feat: feegrant module

CHANGELOG.md

@@ -7,6 +7,7 @@
 * (x/gov) [\#368](https://github.com/line/lbm-sdk/pull/368) Governance Split Votes, use `MsgWeightedVote` to send a split vote. Sending a regular `MsgVote` will convert the underlying vote option into a weighted vote with weight 1.
 * (x/upgrade) [\#377] (https://github.com/line/lbm-sdk/pull/377) To smoothen the update to the latest stable release, the SDK includes vesion map for managing migrations between SDK versions.
 * (x/wasm) [\#358] (https://github.com/line/lbm-sdk/pull/358) change wasm metrics method to using prometheus directly
+* (x/feegrant) [\#380] (https://github.com/line/lbm-sdk/pull/380) Feegrant module
 
 ### Improvements
 * (slashing) [\#347](https://github.com/line/lbm-sdk/pull/347) Introduce VoterSetCounter

baseapp/iostats_nop.go

@@ -5,5 +5,4 @@ package baseapp
 import "github.com/line/ostracon/libs/log"
 
 func logIoStats(logger log.Logger) {
-	return
 }

client/cmd.go

@@ -221,6 +221,18 @@ func readTxCommandFlags(clientCtx Context, flagSet *pflag.FlagSet) (Context, err
 		clientCtx = clientCtx.WithSignModeStr(signModeStr)
 	}
 
+	if clientCtx.FeeGranter == "" || flagSet.Changed(flags.FlagFeeAccount) {
+		granter, _ := flagSet.GetString(flags.FlagFeeAccount)
+
+		if granter != "" {
+			err := sdk.ValidateAccAddress(granter)
+			if err != nil {
+				return clientCtx, err
+			}
+			clientCtx = clientCtx.WithFeeGranterAddress(sdk.AccAddress(granter))
+		}
+	}
+
 	if clientCtx.From == "" || flagSet.Changed(flags.FlagFrom) {
 		from, _ := flagSet.GetString(flags.FlagFrom)
 		fromAddr, fromName, keyType, err := GetFromFields(clientCtx.Keyring, from, clientCtx.GenerateOnly)

client/context.go

@@ -44,6 +44,7 @@ type Context struct {
 	TxConfig          TxConfig
 	AccountRetriever  AccountRetriever
 	NodeURI           string
+	FeeGranter        sdk.AccAddress
 
 	// TODO: Deprecated (remove).
 	LegacyAmino *codec.LegacyAmino
@@ -86,6 +87,13 @@ func (ctx Context) WithFrom(from string) Context {
 	return ctx
 }
 
+// WithFeeGranterAddress returns a copy of the context with an updated fee granter account
+// address.
+func (ctx Context) WithFeeGranterAddress(addr sdk.AccAddress) Context {
+	ctx.FeeGranter = addr
+	return ctx
+}
+
 // WithOutputFormat returns a copy of the context with an updated OutputFormat field.
 func (ctx Context) WithOutputFormat(format string) Context {
 	ctx.OutputFormat = format

client/flags/flags.go

@@ -72,6 +72,7 @@ const (
 	FlagTimeoutHeight    = "timeout-height"
 	FlagKeyAlgorithm     = "algo"
 	FlagPrivKeyType      = "priv_key_type"
+	FlagFeeAccount       = "fee-account"
 
 	// Tendermint logging flags
 	FlagLogLevel       = "log_level"
@@ -117,6 +118,7 @@ func AddTxFlagsToCmd(cmd *cobra.Command) {
 	cmd.Flags().Uint64(FlagTimeoutHeight, 0, "Set a block timeout height to prevent the tx from being committed past a certain height")
 	cmd.Flags().String(FlagPrivKeyType, DefaultPrivKeyType, "specify validator's private key type (ed25519|composite). \n"+
 		"set this to priv_key.type in priv_validator_key.json; default `ed25519`")
+	cmd.Flags().String(FlagFeeAccount, "", "Fee account pays fees for the transaction instead of deducting from the signer")
 
 	// --gas can accept integers and "auto"
 	cmd.Flags().String(FlagGas, "", fmt.Sprintf("gas limit to set per-transaction; set to %q to calculate sufficient gas automatically (default %d)", GasFlagAuto, DefaultGasLimit))

client/query.go

@@ -57,6 +57,11 @@ func (ctx Context) GetFromAddress() sdk.AccAddress {
 	return ctx.FromAddress
 }
 
+// GetFeeGranterAddress returns the fee granter address from the context
+func (ctx Context) GetFeeGranterAddress() sdk.AccAddress {
+	return ctx.FeeGranter
+}
+
 // GetFromName returns the key name for the current context.
 func (ctx Context) GetFromName() string {
 	return ctx.FromName

client/tx/tx.go

@@ -117,6 +117,7 @@ func BroadcastTx(clientCtx client.Context, txf Factory, msgs ...sdk.Msg) error {
 		}
 	}
 
+	tx.SetFeeGranter(clientCtx.GetFeeGranterAddress())
 	err = Sign(txf, clientCtx.GetFromName(), tx, true)
 	if err != nil {
 		return err

client/tx_config.go

@@ -43,5 +43,6 @@ type (
 		SetFeeAmount(amount sdk.Coins)
 		SetGasLimit(limit uint64)
 		SetTimeoutHeight(height uint64)
+		SetFeeGranter(feeGranter sdk.AccAddress)
 	}
 )