feat(mint): add DevelopmentFund to block rewards

config.yml

@@ -62,9 +62,17 @@ genesis:
       params:
         mint_denom: "uspn"
         distribution_proportions:
-          staking: "0.400000000000000000"
+          staking: "0.300000000000000000"
           incentives: "0.400000000000000000"
-          community_pool: "0.200000000000000000"
+          development_fund: "0.200000000000000000"
+          community_pool: "0.100000000000000000"
+        development_fund_recipients:
+          - address: "spn1ezptsm3npn54qx9vvpah4nymre59ykr9exx2ul" # alice
+            weight: "0.400000000000000000"
+          - address: "spn1aqn8ynvr3jmq67879qulzrwhchq5dtrvtx0nhe" # bob
+            weight: "0.300000000000000000"
+          - address: "spn1pkdk6m2nh77nlaep84cylmkhjder3arey7rll5" # carol
+            weight: "0.300000000000000000"
     launch:
       params:
         revertDelay: "5"
@@ -73,8 +81,8 @@ genesis:
     fundraising:
       params:
         auction_creation_fee:
-          - "amount": "100"
-            "denom": "uspn"
+          - amount: "100"
+            denom: "uspn"
     monitoringp:
       params:
         lastBlockHeight: "1"

proto/mint/mint.proto

@@ -17,6 +17,14 @@ message Minter {
   ];
 }
 
+message WeightedAddress {
+  string address = 1;
+  string weight = 2 [
+    (gogoproto.customtype) = "github.com/cosmos/cosmos-sdk/types.Dec",
+    (gogoproto.nullable) = false
+  ];
+}
+
 message DistributionProportions {
   // staking defines the proportion of the minted minted_denom that is to be
   // allocated as staking rewards.
@@ -30,9 +38,15 @@ message DistributionProportions {
     (gogoproto.customtype) = "github.com/cosmos/cosmos-sdk/types.Dec",
     (gogoproto.nullable) = false
   ];
+  // development_fund defines the proportion of the minted minted_denom that is
+  // to be allocated for development funding.
+  string development_fund = 3 [
+    (gogoproto.customtype) = "github.com/cosmos/cosmos-sdk/types.Dec",
+    (gogoproto.nullable) = false
+  ];
   // community_pool defines the proportion of the minted minted_denom that is
   // to be allocated to the community pool.
-  string community_pool = 3 [
+  string community_pool = 4 [
     (gogoproto.customtype) = "github.com/cosmos/cosmos-sdk/types.Dec",
     (gogoproto.nullable) = false
   ];
@@ -69,4 +83,9 @@ message Params {
   // distribution_proportions defines the proportion of the minted denom
   DistributionProportions distribution_proportions = 7
   [ (gogoproto.nullable) = false ];
+
+  // address to receive developer rewards
+  repeated WeightedAddress development_fund_recipients = 8 [
+    (gogoproto.nullable) = false
+  ];
 }

x/mint/keeper/keeper.go

@@ -4,6 +4,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/codec"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	paramtypes "github.com/cosmos/cosmos-sdk/x/params/types"
+	spnerrors "github.com/tendermint/spn/pkg/errors"
 	"github.com/tendermint/tendermint/libs/log"
 
 	"github.com/tendermint/spn/x/mint/types"
@@ -140,8 +141,34 @@ func (k Keeper) DistributeMintedCoins(ctx sdk.Context, mintedCoin sdk.Coin) erro
 	//	return err
 	// }
 
+	devFundCoin := k.GetProportions(ctx, mintedCoin, proportions.DevelopmentFund)
+	devFundCoins := sdk.NewCoins(devFundCoin)
+	if len(params.DevelopmentFundRecipients) == 0 {
+		// fund community pool when rewards address is empty
+		if err = k.distrKeeper.FundCommunityPool(
+			ctx,
+			devFundCoins,
+			k.accountKeeper.GetModuleAddress(types.ModuleName),
+		); err != nil {
+			return err
+		}
+	} else {
+		// allocate developer rewards to developer addresses by weight
+		for _, w := range params.DevelopmentFundRecipients {
+			devFundPortionCoins := sdk.NewCoins(k.GetProportions(ctx, devFundCoin, w.Weight))
+			devAddr, err := sdk.AccAddressFromBech32(w.Address)
+			if err != nil {
+				return spnerrors.Critical(err.Error())
+			}
+			err = k.bankKeeper.SendCoinsFromModuleToAccount(ctx, types.ModuleName, devAddr, devFundPortionCoins)
+			if err != nil {
+				return err
+			}
+		}
+	}
+
 	// subtract from original provision to ensure no coins left over after the allocations
-	communityPoolCoins := sdk.NewCoins(mintedCoin).Sub(stakingRewardsCoins).Sub(incentivesCoins)
+	communityPoolCoins := sdk.NewCoins(mintedCoin).Sub(stakingRewardsCoins).Sub(incentivesCoins).Sub(devFundCoins)
 	err = k.distrKeeper.FundCommunityPool(ctx, communityPoolCoins, k.accountKeeper.GetModuleAddress(types.ModuleName))
 	if err != nil {
 		return err

x/mint/simulation/genesis.go

@@ -9,18 +9,21 @@ import (
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/cosmos/cosmos-sdk/types/module"
+	simtypes "github.com/cosmos/cosmos-sdk/types/simulation"
 
+	"github.com/tendermint/spn/testutil/sample"
 	"github.com/tendermint/spn/x/mint/types"
 )
 
 // Simulation parameter constants
 const (
-	Inflation               = "inflation"
-	InflationRateChange     = "inflation_rate_change"
-	InflationMax            = "inflation_max"
-	InflationMin            = "inflation_min"
-	GoalBonded              = "goal_bonded"
-	DistributionProportions = "distribution_proportions"
+	Inflation                 = "inflation"
+	InflationRateChange       = "inflation_rate_change"
+	InflationMax              = "inflation_max"
+	InflationMin              = "inflation_min"
+	GoalBonded                = "goal_bonded"
+	DistributionProportions   = "distribution_proportions"
+	DevelopmentFundRecipients = "development_fund_recipients"
 )
 
 // GenInflation randomized Inflation
@@ -53,15 +56,44 @@ func GenDistributionProportions(r *rand.Rand) types.DistributionProportions {
 	staking := r.Int63n(99)
 	left := int64(100) - staking
 	incentives := r.Int63n(left)
-	communityPool := left - incentives
+	left -= incentives
+	devs := r.Int63n(left)
+	communityPool := left - devs
 
 	return types.DistributionProportions{
-		Staking:       sdk.NewDecWithPrec(staking, 2),
-		Incentives:    sdk.NewDecWithPrec(incentives, 2),
-		CommunityPool: sdk.NewDecWithPrec(communityPool, 2),
+		Staking:         sdk.NewDecWithPrec(staking, 2),
+		Incentives:      sdk.NewDecWithPrec(incentives, 2),
+		DevelopmentFund: sdk.NewDecWithPrec(devs, 2),
+		CommunityPool:   sdk.NewDecWithPrec(communityPool, 2),
 	}
 }
 
+func GenDevelopmentFundRecipients(r *rand.Rand) []types.WeightedAddress {
+	var (
+		addrs         = make([]types.WeightedAddress, 0)
+		numAddrs      = r.Intn(51)
+		remainWeight  = sdk.NewDec(1)
+		maxRandWeight = sdk.NewDecWithPrec(15, 3)
+		minRandWeight = sdk.NewDecWithPrec(5, 3)
+	)
+	for i := 0; i < numAddrs; i++ {
+		// each address except the last can have a max of 2% weight and a min of 0.5%
+		weight := simtypes.RandomDecAmount(r, maxRandWeight).Add(minRandWeight)
+		if i == numAddrs-1 {
+			// use residual weight if last address
+			weight = remainWeight
+		} else {
+			remainWeight = remainWeight.Sub(weight)
+		}
+		wa := types.WeightedAddress{
+			Address: sample.Address(r),
+			Weight:  weight,
+		}
+		addrs = append(addrs, wa)
+	}
+	return addrs
+}
+
 // RandomizedGenState generates a random GenesisState for mint
 func RandomizedGenState(simState *module.SimulationState) {
 	// minter
@@ -102,9 +134,15 @@ func RandomizedGenState(simState *module.SimulationState) {
 		func(r *rand.Rand) { distributionProportions = GenDistributionProportions(r) },
 	)
 
+	var developmentFundRecipients []types.WeightedAddress
+	simState.AppParams.GetOrGenerate(
+		simState.Cdc, DevelopmentFundRecipients, &developmentFundRecipients, simState.Rand,
+		func(r *rand.Rand) { developmentFundRecipients = GenDevelopmentFundRecipients(r) },
+	)
+
 	mintDenom := sdk.DefaultBondDenom
 	blocksPerYear := uint64(60 * 60 * 8766 / 5)
-	params := types.NewParams(mintDenom, inflationRateChange, inflationMax, inflationMin, goalBonded, blocksPerYear, distributionProportions)
+	params := types.NewParams(mintDenom, inflationRateChange, inflationMax, inflationMin, goalBonded, blocksPerYear, distributionProportions, developmentFundRecipients)
 
 	mintGenesis := types.NewGenesisState(types.InitialMinter(inflation), params)