Implement a Reverse Charge tax approach

app/app.go

@@ -59,6 +59,9 @@ import (
 	v8_2 "github.com/classic-terra/core/v3/app/upgrades/v8_2"
 	v8_3 "github.com/classic-terra/core/v3/app/upgrades/v8_3"
 
+	// v9 had been used by tax2gas and has to be skipped
+	v10 "github.com/classic-terra/core/v3/app/upgrades/v10"
+
 	customante "github.com/classic-terra/core/v3/custom/auth/ante"
 	custompost "github.com/classic-terra/core/v3/custom/auth/post"
 	customauthtx "github.com/classic-terra/core/v3/custom/auth/tx"
@@ -91,6 +94,7 @@ var (
 		v8_1.Upgrade,
 		v8_2.Upgrade,
 		v8_3.Upgrade,
+		v10.Upgrade,
 	}
 
 	// Forks defines forks to be applied to the network
@@ -244,6 +248,7 @@ func NewTerraApp(
 			TXCounterStoreKey:  app.GetKey(wasmtypes.StoreKey),
 			DyncommKeeper:      app.DyncommKeeper,
 			StakingKeeper:      app.StakingKeeper,
+			TaxKeeper:          &app.TaxKeeper,
 			Cdc:                app.appCodec,
 		},
 	)
@@ -253,7 +258,11 @@ func NewTerraApp(
 
 	postHandler, err := custompost.NewPostHandler(
 		custompost.HandlerOptions{
-			DyncommKeeper: app.DyncommKeeper,
+			DyncommKeeper:  app.DyncommKeeper,
+			TaxKeeper:      app.TaxKeeper,
+			BankKeeper:     app.BankKeeper,
+			AccountKeeper:  app.AccountKeeper,
+			TreasuryKeeper: app.TreasuryKeeper,
 		},
 	)
 	if err != nil {
@@ -402,7 +411,7 @@ func (app *TerraApp) RegisterAPIRoutes(apiSvr *api.Server, apiConfig config.APIC
 // RegisterTxService implements the Application.RegisterTxService method.
 func (app *TerraApp) RegisterTxService(clientCtx client.Context) {
 	authtx.RegisterTxService(app.BaseApp.GRPCQueryRouter(), clientCtx, app.BaseApp.Simulate, app.interfaceRegistry)
-	customauthtx.RegisterTxService(app.BaseApp.GRPCQueryRouter(), clientCtx, app.TreasuryKeeper)
+	customauthtx.RegisterTxService(app.BaseApp.GRPCQueryRouter(), clientCtx, app.TreasuryKeeper, app.TaxKeeper)
 }
 
 // RegisterTendermintService implements the Application.RegisterTendermintService method.

app/keepers/keepers.go

@@ -18,6 +18,8 @@ import (
 	ibcexported "github.com/cosmos/ibc-go/v7/modules/core/exported"
 	ibckeeper "github.com/cosmos/ibc-go/v7/modules/core/keeper"
 
+	taxkeeper "github.com/classic-terra/core/v3/x/tax/keeper"
+	taxtypes "github.com/classic-terra/core/v3/x/tax/types"
 	"github.com/cosmos/cosmos-sdk/baseapp"
 	"github.com/cosmos/cosmos-sdk/codec"
 	servertypes "github.com/cosmos/cosmos-sdk/server/types"
@@ -103,6 +105,7 @@ type AppKeepers struct {
 	DyncommKeeper         dyncommkeeper.Keeper
 	IBCHooksKeeper        *ibchookskeeper.Keeper
 	ConsensusParamsKeeper consensusparamkeeper.Keeper
+	TaxKeeper             taxkeeper.Keeper
 
 	Ics20WasmHooks  *ibchooks.WasmHooks
 	IBCHooksWrapper *ibchooks.ICS4Middleware
@@ -156,6 +159,7 @@ func NewAppKeepers(
 		treasurytypes.StoreKey,
 		wasmtypes.StoreKey,
 		dyncommtypes.StoreKey,
+		taxtypes.StoreKey,
 	)
 	tkeys := sdk.NewTransientStoreKeys(paramstypes.TStoreKey)
 	memKeys := sdk.NewMemoryStoreKeys(capabilitytypes.MemStoreKey)
@@ -390,6 +394,7 @@ func NewAppKeepers(
 		appKeepers.BankKeeper,
 		appKeepers.TreasuryKeeper,
 		appKeepers.AccountKeeper,
+		appKeepers.TaxKeeper,
 		appCodec,
 		appKeepers.TransferKeeper,
 	)
@@ -457,6 +462,15 @@ func NewAppKeepers(
 		),
 	)
 
+	appKeepers.TaxKeeper = taxkeeper.NewKeeper(
+		appCodec,
+		appKeepers.keys[taxtypes.StoreKey],
+		appKeepers.BankKeeper,
+		appKeepers.TreasuryKeeper,
+		appKeepers.DistrKeeper,
+		authtypes.NewModuleAddress(govtypes.ModuleName).String(),
+	)
+
 	appKeepers.DyncommKeeper = dyncommkeeper.NewKeeper(
 		appCodec,
 		appKeepers.keys[dyncommtypes.StoreKey],
@@ -504,6 +518,7 @@ func initParamsKeeper(
 	paramsKeeper.Subspace(treasurytypes.ModuleName)
 	paramsKeeper.Subspace(wasmtypes.ModuleName)
 	paramsKeeper.Subspace(dyncommtypes.ModuleName)
+	paramsKeeper.Subspace(taxtypes.ModuleName)
 
 	return paramsKeeper
 }

app/modules.go

@@ -25,6 +25,7 @@ import (
 	markettypes "github.com/classic-terra/core/v3/x/market/types"
 	"github.com/classic-terra/core/v3/x/oracle"
 	oracletypes "github.com/classic-terra/core/v3/x/oracle/types"
+	taxmodule "github.com/classic-terra/core/v3/x/tax/module"
 	"github.com/classic-terra/core/v3/x/treasury"
 	treasuryclient "github.com/classic-terra/core/v3/x/treasury/client"
 	treasurytypes "github.com/classic-terra/core/v3/x/treasury/types"
@@ -34,7 +35,6 @@ import (
 	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
 	"github.com/cosmos/cosmos-sdk/x/authz"
 	authzmodule "github.com/cosmos/cosmos-sdk/x/authz/module"
-	"github.com/cosmos/cosmos-sdk/x/bank"
 	banktypes "github.com/cosmos/cosmos-sdk/x/bank/types"
 	"github.com/cosmos/cosmos-sdk/x/capability"
 	capabilitytypes "github.com/cosmos/cosmos-sdk/x/capability/types"
@@ -78,6 +78,10 @@ import (
 	ibcexported "github.com/cosmos/ibc-go/v7/modules/core/exported"
 	ibctm "github.com/cosmos/ibc-go/v7/modules/light-clients/07-tendermint"
 
+	taxbank "github.com/classic-terra/core/v3/x/tax/modules/bank"
+	taxmarket "github.com/classic-terra/core/v3/x/tax/modules/market"
+	taxtypes "github.com/classic-terra/core/v3/x/tax/types"
+
 	// unnamed import of statik for swagger UI support
 	_ "github.com/classic-terra/core/v3/client/docs/statik"
 )
@@ -125,6 +129,7 @@ var (
 		dyncomm.AppModuleBasic{},
 		ibchooks.AppModuleBasic{},
 		consensus.AppModuleBasic{},
+		taxmodule.AppModuleBasic{},
 	)
 	// module account permissions
 	maccPerms = map[string][]string{
@@ -163,7 +168,7 @@ func appModules(
 			encodingConfig.TxConfig,
 		),
 		auth.NewAppModule(appCodec, app.AccountKeeper, nil, app.GetSubspace(authtypes.ModuleName)),
-		bank.NewAppModule(appCodec, app.BankKeeper, app.AccountKeeper, app.GetSubspace(banktypes.ModuleName)),
+		taxbank.NewAppModule(appCodec, app.BankKeeper, app.AccountKeeper, app.TreasuryKeeper, app.GetSubspace(banktypes.ModuleName), app.TaxKeeper),
 		capability.NewAppModule(appCodec, *app.CapabilityKeeper, false),
 		feegrantmodule.NewAppModule(appCodec, app.AccountKeeper, app.BankKeeper, app.FeeGrantKeeper, app.interfaceRegistry),
 		gov.NewAppModule(appCodec, &app.GovKeeper, app.AccountKeeper, app.BankKeeper, app.GetSubspace(govtypes.ModuleName)),
@@ -179,13 +184,14 @@ func appModules(
 		transfer.NewAppModule(app.TransferKeeper),
 		ibcfee.NewAppModule(app.IBCFeeKeeper),
 		ica.NewAppModule(&app.ICAControllerKeeper, &app.ICAHostKeeper),
-		market.NewAppModule(appCodec, app.MarketKeeper, app.AccountKeeper, app.BankKeeper, app.OracleKeeper),
+		taxmarket.NewAppModule(appCodec, app.MarketKeeper, app.AccountKeeper, app.TreasuryKeeper, app.BankKeeper, app.OracleKeeper, app.TaxKeeper),
 		oracle.NewAppModule(appCodec, app.OracleKeeper, app.AccountKeeper, app.BankKeeper),
 		treasury.NewAppModule(appCodec, app.TreasuryKeeper),
 		wasm.NewAppModule(appCodec, &app.WasmKeeper, app.StakingKeeper, app.AccountKeeper, app.BankKeeper, app.MsgServiceRouter(), app.GetSubspace(wasmtypes.ModuleName)),
 		dyncomm.NewAppModule(appCodec, app.DyncommKeeper, app.StakingKeeper),
 		ibchooks.NewAppModule(app.AccountKeeper),
 		consensus.NewAppModule(appCodec, app.ConsensusParamsKeeper),
+		taxmodule.NewAppModule(appCodec, app.TaxKeeper),
 		crisis.NewAppModule(app.CrisisKeeper, skipGenesisInvariants, app.GetSubspace(crisistypes.ModuleName)), // always be last to make sure that it checks for all invariants and not only part of them
 	}
 }
@@ -218,6 +224,7 @@ func simulationModules(
 		treasury.NewAppModule(appCodec, app.TreasuryKeeper),
 		wasm.NewAppModule(appCodec, &app.WasmKeeper, app.StakingKeeper, app.AccountKeeper, app.BankKeeper, app.MsgServiceRouter(), app.GetSubspace(wasmtypes.ModuleName)),
 		dyncomm.NewAppModule(appCodec, app.DyncommKeeper, app.StakingKeeper),
+		taxmodule.NewAppModule(appCodec, app.TaxKeeper),
 	}
 }
 
@@ -250,6 +257,7 @@ func orderBeginBlockers() []string {
 		markettypes.ModuleName,
 		wasmtypes.ModuleName,
 		dyncommtypes.ModuleName,
+		taxtypes.ModuleName,
 		// consensus module
 		consensusparamtypes.ModuleName,
 	}
@@ -284,6 +292,7 @@ func orderEndBlockers() []string {
 		markettypes.ModuleName,
 		wasmtypes.ModuleName,
 		dyncommtypes.ModuleName,
+		taxtypes.ModuleName,
 		// consensus module
 		consensusparamtypes.ModuleName,
 	}
@@ -318,6 +327,7 @@ func orderInitGenesis() []string {
 		treasurytypes.ModuleName,
 		wasmtypes.ModuleName,
 		dyncommtypes.ModuleName,
+		taxtypes.ModuleName,
 		// consensus module
 		consensusparamtypes.ModuleName,
 	}

app/testing/test_suite.go

@@ -9,9 +9,11 @@ import (
 	wasmtypes "github.com/CosmWasm/wasmd/x/wasm/types"
 	"github.com/classic-terra/core/v3/app"
 	appparams "github.com/classic-terra/core/v3/app/params"
+	core "github.com/classic-terra/core/v3/types"
 	dyncommtypes "github.com/classic-terra/core/v3/x/dyncomm/types"
 	markettypes "github.com/classic-terra/core/v3/x/market/types"
 	oracletypes "github.com/classic-terra/core/v3/x/oracle/types"
+	taxtypes "github.com/classic-terra/core/v3/x/tax/types"
 	treasurytypes "github.com/classic-terra/core/v3/x/treasury/types"
 	dbm "github.com/cometbft/cometbft-db"
 	abci "github.com/cometbft/cometbft/abci/types"
@@ -283,6 +285,11 @@ func genesisStateWithValSet(t *testing.T,
 	treasuryGensis := treasurytypes.DefaultGenesisState()
 	genesisState[treasurytypes.ModuleName] = app.AppCodec().MustMarshalJSON(treasuryGensis)
 
+	// update tax genesis state
+	taxGenesis := taxtypes.DefaultGenesisState()
+	taxGenesis.Params.GasPrices = sdk.NewDecCoins(sdk.NewDecCoin(core.MicroSDRDenom, sdk.ZeroInt())) // tests normally rely on zero gas price, so we are setting it here and fall back to the normal ctx.MinGasPrices
+	genesisState[taxtypes.ModuleName] = app.AppCodec().MustMarshalJSON(taxGenesis)
+
 	// update wasm genesis state
 	wasmGenesis := &wasmtypes.GenesisState{
 		Params: wasmtypes.DefaultParams(),

app/upgrades/v10/constants.go

@@ -0,0 +1,20 @@
+package v10
+
+import (
+	"github.com/classic-terra/core/v3/app/upgrades"
+	store "github.com/cosmos/cosmos-sdk/store/types"
+
+	tax2gastypes "github.com/classic-terra/core/v3/x/tax/types"
+)
+
+const UpgradeName = "v10"
+
+var Upgrade = upgrades.Upgrade{
+	UpgradeName:          UpgradeName,
+	CreateUpgradeHandler: CreateV10UpgradeHandler,
+	StoreUpgrades: store.StoreUpgrades{
+		Added: []string{
+			tax2gastypes.ModuleName,
+		},
+	},
+}

app/upgrades/v10/upgrades.go

@@ -0,0 +1,26 @@
+package v10
+
+import (
+	"github.com/classic-terra/core/v3/app/keepers"
+	"github.com/classic-terra/core/v3/app/upgrades"
+	taxtypes "github.com/classic-terra/core/v3/x/tax/types"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/types/module"
+	upgradetypes "github.com/cosmos/cosmos-sdk/x/upgrade/types"
+)
+
+func CreateV10UpgradeHandler(
+	mm *module.Manager,
+	cfg module.Configurator,
+	_ upgrades.BaseAppParamManager,
+	keepers *keepers.AppKeepers,
+) upgradetypes.UpgradeHandler {
+	return func(ctx sdk.Context, _ upgradetypes.Plan, fromVM module.VersionMap) (module.VersionMap, error) {
+		// set default oracle split
+		keepers.TreasuryKeeper.SetTaxRate(ctx, sdk.ZeroDec())
+
+		tax2gasParams := taxtypes.DefaultParams()
+		keepers.TaxKeeper.SetParams(ctx, tax2gasParams)
+		return mm.RunMigrations(ctx, cfg, fromVM)
+	}
+}

client/docs/swagger-ui/swagger.yaml

@@ -26570,6 +26570,45 @@ paths:
                       format: byte
       tags:
         - Query
+  /terra/tax/v1beta1/burn_tax_rate:
+    get:
+      summary: BurnTaxRate return the current tax rate
+      operationId: BurnTaxRate
+      responses:
+        '200':
+          description: A successful response.
+          schema:
+            type: object
+            properties:
+              tax_rate:
+                type: string
+            description: |-
+              QueryBurnTaxRateResponse is response type for the
+              Query/BurnTaxRate RPC method.
+        default:
+          description: An unexpected error response.
+          schema:
+            type: object
+            properties:
+              error:
+                type: string
+              code:
+                type: integer
+                format: int32
+              message:
+                type: string
+              details:
+                type: array
+                items:
+                  type: object
+                  properties:
+                    type_url:
+                      type: string
+                    value:
+                      type: string
+                      format: byte
+      tags:
+        - Query
   /terra/dyncomm/v1beta1/params:
     get:
       summary: Params queries all parameters.

contrib/updates/prepare_cosmovisor.sh

@@ -5,7 +5,7 @@
 
 # These fields should be fetched automatically in the future
 # Need to do more upgrade to see upgrade patterns
-OLD_VERSION=v3.1.3
+OLD_VERSION=v3.1.6
 # this command will retrieve the folder with the largest number in format v<number>
 SOFTWARE_UPGRADE_NAME=$(ls -d -- ./app/upgrades/v* | sort -Vr | head -n 1 | xargs basename)
 BUILDDIR=$1

custom/auth/ante/ante.go

@@ -17,6 +17,8 @@ import (
 	ibcante "github.com/cosmos/ibc-go/v7/modules/core/ante"
 	ibckeeper "github.com/cosmos/ibc-go/v7/modules/core/keeper"
 
+	taxkeeper "github.com/classic-terra/core/v3/x/tax/keeper"
+
 	wasmkeeper "github.com/CosmWasm/wasmd/x/wasm/keeper"
 	wasmtypes "github.com/CosmWasm/wasmd/x/wasm/types"
 )
@@ -40,6 +42,7 @@ type HandlerOptions struct {
 	TXCounterStoreKey      storetypes.StoreKey
 	DyncommKeeper          dyncommkeeper.Keeper
 	StakingKeeper          *stakingkeeper.Keeper
+	TaxKeeper              *taxkeeper.Keeper
 	Cdc                    codec.BinaryCodec
 }
 
@@ -75,6 +78,10 @@ func NewAnteHandler(options HandlerOptions) (sdk.AnteHandler, error) {
 		return nil, errorsmod.Wrap(sdkerrors.ErrLogic, "tx counter key is required for ante builder")
 	}
 
+	if options.TaxKeeper == nil {
+		return nil, errorsmod.Wrap(sdkerrors.ErrLogic, "tax handler is required for ante builder")
+	}
+
 	return sdk.ChainAnteDecorators(
 		ante.NewSetUpContextDecorator(), // outermost AnteDecorator. SetUpContext must be called first
 		wasmkeeper.NewLimitSimulationGasDecorator(options.WasmConfig.SimulationGasLimit),
@@ -88,7 +95,7 @@ func NewAnteHandler(options HandlerOptions) (sdk.AnteHandler, error) {
 		// MinInitialDepositDecorator prevents submitting governance proposal low initial deposit
 		NewMinInitialDepositDecorator(options.GovKeeper, options.TreasuryKeeper),
 		ante.NewConsumeGasForTxSizeDecorator(options.AccountKeeper),
-		NewFeeDecorator(options.AccountKeeper, options.BankKeeper, options.FeegrantKeeper, options.TreasuryKeeper, options.DistributionKeeper),
+		NewFeeDecorator(options.AccountKeeper, options.BankKeeper, options.FeegrantKeeper, options.TreasuryKeeper, options.DistributionKeeper, *options.TaxKeeper),
 		dyncommante.NewDyncommDecorator(options.Cdc, options.DyncommKeeper, options.StakingKeeper),
 
 		// Do not add any other decorators below this point unless explicitly explain.

custom/auth/ante/ante_test.go

@@ -22,6 +22,7 @@ import (
 	distributiontypes "github.com/cosmos/cosmos-sdk/x/distribution/types"
 
 	terraapp "github.com/classic-terra/core/v3/app"
+	taxtypes "github.com/classic-terra/core/v3/x/tax/types"
 	treasurytypes "github.com/classic-terra/core/v3/x/treasury/types"
 
 	wasmkeeper "github.com/CosmWasm/wasmd/x/wasm/keeper"
@@ -53,6 +54,9 @@ func createTestApp(isCheckTx bool, tempDir string) (*terraapp.TerraApp, sdk.Cont
 	app.DistrKeeper.SetParams(ctx, distributiontypes.DefaultParams())
 	app.DistrKeeper.SetFeePool(ctx, distributiontypes.InitialFeePool())
 
+	taxParams := taxtypes.DefaultParams()
+	taxParams.GasPrices = sdk.NewDecCoins() // tests normally rely on zero gas price, so we are setting it here and fall back to the normal ctx.MinGasPrices
+	app.TaxKeeper.SetParams(ctx, taxParams)
 	return app, ctx
 }
 

custom/auth/ante/expected_keeper.go

@@ -44,3 +44,7 @@ type DistrKeeper interface {
 type GovKeeper interface {
 	GetDepositParams(ctx sdk.Context) govv1.DepositParams
 }
+
+type TaxKeeper interface {
+	GetBurnTaxRate(ctx sdk.Context) sdk.Dec
+}