Ln/update quote currency endpoint for deso (#694)

* update quote currency price in usd endpoint to use dex for price of deso

* deprecate fields and fill deprecated fields with deso dex price

* if most recent dex price is 0, return gate price

* add const for dusdc profile username

routes/base.go

@@ -76,7 +76,7 @@ type GetExchangeRateResponse struct {
 	USDCentsPerDeSoReserveExchangeRate uint64
 	BuyDeSoFeeBasisPoints              uint64
 	USDCentsPerDeSoBlockchainDotCom    uint64
-	USDCentsPerDeSoCoinbase            uint64
+	USDCentsPerDeSoCoinbase            uint64 // Deprecated
 
 	SatoshisPerBitCloutExchangeRate        uint64 // Deprecated
 	USDCentsPerBitCloutExchangeRate        uint64 // Deprecated
@@ -131,11 +131,10 @@ func (fes *APIServer) GetExchangeRate(ww http.ResponseWriter, rr *http.Request)
 
 func (fes *APIServer) GetExchangeDeSoPrice() uint64 {
 	// We no longer observe a reserve rate.
+	if fes.MostRecentDesoDexPriceUSDCents == 0 {
+		return fes.MostRecentGatePriceUSDCents
+	}
 	return fes.MostRecentDesoDexPriceUSDCents
-	//if fes.UsdCentsPerDeSoExchangeRate > fes.USDCentsToDESOReserveExchangeRate {
-	//	return fes.UsdCentsPerDeSoExchangeRate
-	//}
-	//return fes.USDCentsToDESOReserveExchangeRate
 }
 
 type BlockchainDeSoTickerResponse struct {
@@ -340,7 +339,7 @@ func (fes *APIServer) GetExchangeRateFromDeSoDex() (float64, error) {
 	if err != nil {
 		return 0, err
 	}
-	usdcProfileEntry := utxoView.GetProfileEntryForUsername([]byte("dusdc_"))
+	usdcProfileEntry := utxoView.GetProfileEntryForUsername([]byte(dusdcProfileUsername))
 	if usdcProfileEntry == nil {
 		return 0, fmt.Errorf("GetExchangeRateFromDeSoDex: Could not find profile entry for dusdc_")
 	}
@@ -385,22 +384,16 @@ func (fes *APIServer) UpdateUSDCentsToDeSoExchangeRate() {
 		glog.Errorf("UpdateUSDCentsToDeSoExchangeRate: Error fetching exchange rate from DeSoDex: %v", err)
 	}
 
-	// Take the max
-	lastTradePrice, err := stats.Max([]float64{blockchainDotComPrice, gatePrice, desoDexPrice})
-
 	// store the most recent exchange prices
-	// For now, we are using gate.io as the primary exchange
-	// for pricing of deso.
-	//fes.MostRecentCoinbasePriceUSDCents = uint64(coinbasePrice)
-	fes.MostRecentCoinbasePriceUSDCents = uint64(gatePrice)
+	fes.MostRecentCoinbasePriceUSDCents = uint64(desoDexPrice)
 	fes.MostRecentBlockchainDotComPriceUSDCents = uint64(blockchainDotComPrice)
 	fes.MostRecentGatePriceUSDCents = uint64(gatePrice)
 	fes.MostRecentDesoDexPriceUSDCents = uint64(desoDexPrice)
 
 	// Get the current timestamp and append the current last trade price to the LastTradeDeSoPriceHistory slice
 	timestamp := uint64(time.Now().UnixNano())
 	fes.LastTradeDeSoPriceHistory = append(fes.LastTradeDeSoPriceHistory, LastTradePriceHistoryItem{
-		LastTradePrice: uint64(lastTradePrice),
+		LastTradePrice: uint64(desoDexPrice),
 		Timestamp:      timestamp,
 	})
 

routes/dao_coin_exchange_with_fees.go

@@ -16,6 +16,10 @@ import (
 	"strings"
 )
 
+const (
+	dusdcProfileUsername = "dusdc_"
+)
+
 type UpdateDaoCoinMarketFeesRequest struct {
 	// The profile that the fees are being modified for.
 	ProfilePublicKeyBase58Check string `safeForLogging:"true"`
@@ -908,22 +912,31 @@ const FOCUS_FLOOR_PRICE_DESO_NANOS = 166666
 
 func (fes *APIServer) GetQuoteCurrencyPriceInUsd(
 	quoteCurrencyPublicKey string) (_midmarket string, _bid string, _ask string, _err error) {
-	if IsDesoPkid(quoteCurrencyPublicKey) {
-		// TODO: We're taking the Coinbase price directly here, but ideally we would get it from
-		// a function that abstracts away the exchange we're getting it from. We do this for now
-		// in order to minimize discrepancies with other sources.
-		desoUsdCents := fes.MostRecentCoinbasePriceUSDCents
-		if desoUsdCents == 0 {
-			return "", "", "", fmt.Errorf("GetQuoteCurrencyPriceInUsd: Coinbase DESO price is zero")
-		}
-		price := fmt.Sprintf("%0.9f", float64(desoUsdCents)/100)
-		return price, price, price, nil // TODO: get real bid and ask prices.
-	}
 	utxoView, err := fes.backendServer.GetMempool().GetAugmentedUniversalView()
 	if err != nil {
 		return "", "", "", fmt.Errorf(
 			"GetQuoteCurrencyPriceInUsd: Error fetching mempool view: %v", err)
 	}
+	if IsDesoPkid(quoteCurrencyPublicKey) {
+		usdcProfileEntry := utxoView.GetProfileEntryForUsername([]byte(dusdcProfileUsername))
+		if usdcProfileEntry == nil {
+			return "", "", "", fmt.Errorf("GetQuoteCurrencyPriceInUsd: Could not find profile entry for dusdc_")
+		}
+
+		usdcPKID := utxoView.GetPKIDForPublicKey(usdcProfileEntry.PublicKey)
+		midMarketPrice, highestBidPrice, lowestAskPrice, err := fes.GetHighestBidAndLowestAskPriceFromPKIDs(
+			&lib.ZeroPKID, usdcPKID.PKID, utxoView, 0)
+		if err != nil {
+			return "", "", "", fmt.Errorf("GetQuoteCurrencyPriceInUsd: Error getting price for DESO: %v", err)
+		}
+		if highestBidPrice == 0.0 || lowestAskPrice == math.MaxFloat64 {
+			return "", "", "", fmt.Errorf("GetQuoteCurrencyPriceInUsd: Error calculating price for DESO")
+		}
+		return fmt.Sprintf("%0.9f", midMarketPrice),
+			fmt.Sprintf("%0.9f", highestBidPrice),
+			fmt.Sprintf("%0.9f", lowestAskPrice),
+			nil
+	}
 
 	pkBytes, _, err := lib.Base58CheckDecode(quoteCurrencyPublicKey)
 	if err != nil || len(pkBytes) != btcec.PubKeyBytesLenCompressed {
@@ -942,15 +955,14 @@ func (fes *APIServer) GetQuoteCurrencyPriceInUsd(
 
 	// If the profile is the dusdc profile then just return 1.0
 	lowerUsername := strings.ToLower(string(existingProfileEntry.Username))
-	if lowerUsername == "dusdc_" {
+	if lowerUsername == dusdcProfileUsername {
 		return "1.0", "1.0", "1.0", nil
 	} else if lowerUsername == "focus" ||
 		lowerUsername == "openfund" {
 
-		// TODO: We're taking the Coinbase price directly here, but ideally we would get it from
-		// a function that abstracts away the exchange we're getting it from. We do this for now
-		// in order to minimize discrepancies with other sources.
-		desoUsdCents := fes.MostRecentCoinbasePriceUSDCents
+		// Get the exchange deso price. currently this function
+		// just returns the price from the deso dex.
+		desoUsdCents := fes.GetExchangeDeSoPrice()
 		if desoUsdCents == 0 {
 			return "", "", "", fmt.Errorf("GetQuoteCurrencyPriceInUsd: Coinbase DESO price is zero")
 		}

routes/server.go

@@ -398,7 +398,7 @@ type APIServer struct {
 	LastTradePriceLookback uint64
 
 	// most recent exchange prices fetched
-	MostRecentCoinbasePriceUSDCents         uint64
+	MostRecentCoinbasePriceUSDCents         uint64 // Deprecated
 	MostRecentBlockchainDotComPriceUSDCents uint64
 	MostRecentGatePriceUSDCents             uint64
 	MostRecentDesoDexPriceUSDCents          uint64

routes/transaction.go

@@ -1199,7 +1199,7 @@ func (fes *APIServer) GetNanosFromUSDCents(usdCents float64, feeBasisPoints uint
 }
 
 func (fes *APIServer) GetUSDFromNanos(nanos uint64) float64 {
-	usdCentsPerDeSo := float64(fes.UsdCentsPerDeSoExchangeRate)
+	usdCentsPerDeSo := float64(fes.GetExchangeDeSoPrice())
 	return usdCentsPerDeSo * float64(nanos/lib.NanosPerUnit) / 100
 }