feat: parse and return meta from headers

src/http.ts

@@ -41,25 +41,46 @@ interface ResourceInfo<TResource extends Resource> {
   parameters: Parameters
 }
 
+export interface RequestMeta {
+  requestId: string
+  timestamp: string
+  quotaMax: number
+  quotaRemaining: number
+  quotaResetOn: string
+}
+
 const canonicalizeParameters = (parameters: Parameters): string => {
   const sp = new URLSearchParams(parameters)
   sp.sort()
   return sp.toString().replace(/\+/g, '%20')
 }
 
-const defaultFetch = <T>({ url, method, headers, data }: Request): Promise<T> =>
-  axios({ method, url, headers, data }).then((response) => parser.parse(response.data))
+const defaultFetch = <T>({ url, method, headers, data }: Request): Promise<[T, RequestMeta]> =>
+  axios({ method, url, headers, data }).then((response) => {
+    const responseData = parser.parse(response.data)
+
+    return [
+      responseData,
+      {
+        requestId: response.headers['x-mws-request-id'] ?? responseData.ResponseMetadata.RequestId,
+        timestamp: response.headers['x-mws-timestamp'],
+        quotaMax: Number(response.headers['x-mws-quota-max']),
+        quotaRemaining: Number(response.headers['x-mws-quota-remaining']),
+        quotaResetOn: response.headers['x-mws-quota-resetson'],
+      },
+    ]
+  })
 
 export class HttpClient {
   constructor(
     private options: MWSOptions,
-    private fetch: <T>(meta: Request) => Promise<T> = defaultFetch,
+    private fetch: <T>(meta: Request) => Promise<[T, RequestMeta]> = defaultFetch,
   ) {}
 
   request<TResource extends Resource, TRes>(
     method: HttpMethod,
     info: ResourceInfo<TResource>,
-  ): Promise<TRes> {
+  ): Promise<[TRes, RequestMeta]> {
     const marketplaceUri = this.options.marketplace.webServiceUri
 
     const host = marketplaceUri.replace('https://', '')

src/sections/sellers.ts

@@ -1,7 +1,7 @@
 import { Type } from '@sinclair/typebox'
 import Ajv from 'ajv'
 
-import { HttpClient, Resource } from '../http'
+import { HttpClient, RequestMeta, Resource } from '../http'
 import { ensureArray, parseBoolean } from '../parsing'
 
 interface MarketplaceParticipationsResponse {
@@ -71,8 +71,11 @@ interface MarketplaceParticipations {
 export class Sellers {
   constructor(private httpClient: HttpClient) {}
 
-  async listMarketplaceParticipations(): Promise<MarketplaceParticipations> {
-    const response: MarketplaceParticipationsResponse = await this.httpClient.request('POST', {
+  async listMarketplaceParticipations(): Promise<[MarketplaceParticipations, RequestMeta]> {
+    const [response, meta]: [
+      MarketplaceParticipationsResponse,
+      RequestMeta,
+    ] = await this.httpClient.request('POST', {
       resource: Resource.Sellers,
       version: '2011-07-01',
       action: 'ListMarketplaceParticipations',
@@ -98,7 +101,7 @@ export class Sellers {
     }
 
     if (new Ajv().validate(MarketplaceParticipations, result)) {
-      return result
+      return [result, meta]
     }
 
     throw new Error('TODO for now')