feat: allow Blob response thanks to responseType parameter (#163)

Co-authored-by: Vincent Germain <[email protected]>

Author: QuiiBz

packages/clients/src/scw/fetch/__tests__/response-parser.ts

@@ -6,7 +6,7 @@ import { fixLegacyTotalCount, responseParser } from '../response-parser'
 
 const SIMPLE_REQ_BODY = { 'what-is-life': 42 }
 
-const convertObjToBuffer = (obj: JSON): Buffer => {
+const convertObjToBuffer = (obj: unknown): Buffer => {
   const str = JSON.stringify(obj)
   const bytes = new TextEncoder().encode(str)
 
@@ -19,24 +19,35 @@ const unmarshalJSON = (obj: unknown) => {
   return obj
 }
 
-const makeValidJSONResponse = (
-  value: JSON | null = SIMPLE_REQ_BODY,
+const makeResponse = (
+  value: unknown,
   status = 200,
+  contentType: string | undefined = undefined,
 ) =>
   new Response(value !== null ? convertObjToBuffer(value) : value, {
-    headers: { 'Content-Type': 'application/json' },
+    headers: contentType ? { 'Content-Type': contentType } : undefined,
     status,
   })
 
-const makeValidTextResponse = (value: string | null, status = 200) =>
+const makeJSONResponse = (value: JSON = SIMPLE_REQ_BODY, status = 200) =>
+  makeResponse(value, status, 'application/json')
+
+const makeTextResponse = (value: string, status = 200) =>
   new Response(value, {
     headers: { 'Content-Type': 'plain/text' },
     status,
   })
 
 describe(`responseParser`, () => {
-  const parseJson = responseParser(unmarshalJSON)
-  const parseAsIs = responseParser(<T>(response: unknown) => response as T)
+  const parseJson = responseParser(unmarshalJSON, 'json')
+  const parseAsIs = responseParser(
+    <T>(response: unknown) => response as T,
+    'json',
+  )
+  const parseBlob = responseParser(
+    <T>(response: unknown) => response as T,
+    'blob',
+  )
 
   it(`triggers a type error for non 'Response' object`, () =>
     expect(
@@ -87,12 +98,13 @@ describe(`responseParser`, () => {
   })
 
   it(`triggers an error for unsuccessful unmarshalling`, async () => {
-    const validResponse = makeValidJSONResponse()
+    const validResponse = makeJSONResponse()
+    const emptyContentTypeResponse = makeResponse('some-text', 200, '')
 
     await expect(
       responseParser(() => {
         throw new Error(`couldn't unwrap response value`)
-      })(validResponse.clone()),
+      }, 'json')(validResponse.clone()),
     ).rejects.toThrow(
       new ScalewayError(
         validResponse.status,
@@ -104,30 +116,42 @@ describe(`responseParser`, () => {
       responseParser(() => {
         // eslint-disable-next-line @typescript-eslint/no-throw-literal
         throw 'not-of-error-type'
-      })(validResponse.clone()),
+      }, 'text')(validResponse.clone()),
     ).rejects.toThrow(
       new ScalewayError(
         validResponse.status,
         `could not parse 'application/json' response`,
       ),
     )
-  })
 
-  it(`returns the response as-if for unknown content type`, async () => {
-    const textResponse = makeValidTextResponse('text-body')
-
-    return expect(parseAsIs(textResponse)).resolves.toBe('text-body')
+    await expect(
+      responseParser(() => {
+        // eslint-disable-next-line @typescript-eslint/no-throw-literal
+        throw 'not-of-error-type'
+      }, 'blob')(emptyContentTypeResponse),
+    ).rejects.toThrow(
+      new ScalewayError(
+        emptyContentTypeResponse.status,
+        `could not parse '' response`,
+      ),
+    )
   })
 
-  it(`returns a simple object for a valid 'Response' object`, async () =>
-    expect(parseJson(makeValidJSONResponse())).resolves.toMatchObject(
+  it(`returns the response as text for unknown content type`, async () =>
+    expect(parseAsIs(makeTextResponse('text-body'))).resolves.toBe('text-body'))
+
+  it(`returns the proper object for a valid JSON object`, async () =>
+    expect(parseJson(makeJSONResponse())).resolves.toMatchObject(
       SIMPLE_REQ_BODY,
     ))
 
-  it(`returns undefined for a 204 status code, even if content-type is json`, async () =>
+  it(`returns the proper type for a Blob responseType`, async () =>
     expect(
-      parseAsIs(makeValidJSONResponse(null, 204)),
-    ).resolves.toBeUndefined())
+      parseBlob(makeTextResponse('hello world')).then(obj => typeof obj),
+    ).resolves.toBe('object'))
+
+  it(`returns undefined for a 204 status code, even if content-type is json`, async () =>
+    expect(parseAsIs(makeJSONResponse(null, 204))).resolves.toBeUndefined())
 })
 
 describe('fixLegacyTotalCount', () => {

packages/clients/src/scw/fetch/build-fetcher.ts

@@ -78,6 +78,6 @@ export const buildFetcher = (settings: Settings, httpClient: typeof fetch) => {
       .then(prepareRequest(requestId))
       .then(httpClient)
       .then(prepareResponse(requestId))
-      .then(responseParser<T>(unwrapper))
+      .then(responseParser<T>(unwrapper, request.responseType ?? 'json'))
   }
 }

packages/clients/src/scw/fetch/response-parser.ts

@@ -45,7 +45,10 @@ export const fixLegacyTotalCount = <T>(obj: T, headers: Headers): T => {
  * @internal
  */
 export const responseParser =
-  <T>(unmarshaller: ResponseUnmarshaller<T>) =>
+  <T>(
+    unmarshaller: ResponseUnmarshaller<T>,
+    responseType: 'json' | 'text' | 'blob',
+  ) =>
   async (response: Response): Promise<T> => {
     if (!(response instanceof Response))
       throw new TypeError('Invalid response object')
@@ -54,14 +57,16 @@ export const responseParser =
       if (response.status === 204) return unmarshaller(undefined)
       const contentType = response.headers.get('Content-Type')
       try {
-        switch (contentType) {
-          case 'application/json':
-            return unmarshaller(
-              fixLegacyTotalCount(await response.json(), response.headers),
-            )
-          default:
-            return unmarshaller(await response.text())
+        if (responseType === 'json' && contentType === 'application/json') {
+          return unmarshaller(
+            fixLegacyTotalCount(await response.json(), response.headers),
+          )
         }
+        if (responseType === 'blob') {
+          return unmarshaller(await response.blob())
+        }
+
+        return unmarshaller(await response.text())
       } catch (err) {
         throw new ScalewayError(
           response.status,

packages/clients/src/scw/fetch/types.ts

@@ -5,6 +5,7 @@ export type ScwRequest = {
   headers?: Record<string, string>
   body?: string
   urlParams?: URLSearchParams
+  responseType?: 'json' | 'text' | 'blob'
 }
 
 /**