feat: ADR-008: Fees module (#796)

## Description

Closes: #XXXX.

This PR implements the `x/fees` module that allows governance to set minimum fees on messages.

Depends-On: #816
Depends-On: #817

---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/desmos-labs/desmos/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://docs.cosmos.network/v0.44/building-modules/intro.html)
- [ ] included the necessary unit and integration [tests](https://github.com/desmos-labs/desmos/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [x] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [x] confirmed all author checklist items have been addressed
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [x] reviewed tests and test coverage
- [ ] manually tested (if applicable)

.changeset/config.yaml

@@ -58,6 +58,8 @@ types:
     hide: true
 
 modules:
+  - id: x/fees
+    description: Fees
   - id: x/profiles
     description: Profiles
   - id: x/subspaces

.changeset/entries/e0e50784a9447e03a4cab7f42c4020754fdb7fc2fabae2a8ce80f15be54561e2.yaml

@@ -0,0 +1,6 @@
+type: feat
+module: x/fees
+pull_request: 796
+description: Added the new `x/fees` module
+backward_compatible: true
+date: 2022-04-08T10:16:28.516096837Z

.github/labeler.yml

@@ -1,7 +1,9 @@
+"x/fees":
+  - x/fees/**/*
 "x/profiles":
   - x/profiles/**/*
-"x/posts":
-  - x/posts/**/*
+"x/relationships":
+  - x/relationships/**/*
 "x/subspaces":
   - x/subspaces/**/*
 "x/CLI":

app/ante.go

@@ -7,6 +7,8 @@ import (
 	channelkeeper "github.com/cosmos/ibc-go/v2/modules/core/04-channel/keeper"
 	ibcante "github.com/cosmos/ibc-go/v2/modules/core/ante"
 
+	feeskeeper "github.com/desmos-labs/desmos/v3/x/fees/keeper"
+
 	wasmkeeper "github.com/CosmWasm/wasmd/x/wasm/keeper"
 	wasmTypes "github.com/CosmWasm/wasmd/x/wasm/types"
 )
@@ -17,6 +19,7 @@ type HandlerOptions struct {
 	ante.HandlerOptions
 
 	IBCChannelkeeper  channelkeeper.Keeper
+	FeesKeeper        feeskeeper.Keeper
 	TxCounterStoreKey sdk.StoreKey
 	WasmConfig        wasmTypes.WasmConfig
 }
@@ -37,12 +40,13 @@ func NewAnteHandler(options HandlerOptions) (sdk.AnteHandler, error) {
 		sigGasConsumer = ante.DefaultSigVerificationGasConsumer
 	}
 
-	anteDecorators := []sdk.AnteDecorator{
+	return sdk.ChainAnteDecorators(
 		ante.NewSetUpContextDecorator(),
 		wasmkeeper.NewLimitSimulationGasDecorator(options.WasmConfig.SimulationGasLimit),
 		wasmkeeper.NewCountTXDecorator(options.TxCounterStoreKey),
 		ante.NewRejectExtensionOptionsDecorator(),
 		ante.NewMempoolFeeDecorator(),
+		feeskeeper.NewMinFeeDecorator(options.FeesKeeper),
 		ante.NewValidateBasicDecorator(),
 		ante.NewTxTimeoutHeightDecorator(),
 		ante.NewValidateMemoDecorator(options.AccountKeeper),
@@ -55,7 +59,5 @@ func NewAnteHandler(options HandlerOptions) (sdk.AnteHandler, error) {
 		ante.NewSigVerificationDecorator(options.AccountKeeper, options.SignModeHandler),
 		ante.NewIncrementSequenceDecorator(options.AccountKeeper),
 		ibcante.NewAnteDecorator(options.IBCChannelkeeper),
-	}
-
-	return sdk.ChainAnteDecorators(anteDecorators...), nil
+	), nil
 }

app/app.go

@@ -13,10 +13,12 @@ import (
 	"github.com/desmos-labs/desmos/v3/x/relationships"
 	relationshipstypes "github.com/desmos-labs/desmos/v3/x/relationships/types"
 
-	"github.com/desmos-labs/desmos/v3/x/subspaces"
-
 	"github.com/cosmos/cosmos-sdk/version"
 
+	"github.com/desmos-labs/desmos/v3/x/fees"
+	feeskeeper "github.com/desmos-labs/desmos/v3/x/fees/keeper"
+	feestypes "github.com/desmos-labs/desmos/v3/x/fees/types"
+
 	"github.com/cosmos/cosmos-sdk/x/auth/vesting"
 	vestingtypes "github.com/cosmos/cosmos-sdk/x/auth/vesting/types"
 	"github.com/cosmos/cosmos-sdk/x/authz"
@@ -93,6 +95,8 @@ import (
 	profileskeeper "github.com/desmos-labs/desmos/v3/x/profiles/keeper"
 	profilestypes "github.com/desmos-labs/desmos/v3/x/profiles/types"
 	relationshipskeeper "github.com/desmos-labs/desmos/v3/x/relationships/keeper"
+
+	"github.com/desmos-labs/desmos/v3/x/subspaces"
 	subspaceskeeper "github.com/desmos-labs/desmos/v3/x/subspaces/keeper"
 	subspacestypes "github.com/desmos-labs/desmos/v3/x/subspaces/types"
 
@@ -226,6 +230,7 @@ var (
 		profiles.AppModuleBasic{},
 		relationships.AppModuleBasic{},
 		subspaces.AppModuleBasic{},
+		fees.AppModuleBasic{},
 		supply.AppModuleBasic{},
 	)
 
@@ -286,6 +291,7 @@ type DesmosApp struct {
 	ScopedWasmKeeper        capabilitykeeper.ScopedKeeper
 
 	// Custom modules
+	FeesKeeper          feeskeeper.Keeper
 	SubspacesKeeper     subspaceskeeper.Keeper
 	ProfileKeeper       profileskeeper.Keeper
 	RelationshipsKeeper relationshipskeeper.Keeper
@@ -336,7 +342,8 @@ func NewDesmosApp(
 		authzkeeper.StoreKey, wasm.StoreKey,
 
 		// Custom modules
-		profilestypes.StoreKey, relationshipstypes.StoreKey, subspacestypes.StoreKey, supplytypes.StoreKey,
+		profilestypes.StoreKey, relationshipstypes.StoreKey, subspacestypes.StoreKey,
+		feestypes.StoreKey, supplytypes.StoreKey,
 	)
 	tkeys := sdk.NewTransientStoreKeys(paramstypes.TStoreKey)
 	memKeys := sdk.NewMemoryStoreKeys(capabilitytypes.MemStoreKey)
@@ -426,6 +433,9 @@ func NewDesmosApp(
 	)
 	transferModule := ibctransfer.NewAppModule(app.TransferKeeper)
 
+	// Create fees keeper
+	app.FeesKeeper = feeskeeper.NewKeeper(app.appCodec, app.GetSubspace(feestypes.ModuleName))
+
 	// Create subspaces keeper and module
 	subspacesKeeper := subspaceskeeper.NewKeeper(app.appCodec, keys[subspacestypes.StoreKey])
 
@@ -454,6 +464,7 @@ func NewDesmosApp(
 		app.ProfileKeeper,
 		app.AccountKeeper,
 		app.BankKeeper,
+		app.FeesKeeper,
 	)
 
 	// Register the subspaces hooks
@@ -560,9 +571,14 @@ func NewDesmosApp(
 		wasm.NewAppModule(appCodec, &app.WasmKeeper, app.StakingKeeper),
 
 		// Custom modules
-		subspaces.NewAppModule(appCodec, app.SubspacesKeeper, app.AccountKeeper, app.BankKeeper),
+		fees.NewAppModule(app.appCodec, app.FeesKeeper),
+		subspaces.NewAppModule(appCodec, app.SubspacesKeeper, app.AccountKeeper, app.BankKeeper, app.FeesKeeper),
 		profilesModule,
-		relationships.NewAppModule(appCodec, app.RelationshipsKeeper, app.SubspacesKeeper, profilesv4.NewKeeper(keys[profilestypes.StoreKey], appCodec), app.AccountKeeper, app.BankKeeper),
+		relationships.NewAppModule(
+			appCodec, app.RelationshipsKeeper, app.SubspacesKeeper,
+			profilesv4.NewKeeper(keys[profilestypes.StoreKey], appCodec), app.AccountKeeper,
+			app.BankKeeper, app.FeesKeeper,
+		),
 		supply.NewAppModule(appCodec, legacyAmino, app.SupplyKeeper),
 	)
 
@@ -592,6 +608,7 @@ func NewDesmosApp(
 		ibctransfertypes.ModuleName,
 		wasm.ModuleName,
 
+		feestypes.ModuleName,
 		subspacestypes.ModuleName,
 		relationshipstypes.ModuleName,
 		profilestypes.ModuleName,
@@ -618,6 +635,7 @@ func NewDesmosApp(
 		ibctransfertypes.ModuleName,
 		wasm.ModuleName,
 
+		feestypes.ModuleName,
 		subspacestypes.ModuleName,
 		relationshipstypes.ModuleName,
 		profilestypes.ModuleName,
@@ -651,6 +669,7 @@ func NewDesmosApp(
 		wasm.ModuleName,
 
 		// Custom modules
+		feestypes.ModuleName,
 		subspacestypes.ModuleName,
 		profilestypes.ModuleName,
 		relationshipstypes.ModuleName,
@@ -683,6 +702,7 @@ func NewDesmosApp(
 		wasm.ModuleName,
 
 		// Custom modules
+		feestypes.ModuleName,
 		subspacestypes.ModuleName,
 		relationshipstypes.ModuleName,
 		profilestypes.ModuleName,
@@ -721,10 +741,15 @@ func NewDesmosApp(
 		wasm.NewAppModule(appCodec, &app.WasmKeeper, app.StakingKeeper),
 
 		// Custom modules
+		fees.NewAppModule(appCodec, app.FeesKeeper),
 		supply.NewAppModule(appCodec, legacyAmino, app.SupplyKeeper),
-		subspaces.NewAppModule(appCodec, app.SubspacesKeeper, app.AccountKeeper, app.BankKeeper),
+		subspaces.NewAppModule(appCodec, app.SubspacesKeeper, app.AccountKeeper, app.BankKeeper, app.FeesKeeper),
 		profilesModule,
-		relationships.NewAppModule(appCodec, app.RelationshipsKeeper, app.SubspacesKeeper, profilesv4.NewKeeper(keys[profilestypes.StoreKey], appCodec), app.AccountKeeper, app.BankKeeper),
+		relationships.NewAppModule(
+			appCodec, app.RelationshipsKeeper, app.SubspacesKeeper,
+			profilesv4.NewKeeper(keys[profilestypes.StoreKey], appCodec), app.AccountKeeper,
+			app.BankKeeper, app.FeesKeeper,
+		),
 	)
 
 	app.sm.RegisterStoreDecoders()
@@ -747,6 +772,7 @@ func NewDesmosApp(
 				SigGasConsumer:  ante.DefaultSigVerificationGasConsumer,
 			},
 			IBCChannelkeeper:  app.IBCKeeper.ChannelKeeper,
+			FeesKeeper:        app.FeesKeeper,
 			TxCounterStoreKey: keys[wasm.StoreKey],
 			WasmConfig:        wasmConfig,
 		},
@@ -986,6 +1012,8 @@ func initParamsKeeper(appCodec codec.BinaryCodec, legacyAmino *codec.LegacyAmino
 	paramsKeeper.Subspace(ibchost.ModuleName)
 	paramsKeeper.Subspace(wasm.ModuleName)
 
+	paramsKeeper.Subspace(feestypes.ModuleName)
+	paramsKeeper.Subspace(subspacestypes.ModuleName)
 	paramsKeeper.Subspace(profilestypes.ModuleName)
 
 	return paramsKeeper

app/sim_test.go

@@ -8,6 +8,8 @@ import (
 	"path/filepath"
 	"testing"
 
+	feestypes "github.com/desmos-labs/desmos/v3/x/fees/types"
+
 	relationshipstypes "github.com/desmos-labs/desmos/v3/x/relationships/types"
 
 	authzkeeper "github.com/cosmos/cosmos-sdk/x/authz/keeper"
@@ -229,6 +231,7 @@ func TestAppImportExport(t *testing.T) {
 		{app.keys[ibchost.StoreKey], newApp.keys[ibchost.StoreKey], [][]byte{}},
 		{app.keys[ibctransfertypes.StoreKey], newApp.keys[ibctransfertypes.StoreKey], [][]byte{}},
 
+		{app.keys[feestypes.StoreKey], newApp.keys[feestypes.StoreKey], [][]byte{}},
 		{app.keys[subspacestypes.StoreKey], newApp.keys[subspacestypes.StoreKey], [][]byte{}},
 		{app.keys[profilestypes.StoreKey], newApp.keys[profilestypes.StoreKey], [][]byte{}},
 		{app.keys[relationshipstypes.StoreKey], newApp.keys[relationshipstypes.StoreKey], [][]byte{}},

proto/desmos/fees/v1/genesis.proto

@@ -0,0 +1,14 @@
+syntax = "proto3";
+package desmos.fees.v1;
+
+import "gogoproto/gogo.proto";
+import "desmos/fees/v1/params.proto";
+
+option go_package = "github.com/desmos-labs/desmos/v3/x/fees/types";
+
+// GenesisState contains the data of the genesis state for the fees module
+message GenesisState {
+  option (gogoproto.goproto_getters) = false;
+
+  desmos.fees.v1.Params params = 1 [ (gogoproto.nullable) = false ];
+}

proto/desmos/fees/v1/min_fee.proto

@@ -0,0 +1,19 @@
+syntax = "proto3";
+package desmos.fees.v1;
+
+import "gogoproto/gogo.proto";
+import "cosmos/base/v1beta1/coin.proto";
+
+option go_package = "github.com/desmos-labs/desmos/v3/x/fees/types";
+
+// MinFee contains the minimum amount of coins that should be paid as a fee for
+// each message of the specific type sent
+message MinFee {
+  string message_type = 1 [ (gogoproto.moretags) = "yaml:\"message_type\"" ];
+
+  repeated cosmos.base.v1beta1.Coin amount = 2 [
+    (gogoproto.nullable) = false,
+    (gogoproto.castrepeated) = "github.com/cosmos/cosmos-sdk/types.Coins",
+    (gogoproto.moretags) = "yaml:\"amount\""
+  ];
+}

proto/desmos/fees/v1/params.proto

@@ -0,0 +1,15 @@
+syntax = "proto3";
+package desmos.fees.v1;
+
+import "gogoproto/gogo.proto";
+import "desmos/fees/v1/min_fee.proto";
+
+option go_package = "github.com/desmos-labs/desmos/v3/x/fees/types";
+
+// Params contains the parameters for the fees module
+message Params {
+  repeated desmos.fees.v1.MinFee min_fees = 1 [
+    (gogoproto.nullable) = false,
+    (gogoproto.moretags) = "yaml:\"min_fees\""
+  ];
+}

proto/desmos/fees/v1/query.proto

@@ -0,0 +1,26 @@
+syntax = "proto3";
+package desmos.fees.v1;
+
+import "gogoproto/gogo.proto";
+import "google/api/annotations.proto";
+import "desmos/fees/v1/params.proto";
+
+option go_package = "github.com/desmos-labs/desmos/v3/x/fees/types";
+
+// Query defines the gRPC querier service.
+service Query {
+  // Params queries the fees module params
+  rpc Params(QueryParamsRequest) returns (QueryParamsResponse) {
+    option (google.api.http).get = "/desmos/fees/v1/fees/params";
+  }
+}
+
+// ___________________________________________________________________________________________________________________
+
+// QueryParamsRequest is the request type for the Query/Params RPC method.
+message QueryParamsRequest {}
+
+// QueryParamsResponse is the response type for the Query/Params RPC
+message QueryParamsResponse {
+  desmos.fees.v1.Params params = 1 [ (gogoproto.nullable) = false ];
+}

testutil/simtesting/utils.go

@@ -3,6 +3,8 @@ package simtesting
 import (
 	"math/rand"
 
+	feeskeeper "github.com/desmos-labs/desmos/v3/x/fees/keeper"
+
 	"github.com/cosmos/cosmos-sdk/baseapp"
 
 	cryptotypes "github.com/cosmos/cosmos-sdk/crypto/types"
@@ -16,18 +18,22 @@ import (
 
 // SendMsg sends a transaction with the specified message.
 func SendMsg(
-	r *rand.Rand, app *baseapp.BaseApp, ak authkeeper.AccountKeeper, bk bankkeeper.Keeper,
+	r *rand.Rand, app *baseapp.BaseApp, ak authkeeper.AccountKeeper, bk bankkeeper.Keeper, fk feeskeeper.Keeper,
 	msg sdk.Msg, ctx sdk.Context, chainID string, gasValue uint64, privkeys []cryptotypes.PrivKey,
 ) error {
 	addr := msg.GetSigners()[0]
 	account := ak.GetAccount(ctx, addr)
 	coins := bk.SpendableCoins(ctx, account.GetAddress())
 
-	fees, err := simtypes.RandomFees(r, ctx, coins)
+	fees, sendTx, err := computeFees(r, ctx, fk, msg, coins)
 	if err != nil {
 		return err
 	}
 
+	if !sendTx {
+		return nil
+	}
+
 	txGen := simappparams.MakeTestEncodingConfig().TxConfig
 	tx, err := helpers.GenTx(
 		txGen,
@@ -50,3 +56,21 @@ func SendMsg(
 
 	return nil
 }
+
+// computeFees computes the fees that should be used to send a transaction with the given message,
+// considering the max spendable amount provided and the min fees set inside the fees module
+func computeFees(
+	r *rand.Rand, ctx sdk.Context, fk feeskeeper.Keeper, msg sdk.Msg, max sdk.Coins,
+) (fees sdk.Coins, sendTx bool, err error) {
+	minFees := fk.GetParams(ctx).MinFees
+	for _, minFee := range minFees {
+		if sdk.MsgTypeURL(msg) == minFee.MessageType {
+			fees = minFee.Amount
+			sendTx = fees.IsAllLT(max)
+			return
+		}
+	}
+
+	fees, err = simtypes.RandomFees(r, ctx, max)
+	return
+}