add history to currency

currency/handler/currency.go

@@ -7,6 +7,8 @@ import (
 	"io/ioutil"
 	"net/http"
 	"time"
+	"regexp"
+	"strings"
 
 	"github.com/micro/micro/v3/service/errors"
 	"github.com/micro/micro/v3/service/logger"
@@ -14,6 +16,10 @@ import (
 	"github.com/patrickmn/go-cache"
 )
 
+var (
+	re = regexp.MustCompile(`\d{4}-\d{2}-\d{2}`)
+)
+
 type Currency struct {
 	Api   string
 	Cache *cache.Cache
@@ -67,6 +73,74 @@ func (c *Currency) Codes(ctx context.Context, req *pb.CodesRequest, rsp *pb.Code
 	return nil
 }
 
+func (c *Currency) History(ctx context.Context, req *pb.HistoryRequest, rsp *pb.HistoryResponse) error {
+	if len(req.Code) == 0 {
+		return errors.BadRequest("currency.rates", "missing code")
+	}
+	if len(req.Code) != 3 {
+		return errors.BadRequest("currency.rates", "code is invalid")
+	}
+
+	if len(req.Date) == 0 {
+		return errors.BadRequest("currency.history", "missing date")
+	}
+
+	if !re.MatchString(req.Date) {
+		return errors.BadRequest("currency.history", "invalid date")
+	}
+
+	// try the cache
+	if rates, ok := c.Cache.Get("history:" + req.Code+req.Date); ok {
+		rsp.Code = req.Code
+		rsp.Date = req.Date
+		rsp.Rates = rates.(map[string]float64)
+		return nil
+	}
+
+	parts := strings.Split(req.Date, "-")
+
+	resp, err := http.Get(fmt.Sprintf("%s/history/%s/%s/%s/%s", c.Api, req.Code, parts[0], parts[1], parts[2]))
+	if err != nil {
+		logger.Errorf("Failed to get historic rates: %v\n", err)
+		return errors.InternalServerError("currency.history", "failed to get history")
+	}
+	defer resp.Body.Close()
+
+	b, _ := ioutil.ReadAll(resp.Body)
+
+	if resp.StatusCode != 200 {
+		logger.Errorf("Failed to get historic rates (non 200): %d %v\n", resp.StatusCode, string(b))
+		return errors.InternalServerError("currency.history", "failed to get history")
+	}
+
+	var respBody map[string]interface{}
+
+	if err := json.Unmarshal(b, &respBody); err != nil {
+		logger.Errorf("Failed to unmarshal historic rates: %v\n", err)
+		return errors.InternalServerError("currency.history", "failed to get history")
+	}
+
+	rates, ok := respBody["conversion_rates"].(map[string]interface{})
+	if !ok {
+		logger.Errorf("Failed to convert historic rates to map[string]interface{}: %v\n", ok)
+		return errors.InternalServerError("currency.history", "failed to get history")
+	}
+
+	rsp.Code = req.Code
+	rsp.Date = req.Date
+	rsp.Rates = make(map[string]float64)
+
+	for code, rate := range rates {
+		rsp.Rates[code], _ = rate.(float64)
+	}
+
+	// set for a period of time
+	c.Cache.Set("history:"+req.Code+req.Date, rsp.Rates, time.Hour * 24)
+
+	return nil
+}
+
+
 func (c *Currency) Rates(ctx context.Context, req *pb.RatesRequest, rsp *pb.RatesResponse) error {
 	if len(req.Code) == 0 {
 		return errors.BadRequest("currency.rates", "missing code")

currency/proto/currency.pb.go

@@ -163,6 +163,130 @@ func (x *CodesResponse) GetCodes() []*Code {
 	return nil
 }
 
+// Returns the historic rates for a currency on a given date
+type HistoryRequest struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// currency code e.g USD
+	Code string `protobuf:"bytes,1,opt,name=code,proto3" json:"code,omitempty"`
+	// date formatted as YYYY-MM-DD
+	Date string `protobuf:"bytes,2,opt,name=date,proto3" json:"date,omitempty"`
+}
+
+func (x *HistoryRequest) Reset() {
+	*x = HistoryRequest{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_proto_currency_proto_msgTypes[3]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *HistoryRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*HistoryRequest) ProtoMessage() {}
+
+func (x *HistoryRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_proto_currency_proto_msgTypes[3]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use HistoryRequest.ProtoReflect.Descriptor instead.
+func (*HistoryRequest) Descriptor() ([]byte, []int) {
+	return file_proto_currency_proto_rawDescGZIP(), []int{3}
+}
+
+func (x *HistoryRequest) GetCode() string {
+	if x != nil {
+		return x.Code
+	}
+	return ""
+}
+
+func (x *HistoryRequest) GetDate() string {
+	if x != nil {
+		return x.Date
+	}
+	return ""
+}
+
+type HistoryResponse struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// The code of the request
+	Code string `protobuf:"bytes,1,opt,name=code,proto3" json:"code,omitempty"`
+	// The date requested
+	Date string `protobuf:"bytes,2,opt,name=date,proto3" json:"date,omitempty"`
+	// The rate for the day as code:rate
+	Rates map[string]float64 `protobuf:"bytes,3,rep,name=rates,proto3" json:"rates,omitempty" protobuf_key:"bytes,1,opt,name=key,proto3" protobuf_val:"fixed64,2,opt,name=value,proto3"`
+}
+
+func (x *HistoryResponse) Reset() {
+	*x = HistoryResponse{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_proto_currency_proto_msgTypes[4]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *HistoryResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*HistoryResponse) ProtoMessage() {}
+
+func (x *HistoryResponse) ProtoReflect() protoreflect.Message {
+	mi := &file_proto_currency_proto_msgTypes[4]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use HistoryResponse.ProtoReflect.Descriptor instead.
+func (*HistoryResponse) Descriptor() ([]byte, []int) {
+	return file_proto_currency_proto_rawDescGZIP(), []int{4}
+}
+
+func (x *HistoryResponse) GetCode() string {
+	if x != nil {
+		return x.Code
+	}
+	return ""
+}
+
+func (x *HistoryResponse) GetDate() string {
+	if x != nil {
+		return x.Date
+	}
+	return ""
+}
+
+func (x *HistoryResponse) GetRates() map[string]float64 {
+	if x != nil {
+		return x.Rates
+	}
+	return nil
+}
+
 // Rates returns the currency rates for a given code e.g USD
 type RatesRequest struct {
 	state         protoimpl.MessageState
@@ -176,7 +300,7 @@ type RatesRequest struct {
 func (x *RatesRequest) Reset() {
 	*x = RatesRequest{}
 	if protoimpl.UnsafeEnabled {
-		mi := &file_proto_currency_proto_msgTypes[3]
+		mi := &file_proto_currency_proto_msgTypes[5]
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		ms.StoreMessageInfo(mi)
 	}
@@ -189,7 +313,7 @@ func (x *RatesRequest) String() string {
 func (*RatesRequest) ProtoMessage() {}
 
 func (x *RatesRequest) ProtoReflect() protoreflect.Message {
-	mi := &file_proto_currency_proto_msgTypes[3]
+	mi := &file_proto_currency_proto_msgTypes[5]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -202,7 +326,7 @@ func (x *RatesRequest) ProtoReflect() protoreflect.Message {
 
 // Deprecated: Use RatesRequest.ProtoReflect.Descriptor instead.
 func (*RatesRequest) Descriptor() ([]byte, []int) {
-	return file_proto_currency_proto_rawDescGZIP(), []int{3}
+	return file_proto_currency_proto_rawDescGZIP(), []int{5}
 }
 
 func (x *RatesRequest) GetCode() string {
@@ -226,7 +350,7 @@ type RatesResponse struct {
 func (x *RatesResponse) Reset() {
 	*x = RatesResponse{}
 	if protoimpl.UnsafeEnabled {
-		mi := &file_proto_currency_proto_msgTypes[4]
+		mi := &file_proto_currency_proto_msgTypes[6]
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		ms.StoreMessageInfo(mi)
 	}
@@ -239,7 +363,7 @@ func (x *RatesResponse) String() string {
 func (*RatesResponse) ProtoMessage() {}
 
 func (x *RatesResponse) ProtoReflect() protoreflect.Message {
-	mi := &file_proto_currency_proto_msgTypes[4]
+	mi := &file_proto_currency_proto_msgTypes[6]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -252,7 +376,7 @@ func (x *RatesResponse) ProtoReflect() protoreflect.Message {
 
 // Deprecated: Use RatesResponse.ProtoReflect.Descriptor instead.
 func (*RatesResponse) Descriptor() ([]byte, []int) {
-	return file_proto_currency_proto_rawDescGZIP(), []int{4}
+	return file_proto_currency_proto_rawDescGZIP(), []int{6}
 }
 
 func (x *RatesResponse) GetCode() string {
@@ -286,7 +410,7 @@ type ConvertRequest struct {
 func (x *ConvertRequest) Reset() {
 	*x = ConvertRequest{}
 	if protoimpl.UnsafeEnabled {
-		mi := &file_proto_currency_proto_msgTypes[5]
+		mi := &file_proto_currency_proto_msgTypes[7]
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		ms.StoreMessageInfo(mi)
 	}
@@ -299,7 +423,7 @@ func (x *ConvertRequest) String() string {
 func (*ConvertRequest) ProtoMessage() {}
 
 func (x *ConvertRequest) ProtoReflect() protoreflect.Message {
-	mi := &file_proto_currency_proto_msgTypes[5]
+	mi := &file_proto_currency_proto_msgTypes[7]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -312,7 +436,7 @@ func (x *ConvertRequest) ProtoReflect() protoreflect.Message {
 
 // Deprecated: Use ConvertRequest.ProtoReflect.Descriptor instead.
 func (*ConvertRequest) Descriptor() ([]byte, []int) {
-	return file_proto_currency_proto_rawDescGZIP(), []int{5}
+	return file_proto_currency_proto_rawDescGZIP(), []int{7}
 }
 
 func (x *ConvertRequest) GetFrom() string {
@@ -354,7 +478,7 @@ type ConvertResponse struct {
 func (x *ConvertResponse) Reset() {
 	*x = ConvertResponse{}
 	if protoimpl.UnsafeEnabled {
-		mi := &file_proto_currency_proto_msgTypes[6]
+		mi := &file_proto_currency_proto_msgTypes[8]
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		ms.StoreMessageInfo(mi)
 	}
@@ -367,7 +491,7 @@ func (x *ConvertResponse) String() string {
 func (*ConvertResponse) ProtoMessage() {}
 
 func (x *ConvertResponse) ProtoReflect() protoreflect.Message {
-	mi := &file_proto_currency_proto_msgTypes[6]
+	mi := &file_proto_currency_proto_msgTypes[8]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -380,7 +504,7 @@ func (x *ConvertResponse) ProtoReflect() protoreflect.Message {
 
 // Deprecated: Use ConvertResponse.ProtoReflect.Descriptor instead.
 func (*ConvertResponse) Descriptor() ([]byte, []int) {
-	return file_proto_currency_proto_rawDescGZIP(), []int{6}
+	return file_proto_currency_proto_rawDescGZIP(), []int{8}
 }
 
 func (x *ConvertResponse) GetFrom() string {
@@ -424,44 +548,62 @@ var file_proto_currency_proto_rawDesc = []byte{
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+	0x65, 0x22, 0x00, 0x42, 0x12, 0x5a, 0x10, 0x2e, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x3b, 0x63,
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 }
 
 var (
@@ -476,31 +618,37 @@ func file_proto_currency_proto_rawDescGZIP() []byte {
 	return file_proto_currency_proto_rawDescData
 }
 
-var file_proto_currency_proto_msgTypes = make([]protoimpl.MessageInfo, 8)
+var file_proto_currency_proto_msgTypes = make([]protoimpl.MessageInfo, 11)
 var file_proto_currency_proto_goTypes = []interface{}{
 	(*Code)(nil),            // 0: currency.Code
 	(*CodesRequest)(nil),    // 1: currency.CodesRequest
 	(*CodesResponse)(nil),   // 2: currency.CodesResponse
-	(*RatesRequest)(nil),    // 3: currency.RatesRequest
+	(*HistoryRequest)(nil),  // 3: currency.HistoryRequest
-	(*RatesResponse)(nil),   // 4: currency.RatesResponse
+	(*HistoryResponse)(nil), // 4: currency.HistoryResponse
-	(*ConvertRequest)(nil),  // 5: currency.ConvertRequest
+	(*RatesRequest)(nil),    // 5: currency.RatesRequest
-	(*ConvertResponse)(nil), // 6: currency.ConvertResponse
+	(*RatesResponse)(nil),   // 6: currency.RatesResponse
-	nil,                     // 7: currency.RatesResponse.RatesEntry
+	(*ConvertRequest)(nil),  // 7: currency.ConvertRequest
+	(*ConvertResponse)(nil), // 8: currency.ConvertResponse
+	nil,                     // 9: currency.HistoryResponse.RatesEntry
+	nil,                     // 10: currency.RatesResponse.RatesEntry
 }
 var file_proto_currency_proto_depIdxs = []int32{
-	0, // 0: currency.CodesResponse.codes:type_name -> currency.Code
+	0,  // 0: currency.CodesResponse.codes:type_name -> currency.Code
-	7, // 1: currency.RatesResponse.rates:type_name -> currency.RatesResponse.RatesEntry
+	9,  // 1: currency.HistoryResponse.rates:type_name -> currency.HistoryResponse.RatesEntry
-	1, // 2: currency.Currency.Codes:input_type -> currency.CodesRequest
+	10, // 2: currency.RatesResponse.rates:type_name -> currency.RatesResponse.RatesEntry
-	3, // 3: currency.Currency.Rates:input_type -> currency.RatesRequest
+	1,  // 3: currency.Currency.Codes:input_type -> currency.CodesRequest
-	5, // 4: currency.Currency.Convert:input_type -> currency.ConvertRequest
+	5,  // 4: currency.Currency.Rates:input_type -> currency.RatesRequest
-	2, // 5: currency.Currency.Codes:output_type -> currency.CodesResponse
+	7,  // 5: currency.Currency.Convert:input_type -> currency.ConvertRequest
-	4, // 6: currency.Currency.Rates:output_type -> currency.RatesResponse
+	3,  // 6: currency.Currency.History:input_type -> currency.HistoryRequest
-	6, // 7: currency.Currency.Convert:output_type -> currency.ConvertResponse
+	2,  // 7: currency.Currency.Codes:output_type -> currency.CodesResponse
-	5, // [5:8] is the sub-list for method output_type
+	6,  // 8: currency.Currency.Rates:output_type -> currency.RatesResponse
-	2, // [2:5] is the sub-list for method input_type
+	8,  // 9: currency.Currency.Convert:output_type -> currency.ConvertResponse
-	2, // [2:2] is the sub-list for extension type_name
+	4,  // 10: currency.Currency.History:output_type -> currency.HistoryResponse
-	2, // [2:2] is the sub-list for extension extendee
+	7,  // [7:11] is the sub-list for method output_type
-	0, // [0:2] is the sub-list for field type_name
+	3,  // [3:7] is the sub-list for method input_type
+	3,  // [3:3] is the sub-list for extension type_name
+	3,  // [3:3] is the sub-list for extension extendee
+	0,  // [0:3] is the sub-list for field type_name
 }
 
 func init() { file_proto_currency_proto_init() }
@@ -546,7 +694,7 @@ func file_proto_currency_proto_init() {
 			}
 		}
 		file_proto_currency_proto_msgTypes[3].Exporter = func(v interface{}, i int) interface{} {
-			switch v := v.(*RatesRequest); i {
+			switch v := v.(*HistoryRequest); i {
 			case 0:
 				return &v.state
 			case 1:
@@ -558,7 +706,7 @@ func file_proto_currency_proto_init() {
 			}
 		}
 		file_proto_currency_proto_msgTypes[4].Exporter = func(v interface{}, i int) interface{} {
-			switch v := v.(*RatesResponse); i {
+			switch v := v.(*HistoryResponse); i {
 			case 0:
 				return &v.state
 			case 1:
@@ -570,7 +718,7 @@ func file_proto_currency_proto_init() {
 			}
 		}
 		file_proto_currency_proto_msgTypes[5].Exporter = func(v interface{}, i int) interface{} {
-			switch v := v.(*ConvertRequest); i {
+			switch v := v.(*RatesRequest); i {
 			case 0:
 				return &v.state
 			case 1:
@@ -582,6 +730,30 @@ func file_proto_currency_proto_init() {
 			}
 		}
 		file_proto_currency_proto_msgTypes[6].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*RatesResponse); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_proto_currency_proto_msgTypes[7].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*ConvertRequest); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_proto_currency_proto_msgTypes[8].Exporter = func(v interface{}, i int) interface{} {
 			switch v := v.(*ConvertResponse); i {
 			case 0:
 				return &v.state
@@ -600,7 +772,7 @@ func file_proto_currency_proto_init() {
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: file_proto_currency_proto_rawDesc,
 			NumEnums:      0,
-			NumMessages:   8,
+			NumMessages:   11,
 			NumExtensions: 0,
 			NumServices:   1,
 		},

currency/proto/currency.pb.micro.go

@@ -45,6 +45,7 @@ type CurrencyService interface {
 	Codes(ctx context.Context, in *CodesRequest, opts ...client.CallOption) (*CodesResponse, error)
 	Rates(ctx context.Context, in *RatesRequest, opts ...client.CallOption) (*RatesResponse, error)
 	Convert(ctx context.Context, in *ConvertRequest, opts ...client.CallOption) (*ConvertResponse, error)
+	History(ctx context.Context, in *HistoryRequest, opts ...client.CallOption) (*HistoryResponse, error)
 }
 
 type currencyService struct {
@@ -89,12 +90,23 @@ func (c *currencyService) Convert(ctx context.Context, in *ConvertRequest, opts
 	return out, nil
 }
 
+func (c *currencyService) History(ctx context.Context, in *HistoryRequest, opts ...client.CallOption) (*HistoryResponse, error) {
+	req := c.c.NewRequest(c.name, "Currency.History", in)
+	out := new(HistoryResponse)
+	err := c.c.Call(ctx, req, out, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
 // Server API for Currency service
 
 type CurrencyHandler interface {
 	Codes(context.Context, *CodesRequest, *CodesResponse) error
 	Rates(context.Context, *RatesRequest, *RatesResponse) error
 	Convert(context.Context, *ConvertRequest, *ConvertResponse) error
+	History(context.Context, *HistoryRequest, *HistoryResponse) error
 }
 
 func RegisterCurrencyHandler(s server.Server, hdlr CurrencyHandler, opts ...server.HandlerOption) error {
@@ -102,6 +114,7 @@ func RegisterCurrencyHandler(s server.Server, hdlr CurrencyHandler, opts ...serv
 		Codes(ctx context.Context, in *CodesRequest, out *CodesResponse) error
 		Rates(ctx context.Context, in *RatesRequest, out *RatesResponse) error
 		Convert(ctx context.Context, in *ConvertRequest, out *ConvertResponse) error
+		History(ctx context.Context, in *HistoryRequest, out *HistoryResponse) error
 	}
 	type Currency struct {
 		currency
@@ -125,3 +138,7 @@ func (h *currencyHandler) Rates(ctx context.Context, in *RatesRequest, out *Rate
 func (h *currencyHandler) Convert(ctx context.Context, in *ConvertRequest, out *ConvertResponse) error {
 	return h.CurrencyHandler.Convert(ctx, in, out)
 }
+
+func (h *currencyHandler) History(ctx context.Context, in *HistoryRequest, out *HistoryResponse) error {
+	return h.CurrencyHandler.History(ctx, in, out)
+}

currency/proto/currency.proto

@@ -8,6 +8,7 @@ service Currency {
 	rpc Codes(CodesRequest) returns (CodesResponse) {}
 	rpc Rates(RatesRequest) returns (RatesResponse) {}
 	rpc Convert(ConvertRequest) returns (ConvertResponse) {}
+	rpc History(HistoryRequest) returns (HistoryResponse) {}
 }
 
 message Code {
@@ -24,6 +25,23 @@ message CodesResponse {
 	repeated Code codes = 1;
 }
 
+// Returns the historic rates for a currency on a given date
+message HistoryRequest {
+	// currency code e.g USD
+	string code = 1;
+	// date formatted as YYYY-MM-DD
+	string date = 2;
+}
+
+message HistoryResponse {
+	// The code of the request
+	string code = 1;
+	// The date requested
+	string date = 2;
+	// The rate for the day as code:rate
+	map<string, double> rates = 3;
+}
+
 // Rates returns the currency rates for a given code e.g USD
 message RatesRequest {
 	// The currency code to get rates for e.g USD