feat: fee market module (#491)

* feat: fee market module * update proto * queriers: CLI + gRPC * gov params * genesis * enable height * fixes * fix app
2021-08-26 10:08:11 +00:00
parent 4b11ac66c4
commit f469db94ef
34 changed files with 3544 additions and 647 deletions
@@ -0,0 +1,79 @@
+package keeper
+
+import (
+	"math/big"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/math"
+)
+
+// CalculateBaseFee calculates the base fee for the current block. This is only calculated once per
+// block during EndBlock. If the NoBaseFee parameter is enabled, this function returns nil.
+// NOTE: This code is inspired from the go-ethereum EIP1559 implementation and adapted to Cosmos SDK-based
+// chains. For the canonical code refer to: https://github.com/ethereum/go-ethereum/blob/master/consensus/misc/eip1559.go
+func (k Keeper) CalculateBaseFee(ctx sdk.Context) *big.Int {
+	params := k.GetParams(ctx)
+
+	if params.NoBaseFee {
+		return nil
+	}
+
+	consParams := ctx.ConsensusParams()
+
+	// If the current block is the first EIP-1559 block, return the InitialBaseFee.
+	if ctx.BlockHeight() <= params.EnableHeight {
+		return new(big.Int).SetInt64(params.InitialBaseFee)
+	}
+
+	// get the block gas used and the base fee values for the parent block.
+	parentBaseFee := k.GetBaseFee(ctx)
+	if parentBaseFee == nil {
+		parentBaseFee = new(big.Int).SetInt64(params.InitialBaseFee)
+	}
+
+	parentGasUsed := k.GetBlockGasUsed(ctx)
+
+	gasLimit := new(big.Int).SetUint64(math.MaxUint64)
+	if consParams != nil && consParams.Block.MaxGas > -1 {
+		gasLimit = big.NewInt(consParams.Block.MaxGas)
+	}
+
+	parentGasTargetBig := new(big.Int).Div(gasLimit, new(big.Int).SetUint64(uint64(params.ElasticityMultiplier)))
+	if !parentGasTargetBig.IsUint64() {
+		return new(big.Int).SetInt64(params.InitialBaseFee)
+	}
+
+	parentGasTarget := parentGasTargetBig.Uint64()
+	baseFeeChangeDenominator := new(big.Int).SetUint64(uint64(params.BaseFeeChangeDenominator))
+
+	// If the parent gasUsed is the same as the target, the baseFee remains unchanged.
+	if parentGasUsed == parentGasTarget {
+		return new(big.Int).Set(parentBaseFee)
+	}
+
+	if parentGasUsed > parentGasTarget {
+		// If the parent block used more gas than its target, the baseFee should increase.
+		gasUsedDelta := new(big.Int).SetUint64(parentGasUsed - parentGasTarget)
+		x := new(big.Int).Mul(parentBaseFee, gasUsedDelta)
+		y := x.Div(x, parentGasTargetBig)
+		baseFeeDelta := math.BigMax(
+			x.Div(y, baseFeeChangeDenominator),
+			common.Big1,
+		)
+
+		return x.Add(parentBaseFee, baseFeeDelta)
+	}
+
+	// Otherwise if the parent block used less gas than its target, the baseFee should decrease.
+	gasUsedDelta := new(big.Int).SetUint64(parentGasTarget - parentGasUsed)
+	x := new(big.Int).Mul(parentBaseFee, gasUsedDelta)
+	y := x.Div(x, parentGasTargetBig)
+	baseFeeDelta := x.Div(y, baseFeeChangeDenominator)
+
+	return math.BigMax(
+		x.Sub(parentBaseFee, baseFeeDelta),
+		common.Big0,
+	)
+}