chore(internal): refactor sse event parsing

Author: stainless-app[bot]

src/core/streaming.ts

@@ -35,6 +35,7 @@ export class Stream<Item> implements AsyncIterable<Item> {
     response: Response,
     controller: AbortController,
     client?: OpenAI,
+    synthesizeEventData?: boolean,
   ): Stream<Item> {
     let consumed = false;
     const logger = client ? loggerFor(client) : console;
@@ -69,7 +70,7 @@ export class Stream<Item> implements AsyncIterable<Item> {
               throw new APIError(undefined, data.error, undefined, response.headers);
             }
 
-            yield data;
+            yield synthesizeEventData ? { event: sse.event, data } : data;
           } else {
             let data;
             try {

src/internal/parse.ts

@@ -28,10 +28,20 @@ export async function defaultParseResponse<T>(
       // that if you set `stream: true` the response type must also be `Stream<T>`
 
       if (props.options.__streamClass) {
-        return props.options.__streamClass.fromSSEResponse(response, props.controller, client) as any;
+        return props.options.__streamClass.fromSSEResponse(
+          response,
+          props.controller,
+          client,
+          props.options.__synthesizeEventData,
+        ) as any;
       }
 
-      return Stream.fromSSEResponse(response, props.controller, client) as any;
+      return Stream.fromSSEResponse(
+        response,
+        props.controller,
+        client,
+        props.options.__synthesizeEventData,
+      ) as any;
     }
 
     // fetch refuses to read the body when the status code is 204.

src/internal/request-options.ts

@@ -79,6 +79,7 @@ export type RequestOptions = {
   __metadata?: Record<string, unknown>;
   __binaryResponse?: boolean | undefined;
   __streamClass?: typeof Stream;
+  __synthesizeEventData?: boolean;
 };
 
 export type EncodedContent = { bodyHeaders: HeadersLike; body: BodyInit };

src/resources/beta/threads/runs/runs.ts

@@ -75,6 +75,7 @@ export class Runs extends APIResource {
       ...options,
       headers: buildHeaders([{ 'OpenAI-Beta': 'assistants=v2' }, options?.headers]),
       stream: params.stream ?? false,
+      __synthesizeEventData: true,
     }) as APIPromise<Run> | APIPromise<Stream<AssistantsAPI.AssistantStreamEvent>>;
   }
 
@@ -259,6 +260,7 @@ export class Runs extends APIResource {
       ...options,
       headers: buildHeaders([{ 'OpenAI-Beta': 'assistants=v2' }, options?.headers]),
       stream: params.stream ?? false,
+      __synthesizeEventData: true,
     }) as APIPromise<Run> | APIPromise<Stream<AssistantsAPI.AssistantStreamEvent>>;
   }
 

src/resources/beta/threads/threads.ts

@@ -152,6 +152,7 @@ export class Threads extends APIResource {
       ...options,
       headers: buildHeaders([{ 'OpenAI-Beta': 'assistants=v2' }, options?.headers]),
       stream: body.stream ?? false,
+      __synthesizeEventData: true,
     }) as APIPromise<RunsAPI.Run> | APIPromise<Stream<AssistantsAPI.AssistantStreamEvent>>;
   }