Function restStorage

packages/react-headless/src/adapters/restStorage.ts:33–89

({
  baseUrl,
  messageFormat = identityMessageFormat,
  headers,
  fetch: customFetch,
}: RestStorageOptions)

 * (e.g. `fetchLLM`).
 */
export function restStorage({
  baseUrl,
  messageFormat = identityMessageFormat,
  headers,
  fetch: customFetch,
}: RestStorageOptions): ChatStorage {
  const fetchImpl = customFetch ?? globalThis.fetch.bind(globalThis);

  const request = async (url: string, init?: RequestInit): Promise<Response> => {
    const res = await fetchImpl(url, {
      ...init,
      headers: {
        ...(init?.body ? { "Content-Type": "application/json" } : {}),
        ...headers,
        ...init?.headers,
      },
    });
    if (!res.ok) {
      throw new Error(
        `restStorage: ${init?.method ?? "GET"} ${url} failed: ${res.status} ${res.statusText}`,
      );
    }
    return res;
  };

  return {
    thread: {
      async listThreads(cursor?: string) {
        const url = cursor ? `${baseUrl}/get?cursor=${cursor}` : `${baseUrl}/get`;
        const res = await request(url);
        return res.json();
      },
      async createThread(firstMessage: UserMessage): Promise<Thread> {
        const res = await request(`${baseUrl}/create`, {
          method: "POST",
          body: JSON.stringify({ messages: messageFormat.toApi([firstMessage]) }),
        });
        return res.json();
      },
      async getMessages(threadId: string): Promise<Message[]> {
        const res = await request(`${baseUrl}/get/${threadId}`);
        const raw: unknown = await res.json();
        return messageFormat.fromApi(raw);
      },
      async updateThread(thread: Thread): Promise<Thread> {
        const res = await request(`${baseUrl}/update/${thread.id}`, {
          method: "PATCH",
          body: JSON.stringify(thread),
        });
        return res.json();
      },
      async deleteThread(id: string): Promise<void> {
        await request(`${baseUrl}/delete/${id}`, { method: "DELETE" });
      },
    },
  };
}