fix: surface HTTP errors when using http requests

Author: ranst91

typescript-sdk/packages/client/src/run/__tests__/http-request.test.ts

@@ -192,4 +192,53 @@ describe("runHttpRequest", () => {
     // Clean up
     subscription.unsubscribe();
   });
+
+  it("should throw HTTP error on occurs", async () => {
+    // Mock a 404 error response with JSON body
+    const mockHeaders = new Headers();
+    mockHeaders.append("content-type", "application/json");
+
+    const mockText = '{"message":"User not found"}';
+
+    const mockResponse = {
+      ok: false,
+      status: 404,
+      headers: mockHeaders,
+      // our error-path reads .text() (not streaming)
+      text: jest.fn().mockResolvedValue(mockText),
+    } as unknown as Response;
+
+    // Override fetch for this test
+    fetchMock.mockResolvedValue(mockResponse);
+
+    const observable = runHttpRequest("https://example.com/api", { method: "GET" });
+
+    const nextSpy = jest.fn();
+
+    await new Promise<void>((resolve) => {
+      const sub = observable.subscribe({
+        next: nextSpy,
+        error: (err: any) => {
+          // error should carry status + parsed payload
+          expect(err).toBeInstanceOf(Error);
+          expect(err.status).toBe(404);
+          expect(err.payload).toEqual({ message: "User not found" });
+          // readable message is okay too (optional)
+          expect(err.message).toContain("HTTP 404");
+          expect(err.message).toContain("User not found");
+          resolve();
+          sub.unsubscribe();
+        },
+        complete: () => {
+          fail("Should not complete on HTTP error");
+        },
+      });
+    });
+
+    // Should not have emitted any data events on error short-circuit
+    expect(nextSpy).not.toHaveBeenCalled();
+
+    // Ensure we read the error body exactly once
+    expect((mockResponse as any).text).toHaveBeenCalledTimes(1);
+  });
 });

typescript-sdk/packages/client/src/run/http-request.ts

@@ -1,5 +1,5 @@
 import { Observable, from, defer, throwError } from "rxjs";
-import { switchMap } from "rxjs/operators";
+import { mergeMap, switchMap } from "rxjs/operators";
 
 export enum HttpEventType {
   HEADERS = "headers",
@@ -23,6 +23,24 @@ export const runHttpRequest = (url: string, requestInit: RequestInit): Observabl
   // Defer the fetch so that it's executed when subscribed to
   return defer(() => from(fetch(url, requestInit))).pipe(
     switchMap((response) => {
+      if (!response.ok) {
+        const contentType = response.headers.get("content-type") || "";
+        // Read the (small) error body once, then error the stream
+        return from(response.text()).pipe(
+          mergeMap((text) => {
+            let payload: unknown = text;
+            if (contentType.includes("application/json")) {
+              try { payload = JSON.parse(text); } catch {/* keep raw text */}
+            }
+            const err: any = new Error(
+              `HTTP ${response.status}: ${typeof payload === "string" ? payload : JSON.stringify(payload)}`
+            );
+            err.status = response.status;
+            err.payload = payload;
+            return throwError(() => err);
+          })
+        );
+      }
       // Emit headers event first
       const headersEvent: HttpHeadersEvent = {
         type: HttpEventType.HEADERS,