pkg/exchange: use fixedpoint as value

pkg/exchange/binance/binanceapi/client_test.go

@@ -11,6 +11,7 @@ import (
 
 	"github.com/stretchr/testify/assert"
 
+	"github.com/c9s/bbgo/pkg/fixedpoint"
 	"github.com/c9s/bbgo/pkg/testutil"
 )
 
@@ -206,7 +207,7 @@ func TestClient_NewPlaceMarginOrderRequest(t *testing.T) {
 
 	res, err := client.NewPlaceMarginOrderRequest().
 		Asset("USDT").
-		Amount("5").
+		Amount(fixedpoint.NewFromFloat(5)).
 		IsIsolated(true).
 		Symbol("BNBUSDT").
 		SetBorrowRepayType(BorrowRepayTypeBorrow).
@@ -233,7 +234,7 @@ func TestClient_NewPlaceMarginOrderRequest(t *testing.T) {
 
 	res, err = client.NewPlaceMarginOrderRequest().
 		Asset("USDT").
-		Amount("5").
+		Amount(fixedpoint.NewFromFloat(5)).
 		IsIsolated(true).
 		Symbol("BNBUSDT").
 		SetBorrowRepayType(BorrowRepayTypeRepay).

pkg/exchange/binance/binanceapi/place_margin_order_request.go

@@ -2,6 +2,8 @@ package binanceapi
 
 import (
 	"github.com/c9s/requestgen"
+
+	"github.com/c9s/bbgo/pkg/fixedpoint"
 )
 
 //go:generate requestgen -method POST -url "/sapi/v1/margin/borrow-repay" -type PlaceMarginOrderRequest -responseType .TransferResponse
@@ -16,7 +18,7 @@ type PlaceMarginOrderRequest struct {
 	// Only for Isolated margin
 	symbol *string `param:"symbol"`
 
-	amount string `param:"amount"`
+	amount fixedpoint.Value `param:"amount"`
 
 	BorrowRepayType BorrowRepayType `param:"type"`
 }

pkg/exchange/binance/exchange.go

@@ -331,7 +331,7 @@ func (e *Exchange) QueryMarginAssetMaxBorrowable(ctx context.Context, asset stri
 func (e *Exchange) borrowRepayAsset(ctx context.Context, asset string, amount fixedpoint.Value, marginType binanceapi.BorrowRepayType) error {
 	req := e.client2.NewPlaceMarginOrderRequest()
 	req.Asset(asset)
-	req.Amount(amount.String())
+	req.Amount(amount)
 	req.SetBorrowRepayType(marginType)
 	if e.IsIsolatedMargin {
 		req.IsIsolated(e.IsIsolatedMargin)