Add minimum commission rate to x/staking (#3)

* add minimum commission rate * fixed DefaultMinCommissionRate comment * Update x/staking/keeper/params.go * Update x/staking/keeper/validator.go * Update x/staking/keeper/validator_test.go * Update x/staking/keeper/validator_test.go Co-authored-by: Dev Ojha <ValarDragon@users.noreply.github.com> * Update x/staking/keeper/validator_test.go * fix lint * make proto-all * fix lint * add powerreduction to params * check protobuf breakage against osmo-v0.42.x instead of master Co-authored-by: Dev Ojha <ValarDragon@users.noreply.github.com>
osmosis-labs · Jan 23, 2022 · c3f499c · c3f499c
1 parent b6c77e6
commit c3f499c
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Showing 13 changed files with 1,664 additions and 1,455 deletions.
diff --git a/Makefile b/Makefile
@@ -10,7 +10,7 @@ BINDIR ?= $(GOPATH)/bin
 BUILDDIR ?= $(CURDIR)/build
 SIMAPP = ./simapp
 MOCKS_DIR = $(CURDIR)/tests/mocks
-HTTPS_GIT := https://github.com/cosmos/cosmos-sdk.git
+HTTPS_GIT := https://github.com/osmosis-labs/cosmos-sdk.git
 DOCKER := $(shell which docker)
 DOCKER_BUF := $(DOCKER) run --rm -v $(CURDIR):/workspace --workdir /workspace bufbuild/buf
 
@@ -415,7 +415,7 @@ proto-lint:
 	@$(DOCKER_BUF) lint --error-format=json
 
 proto-check-breaking:
-	@$(DOCKER_BUF) breaking --against $(HTTPS_GIT)#branch=master
+	@$(DOCKER_BUF) breaking --against $(HTTPS_GIT)#branch=osmo-v0.42.x
 
 
 TM_URL              = https://raw.githubusercontent.com/tendermint/tendermint/v0.34.0-rc6/proto/tendermint

diff --git a/docs/core/proto-docs.md b/docs/core/proto-docs.md
@@ -6428,6 +6428,7 @@ Params defines the parameters for the staking module.
 | `max_entries` | [uint32](#uint32) |  | max_entries is the max entries for either unbonding delegation or redelegation (per pair/trio). |
 | `historical_entries` | [uint32](#uint32) |  | historical_entries is the number of historical entries to persist. |
 | `bond_denom` | [string](#string) |  | bond_denom defines the bondable coin denomination. |
+| `min_commission_rate` | [string](#string) |  | min_commission_rate is the chain-wide minimum commission rate that a validator can charge their delegators |
 
 
 

diff --git a/proto/cosmos/staking/v1beta1/staking.proto b/proto/cosmos/staking/v1beta1/staking.proto
@@ -282,6 +282,12 @@ message Params {
   uint32 historical_entries = 4 [(gogoproto.moretags) = "yaml:\"historical_entries\""];
   // bond_denom defines the bondable coin denomination.
   string bond_denom = 5 [(gogoproto.moretags) = "yaml:\"bond_denom\""];
+  // min_commission_rate is the chain-wide minimum commission rate that a validator can charge their delegators
+  string min_commission_rate = 6 [
+    (gogoproto.moretags)   = "yaml:\"min_commission_rate\"",
+    (gogoproto.customtype) = "github.com/cosmos/cosmos-sdk/types.Dec",
+    (gogoproto.nullable)   = false
+  ];
 }
 
 // DelegationResponse is equivalent to Delegation except that it contains a

diff --git a/x/staking/client/testutil/suite.go b/x/staking/client/testutil/suite.go
@@ -876,12 +876,13 @@ func (s *IntegrationTestSuite) TestGetCmdQueryParams() {
 historical_entries: 10000
 max_entries: 7
 max_validators: 100
+min_commission_rate: "0.000000000000000000"
 unbonding_time: 1814400s`,
 		},
 		{
 			"with json output",
 			[]string{fmt.Sprintf("--%s=json", tmcli.OutputFlag)},
-			`{"unbonding_time":"1814400s","max_validators":100,"max_entries":7,"historical_entries":10000,"bond_denom":"stake"}`,
+			`{"unbonding_time":"1814400s","max_validators":100,"max_entries":7,"historical_entries":10000,"bond_denom":"stake","min_commission_rate":"0.000000000000000000"}`,
 		},
 	}
 	for _, tc := range testCases {

diff --git a/x/staking/keeper/params.go b/x/staking/keeper/params.go
@@ -47,14 +47,21 @@ func (k Keeper) PowerReduction(ctx sdk.Context) sdk.Int {
 	return sdk.DefaultPowerReduction
 }
 
-// Get all parameteras as types.Params
+// MinCommissionRate - Minimum validator commission rate
+func (k Keeper) MinCommissionRate(ctx sdk.Context) (res sdk.Dec) {
+	k.paramstore.Get(ctx, types.KeyMinCommissionRate, &res)
+	return
+}
+
+// Get all parameters as types.Params
 func (k Keeper) GetParams(ctx sdk.Context) types.Params {
 	return types.NewParams(
 		k.UnbondingTime(ctx),
 		k.MaxValidators(ctx),
 		k.MaxEntries(ctx),
 		k.HistoricalEntries(ctx),
 		k.BondDenom(ctx),
+		k.MinCommissionRate(ctx),
 	)
 }
 

diff --git a/x/staking/keeper/validator.go b/x/staking/keeper/validator.go
@@ -138,6 +138,10 @@ func (k Keeper) UpdateValidatorCommission(ctx sdk.Context,
 		return commission, err
 	}
 
+	if newRate.LT(k.MinCommissionRate(ctx)) {
+		return commission, fmt.Errorf("cannot set validator commission to less than minimum rate of %s", k.MinCommissionRate(ctx))
+	}
+
 	commission.Rate = newRate
 	commission.UpdateTime = blockTime
 

diff --git a/x/staking/keeper/validator_test.go b/x/staking/keeper/validator_test.go
@@ -1041,6 +1041,12 @@ func TestUpdateValidatorCommission(t *testing.T) {
 	app, ctx, _, addrVals := bootstrapValidatorTest(t, 1000, 20)
 	ctx = ctx.WithBlockHeader(tmproto.Header{Time: time.Now().UTC()})
 
+	params := app.StakingKeeper.GetParams(ctx)
+
+	params.MinCommissionRate = sdk.MustNewDecFromStr("0.05")
+
+	app.StakingKeeper.SetParams(ctx, params)
+
 	commission1 := types.NewCommissionWithTime(
 		sdk.NewDecWithPrec(1, 1), sdk.NewDecWithPrec(3, 1),
 		sdk.NewDecWithPrec(1, 1), time.Now().UTC().Add(time.Duration(-1)*time.Hour),
@@ -1065,6 +1071,7 @@ func TestUpdateValidatorCommission(t *testing.T) {
 		{val2, sdk.NewDecWithPrec(-1, 1), true},
 		{val2, sdk.NewDecWithPrec(4, 1), true},
 		{val2, sdk.NewDecWithPrec(3, 1), true},
+		{val2, sdk.NewDecWithPrec(1, 2), true}, // Commission rate below minimum
 		{val2, sdk.NewDecWithPrec(2, 1), false},
 	}
 

diff --git a/x/staking/legacy/v040/migrate.go b/x/staking/legacy/v040/migrate.go
@@ -6,6 +6,7 @@ import (
 	codectypes "github.com/cosmos/cosmos-sdk/codec/types"
 	v034staking "github.com/cosmos/cosmos-sdk/x/staking/legacy/v034"
 	v038staking "github.com/cosmos/cosmos-sdk/x/staking/legacy/v038"
+	v040staking "github.com/cosmos/cosmos-sdk/x/staking/types"
 )
 
 func migrateBondStatus(oldStatus v034staking.BondStatus) BondStatus {
@@ -128,6 +129,7 @@ func Migrate(stakingState v038staking.GenesisState) *GenesisState {
 			MaxEntries:        uint32(stakingState.Params.MaxEntries),
 			HistoricalEntries: uint32(stakingState.Params.HistoricalEntries),
 			BondDenom:         stakingState.Params.BondDenom,
+			MinCommissionRate: v040staking.DefaultMinCommissionRate,
 		},
 		LastTotalPower:       stakingState.LastTotalPower,
 		LastValidatorPowers:  newLastValidatorPowers,

diff --git a/x/staking/legacy/v040/migrate_test.go b/x/staking/legacy/v040/migrate_test.go
@@ -55,6 +55,7 @@ func TestMigrate(t *testing.T) {
     "historical_entries": 0,
     "max_entries": 0,
     "max_validators": 0,
+    "min_commission_rate": "0.000000000000000000",
     "unbonding_time": "0s"
   },
   "redelegations": [],