feat: translate currency

app/app.go

@@ -3,6 +3,8 @@ package app
 import (
 	"context"
 	"errors"
+	"net/http"
+
 	"github.com/danilsolovyov/croupierCbrf/dal"
 	"github.com/danilsolovyov/croupierCbrf/handlers"
 	"github.com/danilsolovyov/croupierCbrf/worker"
@@ -10,7 +12,6 @@ import (
 	"github.com/skeris/appInit"
 	"github.com/themakers/hlog"
 	"go.uber.org/zap"
-	"net/http"
 
 	//"net/http"
 	"os"
@@ -156,6 +157,7 @@ func New(ctx context.Context, options interface{}) (appInit.CommonApp, error) {
 	handler := handlers.NewHandler(connMongo, hlogger, "")
 
 	router.HandleFunc("/getQuotes", handler.GetQuotes)
+	router.HandleFunc("/change", handler.Translate)
 
 	// Startup server
 	srv := &http.Server{Addr: opts.AppAddr, Handler: router}

dal/quote.go

@@ -4,10 +4,11 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"time"
+
 	"go.mongodb.org/mongo-driver/bson"
 	"go.mongodb.org/mongo-driver/mongo"
 	"go.mongodb.org/mongo-driver/mongo/options"
-	"time"
 )
 
 type Quote struct {
@@ -21,6 +22,10 @@ type Quote struct {
 	UpdatedAt time.Time `bson:"UpdatedAt" json:"updated-at"`
 }
 
+const (
+	DefaultCurrency = "RUB"
+)
+
 // UpdateQuote with upsert option
 func (mc *MongoConnection) UpdateQuote(ctx context.Context, record *Quote) error {
 	filter := bson.M{"_id": record.ID}

go.mod

@@ -1,12 +1,31 @@
 module github.com/danilsolovyov/croupierCbrf
 
-go 1.16
+go 1.18
 
 require (
-	github.com/gorilla/mux v1.8.0 // indirect
+	github.com/gorilla/mux v1.8.0
 	github.com/skeris/appInit v0.1.12
+	github.com/stretchr/testify v1.7.0
 	github.com/themakers/hlog v0.0.0-20191205140925-235e0e4baddf
 	go.mongodb.org/mongo-driver v1.8.3
 	go.uber.org/zap v1.21.0
 	golang.org/x/text v0.3.7
 )
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/go-stack/stack v1.8.0 // indirect
+	github.com/golang/snappy v0.0.1 // indirect
+	github.com/klauspost/compress v1.13.6 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/xdg-go/pbkdf2 v1.0.0 // indirect
+	github.com/xdg-go/scram v1.0.2 // indirect
+	github.com/xdg-go/stringprep v1.0.2 // indirect
+	github.com/youmark/pkcs8 v0.0.0-20181117223130-1be2e3e5546d // indirect
+	go.uber.org/atomic v1.7.0 // indirect
+	go.uber.org/multierr v1.6.0 // indirect
+	golang.org/x/crypto v0.0.0-20201216223049-8b5274cf687f // indirect
+	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c // indirect
+	gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b // indirect
+)

go.sum

@@ -16,8 +16,10 @@ github.com/gorilla/mux v1.8.0/go.mod h1:DVbg23sWSpFRCP0SfiEN6jmj59UnW/n46BH5rLB7
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/klauspost/compress v1.13.6 h1:P76CopJELS0TiO2mebmnzgWaajssP/EszplttgQxcgc=
 github.com/klauspost/compress v1.13.6/go.mod h1:/3/Vjq9QcHkK5uEr5lBEmyoZ1iFhe47etQ6QUkpK6sk=
+github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/montanaflynn/stats v0.0.0-20171201202039-1bf9dbcd8cbe/go.mod h1:wL8QJuTMNUDYhXwkmfOly8iTdp5TEcJFWZD2D7SIkUc=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
@@ -104,6 +106,7 @@ golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8T
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

handlers/quote.go

@@ -2,11 +2,14 @@ package handlers
 
 import (
 	"net/http"
+	"strconv"
+
+	"github.com/danilsolovyov/croupierCbrf/dal"
+	"github.com/danilsolovyov/croupierCbrf/utils"
 )
 
 func (h *Handler) GetQuotes(w http.ResponseWriter, r *http.Request) {
 	result, err := h.mongo.GetQuoteList(r.Context())
-
 	if err != nil {
 		h.reportError(w, r, http.StatusInternalServerError, err.Error(), err)
 		return
@@ -17,3 +20,46 @@ func (h *Handler) GetQuotes(w http.ResponseWriter, r *http.Request) {
 		Message: result,
 	})
 }
+
+func (h *Handler) Translate(response http.ResponseWriter, request *http.Request) {
+	params := request.URL.Query()
+
+	currencyFrom := params.Get("currencyFrom")
+	currencyTo := params.Get("currencyTo")
+	value := params.Get("value")
+
+	if currencyFrom == "" {
+		currencyFrom = dal.DefaultCurrency
+	}
+
+	if currencyTo == "" {
+		currencyTo = dal.DefaultCurrency
+	}
+
+	parsedValue, err := strconv.ParseInt(value, 10, 64)
+	if err != nil {
+		h.reportError(response, request, http.StatusBadRequest, "invalid value format", err)
+
+		return
+	}
+
+	quotes, err := h.mongo.GetQuoteList(request.Context())
+	if err != nil {
+		h.reportError(response, request, http.StatusInternalServerError, err.Error(), err)
+		return
+	}
+
+	quotesMap := utils.ArrayToMap(quotes, func(quote dal.Quote) string {
+		return quote.ID
+	})
+
+	result, err := utils.CurrencyExchange(quotesMap, currencyFrom, currencyTo, parsedValue)
+	if err != nil {
+		h.reportError(response, request, http.StatusInternalServerError, err.Error(), err)
+	}
+
+	h.sendResponse(response, request, Response{
+		Success: true,
+		Message: result,
+	})
+}

openapi.yaml

@@ -14,11 +14,15 @@ paths:
         - currencies
       description: Получить количество денег в пересчёте на десятые части указанной валюты. На вход подаются копейки.
       parameters:
-        - name: cur
+        - name: currencyFrom
           in: query
-          description: валюта, в которую надо перевести переданнео число
+          description: валюта, из которой надо перевести переданное число
           required: true
-        - name: val
+        - name: currencyTo
+          in: query
+          description: валюта, в которую надо перевести переданное число
+          required: true
+        - name: value
           in: query
           description: количество копеек, которые надо перевести в указанную валюту
           required: true
@@ -32,4 +36,5 @@ paths:
                 properties:
                   money:
                     type: integer
+                    format: int64
                     example: 12065

utils/array_to_map.go

@@ -0,0 +1,11 @@
+package utils
+
+func ArrayToMap[T any, V comparable](array []T, key func(T) V) map[V]T {
+	result := make(map[V]T, len(array))
+
+	for _, element := range array {
+		result[key(element)] = element
+	}
+
+	return result
+}

utils/array_to_map_test.go

@@ -0,0 +1,69 @@
+package utils_test
+
+import (
+	"testing"
+
+	"github.com/danilsolovyov/croupierCbrf/utils"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestArrayToMap(t *testing.T) {
+	type testModel struct {
+		ID string
+	}
+
+	t.Run("Успешная конвертация массива в map без коллизий", func(t *testing.T) {
+		assert.NotPanics(t, func() {
+			result := utils.ArrayToMap(
+				[]testModel{{ID: "test"}, {ID: "test2"}},
+				func(model testModel) string {
+					return model.ID
+				},
+			)
+
+			assert.Equal(t,
+				map[string]testModel{
+					"test":  {ID: "test"},
+					"test2": {ID: "test2"},
+				},
+				result,
+			)
+		})
+	})
+
+	t.Run("Успешная конвертация массива в map с коллизиями", func(t *testing.T) {
+		assert.NotPanics(t, func() {
+			result := utils.ArrayToMap(
+				[]testModel{{ID: "test"}, {ID: "test"}},
+				func(model testModel) string {
+					return model.ID
+				},
+			)
+
+			assert.Equal(t,
+				map[string]testModel{
+					"test": {ID: "test"},
+				},
+				result,
+			)
+		})
+	})
+
+	t.Run("Успешная конвертация массива в map с функцией, возаращающая пустую строку", func(t *testing.T) {
+		assert.NotPanics(t, func() {
+			result := utils.ArrayToMap(
+				[]testModel{{ID: "test"}, {ID: "test"}},
+				func(model testModel) string {
+					return ""
+				},
+			)
+
+			assert.Equal(t,
+				map[string]testModel{
+					"": {ID: "test"},
+				},
+				result,
+			)
+		})
+	})
+}

utils/currency_exchange.go

@@ -0,0 +1,38 @@
+package utils
+
+import (
+	"fmt"
+	"math"
+
+	"github.com/danilsolovyov/croupierCbrf/dal"
+)
+
+func CurrencyExchange(currencies map[string]dal.Quote, fromCurrency, toCurrency string, amount int64) (int64, error) {
+	fromRate, ok := currencies[fromCurrency]
+	if !ok && fromCurrency != dal.DefaultCurrency {
+		return 0, fmt.Errorf("Курс для валюты %s не найден", fromCurrency)
+	}
+	if fromCurrency == dal.DefaultCurrency {
+		fromRate.Value = 1
+	}
+
+	toRate, ok := currencies[toCurrency]
+	if !ok && toCurrency != dal.DefaultCurrency {
+		return 0, fmt.Errorf("Курс для валюты %s не найден", toCurrency)
+	}
+	if toCurrency == dal.DefaultCurrency {
+		toRate.Value = 1
+	}
+
+	// Округляем число курса 79.9093 => 79.91
+	roundedFromValue := math.Round(fromRate.Value*100) / 100
+	roundedToValue := math.Round(toRate.Value*100) / 100
+
+	// Переводим сумму из одной валюты в рубли
+	amountInRubles := float64(amount) * roundedFromValue
+
+	// Переводим рубли в нужную валюту и округляем до ближайшего целого числа
+	result := int64(amountInRubles / roundedToValue)
+
+	return result, nil
+}

utils/currency_exchange_test.go

@@ -0,0 +1,106 @@
+package utils_test
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/danilsolovyov/croupierCbrf/dal"
+	"github.com/danilsolovyov/croupierCbrf/utils"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCurrencyExchange(t *testing.T) {
+	currencies := map[string]dal.Quote{
+		"USD": {ID: "USD", Value: 79.9093},
+		"EUR": {ID: "EUR", Value: 86.2770},
+		"BYN": {ID: "BYN", Value: 27.3110},
+	}
+
+	testCases := []struct {
+		from     string
+		to       string
+		value    int64
+		expected int64
+		isError  bool
+	}{
+		{
+			from:     "USD",
+			to:       "RUB",
+			value:    10000,
+			expected: 799100,
+		},
+		{
+			from:     "RUB",
+			to:       "RUB",
+			value:    10000,
+			expected: 10000,
+		},
+		{
+			from:     "BYN",
+			to:       "RUB",
+			value:    10000,
+			expected: 273100,
+		},
+		{
+			from:     "EUR",
+			to:       "RUB",
+			value:    10000,
+			expected: 862800,
+		},
+		{
+			from:     "RUB",
+			to:       "USD",
+			value:    799100,
+			expected: 10000,
+		},
+		{
+			from:     "RUB",
+			to:       "BYN",
+			value:    273100,
+			expected: 10000,
+		},
+		{
+			from:     "RUB",
+			to:       "EUR",
+			value:    862800,
+			expected: 10000,
+		},
+		{
+			from:     "BYN",
+			to:       "EUR",
+			value:    10000,
+			expected: 3165,
+		},
+		{
+			from:     "BYNNN",
+			to:       "EURRR",
+			value:    19900,
+			expected: 0,
+			isError:  true,
+		},
+		{
+			from:     "BYN",
+			to:       "EURRR",
+			value:    19900,
+			expected: 0,
+			isError:  true,
+		},
+	}
+
+	for _, testCase := range testCases {
+		result, err := utils.CurrencyExchange(currencies, testCase.from, testCase.to, testCase.value)
+
+		if testCase.isError {
+			assert.Equal(t, testCase.expected, result)
+			assert.Error(t, err)
+			continue
+		}
+
+		assert.NoError(t, err)
+		assert.Equal(t,
+			testCase.expected,
+			result,
+			fmt.Sprintf("Неверный результат при переводе с %s на %s", testCase.from, testCase.to),
+		)
+	}
+}