feat(x/gov): dynamic deposit throttler

proto/atomone/gov/v1/genesis.proto

@@ -34,4 +34,7 @@ message GenesisState {
   //
   // Since: cosmos-sdk 0.48
   string constitution = 9;
+
+  // last updated value for the dynamic min deposit
+  LastMinDeposit last_min_deposit = 10;
 }

proto/atomone/gov/v1/gov.proto

@@ -48,6 +48,17 @@ message Deposit {
       [ (gogoproto.nullable) = false, (amino.dont_omitempty) = true ];
 }
 
+// LastMinDeposit is a record of the last time the minimum deposit
+// was updated in the store, both its value and a timestamp
+message LastMinDeposit {
+  // value is the value of the minimum deposit
+  repeated cosmos.base.v1beta1.Coin value = 1
+      [ (gogoproto.nullable) = false, (amino.dont_omitempty) = true ];
+
+  // time is the time the minimum deposit was last updated
+  google.protobuf.Timestamp time = 2 [ (gogoproto.stdtime) = true ];
+}
+
 // Proposal defines the core field members of a governance proposal.
 message Proposal {
   // id defines the unique id of the proposal.
@@ -208,13 +219,45 @@ message TallyParams {
   string law_threshold = 6 [(cosmos_proto.scalar) = "cosmos.Dec"];
 }
 
+message MinDepositThrottler {
+  // Floor value for the minimum deposit required for a proposal to enter the voting period.
+  repeated cosmos.base.v1beta1.Coin floor_value = 1
+  [ (gogoproto.nullable) = false, (amino.dont_omitempty) = true ];
+
+  // Duration that dictates after how long the dynamic minimum deposit should be recalculated
+  // for time-based updates.
+  google.protobuf.Duration update_period = 2 [(gogoproto.stdduration) = true];
+
+  // The number of active proposals the dynamic minimum deposit should target.
+  uint64 target_active_proposals = 3;
+
+  // The ratio of increase for the minimum deposit when the number of active proposals
+  // exceeds the target by 1.
+  string increase_ratio = 4 [(cosmos_proto.scalar) = "cosmos.Dec"];
+
+  // The ratio of decrease for the minimum deposit when the number of active proposals
+  // is 1 less than the target.
+  string decrease_ratio = 5 [(cosmos_proto.scalar) = "cosmos.Dec"];
+
+  // A positive integer representing the sensitivity of the dynamic minimum deposit 
+  // increase/decrease to the distance from the target number of active proposals.
+  // The higher the number, the lower the sensitivity. A value of 1 represents the
+  // highest sensitivity.
+  uint64 sensitivity_target_distance = 6;
+}
+
 // Params defines the parameters for the x/gov module.
 //
 // Since: cosmos-sdk 0.47
 message Params {
   // Minimum deposit for a proposal to enter voting period.
+  // Deprecated: a dynamic system now determines the minimum deposit,
+  // see the other params inside the min_deposit_throttler field.
+  // While setting this value returns an error, when queried it is set to the
+  // value of the current minimum deposit value as determined by the dynamic
+  // system for backward compatibility.
   repeated cosmos.base.v1beta1.Coin min_deposit = 1
-      [ (gogoproto.nullable) = false, (amino.dont_omitempty) = true ];
+      [ (gogoproto.nullable) = false, (amino.dont_omitempty) = true, deprecated = true ];
 
   // Maximum period for Atom holders to deposit on a proposal. Initial value: 2
   // months.
@@ -272,4 +315,6 @@ message Params {
   // Number of times a proposal should be checked for quorum after the quorum timeout
   // has elapsed. Used to compute the amount of time in between quorum checks.
   uint64 quorum_check_count = 22;
+
+  MinDepositThrottler min_deposit_throttler = 23;
 }

proto/atomone/gov/v1/query.proto

@@ -3,6 +3,8 @@
 syntax = "proto3";
 package atomone.gov.v1;
 
+import "cosmos/base/v1beta1/coin.proto";
+import "gogoproto/gogo.proto";
 import "cosmos/base/query/v1beta1/pagination.proto";
 import "google/api/annotations.proto";
 import "atomone/gov/v1/gov.proto";
@@ -61,6 +63,12 @@ service Query {
     option (google.api.http).get =
         "/atomone/gov/v1/proposals/{proposal_id}/tally";
   }
+
+  // MinDeposit queries the minimum deposit currently
+  // required for a proposal to enter voting period.
+  rpc MinDeposit(QueryMinDepositRequest) returns (QueryMinDepositResponse) {
+    option (google.api.http).get = "/atomone/gov/v1/mindeposit";
+  }
 }
 
 // QueryConstitutionRequest is the request type for the Query/Constitution RPC method
@@ -209,3 +217,12 @@ message QueryTallyResultResponse {
   // tally defines the requested tally.
   TallyResult tally = 1;
 }
+
+// QueryMinDepositRequest is the request type for the Query/MinDeposit RPC method.
+message QueryMinDepositRequest {}
+
+// QueryMinDepositResponse is the response type for the Query/MinDeposit RPC method.
+message QueryMinDepositResponse {
+  // min_deposit defines the minimum deposit required for a proposal to enter voting period.
+  repeated cosmos.base.v1beta1.Coin min_deposit = 1 [ (gogoproto.nullable) = false];
+}

tests/e2e/genesis.go

@@ -179,13 +179,18 @@ func modifyGenesis(path, moniker, amountStr string, addrAll []sdk.AccAddress, de
 
 	govGenState := govv1.NewGenesisState(1,
 		govv1.NewParams(
-			sdk.NewCoins(sdk.NewCoin(denom, amnt)), maxDepositPeriod,
+			// sdk.NewCoins(sdk.NewCoin(denom, amnt)),
+			maxDepositPeriod,
 			votingPeriod,
 			quorum.String(), threshold.String(),
 			amendmentsQuorum.String(), amendmentsThreshold.String(), lawQuorum.String(), lawThreshold.String(),
 			sdk.ZeroDec().String(),
 			false, false, govv1.DefaultMinDepositRatio.String(),
 			govv1.DefaultQuorumTimeout, govv1.DefaultMaxVotingPeriodExtension, govv1.DefaultQuorumCheckCount,
+			sdk.NewCoins(sdk.NewCoin(denom, amnt)), govv1.DefaultMinDepositUpdatePeriod,
+			govv1.DefaultMinDepositSensitivityTargetDistance,
+			govv1.DefaultMinDepositIncreaseRatio.String(), govv1.DefaultMinDepositDecreaseRatio.String(),
+			govv1.DefaultTargetActiveProposals,
 		),
 	)
 	govGenState.Constitution = "This is a test constitution"

x/gov/abci.go

@@ -22,6 +22,14 @@ func EndBlocker(ctx sdk.Context, keeper *keeper.Keeper) {
 	// delete dead proposals from store and returns theirs deposits.
 	// A proposal is dead when it's inactive and didn't get enough deposit on time to get into voting phase.
 	keeper.IterateInactiveProposalsQueue(ctx, ctx.BlockHeader().Time, func(proposal v1.Proposal) bool {
+		// before deleting, check one last time if the proposal has enough deposits to get into voting phase,
+		// maybe because min deposit decreased in the meantime.
+		minDeposit := keeper.GetMinDeposit(ctx)
+		if proposal.Status == v1.StatusDepositPeriod && sdk.NewCoins(proposal.TotalDeposit...).IsAllGTE(minDeposit) {
+			keeper.ActivateVotingPeriod(ctx, proposal)
+			return false
+		}
+
 		keeper.DeleteProposal(ctx, proposal.Id)
 
 		params := keeper.GetParams(ctx)
@@ -45,7 +53,7 @@ func EndBlocker(ctx sdk.Context, keeper *keeper.Keeper) {
 		logger.Info(
 			"proposal did not meet minimum deposit; deleted",
 			"proposal", proposal.Id,
-			"min_deposit", sdk.NewCoins(params.MinDeposit...).String(),
+			"min_deposit", sdk.NewCoins(minDeposit...).String(),
 			"total_deposit", sdk.NewCoins(proposal.TotalDeposit...).String(),
 		)
 
@@ -190,6 +198,7 @@ func EndBlocker(ctx sdk.Context, keeper *keeper.Keeper) {
 
 		keeper.SetProposal(ctx, proposal)
 		keeper.RemoveFromActiveProposalQueue(ctx, proposal.Id, *proposal.VotingEndTime)
+		keeper.DecrementActiveProposalsNumber(ctx)
 
 		// when proposal become active
 		keeper.Hooks().AfterProposalVotingPeriodEnded(ctx, proposal.Id)

x/gov/abci_test.go

@@ -276,6 +276,7 @@ func TestTickPassedVotingPeriod(t *testing.T) {
 	activeQueue = suite.GovKeeper.ActiveProposalQueueIterator(ctx, ctx.BlockHeader().Time)
 	require.True(t, activeQueue.Valid())
 
+	require.EqualValues(t, 1, suite.GovKeeper.GetActiveProposalsNumber(ctx))
 	activeProposalID := types.GetProposalIDFromBytes(activeQueue.Value())
 	proposal, ok := suite.GovKeeper.GetProposal(ctx, activeProposalID)
 	require.True(t, ok)
@@ -285,6 +286,7 @@ func TestTickPassedVotingPeriod(t *testing.T) {
 
 	gov.EndBlocker(ctx, suite.GovKeeper)
 
+	require.EqualValues(t, 0, suite.GovKeeper.GetActiveProposalsNumber(ctx))
 	activeQueue = suite.GovKeeper.ActiveProposalQueueIterator(ctx, ctx.BlockHeader().Time)
 	require.False(t, activeQueue.Valid())
 	activeQueue.Close()
@@ -379,10 +381,12 @@ func TestEndBlockerProposalHandlerFailed(t *testing.T) {
 	newHeader := ctx.BlockHeader()
 	newHeader.Time = ctx.BlockHeader().Time.Add(*suite.GovKeeper.GetParams(ctx).MaxDepositPeriod).Add(*suite.GovKeeper.GetParams(ctx).VotingPeriod)
 	ctx = ctx.WithBlockHeader(newHeader)
+	require.EqualValues(t, 1, suite.GovKeeper.GetActiveProposalsNumber(ctx))
 
 	// validate that the proposal fails/has been rejected
 	gov.EndBlocker(ctx, suite.GovKeeper)
 
+	require.EqualValues(t, 0, suite.GovKeeper.GetActiveProposalsNumber(ctx))
 	proposal, ok := suite.GovKeeper.GetProposal(ctx, proposal.Id)
 	require.True(t, ok)
 	require.Equal(t, v1.StatusFailed, proposal.Status)
@@ -483,7 +487,7 @@ func TestEndBlockerQuorumCheck(t *testing.T) {
 			require.NoError(t, err)
 			require.NotNil(t, res)
 			// Activate proposal
-			newDepositMsg := v1.NewMsgDeposit(addrs[1], res.ProposalId, params.MinDeposit)
+			newDepositMsg := v1.NewMsgDeposit(addrs[1], res.ProposalId, suite.GovKeeper.GetMinDeposit(ctx))
 			res1, err := govMsgSvr.Deposit(ctx, newDepositMsg)
 			require.NoError(t, err)
 			require.NotNil(t, res1)

x/gov/client/cli/query.go

@@ -40,6 +40,7 @@ func GetQueryCmd() *cobra.Command {
 		GetCmdQueryDeposits(),
 		GetCmdQueryTally(),
 		GetCmdConstitution(),
+		GetCmdQueryMinDeposit(),
 	)
 
 	return govQueryCmd
@@ -676,3 +677,35 @@ func GetCmdConstitution() *cobra.Command {
 		},
 	}
 }
+
+// GetCmdQueryMinDeposit implements the query min deposit command.
+func GetCmdQueryMinDeposit() *cobra.Command {
+	return &cobra.Command{
+		Use:   "min-deposit",
+		Args:  cobra.ExactArgs(0),
+		Short: "Query the minimum deposit currently needed for a proposal to enter voting period",
+		Long: strings.TrimSpace(
+			fmt.Sprintf(`Query the minimum deposit needed for a proposal to enter voting period.
+
+Example:
+$ %s query gov min-deposit
+`,
+				version.AppName,
+			),
+		),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			clientCtx, err := client.GetClientTxContext(cmd)
+			if err != nil {
+				return err
+			}
+			queryClient := v1.NewQueryClient(clientCtx)
+
+			resp, err := queryClient.MinDeposit(cmd.Context(), &v1.QueryMinDepositRequest{})
+			if err != nil {
+				return err
+			}
+
+			return clientCtx.PrintProto(resp)
+		},
+	}
+}

x/gov/genesis.go

@@ -77,6 +77,12 @@ func InitGenesis(ctx sdk.Context, ak types.AccountKeeper, bk types.BankKeeper, k
 	if !balance.IsEqual(totalDeposits) {
 		panic(fmt.Sprintf("expected module account was %s but we got %s", balance.String(), totalDeposits.String()))
 	}
+
+	if data.LastMinDeposit != nil {
+		k.SetLastMinDeposit(ctx, data.LastMinDeposit.Value, *data.LastMinDeposit.Time)
+	} else {
+		k.SetLastMinDeposit(ctx, data.Params.MinDepositThrottler.FloorValue, ctx.BlockTime())
+	}
 }
 
 // ExportGenesis - output genesis parameters
@@ -96,12 +102,19 @@ func ExportGenesis(ctx sdk.Context, k *keeper.Keeper) *v1.GenesisState {
 		proposalsVotes = append(proposalsVotes, votes...)
 	}
 
+	blockTime := ctx.BlockTime()
+	lastMinDeposit := v1.LastMinDeposit{
+		Value: k.GetMinDeposit(ctx),
+		Time:  &blockTime,
+	}
+
 	return &v1.GenesisState{
 		StartingProposalId: startingProposalID,
 		Deposits:           proposalsDeposits,
 		Votes:              proposalsVotes,
 		Proposals:          proposals,
 		Params:             &params,
 		Constitution:       constitution,
+		LastMinDeposit:     &lastMinDeposit,
 	}
 }

x/gov/genesis_test.go

@@ -26,6 +26,11 @@ func TestImportExportQueues_ErrorUnconsistentState(t *testing.T) {
 	suite := createTestSuite(t)
 	app := suite.App
 	ctx := app.BaseApp.NewContext(false, tmproto.Header{})
+	expectedGenState := v1.DefaultGenesisState()
+	expectedGenState.LastMinDeposit = &v1.LastMinDeposit{
+		Value: sdk.NewCoins(expectedGenState.Params.MinDepositThrottler.FloorValue...),
+		Time:  &time.Time{},
+	}
 	require.Panics(t, func() {
 		gov.InitGenesis(ctx, suite.AccountKeeper, suite.BankKeeper, suite.GovKeeper, &v1.GenesisState{
 			Deposits: v1.Deposits{
@@ -44,20 +49,24 @@ func TestImportExportQueues_ErrorUnconsistentState(t *testing.T) {
 	})
 	gov.InitGenesis(ctx, suite.AccountKeeper, suite.BankKeeper, suite.GovKeeper, v1.DefaultGenesisState())
 	genState := gov.ExportGenesis(ctx, suite.GovKeeper)
-	require.Equal(t, genState, v1.DefaultGenesisState())
+	require.Equal(t, genState, expectedGenState)
 }
 
 func TestInitGenesis(t *testing.T) {
 	var (
 		testAddrs = simtestutil.CreateRandomAccounts(2)
 		params    = &v1.Params{
-			MinDeposit: sdk.NewCoins(sdk.NewCoin(sdk.DefaultBondDenom, sdkmath.NewInt(42))),
+			MinDepositThrottler: &v1.MinDepositThrottler{
+				FloorValue: sdk.NewCoins(sdk.NewCoin(sdk.DefaultBondDenom, sdkmath.NewInt(42))),
+			},
 		}
 		quorumTimeout                = time.Hour * 20
 		paramsWithQuorumCheckEnabled = &v1.Params{
-			MinDeposit:       sdk.NewCoins(sdk.NewCoin(sdk.DefaultBondDenom, sdkmath.NewInt(42))),
 			QuorumCheckCount: 10,
 			QuorumTimeout:    &quorumTimeout,
+			MinDepositThrottler: &v1.MinDepositThrottler{
+				FloorValue: sdk.NewCoins(sdk.NewCoin(sdk.DefaultBondDenom, sdkmath.NewInt(42))),
+			},
 		}
 
 		depositAmount = sdk.Coins{
@@ -90,6 +99,7 @@ func TestInitGenesis(t *testing.T) {
 				Options:    v1.NewNonSplitVoteOption(v1.OptionNo),
 			},
 		}
+		utcTime         = time.Now().UTC()
 		depositEndTime  = time.Now().Add(time.Hour * 8)
 		votingStartTime = time.Now()
 		votingEndTime   = time.Now().Add(time.Hour * 24)
@@ -162,6 +172,25 @@ func TestInitGenesis(t *testing.T) {
 				t.Helper()
 				p := s.GovKeeper.GetParams(ctx)
 				assert.Equal(t, *params, p)
+				lmdCoins, lmdTime := s.GovKeeper.GetLastMinDeposit(ctx)
+				assert.EqualValues(t, p.MinDepositThrottler.FloorValue, lmdCoins)
+				assert.Equal(t, ctx.BlockTime(), lmdTime)
+			},
+		},
+		{
+			name: "ok: genesis with last min deposit",
+			genesis: v1.GenesisState{
+				Params: params,
+				LastMinDeposit: &v1.LastMinDeposit{
+					Value: sdk.NewCoins(sdk.NewInt64Coin("xxx", 1)),
+					Time:  &utcTime,
+				},
+			},
+			assert: func(t *testing.T, ctx sdk.Context, s suite) {
+				t.Helper()
+				lmdCoins, lmdTime := s.GovKeeper.GetLastMinDeposit(ctx)
+				assert.EqualValues(t, sdk.NewCoins(sdk.NewInt64Coin("xxx", 1)), lmdCoins)
+				assert.Equal(t, utcTime, lmdTime)
 			},
 		},
 		{