fix: redundant class interface

BREAKING CHANGE: Interfaces are not exported anymore.
It is necessary to use class as a type directly, e.g. `Klarna` instead of `IKlarnaInstance`

src/api/checkout-v3/checkout-v3.ts

@@ -1,18 +1,12 @@
 import { HttpRequest } from '../../http-request';
 import { IOrderBody, IOrderResponse } from './interface';
 
-export interface ICheckoutV3 {
-  createOrder(body: IOrderBody): Promise<IOrderResponse>;
-  retrieveOrder(orderId: string): Promise<IOrderResponse>;
-  updateOrder(orderId: string, body: IOrderBody): Promise<IOrderResponse>;
-}
-
 /*
  * Documentation: https://developers.klarna.com/api/#checkout-api
  */
 export class CheckoutV3 extends HttpRequest {
   /*
-    Documentation: https://developers.klarna.com/api/#checkout-api-create-a-new-order  
+    Documentation: https://developers.klarna.com/api/#checkout-api-create-a-new-order
   */
   createOrder(body: IOrderBody): Promise<IOrderResponse> {
     return this.invoke(`POST`, `/checkout/v3/orders`, body);

src/api/customer-token-v1/customer-token-v1.ts

@@ -1,10 +1,6 @@
 import { HttpRequest, IResponse } from '../../http-request';
 import { ICustomerTokenBody } from './interface';
 
-export interface ICustomerTokenV1 {
-  order(token: string, body: ICustomerTokenBody): Promise<IResponse>;
-}
-
 /**
  * Docs: https://developers.klarna.com/documentation/klarna-payments/integration-guide/place-order/#4-3-place-recurring-order-tokenization
  */

src/api/order-management-v1/captures/captures.ts

@@ -1,10 +1,6 @@
 import { HttpRequest, IResponse } from '../../../http-request';
 import { IOrderLine } from '../../checkout-v3';
 
-export interface ICaptures {
-  capture(orderId: string, body: ICaptureBody): Promise<IResponse>;
-}
-
 interface ICaptureBody {
   captured_amount: number;
   description?: string;

src/api/order-management-v1/order-management-v1.ts

@@ -1,21 +1,15 @@
-import { Orders, IOrders } from './orders';
-import { Captures, ICaptures } from './captures';
-import { Refunds, IRefunds } from './refunds';
+import { Orders } from './orders';
+import { Captures } from './captures';
+import { Refunds } from './refunds';
 import { IOptions } from '../../http-request';
 
-export interface IOrderManagementV1 {
-  orders: IOrders;
-  captures: ICaptures;
-  refunds: IRefunds;
-}
-
 /**
  * Docs: https://developers.klarna.com/api/#order-management-api
  */
 export class OrderManagementV1 {
-  orders: IOrders;
-  captures: ICaptures;
-  refunds: IRefunds;
+  orders: Orders;
+  captures: Captures;
+  refunds: Refunds;
 
   constructor(options: IOptions) {
     this.orders = new Orders(options);

src/api/order-management-v1/orders/orders.ts

@@ -1,12 +1,5 @@
 import { HttpRequest, IResponse } from '../../../http-request';
 
-export interface IOrders {
-  acknowledge(orderId: string): Promise<IResponse>;
-  cancel(orderId: string): Promise<IResponse>;
-  releaseRemainingAuthorization(orderId: string): Promise<IResponse>;
-  getOrder(orderId: string): Promise<IResponse>;
-}
-
 interface IUpdateMerchantReferenceBody {
   merchant_reference1: string;
   merchant_reference2: string;

src/api/order-management-v1/refunds/refunds.ts

@@ -8,10 +8,6 @@ interface IRefundBody {
   order_lines: Array<IOrderLine>;
 }
 
-export interface IRefunds {
-  create(orderId: string, body: IRefundBody): Promise<IResponse>;
-}
-
 export class Refunds extends HttpRequest {
   /**
    * https://developers.klarna.com/api/#order-management-api-create-a-refund

src/index.ts

@@ -1,10 +1,7 @@
 import { IOptions } from './http-request';
-import { CheckoutV3, ICheckoutV3 } from './api/checkout-v3';
-import { CustomerTokenV1, ICustomerTokenV1 } from './api/customer-token-v1';
-import {
-  IOrderManagementV1,
-  OrderManagementV1,
-} from './api/order-management-v1';
+import { CheckoutV3 } from './api/checkout-v3';
+import { CustomerTokenV1 } from './api/customer-token-v1';
+import { OrderManagementV1 } from './api/order-management-v1';
 export * from './crystallize-helpers';
 
 interface IConfig {
@@ -13,16 +10,10 @@ interface IConfig {
   apiEndpoint?: string;
 }
 
-export interface IKlarnaInstance {
-  checkoutV3: ICheckoutV3;
-  customerTokenV1: ICustomerTokenV1;
-  orderManagementV1: IOrderManagementV1;
-}
-
-export class Klarna implements IKlarnaInstance {
-  checkoutV3: ICheckoutV3;
-  customerTokenV1: ICustomerTokenV1;
-  orderManagementV1: IOrderManagementV1;
+export class Klarna {
+  checkoutV3: CheckoutV3;
+  customerTokenV1: CustomerTokenV1;
+  orderManagementV1: OrderManagementV1;
 
   constructor(config: IConfig) {
     let { apiEndpoint } = config;

test/checkout.spec.ts

@@ -1,13 +1,13 @@
 import * as dotenv from 'dotenv';
-import { Klarna, IKlarnaInstance } from '../src';
+import { Klarna } from '../src';
 
 dotenv.config();
 
 const username = process.env.KLARNA_USERNAME;
 const password = process.env.KLARNA_PASSWORD;
 
 describe('checkout v3', () => {
-  let klarna: IKlarnaInstance;
+  let klarna: Klarna;
   let orderId: string;
 
   beforeAll(done => {