Merge pull request #1507 from nimobeeren/fix/dont-parse-without-conte…

…nt-type

.changeset/wise-poets-flow.md

@@ -0,0 +1,5 @@
+---
+'@hey-api/client-fetch': minor
+---
+
+[BREAKING] return raw response body (of type `ReadableStream`) when `Content-Type` response header is not provided and `parseAs` is set to `auto`

packages/client-fetch/src/__tests__/utils.test.ts

@@ -77,7 +77,7 @@ describe('getParseAs', () => {
   }> = [
     {
       content: null,
-      parseAs: undefined,
+      parseAs: 'stream',
     },
     {
       content: 'application/json',

packages/client-fetch/src/index.ts

@@ -93,18 +93,18 @@ export const createClient = (config: Config = {}): Client => {
         };
       }
 
-      if (opts.parseAs === 'stream') {
+      const parseAs =
+        (opts.parseAs === 'auto'
+          ? getParseAs(response.headers.get('Content-Type'))
+          : opts.parseAs) ?? 'json';
+
+      if (parseAs === 'stream') {
         return {
           data: response.body,
           ...result,
         };
       }
 
-      const parseAs =
-        (opts.parseAs === 'auto'
-          ? getParseAs(response.headers.get('Content-Type'))
-          : opts.parseAs) ?? 'json';
-
       let data = await response[parseAs]();
       if (parseAs === 'json') {
         if (opts.responseValidator) {

packages/client-fetch/src/utils.ts

@@ -327,9 +327,11 @@ export const createQuerySerializer = <T = unknown>({
  */
 export const getParseAs = (
   contentType: string | null,
-): Exclude<Config['parseAs'], 'auto' | 'stream'> => {
+): Exclude<Config['parseAs'], 'auto'> => {
   if (!contentType) {
-    return;
+    // If no Content-Type header is provided, the best we can do is return the raw response body,
+    // which is effectively the same as the 'stream' option.
+    return 'stream';
   }
 
   const cleanContent = contentType.split(';')[0]?.trim();