add the currency service

currency/.gitignore

@@ -0,0 +1,2 @@
+
+currency

currency/Dockerfile

@@ -0,0 +1,3 @@
+FROM alpine
+ADD currency /currency
+ENTRYPOINT [ "/currency" ]

currency/Makefile

@@ -0,0 +1,28 @@
+
+GOPATH:=$(shell go env GOPATH)
+.PHONY: init
+init:
+	go get -u github.com/golang/protobuf/proto
+	go get -u github.com/golang/protobuf/protoc-gen-go
+	go get github.com/micro/micro/v3/cmd/protoc-gen-micro
+	go get github.com/micro/micro/v3/cmd/protoc-gen-openapi
+
+.PHONY: api
+api:
+	protoc --openapi_out=. --proto_path=. proto/currency.proto
+
+.PHONY: proto
+proto:
+	protoc --proto_path=. --micro_out=. --go_out=:. proto/currency.proto
+	
+.PHONY: build
+build:
+	go build -o currency *.go
+
+.PHONY: test
+test:
+	go test -v ./... -cover
+
+.PHONY: docker
+docker:
+	docker build . -t currency:latest

currency/README.md

@@ -0,0 +1,6 @@
+Currency conversion powered by ExchangeRate-API
+
+# Currency Service
+
+Fast currency rates and conversion powered by [ExchangeRate-API](https://www.exchangerate-api.com/)
+

currency/config.md

@@ -0,0 +1,8 @@
+# Currency Config
+
+We currently depend on [ExchangeRate-API](https://www.exchangerate-api.com/). The config required is:
+
+- `exchangerate.api` as "https://v6.exchangerate-api.com/v6/"
+- `exchangerate.key` as the api key
+
+

currency/generate.go

@@ -0,0 +1,3 @@
+package main
+
+//go:generate make proto

currency/handler/currency.go

@@ -0,0 +1,105 @@
+package handler
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+
+	"github.com/micro/micro/v3/service/errors"
+	"github.com/micro/micro/v3/service/logger"
+	pb "github.com/micro/services/currency/proto"
+)
+
+type Currency struct {
+	Api string
+}
+
+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")
+	}
+	if len(req.Code) != 3 {
+		return errors.BadRequest("currency.rates", "code is invalid")
+	}
+
+	resp, err := http.Get(c.Api + "/latest/" + req.Code)
+	if err != nil {
+		logger.Errorf("Failed to get rates: %v\n", err)
+		return errors.InternalServerError("currency.rates", "failed to get rates")
+	}
+	defer resp.Body.Close()
+
+	b, _ := ioutil.ReadAll(resp.Body)
+
+	if resp.StatusCode != 200 {
+		logger.Errorf("Failed to get rates (non 200): %d %v\n", resp.StatusCode, string(b))
+		return errors.InternalServerError("currency.rates", "failed to get rates")
+	}
+
+	var respBody map[string]interface{}
+
+	if err := json.Unmarshal(b, &respBody); err != nil {
+		logger.Errorf("Failed to unmarshal rates: %v\n", err)
+		return errors.InternalServerError("currency.rates", "failed to get rates")
+	}
+
+	rates, ok := respBody["conversion_rates"].(map[string]interface{})
+	if !ok {
+		logger.Errorf("Failed to convert rates to map[string]interface{}: %v\n", ok)
+		return errors.InternalServerError("currency.rates", "failed to get rates")
+	}
+
+	rsp.Code = req.Code
+	rsp.Rates = make(map[string]float64)
+
+	for code, rate := range rates {
+		rsp.Rates[code], _ = rate.(float64)
+	}
+
+	return nil
+}
+
+func (c *Currency) Convert(ctx context.Context, req *pb.ConvertRequest, rsp *pb.ConvertResponse) error {
+	if len(req.From) != 3 {
+		return errors.BadRequest("currency.convert", "invalid from code")
+	}
+	if len(req.To) != 3 {
+		return errors.BadRequest("currency.convert", "invalid to code")
+	}
+
+	uri := fmt.Sprintf("%s/pair/%s/%s", c.Api, req.From, req.To)
+
+	if req.Amount > 0.0 {
+		uri = fmt.Sprintf("%s/%v", uri, req.Amount)
+	}
+
+	resp, err := http.Get(uri)
+	if err != nil {
+		logger.Errorf("Failed to convert: %v\n", err)
+		return errors.InternalServerError("currency.convert", "failed to convert")
+	}
+	defer resp.Body.Close()
+
+	b, _ := ioutil.ReadAll(resp.Body)
+
+	if resp.StatusCode != 200 {
+		logger.Errorf("Failed to get convert (non 200): %d %v\n", resp.StatusCode, string(b))
+		return errors.InternalServerError("currency.convert", "failed to convert")
+	}
+
+	var respBody map[string]interface{}
+
+	if err := json.Unmarshal(b, &respBody); err != nil {
+		logger.Errorf("Failed to unmarshal conversion: %v\n", err)
+		return errors.InternalServerError("currency.convet", "failed to convert")
+	}
+
+	rsp.From = req.From
+	rsp.To = req.To
+	rsp.Rate, _ = respBody["conversion_rate"].(float64)
+	rsp.Amount, _ = respBody["conversion_result"].(float64)
+
+	return nil
+}

currency/main.go

@@ -0,0 +1,45 @@
+package main
+
+import (
+	"github.com/micro/services/currency/handler"
+	pb "github.com/micro/services/currency/proto"
+
+	"github.com/micro/micro/v3/service"
+	"github.com/micro/micro/v3/service/config"
+	"github.com/micro/micro/v3/service/logger"
+)
+
+func main() {
+	// Create service
+	srv := service.New(
+		service.Name("currency"),
+		service.Version("latest"),
+	)
+
+	v, err := config.Get("exchangerate.api")
+	if err != nil {
+		logger.Fatalf("exchangerate.api config not found: %v", err)
+	}
+	api := v.String("")
+	if len(api) == 0 {
+		logger.Fatal("exchangerate.api config not found")
+	}
+	v, err = config.Get("exchangerate.key")
+	if err != nil {
+		logger.Fatalf("exchangerate.key config not found: %v", err)
+	}
+	key := v.String("")
+	if len(key) == 0 {
+		logger.Fatal("exchangerate.key config not found")
+	}
+
+	// Register handler
+	pb.RegisterCurrencyHandler(srv.Server(), &handler.Currency{
+		Api: api + key,
+	})
+
+	// Run service
+	if err := srv.Run(); err != nil {
+		logger.Fatal(err)
+	}
+}

currency/micro.mu

@@ -0,0 +1 @@
+service currency

currency/proto/currency.pb.go

@@ -0,0 +1,417 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.26.0
+// 	protoc        v3.15.6
+// source: proto/currency.proto
+
+package currency
+
+import (
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sync "sync"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+// Rates returns the currency rates for a given code e.g USD
+type RatesRequest struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// The currency code to get rates for
+	Code string `protobuf:"bytes,1,opt,name=code,proto3" json:"code,omitempty"`
+}
+
+func (x *RatesRequest) Reset() {
+	*x = RatesRequest{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_proto_currency_proto_msgTypes[0]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *RatesRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*RatesRequest) ProtoMessage() {}
+
+func (x *RatesRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_proto_currency_proto_msgTypes[0]
+	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 RatesRequest.ProtoReflect.Descriptor instead.
+func (*RatesRequest) Descriptor() ([]byte, []int) {
+	return file_proto_currency_proto_rawDescGZIP(), []int{0}
+}
+
+func (x *RatesRequest) GetCode() string {
+	if x != nil {
+		return x.Code
+	}
+	return ""
+}
+
+type RatesResponse struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	Code string `protobuf:"bytes,1,opt,name=code,proto3" json:"code,omitempty"`
+	// The rates for the given code
+	Rates map[string]float64 `protobuf:"bytes,2,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 *RatesResponse) Reset() {
+	*x = RatesResponse{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_proto_currency_proto_msgTypes[1]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *RatesResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*RatesResponse) ProtoMessage() {}
+
+func (x *RatesResponse) ProtoReflect() protoreflect.Message {
+	mi := &file_proto_currency_proto_msgTypes[1]
+	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 RatesResponse.ProtoReflect.Descriptor instead.
+func (*RatesResponse) Descriptor() ([]byte, []int) {
+	return file_proto_currency_proto_rawDescGZIP(), []int{1}
+}
+
+func (x *RatesResponse) GetCode() string {
+	if x != nil {
+		return x.Code
+	}
+	return ""
+}
+
+func (x *RatesResponse) GetRates() map[string]float64 {
+	if x != nil {
+		return x.Rates
+	}
+	return nil
+}
+
+// Convert returns the currency conversion rate between two pairs e.g USD/GBP
+type ConvertRequest struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// base code to convert from
+	From string `protobuf:"bytes,1,opt,name=from,proto3" json:"from,omitempty"`
+	// target code to convert to
+	To string `protobuf:"bytes,2,opt,name=to,proto3" json:"to,omitempty"`
+	// optional amoun to convert
+	Amount float64 `protobuf:"fixed64,3,opt,name=amount,proto3" json:"amount,omitempty"`
+}
+
+func (x *ConvertRequest) Reset() {
+	*x = ConvertRequest{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_proto_currency_proto_msgTypes[2]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *ConvertRequest) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*ConvertRequest) ProtoMessage() {}
+
+func (x *ConvertRequest) ProtoReflect() protoreflect.Message {
+	mi := &file_proto_currency_proto_msgTypes[2]
+	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 ConvertRequest.ProtoReflect.Descriptor instead.
+func (*ConvertRequest) Descriptor() ([]byte, []int) {
+	return file_proto_currency_proto_rawDescGZIP(), []int{2}
+}
+
+func (x *ConvertRequest) GetFrom() string {
+	if x != nil {
+		return x.From
+	}
+	return ""
+}
+
+func (x *ConvertRequest) GetTo() string {
+	if x != nil {
+		return x.To
+	}
+	return ""
+}
+
+func (x *ConvertRequest) GetAmount() float64 {
+	if x != nil {
+		return x.Amount
+	}
+	return 0
+}
+
+type ConvertResponse struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// the base code
+	From string `protobuf:"bytes,1,opt,name=from,proto3" json:"from,omitempty"`
+	// the target code
+	To string `protobuf:"bytes,2,opt,name=to,proto3" json:"to,omitempty"`
+	// conversion rate
+	Rate float64 `protobuf:"fixed64,3,opt,name=rate,proto3" json:"rate,omitempty"`
+	// converted amount if specified
+	Amount float64 `protobuf:"fixed64,4,opt,name=amount,proto3" json:"amount,omitempty"`
+}
+
+func (x *ConvertResponse) Reset() {
+	*x = ConvertResponse{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_proto_currency_proto_msgTypes[3]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *ConvertResponse) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*ConvertResponse) ProtoMessage() {}
+
+func (x *ConvertResponse) 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 ConvertResponse.ProtoReflect.Descriptor instead.
+func (*ConvertResponse) Descriptor() ([]byte, []int) {
+	return file_proto_currency_proto_rawDescGZIP(), []int{3}
+}
+
+func (x *ConvertResponse) GetFrom() string {
+	if x != nil {
+		return x.From
+	}
+	return ""
+}
+
+func (x *ConvertResponse) GetTo() string {
+	if x != nil {
+		return x.To
+	}
+	return ""
+}
+
+func (x *ConvertResponse) GetRate() float64 {
+	if x != nil {
+		return x.Rate
+	}
+	return 0
+}
+
+func (x *ConvertResponse) GetAmount() float64 {
+	if x != nil {
+		return x.Amount
+	}
+	return 0
+}
+
+var File_proto_currency_proto protoreflect.FileDescriptor
+
+var file_proto_currency_proto_rawDesc = []byte{
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+	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
+}
+
+var (
+	file_proto_currency_proto_rawDescOnce sync.Once
+	file_proto_currency_proto_rawDescData = file_proto_currency_proto_rawDesc
+)
+
+func file_proto_currency_proto_rawDescGZIP() []byte {
+	file_proto_currency_proto_rawDescOnce.Do(func() {
+		file_proto_currency_proto_rawDescData = protoimpl.X.CompressGZIP(file_proto_currency_proto_rawDescData)
+	})
+	return file_proto_currency_proto_rawDescData
+}
+
+var file_proto_currency_proto_msgTypes = make([]protoimpl.MessageInfo, 5)
+var file_proto_currency_proto_goTypes = []interface{}{
+	(*RatesRequest)(nil),    // 0: currency.RatesRequest
+	(*RatesResponse)(nil),   // 1: currency.RatesResponse
+	(*ConvertRequest)(nil),  // 2: currency.ConvertRequest
+	(*ConvertResponse)(nil), // 3: currency.ConvertResponse
+	nil,                     // 4: currency.RatesResponse.RatesEntry
+}
+var file_proto_currency_proto_depIdxs = []int32{
+	4, // 0: currency.RatesResponse.rates:type_name -> currency.RatesResponse.RatesEntry
+	0, // 1: currency.Currency.Rates:input_type -> currency.RatesRequest
+	2, // 2: currency.Currency.Convert:input_type -> currency.ConvertRequest
+	1, // 3: currency.Currency.Rates:output_type -> currency.RatesResponse
+	3, // 4: currency.Currency.Convert:output_type -> currency.ConvertResponse
+	3, // [3:5] is the sub-list for method output_type
+	1, // [1:3] is the sub-list for method input_type
+	1, // [1:1] is the sub-list for extension type_name
+	1, // [1:1] is the sub-list for extension extendee
+	0, // [0:1] is the sub-list for field type_name
+}
+
+func init() { file_proto_currency_proto_init() }
+func file_proto_currency_proto_init() {
+	if File_proto_currency_proto != nil {
+		return
+	}
+	if !protoimpl.UnsafeEnabled {
+		file_proto_currency_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*RatesRequest); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+		file_proto_currency_proto_msgTypes[1].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[2].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[3].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*ConvertResponse); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: file_proto_currency_proto_rawDesc,
+			NumEnums:      0,
+			NumMessages:   5,
+			NumExtensions: 0,
+			NumServices:   1,
+		},
+		GoTypes:           file_proto_currency_proto_goTypes,
+		DependencyIndexes: file_proto_currency_proto_depIdxs,
+		MessageInfos:      file_proto_currency_proto_msgTypes,
+	}.Build()
+	File_proto_currency_proto = out.File
+	file_proto_currency_proto_rawDesc = nil
+	file_proto_currency_proto_goTypes = nil
+	file_proto_currency_proto_depIdxs = nil
+}

currency/proto/currency.pb.micro.go

@@ -0,0 +1,110 @@
+// Code generated by protoc-gen-micro. DO NOT EDIT.
+// source: proto/currency.proto
+
+package currency
+
+import (
+	fmt "fmt"
+	proto "github.com/golang/protobuf/proto"
+	math "math"
+)
+
+import (
+	context "context"
+	api "github.com/micro/micro/v3/service/api"
+	client "github.com/micro/micro/v3/service/client"
+	server "github.com/micro/micro/v3/service/server"
+)
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion3 // please upgrade the proto package
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ api.Endpoint
+var _ context.Context
+var _ client.Option
+var _ server.Option
+
+// Api Endpoints for Currency service
+
+func NewCurrencyEndpoints() []*api.Endpoint {
+	return []*api.Endpoint{}
+}
+
+// Client API for Currency service
+
+type CurrencyService interface {
+	Rates(ctx context.Context, in *RatesRequest, opts ...client.CallOption) (*RatesResponse, error)
+	Convert(ctx context.Context, in *ConvertRequest, opts ...client.CallOption) (*ConvertResponse, error)
+}
+
+type currencyService struct {
+	c    client.Client
+	name string
+}
+
+func NewCurrencyService(name string, c client.Client) CurrencyService {
+	return &currencyService{
+		c:    c,
+		name: name,
+	}
+}
+
+func (c *currencyService) Rates(ctx context.Context, in *RatesRequest, opts ...client.CallOption) (*RatesResponse, error) {
+	req := c.c.NewRequest(c.name, "Currency.Rates", in)
+	out := new(RatesResponse)
+	err := c.c.Call(ctx, req, out, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+func (c *currencyService) Convert(ctx context.Context, in *ConvertRequest, opts ...client.CallOption) (*ConvertResponse, error) {
+	req := c.c.NewRequest(c.name, "Currency.Convert", in)
+	out := new(ConvertResponse)
+	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 {
+	Rates(context.Context, *RatesRequest, *RatesResponse) error
+	Convert(context.Context, *ConvertRequest, *ConvertResponse) error
+}
+
+func RegisterCurrencyHandler(s server.Server, hdlr CurrencyHandler, opts ...server.HandlerOption) error {
+	type currency interface {
+		Rates(ctx context.Context, in *RatesRequest, out *RatesResponse) error
+		Convert(ctx context.Context, in *ConvertRequest, out *ConvertResponse) error
+	}
+	type Currency struct {
+		currency
+	}
+	h := &currencyHandler{hdlr}
+	return s.Handle(s.NewHandler(&Currency{h}, opts...))
+}
+
+type currencyHandler struct {
+	CurrencyHandler
+}
+
+func (h *currencyHandler) Rates(ctx context.Context, in *RatesRequest, out *RatesResponse) error {
+	return h.CurrencyHandler.Rates(ctx, in, out)
+}
+
+func (h *currencyHandler) Convert(ctx context.Context, in *ConvertRequest, out *ConvertResponse) error {
+	return h.CurrencyHandler.Convert(ctx, in, out)
+}

currency/proto/currency.proto

@@ -0,0 +1,44 @@
+syntax = "proto3";
+
+package currency;
+
+option go_package = "./proto;currency";
+
+service Currency {
+	rpc Rates(RatesRequest) returns (RatesResponse) {}
+	rpc Convert(ConvertRequest) returns (ConvertResponse) {}
+}
+
+// Rates returns the currency rates for a given code e.g USD
+message RatesRequest {
+	// The currency code to get rates for
+	string code = 1;
+}
+
+message RatesResponse {
+	string code = 1;
+	// The rates for the given code
+	map<string, double> rates = 2;
+}
+
+
+// Convert returns the currency conversion rate between two pairs e.g USD/GBP
+message ConvertRequest {
+	// base code to convert from
+	string from = 1;
+	// target code to convert to
+	string to = 2;
+	// optional amoun to convert
+	double amount = 3;
+}
+
+message ConvertResponse {
+	// the base code
+	string from = 1;
+	// the target code
+	string to = 2;
+	// conversion rate
+	double rate = 3;
+	// converted amount if specified
+	double amount = 4;
+}

currency/publicapi.json

@@ -0,0 +1,9 @@
+{
+  "name": "currency",
+  "icon": "💱",
+  "category": "money",
+  "pricing": {
+    "Currency.Rates", 100,
+    "Currency.Convert", 100
+  }
+}