Wrapper for sending requests 1 by 1

syncRequests.js

/*
  @Params: 
    action: Promise
*/
const syncRequests = function(action) {
  let req = null;
  let requestInProcess = false;

  return (...params) => {
    if (requestInProcess) {
      return req;
    }

    req = action(...params);
    requestInProcess = true;

    req.finally(() => {
      requestInProcess = false;
    });

    return req;
  };
};

const fetchData = () => axios.get('/posts');
const syncFetchData = syncRequests(fetchData);

setInterval(() => {
  syncFetchData();
}, 1)

/*
  Requests to network will only land 1 by 1. 
  So there is never will be 2 parallel network requests hanging.
*/