comp v2 fees using rates

Author: noateden

fees/takara-lend/index.ts

@@ -3,4 +3,4 @@ import { compoundV2Export, } from "../../helpers/compoundV2";
 
 const unitroller = "0x71034bf5eC0FAd7aEE81a213403c8892F3d8CAeE";
 
-export default compoundV2Export({ sei: unitroller});
+export default compoundV2Export({ sei: unitroller}, true);

helpers/compoundV2.ts

@@ -8,6 +8,8 @@ const comptrollerABI = {
   getAllMarkets: "address[]:getAllMarkets",
   accrueInterest: "event AccrueInterest(uint256 cashPrior,uint256 interestAccumulated,uint256 borrowIndex,uint256 totalBorrows)",
   reserveFactor: "uint256:reserveFactorMantissa",
+  exchangeRateCurrent: "uint256:exchangeRateCurrent",
+  totalSupply: "uint256:totalSupply",
 };
 
 export async function getFees(market: string, { createBalances, api, getLogs, }: FetchOptions, {
@@ -49,6 +51,47 @@ export async function getFees(market: string, { createBalances, api, getLogs, }:
   return { dailyFees, dailyRevenue }
 }
 
+export async function getFeesUseExchangeRates(market: string, { createBalances, api, fromApi, toApi, }: FetchOptions, {
+  dailyFees,
+  dailyRevenue,
+  abis = {},
+}: {
+  dailyFees?: sdk.Balances,
+  dailyRevenue?: sdk.Balances,
+  abis?: any
+}) {
+  if (!dailyFees) dailyFees = createBalances()
+  if (!dailyRevenue) dailyRevenue = createBalances()
+  const markets = await api.call({ target: market, abi: comptrollerABI.getAllMarkets, })
+  const underlyings = await api.multiCall({ calls: markets, abi: comptrollerABI.underlying, permitFailure: true, });
+  underlyings.forEach((underlying, index) => {
+    if (!underlying) underlyings[index] = ADDRESSES.null
+  })
+  const reserveFactors = await api.multiCall({ calls: markets, abi: abis.reserveFactor ?? comptrollerABI.reserveFactor, });
+  
+  const marketExchangeRatesBefore = await fromApi.multiCall({ calls: markets, abi: comptrollerABI.exchangeRateCurrent, });
+  const marketExchangeRatesAfter = await toApi.multiCall({ calls: markets, abi: comptrollerABI.exchangeRateCurrent, });
+  const totalSupplies = await toApi.multiCall({ calls: markets, abi: comptrollerABI.totalSupply, });
+  const underlyingDecimals = await toApi.multiCall({ calls: underlyings, abi: 'uint8:decimals', });
+  
+  for (let i = 0; i < markets.length; i++) {
+    const underlying = underlyings[i];
+    const underlyingDecimal = Number(underlyingDecimals[i]);
+    const reserveFactor = reserveFactors[i];
+    const rateGrowth = Number(marketExchangeRatesAfter[i]) - Number(marketExchangeRatesBefore[i])
+    if (rateGrowth > 0) {
+      const mantissa = 18 + underlyingDecimal - 8
+      const interestAccumulated = rateGrowth * Number(totalSupplies[i]) * (10 ** underlyingDecimal) / (10 ** mantissa) / 1e8
+      const revenueAccumulated = interestAccumulated * reserveFactor / 1e18
+      
+      dailyFees!.add(underlying, interestAccumulated, METRIC.BORROW_INTEREST);
+      dailyRevenue!.add(underlying, revenueAccumulated, METRIC.BORROW_INTEREST);
+    }
+  }
+
+  return { dailyFees, dailyRevenue }
+}
+
 export function getFeesExport(market: string) {
   return (async (timestamp: number, _: any, options: FetchOptions) => {
     const { dailyFees, dailyRevenue } = await getFees(market, options, {})
@@ -62,12 +105,12 @@ export function getFeesExport(market: string) {
   }) as Fetch
 }
 
-export function compoundV2Export(config: IJSON<string>) {
+export function compoundV2Export(config: IJSON<string>, useExchangeRate?: boolean) {
   const exportObject: BaseAdapter = {}
   Object.entries(config).map(([chain, market]) => {
     exportObject[chain] = {
       fetch: (async (options: FetchOptions) => {
-        const { dailyFees, dailyRevenue } = await getFees(market, options, {})
+        const { dailyFees, dailyRevenue } = useExchangeRate ? await getFeesUseExchangeRates(market, options, {}) : await getFees(market, options, {})
         const dailyHoldersRevenue = dailyRevenue
         const dailySupplySideRevenue = options.createBalances()
         dailySupplySideRevenue.addBalances(dailyFees)