Cache currency conversion

cointop/conversion.go

@@ -309,11 +309,8 @@ func (ct *Cointop) Convert(convertFrom string, convertTo string, amount float64)
 	var rate float64
 	if convertFrom == convertTo {
 		rate = 1.0
-	} else if convertFrom == "usd" && convertTo == "aud" {
-		rate = 1.33 // TODO: cache exchange rates and remove this dodgy hack
-		log.Debugf("XXX DODGY HACK Convert(%s, %s, %f) = %f", convertFrom, convertTo, amount, rate*amount)
 	} else {
-		crate, err := ct.api.GetExchangeRate(convertFrom, convertTo)
+		crate, err := ct.api.GetExchangeRate(convertFrom, convertTo, true)
 		if err != nil {
 			return 0, err
 		}

cointop/table_header.go

@@ -236,7 +236,7 @@ func (ct *Cointop) UpdateTableHeader() error {
 		}
 		leftAlign := ct.GetTableColumnAlignLeft(col)
 		switch col {
-		case "price", "balance", "profit":
+		case "price", "balance", "profit", "cost":
 			label = fmt.Sprintf("%s%s", ct.CurrencySymbol(), label)
 		}
 		if leftAlign {

pkg/api/impl/coingecko/coingecko.go

@@ -12,6 +12,7 @@ import (
 	apitypes "github.com/cointop-sh/cointop/pkg/api/types"
 	"github.com/cointop-sh/cointop/pkg/api/util"
 	gecko "github.com/cointop-sh/cointop/pkg/api/vendors/coingecko/v3"
+	"github.com/cointop-sh/cointop/pkg/api/vendors/coingecko/v3/types"
 	geckoTypes "github.com/cointop-sh/cointop/pkg/api/vendors/coingecko/v3/types"
 )
 
@@ -33,6 +34,7 @@ type Service struct {
 	maxResultsPerPage uint
 	maxPages          uint
 	cacheMap          sync.Map
+	cachedRates       *types.ExchangeRatesItem
 }
 
 // NewCoinGecko new service
@@ -146,14 +148,26 @@ func (s *Service) GetCoinGraphData(convert, symbol, name string, start, end int6
 	return ret, nil
 }
 
+// GetCachedExchangeRates returns an indefinitely cached set of exchange rates
+func (s *Service) GetExchangeRates(cached bool) (*types.ExchangeRatesItem, error) {
+	if s.cachedRates == nil || !cached {
+		rates, err := s.client.ExchangeRates()
+		if err != nil {
+			return nil, err
+		}
+		s.cachedRates = rates
+	}
+	return s.cachedRates, nil
+}
+
 // GetExchangeRate gets the current excange rate between two currencies
-func (s *Service) GetExchangeRate(convertFrom string, convertTo string) (float64, error) {
+func (s *Service) GetExchangeRate(convertFrom string, convertTo string, cached bool) (float64, error) {
 	convertFrom = strings.ToLower(convertFrom)
 	convertTo = strings.ToLower(convertTo)
 	if convertFrom == convertTo {
 		return 1.0, nil
 	}
-	rates, err := s.client.ExchangeRates()
+	rates, err := s.GetExchangeRates(cached)
 	if err != nil {
 		return 0, err
 	}
@@ -188,7 +202,7 @@ func (s *Service) GetGlobalMarketGraphData(convert string, start int64, end int6
 
 	// This API does not appear to support vs_currency and only returns USD, so use ExchangeRates to convert
 	// TODO: watch out - this is not cached, so we hit the backend every time!
-	rate, err := s.GetExchangeRate("usd", convertTo)
+	rate, err := s.GetExchangeRate("usd", convertTo, true)
 	if err != nil {
 		return ret, err
 	}

pkg/api/impl/coinmarketcap/coinmarketcap.go

@@ -432,7 +432,7 @@ func getChartInterval(start, end int64) string {
 }
 
 // GetExchangeRate gets the current excange rate between two currencies
-func (s *Service) GetExchangeRate(convertFrom string, convertTo string) (float64, error) {
+func (s *Service) GetExchangeRate(convertFrom string, convertTo string, cached bool) (float64, error) {
 	if convertFrom == convertTo {
 		return 1.0, nil
 	}

pkg/api/interface.go

@@ -16,5 +16,5 @@ type Interface interface {
 	CoinLink(name string) string
 	SupportedCurrencies() []string
 	Price(name string, convert string) (float64, error)
-	GetExchangeRate(convertFrom string, convertTo string) (float64, error)
+	GetExchangeRate(convertFrom string, convertTo string, cached bool) (float64, error) // I don't love this caching
 }