refactor: share googlechat api fetch handling

extensions/googlechat/src/api.test.ts

@@ -13,6 +13,21 @@ const account = {
   config: {},
 } as ResolvedGoogleChatAccount;
 
+function stubSuccessfulSend(name: string) {
+  const fetchMock = vi
+    .fn()
+    .mockResolvedValue(new Response(JSON.stringify({ name }), { status: 200 }));
+  vi.stubGlobal("fetch", fetchMock);
+  return fetchMock;
+}
+
+async function expectDownloadToRejectForResponse(response: Response) {
+  vi.stubGlobal("fetch", vi.fn().mockResolvedValue(response));
+  await expect(
+    downloadGoogleChatMedia({ account, resourceName: "media/123", maxBytes: 10 }),
+  ).rejects.toThrow(/max bytes/i);
+}
+
 describe("downloadGoogleChatMedia", () => {
   afterEach(() => {
     vi.unstubAllGlobals();
@@ -29,11 +44,7 @@ describe("downloadGoogleChatMedia", () => {
       status: 200,
       headers: { "content-length": "50", "content-type": "application/octet-stream" },
     });
-    vi.stubGlobal("fetch", vi.fn().mockResolvedValue(response));
-
-    await expect(
-      downloadGoogleChatMedia({ account, resourceName: "media/123", maxBytes: 10 }),
-    ).rejects.toThrow(/max bytes/i);
+    await expectDownloadToRejectForResponse(response);
   });
 
   it("rejects when streamed payload exceeds max bytes", async () => {
@@ -52,11 +63,7 @@ describe("downloadGoogleChatMedia", () => {
       status: 200,
       headers: { "content-type": "application/octet-stream" },
     });
-    vi.stubGlobal("fetch", vi.fn().mockResolvedValue(response));
-
-    await expect(
-      downloadGoogleChatMedia({ account, resourceName: "media/123", maxBytes: 10 }),
-    ).rejects.toThrow(/max bytes/i);
+    await expectDownloadToRejectForResponse(response);
   });
 });
 
@@ -66,12 +73,7 @@ describe("sendGoogleChatMessage", () => {
   });
 
   it("adds messageReplyOption when sending to an existing thread", async () => {
-    const fetchMock = vi
-      .fn()
-      .mockResolvedValue(
-        new Response(JSON.stringify({ name: "spaces/AAA/messages/123" }), { status: 200 }),
-      );
-    vi.stubGlobal("fetch", fetchMock);
+    const fetchMock = stubSuccessfulSend("spaces/AAA/messages/123");
 
     await sendGoogleChatMessage({
       account,
@@ -89,12 +91,7 @@ describe("sendGoogleChatMessage", () => {
   });
 
   it("does not set messageReplyOption for non-thread sends", async () => {
-    const fetchMock = vi
-      .fn()
-      .mockResolvedValue(
-        new Response(JSON.stringify({ name: "spaces/AAA/messages/124" }), { status: 200 }),
-      );
-    vi.stubGlobal("fetch", fetchMock);
+    const fetchMock = stubSuccessfulSend("spaces/AAA/messages/124");
 
     await sendGoogleChatMessage({
       account,

extensions/googlechat/src/api.ts

@@ -14,70 +14,24 @@ const headersToObject = (headers?: HeadersInit): Record<string, string> =>
       ? Object.fromEntries(headers)
       : headers || {};
 
-async function fetchJson<T>(
-  account: ResolvedGoogleChatAccount,
-  url: string,
-  init: RequestInit,
-): Promise<T> {
-  const token = await getGoogleChatAccessToken(account);
-  const { response: res, release } = await fetchWithSsrFGuard({
+async function withGoogleChatResponse<T>(params: {
+  account: ResolvedGoogleChatAccount;
+  url: string;
+  init?: RequestInit;
+  auditContext: string;
+  errorPrefix?: string;
+  handleResponse: (response: Response) => Promise<T>;
+}): Promise<T> {
+  const {
+    account,
     url,
-    init: {
-      ...init,
-      headers: {
-        ...headersToObject(init.headers),
-        Authorization: `Bearer ${token}`,
-        "Content-Type": "application/json",
-      },
-    },
-    auditContext: "googlechat.api.json",
-  });
-  try {
-    if (!res.ok) {
-      const text = await res.text().catch(() => "");
-      throw new Error(`Google Chat API ${res.status}: ${text || res.statusText}`);
-    }
-    return (await res.json()) as T;
-  } finally {
-    await release();
-  }
-}
-
-async function fetchOk(
-  account: ResolvedGoogleChatAccount,
-  url: string,
-  init: RequestInit,
-): Promise<void> {
+    init,
+    auditContext,
+    errorPrefix = "Google Chat API",
+    handleResponse,
+  } = params;
   const token = await getGoogleChatAccessToken(account);
-  const { response: res, release } = await fetchWithSsrFGuard({
-    url,
-    init: {
-      ...init,
-      headers: {
-        ...headersToObject(init.headers),
-        Authorization: `Bearer ${token}`,
-      },
-    },
-    auditContext: "googlechat.api.ok",
-  });
-  try {
-    if (!res.ok) {
-      const text = await res.text().catch(() => "");
-      throw new Error(`Google Chat API ${res.status}: ${text || res.statusText}`);
-    }
-  } finally {
-    await release();
-  }
-}
-
-async function fetchBuffer(
-  account: ResolvedGoogleChatAccount,
-  url: string,
-  init?: RequestInit,
-  options?: { maxBytes?: number },
-): Promise<{ buffer: Buffer; contentType?: string }> {
-  const token = await getGoogleChatAccessToken(account);
-  const { response: res, release } = await fetchWithSsrFGuard({
+  const { response, release } = await fetchWithSsrFGuard({
     url,
     init: {
       ...init,
@@ -86,52 +40,103 @@ async function fetchBuffer(
         Authorization: `Bearer ${token}`,
       },
     },
-    auditContext: "googlechat.api.buffer",
+    auditContext,
   });
   try {
-    if (!res.ok) {
-      const text = await res.text().catch(() => "");
-      throw new Error(`Google Chat API ${res.status}: ${text || res.statusText}`);
+    if (!response.ok) {
+      const text = await response.text().catch(() => "");
+      throw new Error(`${errorPrefix} ${response.status}: ${text || response.statusText}`);
     }
-    const maxBytes = options?.maxBytes;
-    const lengthHeader = res.headers.get("content-length");
-    if (maxBytes && lengthHeader) {
-      const length = Number(lengthHeader);
-      if (Number.isFinite(length) && length > maxBytes) {
-        throw new Error(`Google Chat media exceeds max bytes (${maxBytes})`);
-      }
-    }
-    if (!maxBytes || !res.body) {
-      const buffer = Buffer.from(await res.arrayBuffer());
-      const contentType = res.headers.get("content-type") ?? undefined;
-      return { buffer, contentType };
-    }
-    const reader = res.body.getReader();
-    const chunks: Buffer[] = [];
-    let total = 0;
-    while (true) {
-      const { done, value } = await reader.read();
-      if (done) {
-        break;
-      }
-      if (!value) {
-        continue;
-      }
-      total += value.length;
-      if (total > maxBytes) {
-        await reader.cancel();
-        throw new Error(`Google Chat media exceeds max bytes (${maxBytes})`);
-      }
-      chunks.push(Buffer.from(value));
-    }
-    const buffer = Buffer.concat(chunks, total);
-    const contentType = res.headers.get("content-type") ?? undefined;
-    return { buffer, contentType };
+    return await handleResponse(response);
   } finally {
     await release();
   }
 }
 
+async function fetchJson<T>(
+  account: ResolvedGoogleChatAccount,
+  url: string,
+  init: RequestInit,
+): Promise<T> {
+  return await withGoogleChatResponse({
+    account,
+    url,
+    init: {
+      ...init,
+      headers: {
+        ...headersToObject(init.headers),
+        "Content-Type": "application/json",
+      },
+    },
+    auditContext: "googlechat.api.json",
+    handleResponse: async (response) => (await response.json()) as T,
+  });
+}
+
+async function fetchOk(
+  account: ResolvedGoogleChatAccount,
+  url: string,
+  init: RequestInit,
+): Promise<void> {
+  await withGoogleChatResponse({
+    account,
+    url,
+    init,
+    auditContext: "googlechat.api.ok",
+    handleResponse: async () => undefined,
+  });
+}
+
+async function fetchBuffer(
+  account: ResolvedGoogleChatAccount,
+  url: string,
+  init?: RequestInit,
+  options?: { maxBytes?: number },
+): Promise<{ buffer: Buffer; contentType?: string }> {
+  return await withGoogleChatResponse({
+    account,
+    url,
+    init,
+    auditContext: "googlechat.api.buffer",
+    handleResponse: async (res) => {
+      const maxBytes = options?.maxBytes;
+      const lengthHeader = res.headers.get("content-length");
+      if (maxBytes && lengthHeader) {
+        const length = Number(lengthHeader);
+        if (Number.isFinite(length) && length > maxBytes) {
+          throw new Error(`Google Chat media exceeds max bytes (${maxBytes})`);
+        }
+      }
+      if (!maxBytes || !res.body) {
+        const buffer = Buffer.from(await res.arrayBuffer());
+        const contentType = res.headers.get("content-type") ?? undefined;
+        return { buffer, contentType };
+      }
+      const reader = res.body.getReader();
+      const chunks: Buffer[] = [];
+      let total = 0;
+      while (true) {
+        const { done, value } = await reader.read();
+        if (done) {
+          break;
+        }
+        if (!value) {
+          continue;
+        }
+        total += value.length;
+        if (total > maxBytes) {
+          await reader.cancel();
+          throw new Error(`Google Chat media exceeds max bytes (${maxBytes})`);
+        }
+        chunks.push(Buffer.from(value));
+      }
+      const buffer = Buffer.concat(chunks, total);
+      const contentType = res.headers.get("content-type") ?? undefined;
+      return { buffer, contentType };
+    },
+  });
+}
+
 export async function sendGoogleChatMessage(params: {
   account: ResolvedGoogleChatAccount;
   space: string;
@@ -208,34 +213,29 @@ export async function uploadGoogleChatAttachment(params: {
     Buffer.from(footer, "utf8"),
   ]);
 
-  const token = await getGoogleChatAccessToken(account);
   const url = `${CHAT_UPLOAD_BASE}/${space}/attachments:upload?uploadType=multipart`;
-  const { response: res, release } = await fetchWithSsrFGuard({
+  const payload = await withGoogleChatResponse<{
+    attachmentDataRef?: { attachmentUploadToken?: string };
+  }>({
+    account,
     url,
     init: {
       method: "POST",
       headers: {
-        Authorization: `Bearer ${token}`,
         "Content-Type": `multipart/related; boundary=${boundary}`,
       },
       body,
     },
     auditContext: "googlechat.upload",
+    errorPrefix: "Google Chat upload",
+    handleResponse: async (response) =>
+      (await response.json()) as {
+        attachmentDataRef?: { attachmentUploadToken?: string };
+      },
   });
-  try {
-    if (!res.ok) {
-      const text = await res.text().catch(() => "");
-      throw new Error(`Google Chat upload ${res.status}: ${text || res.statusText}`);
-    }
-    const payload = (await res.json()) as {
-      attachmentDataRef?: { attachmentUploadToken?: string };
-    };
-    return {
-      attachmentUploadToken: payload.attachmentDataRef?.attachmentUploadToken,
-    };
-  } finally {
-    await release();
-  }
+  return {
+    attachmentUploadToken: payload.attachmentDataRef?.attachmentUploadToken,
+  };
 }
 
 export async function downloadGoogleChatMedia(params: {