proto-over-http

proto-over-http.ts

function doFetch<ReqT extends { serializeBinary(): Uint8Array }, RespT>
  (method: string, req: ReqT, respClass: { new(): RespT, deserializeBinary(bytes: Uint8Array): RespT }): Promise<RespT> {
  const params: RequestInit = {
    headers: {
      "Accept": PROTO_CONTENT_TYPE,
      "Content-Type": PROTO_CONTENT_TYPE,
    },
    method: "POST",
    body: toArrayBuffer(req.serializeBinary()),
  };

  return fetch(`${API_ENDPOINT}/${method}`, params).then((res) => {
    if (!res.ok) {
      throw Error(res.statusText);
    }
    return res.arrayBuffer().then((buffer) => respClass.deserializeBinary(new Uint8Array(buffer)));
  });
}

function toArrayBuffer(encodedRequest: Uint8Array): ArrayBuffer {
  return encodedRequest.buffer.slice(encodedRequest.byteOffset, encodedRequest.byteOffset + encodedRequest.byteLength);
}