feat(api): add currencies endpoint to v3

api/spec/src/v3/currencies/currency.tsp

@@ -0,0 +1,45 @@
+import "../shared/index.tsp";
+
+namespace Currencies;
+
+/**
+ * Currency describes a currency supported by the billing system.
+ */
+@friendlyName("BillingCurrency")
+model Currency {
+  /**
+   * Standard ISO 4217 code.
+   */
+  @visibility(Lifecycle.Read)
+  code: Shared.CurrencyCode;
+
+  /**
+   * English name of the currency.
+   */
+  @visibility(Lifecycle.Read)
+  name: string;
+
+  /**
+   * Symbol representation of the currency.
+   */
+  @visibility(Lifecycle.Read)
+  symbol: string;
+
+  /**
+   * Disambiguation symbol for the currency.
+   */
+  @visibility(Lifecycle.Read)
+  disambiguate_symbol: string;
+
+  /**
+   * Number of subunits in the currency.
+   */
+  @visibility(Lifecycle.Read)
+  subunits: uint32;
+
+  /**
+   * Smallest denomination of the currency.
+   */
+  @visibility(Lifecycle.Read)
+  smallest_denomination: uint8;
+}

api/spec/src/v3/currencies/index.tsp

@@ -0,0 +1,2 @@
+import "./currency.tsp";
+import "./operations.tsp";

api/spec/src/v3/currencies/operations.tsp

@@ -0,0 +1,44 @@
+import "@typespec/http";
+import "@typespec/rest";
+import "@typespec/openapi";
+import "@typespec/openapi3";
+import "../common/error.tsp";
+import "../common/parameters.tsp";
+import "../shared/index.tsp";
+import "./currency.tsp";
+
+using TypeSpec.Http;
+using TypeSpec.OpenAPI;
+
+namespace Currencies;
+
+/**
+ * Filter options for listing currencies.
+ */
+@friendlyName("ListCurrenciesParamsFilter")
+model ListCurrenciesParamsFilter {
+  /**
+   * Filter currencies by code.
+   */
+}
+
+/**
+ * List currencies response.
+ */
+@friendlyName("CurrenciesResponse")
+model CurrenciesResponse {
+  @Http.statusCode _: 200;
+
+  @pageItems
+  data: Currency[];
+}
+
+interface CurrenciesOperations {
+  /**
+   * List all supported currencies.
+   */
+  @get
+  @operationId("list-currencies")
+  @summary("List currencies")
+  list(): CurrenciesResponse | Common.ErrorResponses;
+}

api/spec/src/v3/konnect.tsp

@@ -81,6 +81,10 @@ interface AppsEndpoints extends Apps.AppsOperations {}
 @tag(Shared.BillingTag)
 interface BillingProfilesEndpoints extends Billing.BillingProfilesOperations {}
 
+@route("/openmeter/currencies")
+@tag(Shared.BillingTag)
+interface CurrenciesEndpoints extends Currencies.CurrenciesOperations {}
+
 /**
  * The system account access token is meant for automations and integrations that are not directly associated with a human identity.
  */

api/spec/src/v3/openmeter.tsp

@@ -9,6 +9,7 @@ import "./customers/index.tsp";
 import "./subscriptions/index.tsp";
 import "./apps/index.tsp";
 import "./billing/index.tsp";
+import "./currencies/index.tsp";
 
 using TypeSpec.Http;
 using TypeSpec.OpenAPI;
@@ -76,3 +77,7 @@ interface AppsEndpoints extends Apps.AppsOperations {}
 @route("/openmeter/profiles")
 @tag(Shared.BillingTag)
 interface BillingProfilesEndpoints extends Billing.BillingProfilesOperations {}
+
+@route("/openmeter/currencies")
+@tag(Shared.BillingTag)
+interface CurrenciesEndpoints extends Currencies.CurrenciesOperations {}

api/v3/handlers/currencies/convert.go

@@ -0,0 +1,17 @@
+package currencies
+
+import (
+	"github.com/invopop/gobl/currency"
+	v3 "github.com/openmeterio/openmeter/api/v3"
+)
+
+func MapCurrencyToAPI(currency *currency.Def) v3.BillingCurrency {
+	return v3.BillingCurrency{
+		Code:                 v3.CurrencyCode(currency.ISOCode),
+		DisambiguateSymbol:   currency.DisambiguateSymbol,
+		Name:                 currency.Name,
+		SmallestDenomination: uint8(currency.SmallestDenomination),
+		Subunits:             currency.Subunits,
+		Symbol:               currency.Symbol,
+	}
+}

api/v3/handlers/currencies/handler.go

@@ -0,0 +1,22 @@
+package currencies
+
+import (
+	"github.com/openmeterio/openmeter/openmeter/currencies"
+	"github.com/openmeterio/openmeter/pkg/framework/transport/httptransport"
+)
+
+type Handler interface {
+	ListCurrencies() ListCurrenciesHandler
+}
+
+type handler struct {
+	options         []httptransport.HandlerOption
+	currencyService currencies.CurrencyService
+}
+
+func New(currencyService currencies.CurrencyService, options ...httptransport.HandlerOption) Handler {
+	return &handler{
+		options:         options,
+		currencyService: currencyService,
+	}
+}

api/v3/handlers/currencies/list.go

@@ -0,0 +1,41 @@
+package currencies
+
+import (
+	"context"
+	"net/http"
+
+	"github.com/invopop/gobl/currency"
+	v3 "github.com/openmeterio/openmeter/api/v3"
+	"github.com/openmeterio/openmeter/pkg/framework/commonhttp"
+	"github.com/openmeterio/openmeter/pkg/framework/transport/httptransport"
+	"github.com/samber/lo"
+)
+
+type (
+	ListCurrenciesRequest  struct{}
+	ListCurrenciesResponse []v3.BillingCurrency
+	ListCurrenciesHandler  httptransport.Handler[ListCurrenciesRequest, ListCurrenciesResponse]
+)
+
+func (h *handler) ListCurrencies() ListCurrenciesHandler {
+	return httptransport.NewHandler(
+		func(ctx context.Context, r *http.Request) (ListCurrenciesRequest, error) {
+			return ListCurrenciesRequest{}, nil
+		},
+		func(ctx context.Context, request ListCurrenciesRequest) (ListCurrenciesResponse, error) {
+			defs, err := h.currencyService.ListCurrencies()
+			if err != nil {
+				return nil, err
+			}
+
+			return lo.Map(defs, func(def *currency.Def, _ int) v3.BillingCurrency {
+				return MapCurrencyToAPI(def)
+			}), nil
+		},
+		commonhttp.JSONResponseEncoderWithStatus[ListCurrenciesResponse](http.StatusOK),
+		httptransport.AppendOptions(
+			h.options,
+			httptransport.WithOperationName("listCurrencies"),
+		)...,
+	)
+}

api/v3/openapi.yaml

@@ -79,6 +79,26 @@ paths:
           $ref: '#/components/responses/NotFound'
       tags:
         - OpenMeter Apps
+  /openmeter/currencies:
+    get:
+      operationId: list-currencies
+      summary: List currencies
+      description: List all supported currencies.
+      responses:
+        '200':
+          description: List currencies response.
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/CurrenciesResponse'
+        '400':
+          $ref: '#/components/responses/BadRequest'
+        '401':
+          $ref: '#/components/responses/Unauthorized'
+        '403':
+          $ref: '#/components/responses/Forbidden'
+      tags:
+        - OpenMeter Billing
   /openmeter/customers:
     post:
       operationId: create-customer
@@ -1798,6 +1818,44 @@ components:
         - stripe
         - external_invoicing
       description: The type of the app.
+    BillingCurrency:
+      type: object
+      required:
+        - code
+        - name
+        - symbol
+        - disambiguate_symbol
+        - subunits
+        - smallest_denomination
+      properties:
+        code:
+          allOf:
+            - $ref: '#/components/schemas/CurrencyCode'
+          description: Standard ISO 4217 code.
+          readOnly: true
+        name:
+          type: string
+          description: English name of the currency.
+          readOnly: true
+        symbol:
+          type: string
+          description: Symbol representation of the currency.
+          readOnly: true
+        disambiguate_symbol:
+          type: string
+          description: Disambiguation symbol for the currency.
+          readOnly: true
+        subunits:
+          type: integer
+          format: uint32
+          description: Number of subunits in the currency.
+          readOnly: true
+        smallest_denomination:
+          type: integer
+          format: uint8
+          description: Smallest denomination of the currency.
+          readOnly: true
+      description: Currency describes a currency supported by the billing system.
     BillingCustomer:
       type: object
       required:
@@ -2786,6 +2844,16 @@ components:
           example:
             type: $.type
       description: Meter create request.
+    CurrenciesResponse:
+      type: object
+      required:
+        - data
+      properties:
+        data:
+          type: array
+          items:
+            $ref: '#/components/schemas/BillingCurrency'
+      description: List currencies response.
     CurrencyCode:
       type: string
       minLength: 3

api/v3/server/routes.go

@@ -139,3 +139,9 @@ func (s *Server) CreateCustomerStripeCheckoutSession(w http.ResponseWriter, r *h
 func (s *Server) CreateCustomerStripePortalSession(w http.ResponseWriter, r *http.Request, customerId api.ULID) {
 	s.customersBillingHandler.CreateCustomerStripePortalSession().With(customerId).ServeHTTP(w, r)
 }
+
+// Currencies
+
+func (s *Server) ListCurrencies(w http.ResponseWriter, r *http.Request) {
+	s.currenciesHandler.ListCurrencies().ServeHTTP(w, r)
+}

api/v3/server/server.go

@@ -16,6 +16,7 @@ import (
 	"github.com/openmeterio/openmeter/api/v3/apierrors"
 	appshandler "github.com/openmeterio/openmeter/api/v3/handlers/apps"
 	billingprofileshandler "github.com/openmeterio/openmeter/api/v3/handlers/billingprofiles"
+	currencieshandler "github.com/openmeterio/openmeter/api/v3/handlers/currencies"
 	customershandler "github.com/openmeterio/openmeter/api/v3/handlers/customers"
 	customersbillinghandler "github.com/openmeterio/openmeter/api/v3/handlers/customers/billing"
 	customersentitlementhandler "github.com/openmeterio/openmeter/api/v3/handlers/customers/entitlementaccess"
@@ -27,6 +28,7 @@ import (
 	"github.com/openmeterio/openmeter/openmeter/app"
 	appstripe "github.com/openmeterio/openmeter/openmeter/app/stripe"
 	"github.com/openmeterio/openmeter/openmeter/billing"
+	"github.com/openmeterio/openmeter/openmeter/currencies"
 	"github.com/openmeterio/openmeter/openmeter/customer"
 	"github.com/openmeterio/openmeter/openmeter/entitlement"
 	"github.com/openmeterio/openmeter/openmeter/ingest"
@@ -58,6 +60,7 @@ type Config struct {
 	PlanSubscriptionService plansubscription.PlanSubscriptionService
 	StripeService           appstripe.Service
 	SubscriptionService     subscription.Service
+	CurrencyService         currencies.CurrencyService
 }
 
 func (c *Config) Validate() error {
@@ -115,6 +118,10 @@ func (c *Config) Validate() error {
 		errs = append(errs, errors.New("subscription service is required"))
 	}
 
+	if c.CurrencyService == nil {
+		errs = append(errs, errors.New("currency service is required"))
+	}
+
 	return errors.Join(errs...)
 }
 
@@ -132,6 +139,7 @@ type Server struct {
 	metersHandler               metershandler.Handler
 	subscriptionsHandler        subscriptionshandler.Handler
 	billingProfilesHandler      billingprofileshandler.Handler
+	currenciesHandler           currencieshandler.Handler
 }
 
 // Make sure we conform to ServerInterface
@@ -173,6 +181,7 @@ func NewServer(config *Config) (*Server, error) {
 	metersHandler := metershandler.New(resolveNamespace, config.MeterService, httptransport.WithErrorHandler(config.ErrorHandler))
 	subscriptionsHandler := subscriptionshandler.New(resolveNamespace, config.CustomerService, config.PlanService, config.PlanSubscriptionService, config.SubscriptionService, httptransport.WithErrorHandler(config.ErrorHandler))
 	billingProfilesHandler := billingprofileshandler.New(resolveNamespace, config.BillingService, httptransport.WithErrorHandler(config.ErrorHandler))
+	currenciesHandler := currencieshandler.New(config.CurrencyService, httptransport.WithErrorHandler(config.ErrorHandler))
 
 	return &Server{
 		Config:                      config,
@@ -185,6 +194,7 @@ func NewServer(config *Config) (*Server, error) {
 		metersHandler:               metersHandler,
 		subscriptionsHandler:        subscriptionsHandler,
 		billingProfilesHandler:      billingProfilesHandler,
+		currenciesHandler:           currenciesHandler,
 	}, nil
 }
 

app/common/currency.go

@@ -0,0 +1,15 @@
+package common
+
+import (
+	"github.com/google/wire"
+	"github.com/openmeterio/openmeter/openmeter/currencies"
+	"github.com/openmeterio/openmeter/openmeter/currencies/service"
+)
+
+var Currency = wire.NewSet(
+	NewCurrencyService,
+)
+
+func NewCurrencyService() currencies.CurrencyService {
+	return service.New()
+}

cmd/server/main.go

@@ -147,6 +147,7 @@ func main() {
 			AppCustomInvoicing:          app.AppRegistry.CustomInvoicing,
 			Billing:                     app.Billing,
 			BillingFeatureSwitches:      conf.Billing.FeatureSwitches,
+			CurrencyService:             app.CurrencyService,
 			Customer:                    app.Customer,
 			DebugConnector:              debugConnector,
 			ErrorHandler:                errorsx.NewSlogHandler(logger),