Add /incentive/apy query endpoint (#1328)

* Add /incentive/apy query endpoint

* Add APY calculation using usd value

* Fix maths for adding bkava incentive rewards

Signed-off-by: drklee3 <derrick@dlee.dev>

* Fix apy calculation with community tax, remove infra tax

* Fix pricefeed market mismatches, fix division by zero

* Remove unused kavadist expected keeper

Signed-off-by: drklee3 <derrick@dlee.dev>

app/app.go

@@ -633,6 +633,9 @@ func NewApp(
 		&savingsKeeper,
 		&app.liquidKeeper,
 		&earnKeeper,
+		app.mintKeeper,
+		app.distrKeeper,
+		app.pricefeedKeeper,
 	)
 	app.routerKeeper = routerkeeper.NewKeeper(
 		&app.earnKeeper,

x/incentive/client/rest/query.go

@@ -19,6 +19,7 @@ func registerQueryRoutes(cliCtx client.Context, r *mux.Router) {
 	r.HandleFunc(fmt.Sprintf("/%s/rewards", types.ModuleName), queryRewardsHandlerFn(cliCtx)).Methods("GET")
 	r.HandleFunc(fmt.Sprintf("/%s/parameters", types.ModuleName), queryParamsHandlerFn(cliCtx)).Methods("GET")
 	r.HandleFunc(fmt.Sprintf("/%s/reward-factors", types.ModuleName), queryRewardFactorsHandlerFn(cliCtx)).Methods("GET")
+	r.HandleFunc(fmt.Sprintf("/%s/apy", types.ModuleName), queryAPYsHandlerFn(cliCtx)).Methods("GET")
 }
 
 func queryRewardsHandlerFn(cliCtx client.Context) http.HandlerFunc {
@@ -273,3 +274,23 @@ func executeAllRewardQueries(w http.ResponseWriter, cliCtx client.Context, param
 
 	rest.PostProcessResponse(w, cliCtx, resBz)
 }
+
+func queryAPYsHandlerFn(cliCtx client.Context) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		cliCtx, ok := rest.ParseQueryHeightOrReturnBadRequest(w, cliCtx, r)
+		if !ok {
+			return
+		}
+
+		route := fmt.Sprintf("custom/%s/%s", types.ModuleName, types.QueryGetAPYs)
+
+		res, height, err := cliCtx.QueryWithData(route, nil)
+		if err != nil {
+			rest.WriteErrorResponse(w, http.StatusInternalServerError, err.Error())
+			return
+		}
+
+		cliCtx = cliCtx.WithHeight(height)
+		rest.PostProcessResponse(w, cliCtx, res)
+	}
+}

x/incentive/keeper/keeper.go

@@ -24,6 +24,11 @@ type Keeper struct {
 	savingsKeeper types.SavingsKeeper
 	liquidKeeper  types.LiquidKeeper
 	earnKeeper    types.EarnKeeper
+
+	// Keepers used for APY queries
+	mintKeeper      types.MintKeeper
+	distrKeeper     types.DistrKeeper
+	pricefeedKeeper types.PricefeedKeeper
 }
 
 // NewKeeper creates a new keeper
@@ -31,6 +36,7 @@ func NewKeeper(
 	cdc codec.Codec, key sdk.StoreKey, paramstore types.ParamSubspace, bk types.BankKeeper,
 	cdpk types.CdpKeeper, hk types.HardKeeper, ak types.AccountKeeper, stk types.StakingKeeper,
 	swpk types.SwapKeeper, svk types.SavingsKeeper, lqk types.LiquidKeeper, ek types.EarnKeeper,
+	mk types.MintKeeper, dk types.DistrKeeper, pfk types.PricefeedKeeper,
 ) Keeper {
 	if !paramstore.HasKeyTable() {
 		paramstore = paramstore.WithKeyTable(types.ParamKeyTable())
@@ -49,6 +55,9 @@ func NewKeeper(
 		savingsKeeper:   svk,
 		liquidKeeper:    lqk,
 		earnKeeper:      ek,
+		mintKeeper:      mk,
+		distrKeeper:     dk,
+		pricefeedKeeper: pfk,
 	}
 }
 

x/incentive/keeper/querier.go

@@ -1,13 +1,21 @@
 package keeper
 
 import (
+	"fmt"
+
 	"github.com/cosmos/cosmos-sdk/client"
 	"github.com/cosmos/cosmos-sdk/codec"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
 	abci "github.com/tendermint/tendermint/abci/types"
 
+	earntypes "github.com/kava-labs/kava/x/earn/types"
 	"github.com/kava-labs/kava/x/incentive/types"
+	liquidtypes "github.com/kava-labs/kava/x/liquid/types"
+)
+
+const (
+	SecondsPerYear = 31536000
 )
 
 // NewQuerier is the module level router for state queries
@@ -31,6 +39,8 @@ func NewQuerier(k Keeper, legacyQuerierCdc *codec.LegacyAmino) sdk.Querier {
 			return queryGetRewardFactors(ctx, req, k, legacyQuerierCdc)
 		case types.QueryGetEarnRewards:
 			return queryGetEarnRewards(ctx, req, k, legacyQuerierCdc)
+		case types.QueryGetAPYs:
+			return queryGetAPYs(ctx, req, k, legacyQuerierCdc)
 		default:
 			return nil, sdkerrors.Wrapf(sdkerrors.ErrUnknownRequest, "unknown %s query endpoint", types.ModuleName)
 		}
@@ -368,3 +378,156 @@ func queryGetRewardFactors(ctx sdk.Context, req abci.RequestQuery, k Keeper, leg
 
 	return bz, nil
 }
+
+func queryGetAPYs(ctx sdk.Context, req abci.RequestQuery, k Keeper, legacyQuerierCdc *codec.LegacyAmino) ([]byte, error) {
+	params := k.GetParams(ctx)
+	var apys types.APYs
+
+	// bkava APY (staking + incentive rewards)
+	stakingAPR, err := GetStakingAPR(ctx, k, params)
+	if err != nil {
+		return nil, err
+	}
+
+	apys = append(apys, types.NewAPY(liquidtypes.DefaultDerivativeDenom, stakingAPR))
+
+	// Incentive only APYs
+	for _, param := range params.EarnRewardPeriods {
+		// Skip bkava as it's calculated earlier with staking rewards
+		if param.CollateralType == liquidtypes.DefaultDerivativeDenom {
+			continue
+		}
+
+		// Value in the vault in the same denom as CollateralType
+		vaultTotalValue, err := k.earnKeeper.GetVaultTotalValue(ctx, param.CollateralType)
+		if err != nil {
+			return nil, err
+		}
+		apy, err := GetAPYFromMultiRewardPeriod(ctx, k, param.CollateralType, param, vaultTotalValue.Amount)
+		if err != nil {
+			return nil, err
+		}
+
+		apys = append(apys, types.NewAPY(param.CollateralType, apy))
+	}
+
+	// Marshal APYs
+	res := types.NewQueryGetAPYsResponse(apys)
+	bz, err := codec.MarshalJSONIndent(legacyQuerierCdc, res)
+	if err != nil {
+		return nil, sdkerrors.Wrap(sdkerrors.ErrJSONMarshal, err.Error())
+	}
+	return bz, nil
+}
+
+// GetStakingAPR returns the total APR for staking and incentive rewards
+func GetStakingAPR(ctx sdk.Context, k Keeper, params types.Params) (sdk.Dec, error) {
+	// Get staking APR + incentive APR
+	inflationRate := k.mintKeeper.GetMinter(ctx).Inflation
+	communityTax := k.distrKeeper.GetCommunityTax(ctx)
+
+	bondedTokens := k.stakingKeeper.TotalBondedTokens(ctx)
+	circulatingSupply := k.bankKeeper.GetSupply(ctx, types.BondDenom)
+
+	// Staking APR = (Inflation Rate * (1 - Community Tax)) / (Bonded Tokens / Circulating Supply)
+	stakingAPR := inflationRate.
+		Mul(sdk.OneDec().Sub(communityTax)).
+		Quo(bondedTokens.ToDec().
+			Quo(circulatingSupply.Amount.ToDec()))
+
+	// Get incentive APR
+	bkavaRewardPeriod, found := params.EarnRewardPeriods.GetMultiRewardPeriod(liquidtypes.DefaultDerivativeDenom)
+	if !found {
+		// No incentive rewards for bkava, only staking rewards
+		return stakingAPR, nil
+	}
+
+	// Total amount of bkava in earn vaults, this may be lower than total bank
+	// supply of bkava as some bkava may not be deposited in earn vaults
+	totalEarnBkavaDeposited := sdk.ZeroInt()
+
+	var iterErr error
+	k.earnKeeper.IterateVaultRecords(ctx, func(record earntypes.VaultRecord) (stop bool) {
+		if !k.liquidKeeper.IsDerivativeDenom(ctx, record.TotalShares.Denom) {
+			return false
+		}
+
+		vaultValue, err := k.earnKeeper.GetVaultTotalValue(ctx, record.TotalShares.Denom)
+		if err != nil {
+			iterErr = err
+			return false
+		}
+
+		totalEarnBkavaDeposited = totalEarnBkavaDeposited.Add(vaultValue.Amount)
+
+		return false
+	})
+
+	if iterErr != nil {
+		return sdk.ZeroDec(), iterErr
+	}
+
+	// Incentive APR = rewards per second * seconds per year / total supplied to earn vaults
+	// Override collateral type to use "kava" instead of "bkava" when fetching
+	incentiveAPY, err := GetAPYFromMultiRewardPeriod(ctx, k, types.BondDenom, bkavaRewardPeriod, totalEarnBkavaDeposited)
+	if err != nil {
+		return sdk.ZeroDec(), err
+	}
+
+	totalAPY := stakingAPR.Add(incentiveAPY)
+	return totalAPY, nil
+}
+
+// GetAPYFromMultiRewardPeriod calculates the APY for a given MultiRewardPeriod
+func GetAPYFromMultiRewardPeriod(
+	ctx sdk.Context,
+	k Keeper,
+	collateralType string,
+	rewardPeriod types.MultiRewardPeriod,
+	totalSupply sdk.Int,
+) (sdk.Dec, error) {
+	if totalSupply.IsZero() {
+		return sdk.ZeroDec(), nil
+	}
+
+	// Get USD value of collateral type
+	collateralUSDValue, err := k.pricefeedKeeper.GetCurrentPrice(ctx, getMarketID(collateralType))
+	if err != nil {
+		return sdk.ZeroDec(), err
+	}
+
+	// Total USD value of the collateral type total supply
+	totalSupplyUSDValue := totalSupply.ToDec().Mul(collateralUSDValue.Price)
+
+	totalUSDRewardsPerSecond := sdk.ZeroDec()
+
+	// In many cases, RewardsPerSecond are assets that are different from the
+	// CollateralType, so we need to use the USD value of CollateralType and
+	// RewardsPerSecond to determine the APY.
+	for _, reward := range rewardPeriod.RewardsPerSecond {
+		// Get USD value of 1 unit of reward asset type, using TWAP
+		rewardDenomUSDValue, err := k.pricefeedKeeper.GetCurrentPrice(ctx, getMarketID(reward.Denom))
+		if err != nil {
+			return sdk.ZeroDec(), fmt.Errorf("failed to get price for RewardsPerSecond asset %s: %w", reward.Denom, err)
+		}
+
+		rewardPerSecond := reward.Amount.ToDec().Mul(rewardDenomUSDValue.Price)
+		totalUSDRewardsPerSecond = totalUSDRewardsPerSecond.Add(rewardPerSecond)
+	}
+
+	// APY = USD rewards per second * seconds per year / USD total supplied
+	apy := totalUSDRewardsPerSecond.
+		MulInt64(SecondsPerYear).
+		Quo(totalSupplyUSDValue)
+
+	return apy, nil
+}
+
+func getMarketID(denom string) string {
+	if denom == types.BondDenom {
+		// Rewrite "ukava" to "kava" as pricefeed only has "kava" and not "ukava"
+		return getMarketID("kava")
+	}
+
+	return fmt.Sprintf("%s:usd:30", denom)
+}

x/incentive/keeper/querier_test.go

@@ -0,0 +1,102 @@
+package keeper_test
+
+import (
+	"testing"
+	"time"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	minttypes "github.com/cosmos/cosmos-sdk/x/mint/types"
+	pricefeedtypes "github.com/kava-labs/kava/x/pricefeed/types"
+
+	earntypes "github.com/kava-labs/kava/x/earn/types"
+	"github.com/kava-labs/kava/x/incentive/keeper"
+	"github.com/kava-labs/kava/x/incentive/types"
+	"github.com/stretchr/testify/suite"
+)
+
+type QuerierTestSuite struct {
+	unitTester
+}
+
+func TestQuerierTestSuite(t *testing.T) {
+	suite.Run(t, new(QuerierTestSuite))
+}
+
+func (suite *QuerierTestSuite) TestGetStakingAPR() {
+	communityTax := sdk.MustNewDecFromStr("0.90")
+	inflation := sdk.MustNewDecFromStr("0.75")
+
+	bondedTokens := int64(120_000_000_000000)
+	liquidStakedTokens := int64(60_000_000_000000)
+	totalSupply := int64(289_138_414_286684)
+
+	suite.keeper = suite.NewTestKeeper(&fakeParamSubspace{}).
+		WithDistrKeeper(
+			newFakeDistrKeeper().setCommunityTax(communityTax),
+		).
+		WithMintKeeper(
+			newFakeMintKeeper().
+				setMinter(minttypes.NewMinter(inflation, sdk.OneDec())),
+		).
+		WithStakingKeeper(
+			newFakeStakingKeeper().addBondedTokens(bondedTokens),
+		).
+		WithBankKeeper(
+			newFakeBankKeeper().setSupply(sdk.NewCoin(types.BondDenom, sdk.NewInt(totalSupply))),
+		).
+		WithEarnKeeper(
+			newFakeEarnKeeper().
+				addVault("bkava-asdf", earntypes.NewVaultShare("bkava-asdf", sdk.NewDec(liquidStakedTokens))),
+		).
+		WithLiquidKeeper(
+			newFakeLiquidKeeper().addDerivative(suite.ctx, "bkava-asdf", sdk.NewInt(liquidStakedTokens)),
+		).
+		WithPricefeedKeeper(
+			newFakePricefeedKeeper().
+				setPrice(
+					pricefeedtypes.NewCurrentPrice(
+						"kava:usd:30",
+						sdk.MustNewDecFromStr("1.5"),
+					)),
+		).
+		Build()
+
+	// ~18% APR
+	expectedStakingAPY := inflation.
+		Mul(sdk.OneDec().Sub(communityTax)).
+		Quo(sdk.NewDec(bondedTokens).Quo(sdk.NewDec(totalSupply)))
+
+	// Staking APR = (Inflation Rate * (1 - Community Tax)) / (Bonded Tokens / Circulating Supply)
+	aprWithoutIncentives, err := keeper.GetStakingAPR(suite.ctx, suite.keeper, types.Params{})
+	suite.Require().NoError(err)
+	suite.Require().Equal(
+		expectedStakingAPY,
+		aprWithoutIncentives,
+	)
+
+	suite.T().Logf("Staking APR without incentives: %s", aprWithoutIncentives)
+
+	params := types.Params{
+		EarnRewardPeriods: types.MultiRewardPeriods{
+			{
+				Active:         true,
+				CollateralType: "bkava",
+				Start:          suite.ctx.BlockTime().Add(-time.Hour),
+				End:            suite.ctx.BlockTime().Add(time.Hour),
+				RewardsPerSecond: sdk.NewCoins(
+					sdk.NewCoin("ukava", sdk.NewInt(190258)),
+				),
+			},
+		},
+	}
+
+	aprWithIncentives, err := keeper.GetStakingAPR(suite.ctx, suite.keeper, params)
+	suite.Require().NoError(err)
+	// Approx 10% increase in APR from incentives
+	suite.Require().Equal(sdk.MustNewDecFromStr("0.280711113729177500"), aprWithIncentives)
+
+	suite.Require().Truef(
+		aprWithIncentives.GT(aprWithoutIncentives),
+		"APR with incentives (%s) should be greater than APR without incentives (%s)",
+	)
+}

x/incentive/keeper/unit_test.go

@@ -8,8 +8,10 @@ import (
 	"github.com/cosmos/cosmos-sdk/codec"
 	"github.com/cosmos/cosmos-sdk/store"
 	sdk "github.com/cosmos/cosmos-sdk/types"
+	minttypes "github.com/cosmos/cosmos-sdk/x/mint/types"
 	paramtypes "github.com/cosmos/cosmos-sdk/x/params/types"
 	stakingtypes "github.com/cosmos/cosmos-sdk/x/staking/types"
+	pricefeedtypes "github.com/kava-labs/kava/x/pricefeed/types"
 	"github.com/stretchr/testify/suite"
 	"github.com/tendermint/tendermint/libs/log"
 	db "github.com/tendermint/tm-db"
@@ -74,7 +76,11 @@ func (suite *unitTester) NewKeeper(
 	ak types.AccountKeeper, stk types.StakingKeeper, swk types.SwapKeeper,
 	svk types.SavingsKeeper, lqk types.LiquidKeeper, ek types.EarnKeeper,
 ) keeper.Keeper {
-	return keeper.NewKeeper(suite.cdc, suite.incentiveStoreKey, paramSubspace, bk, cdpk, hk, ak, stk, swk, svk, lqk, ek)
+	return keeper.NewKeeper(
+		suite.cdc, suite.incentiveStoreKey, paramSubspace,
+		bk, cdpk, hk, ak, stk, swk, svk, lqk, ek,
+		nil, nil, nil,
+	)
 }
 
 func (suite *unitTester) storeGlobalBorrowIndexes(indexes types.MultiRewardIndexes) {
@@ -133,6 +139,96 @@ func (suite *unitTester) storeEarnClaim(claim types.EarnClaim) {
 	suite.keeper.SetEarnClaim(suite.ctx, claim)
 }
 
+type TestKeeperBuilder struct {
+	cdc           codec.Codec
+	key           sdk.StoreKey
+	paramSubspace types.ParamSubspace
+	accountKeeper types.AccountKeeper
+	bankKeeper    types.BankKeeper
+	cdpKeeper     types.CdpKeeper
+	hardKeeper    types.HardKeeper
+	stakingKeeper types.StakingKeeper
+	swapKeeper    types.SwapKeeper
+	savingsKeeper types.SavingsKeeper
+	liquidKeeper  types.LiquidKeeper
+	earnKeeper    types.EarnKeeper
+
+	// Keepers used for APY queries
+	mintKeeper      types.MintKeeper
+	distrKeeper     types.DistrKeeper
+	pricefeedKeeper types.PricefeedKeeper
+}
+
+func (suite *unitTester) NewTestKeeper(
+	paramSubspace types.ParamSubspace,
+) *TestKeeperBuilder {
+	if !paramSubspace.HasKeyTable() {
+		paramSubspace = paramSubspace.WithKeyTable(types.ParamKeyTable())
+	}
+
+	return &TestKeeperBuilder{
+		cdc:             suite.cdc,
+		key:             suite.incentiveStoreKey,
+		paramSubspace:   paramSubspace,
+		accountKeeper:   nil,
+		bankKeeper:      nil,
+		cdpKeeper:       nil,
+		hardKeeper:      nil,
+		stakingKeeper:   nil,
+		swapKeeper:      nil,
+		savingsKeeper:   nil,
+		liquidKeeper:    nil,
+		earnKeeper:      nil,
+		mintKeeper:      nil,
+		distrKeeper:     nil,
+		pricefeedKeeper: nil,
+	}
+}
+
+func (tk *TestKeeperBuilder) WithPricefeedKeeper(k types.PricefeedKeeper) *TestKeeperBuilder {
+	tk.pricefeedKeeper = k
+	return tk
+}
+
+func (tk *TestKeeperBuilder) WithDistrKeeper(k types.DistrKeeper) *TestKeeperBuilder {
+	tk.distrKeeper = k
+	return tk
+}
+
+func (tk *TestKeeperBuilder) WithBankKeeper(k types.BankKeeper) *TestKeeperBuilder {
+	tk.bankKeeper = k
+	return tk
+}
+
+func (tk *TestKeeperBuilder) WithStakingKeeper(k types.StakingKeeper) *TestKeeperBuilder {
+	tk.stakingKeeper = k
+	return tk
+}
+
+func (tk *TestKeeperBuilder) WithMintKeeper(k types.MintKeeper) *TestKeeperBuilder {
+	tk.mintKeeper = k
+	return tk
+}
+
+func (tk *TestKeeperBuilder) WithEarnKeeper(k types.EarnKeeper) *TestKeeperBuilder {
+	tk.earnKeeper = k
+	return tk
+}
+
+func (tk *TestKeeperBuilder) WithLiquidKeeper(k types.LiquidKeeper) *TestKeeperBuilder {
+	tk.liquidKeeper = k
+	return tk
+}
+
+func (tk *TestKeeperBuilder) Build() keeper.Keeper {
+	return keeper.NewKeeper(
+		tk.cdc, tk.key, tk.paramSubspace,
+		tk.bankKeeper, tk.cdpKeeper, tk.hardKeeper, tk.accountKeeper,
+		tk.stakingKeeper, tk.swapKeeper, tk.savingsKeeper, tk.liquidKeeper,
+		tk.earnKeeper, tk.mintKeeper, tk.distrKeeper, tk.pricefeedKeeper,
+	)
+}
+
 // fakeParamSubspace is a stub paramSpace to simplify keeper unit test setup.
 type fakeParamSubspace struct {
 	params types.Params
@@ -410,6 +506,15 @@ func (k *fakeEarnKeeper) GetVaultTotalShares(
 	return vaultShares, found
 }
 
+func (k *fakeEarnKeeper) GetVaultTotalValue(ctx sdk.Context, denom string) (sdk.Coin, error) {
+	vaultShares, found := k.vaultShares[denom]
+	if !found {
+		return sdk.NewCoin(denom, sdk.ZeroInt()), nil
+	}
+
+	return sdk.NewCoin(denom, vaultShares.Amount.RoundInt()), nil
+}
+
 func (k *fakeEarnKeeper) GetVaultAccountShares(
 	ctx sdk.Context,
 	acc sdk.AccAddress,
@@ -519,6 +624,112 @@ func (k *fakeLiquidKeeper) getRewardAmount(
 	return amt.QuoRaw(10).MulRaw(duration)
 }
 
+type fakeDistrKeeper struct {
+	communityTax sdk.Dec
+}
+
+var _ types.DistrKeeper = newFakeDistrKeeper()
+
+func newFakeDistrKeeper() *fakeDistrKeeper {
+	return &fakeDistrKeeper{}
+}
+
+func (k *fakeDistrKeeper) setCommunityTax(percent sdk.Dec) *fakeDistrKeeper {
+	k.communityTax = percent
+	return k
+}
+
+func (k *fakeDistrKeeper) GetCommunityTax(ctx sdk.Context) (percent sdk.Dec) {
+	return k.communityTax
+}
+
+type fakeMintKeeper struct {
+	minter minttypes.Minter
+}
+
+var _ types.MintKeeper = newFakeMintKeeper()
+
+func newFakeMintKeeper() *fakeMintKeeper {
+	return &fakeMintKeeper{}
+}
+
+func (k *fakeMintKeeper) setMinter(minter minttypes.Minter) *fakeMintKeeper {
+	k.minter = minter
+	return k
+}
+
+func (k *fakeMintKeeper) GetMinter(ctx sdk.Context) (minter minttypes.Minter) {
+	return k.minter
+}
+
+type fakePricefeedKeeper struct {
+	prices map[string]pricefeedtypes.CurrentPrice
+}
+
+var _ types.PricefeedKeeper = newFakePricefeedKeeper()
+
+func newFakePricefeedKeeper() *fakePricefeedKeeper {
+	return &fakePricefeedKeeper{
+		prices: map[string]pricefeedtypes.CurrentPrice{},
+	}
+}
+
+func (k *fakePricefeedKeeper) setPrice(price pricefeedtypes.CurrentPrice) *fakePricefeedKeeper {
+	k.prices[price.MarketID] = price
+	return k
+}
+
+func (k *fakePricefeedKeeper) GetCurrentPrice(ctx sdk.Context, marketID string) (pricefeedtypes.CurrentPrice, error) {
+	price, found := k.prices[marketID]
+	if !found {
+		return pricefeedtypes.CurrentPrice{}, fmt.Errorf("price not found for market %s", marketID)
+	}
+
+	return price, nil
+}
+
+type fakeBankKeeper struct {
+	supply map[string]sdk.Int
+}
+
+var _ types.BankKeeper = newFakeBankKeeper()
+
+func newFakeBankKeeper() *fakeBankKeeper {
+	return &fakeBankKeeper{
+		supply: map[string]sdk.Int{},
+	}
+}
+
+func (k *fakeBankKeeper) setSupply(coins ...sdk.Coin) *fakeBankKeeper {
+	for _, coin := range coins {
+		k.supply[coin.Denom] = coin.Amount
+	}
+
+	return k
+}
+
+func (k *fakeBankKeeper) SendCoinsFromModuleToAccount(
+	ctx sdk.Context,
+	senderModule string,
+	recipientAddr sdk.AccAddress,
+	amt sdk.Coins,
+) error {
+	panic("not implemented")
+}
+
+func (k *fakeBankKeeper) GetAllBalances(ctx sdk.Context, addr sdk.AccAddress) sdk.Coins {
+	panic("not implemented")
+}
+
+func (k *fakeBankKeeper) GetSupply(ctx sdk.Context, denom string) sdk.Coin {
+	supply, found := k.supply[denom]
+	if !found {
+		return sdk.NewCoin(denom, sdk.ZeroInt())
+	}
+
+	return sdk.NewCoin(denom, supply)
+}
+
 // Assorted Testing Data
 
 // note: amino panics when encoding times ≥ the start of year 10000.

x/incentive/types/expected_keepers.go

@@ -3,11 +3,13 @@ package types
 import (
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
+	minttypes "github.com/cosmos/cosmos-sdk/x/mint/types"
 	paramtypes "github.com/cosmos/cosmos-sdk/x/params/types"
 	stakingtypes "github.com/cosmos/cosmos-sdk/x/staking/types"
 	cdptypes "github.com/kava-labs/kava/x/cdp/types"
 	earntypes "github.com/kava-labs/kava/x/earn/types"
 	hardtypes "github.com/kava-labs/kava/x/hard/types"
+	pricefeedtypes "github.com/kava-labs/kava/x/pricefeed/types"
 	savingstypes "github.com/kava-labs/kava/x/savings/types"
 )
 
@@ -23,6 +25,7 @@ type ParamSubspace interface {
 type BankKeeper interface {
 	SendCoinsFromModuleToAccount(ctx sdk.Context, senderModule string, recipientAddr sdk.AccAddress, amt sdk.Coins) error
 	GetAllBalances(ctx sdk.Context, addr sdk.AccAddress) sdk.Coins
+	GetSupply(ctx sdk.Context, denom string) sdk.Coin
 }
 
 // StakingKeeper defines the expected staking keeper for module accounts
@@ -67,6 +70,7 @@ type SavingsKeeper interface {
 // EarnKeeper defines the required methods needed by this modules keeper
 type EarnKeeper interface {
 	GetVaultTotalShares(ctx sdk.Context, denom string) (shares earntypes.VaultShare, found bool)
+	GetVaultTotalValue(ctx sdk.Context, denom string) (sdk.Coin, error)
 	GetVaultAccountShares(ctx sdk.Context, acc sdk.AccAddress) (shares earntypes.VaultShares, found bool)
 	IterateVaultRecords(ctx sdk.Context, cb func(record earntypes.VaultRecord) (stop bool))
 }
@@ -90,6 +94,21 @@ type AccountKeeper interface {
 	GetModuleAccount(ctx sdk.Context, name string) authtypes.ModuleAccountI
 }
 
+// MintKeeper defines the required methods needed by this modules keeper
+type MintKeeper interface {
+	GetMinter(ctx sdk.Context) (minter minttypes.Minter)
+}
+
+// DistrKeeper defines the required methods needed by this modules keeper
+type DistrKeeper interface {
+	GetCommunityTax(ctx sdk.Context) (percent sdk.Dec)
+}
+
+// PricefeedKeeper defines the required methods needed by this modules keeper
+type PricefeedKeeper interface {
+	GetCurrentPrice(ctx sdk.Context, marketID string) (pricefeedtypes.CurrentPrice, error)
+}
+
 // CDPHooks event hooks for other keepers to run code in response to CDP modifications
 type CDPHooks interface {
 	AfterCDPCreated(ctx sdk.Context, cdp cdptypes.CDP)

x/incentive/types/querier.go

@@ -14,6 +14,7 @@ const (
 	QueryGetEarnRewards        = "earn-rewards"
 	QueryGetRewardFactors      = "reward-factors"
 	QueryGetParams             = "parameters"
+	QueryGetAPYs               = "apys"
 
 	RestClaimCollateralType = "collateral_type"
 	RestClaimOwner          = "owner"
@@ -64,3 +65,32 @@ func NewQueryGetRewardFactorsResponse(usdxMintingFactors RewardIndexes, supplyFa
 		EarnRewardFactors:        earnFactors,
 	}
 }
+
+// APY contains the APY for a given collateral type
+type APY struct {
+	CollateralType string  `json:"collateral_type" yaml:"collateral_type"`
+	APY            sdk.Dec `json:"apy" yaml:"apy"`
+}
+
+// NewAPY returns a new instance of APY
+func NewAPY(collateralType string, apy sdk.Dec) APY {
+	return APY{
+		CollateralType: collateralType,
+		APY:            apy,
+	}
+}
+
+// APYs is a slice of APY
+type APYs []APY
+
+// QueryGetAPYsResponse holds the response to a APY query
+type QueryGetAPYsResponse struct {
+	Earn []APY `json:"earn" yaml:"earn"`
+}
+
+// NewQueryGetAPYsResponse returns a new instance of QueryGetAPYsResponse
+func NewQueryGetAPYsResponse(earn []APY) QueryGetAPYsResponse {
+	return QueryGetAPYsResponse{
+		Earn: earn,
+	}
+}