add balance sum to /addreses endpoint

api/v1/addresses/handler.go

@@ -30,6 +30,7 @@ type GetAddressRequestQuery struct {
 
 type GetAddressesRequest struct {
 	Addresses []string `form:"addresses[]" binding:"required,minterAddress,max=50"`
+	WithSum   bool     `form:"withSum"`
 }
 
 // TODO: replace string to int
@@ -77,6 +78,18 @@ func GetAddresses(c *gin.Context) {
 		}
 	}
 
+	// calculate overall address balance in base coin and fiat
+	if request.WithSum {
+		c.JSON(http.StatusOK, gin.H{
+			"data": resource.TransformCollectionWithCallback(addresses, address.Resource{}, func(model interface{}) resource.ParamsInterface {
+				baseCoin, usd := explorer.BalanceService.GetSumByAddress(model.(models.Address))
+				return resource.ParamsInterface{baseCoin, usd}
+			}),
+		})
+
+		return
+	}
+
 	c.JSON(http.StatusOK, gin.H{
 		"data": resource.TransformCollection(addresses, address.Resource{}),
 	})
@@ -102,18 +115,17 @@ func GetAddress(c *gin.Context) {
 	// fetch address
 	model := explorer.AddressRepository.GetByAddress(*minterAddress)
 
-	// calculate overall address balance in base coin and fiat
-	var balanceSumInBaseCoin, balanceSumInUSD *big.Float
-	if request.WithSum {
-		balanceSumInBaseCoin = explorer.BalanceService.GetBalanceSumByAddress(model)
-		balanceSumInUSD = explorer.BalanceService.GetBalanceSumInUSDByBaseCoin(balanceSumInBaseCoin)
-	}
-
 	// if no models found
 	if model == nil {
 		model = makeEmptyAddressModel(*minterAddress, explorer.Environment.BaseCoin)
 	}
 
+	// calculate overall address balance in base coin and fiat
+	var balanceSumInBaseCoin, balanceSumInUSD *big.Float
+	if request.WithSum {
+		balanceSumInBaseCoin, balanceSumInUSD = explorer.BalanceService.GetSumByAddress(*model)
+	}
+
 	c.JSON(http.StatusOK, gin.H{
 		"data": new(address.Resource).Transform(*model, balanceSumInBaseCoin, balanceSumInUSD),
 	})

balance/service.go

@@ -17,11 +17,7 @@ func NewService(baseCoin string, marketService *market.Service) *Service {
 	return &Service{baseCoin, marketService}
 }
 
-func (s *Service) GetBalanceSumByAddress(address *models.Address) *big.Float {
-	if address == nil {
-		return big.NewFloat(0)
-	}
-
+func (s *Service) GetSumByAddress(address models.Address) (*big.Float, *big.Float) {
 	sum := big.NewInt(0)
 	for _, balance := range address.Balances {
 		if balance.Coin.Symbol == s.baseCoin {
@@ -37,9 +33,10 @@ func (s *Service) GetBalanceSumByAddress(address *models.Address) *big.Float {
 		))
 	}
 
-	return new(big.Float).SetInt(sum)
+	sumInBaseCoin := new(big.Float).SetInt(sum)
+	return sumInBaseCoin, s.getBalanceSumInUSDByBaseCoin(sumInBaseCoin)
 }
 
-func (s *Service) GetBalanceSumInUSDByBaseCoin(sumInBasecoin *big.Float) *big.Float {
+func (s *Service) getBalanceSumInUSDByBaseCoin(sumInBasecoin *big.Float) *big.Float {
 	return new(big.Float).Mul(sumInBasecoin, big.NewFloat(s.marketService.PriceChange.Price))
 }

resource/main.go

@@ -6,11 +6,33 @@ import (
 
 type ItemInterface interface{}
 
+type ParamsInterface []interface{}
+
 type Interface interface {
 	Transform(model ItemInterface, params ...interface{}) Interface
 }
 
 func TransformCollection(collection interface{}, resource Interface) []Interface {
+	models := makeItemsFromModelsCollection(collection)
+	result := make([]Interface, len(models))
+	for i := range models {
+		result[i] = resource.Transform(models[i])
+	}
+
+	return result
+}
+
+func TransformCollectionWithCallback(collection interface{}, resource Interface, callbackFunc func(values interface{}) ParamsInterface) []Interface {
+	models := makeItemsFromModelsCollection(collection)
+	result := make([]Interface, len(models))
+	for i := range models {
+		result[i] = resource.Transform(models[i], callbackFunc(models[i])...)
+	}
+
+	return result
+}
+
+func makeItemsFromModelsCollection(collection interface{}) []ItemInterface {
 	val := reflect.ValueOf(collection)
 
 	models := make([]ItemInterface, val.Len())
@@ -22,10 +44,5 @@ func TransformCollection(collection interface{}, resource Interface) []Interface
 		}
 	}
 
-	result := make([]Interface, len(models))
-	for i := range models {
-		result[i] = resource.Transform(models[i])
-	}
-
-	return result
+	return models
 }