fix(signal): cancel status-only response bodies

extensions/signal/src/client-container.test.ts

@@ -130,6 +130,22 @@ describe("containerCheck", () => {
     expectFirstFetchCall("http://localhost:8080/v1/about", "GET");
   });
 
+  it("cancels /v1/about response bodies after simple health checks", async () => {
+    const cancel = vi.fn(async () => undefined);
+    mockFetch.mockResolvedValue({
+      ok: true,
+      status: 200,
+      body: { cancel },
+    });
+
+    await expect(containerCheck("http://localhost:8080")).resolves.toEqual({
+      ok: true,
+      status: 200,
+      error: null,
+    });
+    expect(cancel).toHaveBeenCalledTimes(1);
+  });
+
   it("returns ok:false when /v1/about returns 404", async () => {
     mockFetch.mockResolvedValue({
       ok: false,
@@ -635,9 +651,11 @@ describe("containerFetchAttachment", () => {
   });
 
   it("returns null on non-ok response", async () => {
+    const cancel = vi.fn(async () => undefined);
     mockFetch.mockResolvedValue({
       ok: false,
       status: 404,
+      body: { cancel },
     });
 
     const result = await containerFetchAttachment("attachment-123", {
@@ -645,6 +663,7 @@ describe("containerFetchAttachment", () => {
     });
 
     expect(result).toBeNull();
+    expect(cancel).toHaveBeenCalledTimes(1);
   });
 
   it("encodes attachment ID in URL", async () => {

extensions/signal/src/client-container.ts

@@ -111,6 +111,12 @@ async function readCappedResponseBuffer(res: Response, maxResponseBytes: number)
   });
 }
 
+async function releaseUnreadResponseBody(res: Response | undefined): Promise<void> {
+  if (res?.bodyUsed !== true) {
+    await res?.body?.cancel().catch(() => undefined);
+  }
+}
+
 /**
  * Check if bbernhard container REST API is available.
  */
@@ -120,8 +126,9 @@ export async function containerCheck(
   account?: string,
 ): Promise<{ ok: boolean; status?: number | null; error?: string | null }> {
   const normalized = normalizeBaseUrl(baseUrl);
+  let res: Response | undefined;
   try {
-    const res = await fetchWithTimeout(`${normalized}/v1/about`, { method: "GET" }, timeoutMs);
+    res = await fetchWithTimeout(`${normalized}/v1/about`, { method: "GET" }, timeoutMs);
     if (!res.ok) {
       return { ok: false, status: res.status, error: `HTTP ${res.status}` };
     }
@@ -136,6 +143,8 @@ export async function containerCheck(
       status: null,
       error: err instanceof Error ? err.message : String(err),
     };
+  } finally {
+    await releaseUnreadResponseBody(res);
   }
 }
 
@@ -253,14 +262,19 @@ export async function containerFetchAttachment(
 ): Promise<Buffer | null> {
   const baseUrl = normalizeBaseUrl(opts.baseUrl);
   const url = `${baseUrl}/v1/attachments/${encodeURIComponent(attachmentId)}`;
+  let res: Response | undefined;
 
-  const res = await fetchWithTimeout(url, { method: "GET" }, opts.timeoutMs ?? DEFAULT_TIMEOUT_MS);
+  try {
+    res = await fetchWithTimeout(url, { method: "GET" }, opts.timeoutMs ?? DEFAULT_TIMEOUT_MS);
 
-  if (!res.ok) {
-    return null;
+    if (!res.ok) {
+      return null;
+    }
+
+    return await readCappedResponseBuffer(res, normalizeMaxResponseBytes(opts.maxResponseBytes));
+  } finally {
+    await releaseUnreadResponseBody(res);
   }
-
-  return readCappedResponseBuffer(res, normalizeMaxResponseBytes(opts.maxResponseBytes));
 }
 
 /**