hanlde upload progress with saga and axios

Question

i am trying to make a progress bar in react.and after i upload file i get this error: Error: call: argument of type {context, fn} has undefined or null fn

saga.js:

const identity = a => a;

const createAsync = file => {
  let emit;
  const chan = eventChannel(emitter => {
    emit = emitter;
    return () => {};
  });
  const promise = uploadVideoApi(file, function(e) {
    emit((e.loaded * 100) / e.total);
  });

  return [promise, chan];
};

function* watchOnProgress(chan) {
  while (true) {
    const data = yield take(chan);
    yield put(uploadFileProgress(data));
  }
}

function* uploadVideo({ file }) {
  const [promise, chan] = createAsync(file);
  yield fork(watchOnProgress, chan);
  const result = yield call(identity(promise));
}

actions.js:

export function uploadFileProgress(percent) {
  return {
    type: UPLOAD_VIDEO_PROGRESS,
    percent,
  };
}