank)
 

x/gasless/keeper/gasless_test.go

@@ -4,11 +4,10 @@ import (
 	sdkerrors "cosmossdk.io/errors"
 	sdkmath "cosmossdk.io/math"
 	sdk "github.com/cosmos/cosmos-sdk/types"
-	errors "github.com/cosmos/cosmos-sdk/types/errors"
-	"github.com/dymensionxyz/dymension-rdk/x/gasless/types"
-
-	// _ "github.com/stretchr/testify/suite"
+	"github.com/cosmos/cosmos-sdk/types/errors"
 	"golang.org/x/exp/slices"
+
+	"github.com/dymensionxyz/dymension-rdk/x/gasless/types"
 )
 
 func (s *KeeperTestSuite) TestCreateGasTank() {

x/gasless/keeper/genesis.go

@@ -15,7 +15,9 @@ func (k Keeper) InitGenesis(ctx sdk.Context, genState types.GenesisState) {
 	k.SetParams(ctx, genState.Params)
 
 	for _, uigids := range genState.UsageIdentifierToGastankIds {
-		k.SetUsageIdentifierToGasTankIds(ctx, uigids)
+		if err := k.SetUsageIdentifierToGasTankIds(ctx, uigids); err != nil {
+			panic(err)
+		}
 	}
 
 	k.SetLastGasTankID(ctx, genState.LastGasTankId)
@@ -31,9 +33,13 @@ func (k Keeper) InitGenesis(ctx sdk.Context, genState types.GenesisState) {
 
 // ExportGenesis returns the capability module's exported genesis.
 func (k Keeper) ExportGenesis(ctx sdk.Context) *types.GenesisState {
+	gasTankIds, err := k.GetAllUsageIdentifierToGasTankIds(ctx)
+	if err != nil {
+		panic(err)
+	}
 	return &types.GenesisState{
 		Params:                      k.GetParams(ctx),
-		UsageIdentifierToGastankIds: k.GetAllUsageIdentifierToGasTankIds(ctx),
+		UsageIdentifierToGastankIds: gasTankIds,
 		LastGasTankId:               k.GetLastGasTankID(ctx),
 		GasTanks:                    k.GetAllGasTanks(ctx),
 		GasConsumers:                k.GetAllGasConsumers(ctx),

x/gasless/keeper/grpc_query.go

@@ -7,9 +7,10 @@ import (
 	sdk "github.com/cosmos/cosmos-sdk/types"
 
 	"github.com/cosmos/cosmos-sdk/types/query"
-	"github.com/dymensionxyz/dymension-rdk/x/gasless/types"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
+
+	"github.com/dymensionxyz/dymension-rdk/x/gasless/types"
 )
 
 // Querier is used as Keeper will have duplicate methods if used directly, and gRPC names take precedence over keeper.
@@ -211,11 +212,15 @@ func (k Querier) GasConsumersByGasTankID(goCtx context.Context, req *types.Query
 
 func (k Querier) GasTankIdsForAllUsageIdentifiers(goCtx context.Context, _ *types.QueryGasTankIdsForAllUsageIdentifiersRequest) (*types.QueryGasTankIdsForAllUsageIdentifiersResponse, error) {
 	ctx := sdk.UnwrapSDKContext(goCtx)
-	usageIdentifierToGasTankIds := []*types.UsageIdentifierToGasTankIds{}
-	allusageIdentifierToGasTankIds := k.GetAllUsageIdentifierToGasTankIds(ctx)
-	for _, val := range allusageIdentifierToGasTankIds {
+	allUsageIdentifierToGasTankIds, err := k.GetAllUsageIdentifierToGasTankIds(ctx)
+	if err != nil {
+		return nil, status.Error(codes.Internal, err.Error())
+	}
+
+	var usageIdentifierToGasTankIds = make([]*types.UsageIdentifierToGasTankIds, len(allUsageIdentifierToGasTankIds))
+	for i, val := range allUsageIdentifierToGasTankIds {
 		gtids := val
-		usageIdentifierToGasTankIds = append(usageIdentifierToGasTankIds, &gtids)
+		usageIdentifierToGasTankIds[i] = &gtids
 	}
 	return &types.QueryGasTankIdsForAllUsageIdentifiersResponse{
 		UsageIdentifierToGastankIds: usageIdentifierToGasTankIds,

x/gasless/keeper/keeper.go

@@ -3,6 +3,7 @@ package keeper
 import (
 	"fmt"
 
+	"cosmossdk.io/collections"
 	"github.com/cosmos/cosmos-sdk/codec"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	paramstypes "github.com/cosmos/cosmos-sdk/x/params/types"
@@ -11,6 +12,8 @@ import (
 	wasmkeeper "github.com/CosmWasm/wasmd/x/wasm/keeper"
 	codectypes "github.com/cosmos/cosmos-sdk/codec/types"
 	storetypes "github.com/cosmos/cosmos-sdk/store/types"
+
+	"github.com/dymensionxyz/dymension-rdk/utils/collcompat"
 	"github.com/dymensionxyz/dymension-rdk/x/gasless/types"
 )
 
@@ -24,6 +27,9 @@ type Keeper struct {
 	// accountKeeper types.AccountKeeper
 	bankKeeper types.BankKeeper
 	wasmKeeper *wasmkeeper.Keeper
+
+	usageIdentifierToGasTankIDSet collections.KeySet[collections.Pair[string, uint64]]
+	lastUsedGasTankIDMap          collections.Map[string, uint64]
 }
 
 // NewKeeper creates a new gasless Keeper instance.
@@ -46,6 +52,18 @@ func NewKeeper(
 		interfaceRegistry: interfaceRegistry,
 		bankKeeper:        bankKeeper,
 		wasmKeeper:        wasmKeeper,
+		usageIdentifierToGasTankIDSet: collections.NewKeySet[collections.Pair[string, uint64]](
+			collections.NewSchemaBuilder(collcompat.NewKVStoreService(storeKey)),
+			types.UsageIdentifierToGasTankIdsKeyPrefix,
+			"usageIdentifierToGasTankID",
+			collections.PairKeyCodec(collections.StringKey, collections.Uint64Key)),
+		lastUsedGasTankIDMap: collections.NewMap(
+			collections.NewSchemaBuilder(collcompat.NewKVStoreService(storeKey)),
+			types.LastUsedGasTankKey,
+			"lastUsedGasTankID",
+			collections.StringKey,
+			collections.Uint64Value,
+		),
 	}
 }