feat: denom parameter (#29)

* proto

* add param

* add get

* test

* format

proto/feemarket/feemarket/v1/genesis.proto

@@ -45,11 +45,11 @@ message State {
   // Index is the index of the current block in the block utilization window.
   uint64 index = 4;
 
-  // MaxBlockUtilization is the maximum utilization of a given block. This is denominated
-  // in the number of gas units consumed per block.
+  // MaxBlockUtilization is the maximum utilization of a given block. This is
+  // denominated in the number of gas units consumed per block.
   uint64 max_block_utilization = 5;
 
-  // TargetBlockUtilization is the target utilization of a given block. This is denominated
-  // in the number of gas units consumed per block.
+  // TargetBlockUtilization is the target utilization of a given block. This is
+  // denominated in the number of gas units consumed per block.
   uint64 target_block_utilization = 6;
 }

proto/feemarket/feemarket/v1/params.proto

@@ -77,7 +77,10 @@ message Params {
   // over a moving window of blocks.
   uint64 window = 10;
 
+  // FeeDenom is the denom that will be used for all fee payments.
+  string fee_denom = 11;
+
   // Enabled is a boolean that determines whether the EIP1559 fee market is
   // enabled.
-  bool enabled = 11;
+  bool enabled = 12;
 }

x/feemarket/keeper/feemarket.go

@@ -71,3 +71,21 @@ func (k *Keeper) GetLearningRate(ctx sdk.Context) (math.LegacyDec, error) {
 
 	return state.LearningRate, nil
 }
+
+// GetMinGasPrices returns the mininum gas prices as sdk.Coins from the fee market state.
+func (k *Keeper) GetMinGasPrices(ctx sdk.Context) (sdk.Coins, error) {
+	baseFee, err := k.GetBaseFee(ctx)
+	if err != nil {
+		return sdk.NewCoins(), err
+	}
+
+	params, err := k.GetParams(ctx)
+	if err != nil {
+		return sdk.NewCoins(), err
+	}
+
+	fee := sdk.NewCoin(params.FeeDenom, baseFee)
+	minGasPrices := sdk.NewCoins(fee)
+
+	return minGasPrices, nil
+}

x/feemarket/keeper/feemarket_test.go

@@ -1,6 +1,8 @@
 package keeper_test
 
 import (
+	sdk "github.com/cosmos/cosmos-sdk/types"
+
 	"github.com/skip-mev/feemarket/x/feemarket/types"
 )
 
@@ -47,3 +49,27 @@ func (s *KeeperTestSuite) TestGetLearningRate() {
 		s.Require().Equal(lr, gs.State.LearningRate)
 	})
 }
+
+func (s *KeeperTestSuite) TestGetMinGasPrices() {
+	s.Run("can retrieve min gas prices with default eip-1559", func() {
+		gs := types.DefaultGenesisState()
+		s.feemarketKeeper.InitGenesis(s.ctx, *gs)
+
+		expected := sdk.NewCoins(sdk.NewCoin(sdk.DefaultBondDenom, gs.State.BaseFee))
+
+		mgp, err := s.feemarketKeeper.GetMinGasPrices(s.ctx)
+		s.Require().NoError(err)
+		s.Require().Equal(expected, mgp)
+	})
+
+	s.Run("can retrieve min gas prices with aimd eip-1559", func() {
+		gs := types.DefaultAIMDGenesisState()
+		s.feemarketKeeper.InitGenesis(s.ctx, *gs)
+
+		expected := sdk.NewCoins(sdk.NewCoin(sdk.DefaultBondDenom, gs.State.BaseFee))
+
+		mgp, err := s.feemarketKeeper.GetMinGasPrices(s.ctx)
+		s.Require().NoError(err)
+		s.Require().Equal(expected, mgp)
+	})
+}

x/feemarket/types/eip1559.go

@@ -1,6 +1,9 @@
 package types
 
-import "cosmossdk.io/math"
+import (
+	"cosmossdk.io/math"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+)
 
 // Note: We use the same default values as Ethereum for the EIP-1559
 // fee market implementation. These parameters do not implement the
@@ -13,16 +16,16 @@ var (
 	DefaultWindow uint64 = 1
 
 	// DefaultAlpha is not used in the base EIP-1559 implementation.
-	DefaultAlpha math.LegacyDec = math.LegacyMustNewDecFromStr("0.0")
+	DefaultAlpha = math.LegacyMustNewDecFromStr("0.0")
 
 	// DefaultBeta is not used in the base EIP-1559 implementation.
-	DefaultBeta math.LegacyDec = math.LegacyMustNewDecFromStr("1.0")
+	DefaultBeta = math.LegacyMustNewDecFromStr("1.0")
 
 	// DefaultTheta is not used in the base EIP-1559 implementation.
-	DefaultTheta math.LegacyDec = math.LegacyMustNewDecFromStr("0.0")
+	DefaultTheta = math.LegacyMustNewDecFromStr("0.0")
 
 	// DefaultDelta is not used in the base EIP-1559 implementation.
-	DefaultDelta math.LegacyDec = math.LegacyMustNewDecFromStr("0.0")
+	DefaultDelta = math.LegacyMustNewDecFromStr("0.0")
 
 	// DefaultTargetBlockSize is the default target block utilization. This is the default
 	// on Ethereum. This denominated in units of gas consumed in a block.
@@ -35,13 +38,16 @@ var (
 	// DefaultMinBaseFee is the default minimum base fee. This is the default
 	// on Ethereum. Note that Ethereum is denominated in 1e18 wei. Cosmos chains will
 	// likely want to change this to 1e6.
-	DefaultMinBaseFee math.Int = math.NewInt(1_000_000_000)
+	DefaultMinBaseFee = math.NewInt(1_000_000_000)
 
 	// DefaultMinLearningRate is not used in the base EIP-1559 implementation.
-	DefaultMinLearningRate math.LegacyDec = math.LegacyMustNewDecFromStr("0.125")
+	DefaultMinLearningRate = math.LegacyMustNewDecFromStr("0.125")
 
 	// DefaultMaxLearningRate is not used in the base EIP-1559 implementation.
-	DefaultMaxLearningRate math.LegacyDec = math.LegacyMustNewDecFromStr("0.125")
+	DefaultMaxLearningRate = math.LegacyMustNewDecFromStr("0.125")
+
+	// DefaultFeeDenom is the Cosmos SDK default bond denom.
+	DefaultFeeDenom = sdk.DefaultBondDenom
 )
 
 // DefaultParams returns a default set of parameters that implements
@@ -59,6 +65,7 @@ func DefaultParams() Params {
 		DefaultMinBaseFee,
 		DefaultMinLearningRate,
 		DefaultMaxLearningRate,
+		DefaultFeeDenom,
 		true,
 	)
 }

x/feemarket/types/eip1559_aimd.go

@@ -14,24 +14,24 @@ var (
 	// DefaultAIMDAlpha is the default alpha value for the learning
 	// rate calculation. This value determines how much we want to additively
 	// increase the learning rate when the target block size is exceeded.
-	DefaultAIMDAlpha math.LegacyDec = math.LegacyMustNewDecFromStr("0.025")
+	DefaultAIMDAlpha = math.LegacyMustNewDecFromStr("0.025")
 
 	// DefaultAIMDBeta is the default beta value for the learning rate
 	// calculation. This value determines how much we want to multiplicatively
 	// decrease the learning rate when the target utilization is not met.
-	DefaultAIMDBeta math.LegacyDec = math.LegacyMustNewDecFromStr("0.95")
+	DefaultAIMDBeta = math.LegacyMustNewDecFromStr("0.95")
 
 	// DefaultAIMDTheta is the default threshold for determining whether
 	// to increase or decrease the learning rate. In this case, we increase
 	// the learning rate if the block utilization within the window is greater
 	// than 0.75 or less than 0.25. Otherwise, we multiplicatively decrease
 	// the learning rate.
-	DefaultAIMDTheta math.LegacyDec = math.LegacyMustNewDecFromStr("0.25")
+	DefaultAIMDTheta = math.LegacyMustNewDecFromStr("0.25")
 
 	// DefaultAIMDDelta is the default delta value for how much we additively
 	// increase or decrease the base fee when the net block utilization within
 	// the window is not equal to the target utilization.
-	DefaultAIMDDelta math.LegacyDec = math.LegacyMustNewDecFromStr("0.0")
+	DefaultAIMDDelta = math.LegacyMustNewDecFromStr("0.0")
 
 	// DefaultAIMDTargetBlockSize is the default target block utilization. This
 	// is the default on Ethereum. This denominated in units of gas consumed in
@@ -46,13 +46,16 @@ var (
 	// DefaultAIMDMinBaseFee is the default minimum base fee. This is the
 	// default on Ethereum. Note that ethereum is denominated in 1e18 wei.
 	// Cosmos chains will likely want to change this to 1e6.
-	DefaultAIMDMinBaseFee math.Int = math.NewInt(1_000_000_000)
+	DefaultAIMDMinBaseFee = math.NewInt(1_000_000_000)
 
 	// DefaultAIMDMinLearningRate is the default minimum learning rate.
-	DefaultAIMDMinLearningRate math.LegacyDec = math.LegacyMustNewDecFromStr("0.01")
+	DefaultAIMDMinLearningRate = math.LegacyMustNewDecFromStr("0.01")
 
 	// DefaultAIMDMaxLearningRate is the default maximum learning rate.
-	DefaultAIMDMaxLearningRate math.LegacyDec = math.LegacyMustNewDecFromStr("0.50")
+	DefaultAIMDMaxLearningRate = math.LegacyMustNewDecFromStr("0.50")
+
+	// DefaultAIMDFeeDenom is the Cosmos SDK default bond denom.
+	DefaultAIMDFeeDenom = DefaultFeeDenom
 )
 
 // DefaultAIMDParams returns a default set of parameters that implements
@@ -71,6 +74,7 @@ func DefaultAIMDParams() Params {
 		DefaultAIMDMinBaseFee,
 		DefaultAIMDMinLearningRate,
 		DefaultAIMDMaxLearningRate,
+		DefaultAIMDFeeDenom,
 		true,
 	)
 }

x/feemarket/types/params.go

@@ -19,6 +19,7 @@ func NewParams(
 	minBaseFee math.Int,
 	minLearingRate math.LegacyDec,
 	maxLearningRate math.LegacyDec,
+	feeDenom string,
 	enabled bool,
 ) Params {
 	return Params{
@@ -32,6 +33,7 @@ func NewParams(
 		TargetBlockUtilization: targetBlockSize,
 		MaxBlockUtilization:    maxBlockSize,
 		Window:                 window,
+		FeeDenom:               feeDenom,
 		Enabled:                enabled,
 	}
 }
@@ -86,5 +88,9 @@ func (p *Params) ValidateBasic() error {
 		return fmt.Errorf("min learning rate cannot be greater than max learning rate")
 	}
 
+	if p.FeeDenom == "" {
+		return fmt.Errorf("fee denom must be set")
+	}
+
 	return nil
 }