Javascript get callback from function within map

Question

I have been struggling with this for quite sometime and haven't been able to find a good solution for this problem.

I have an array which I map through an imported function that has a call back. I want to get the data(JSON) from the callback, manipulate it, output it and run it through another function.

Because the node_module qbo.getBill function has a callback, I don't think I can run promise or async\\await, well I haven't had any success doing so as soon as I add the getBill function.

Here is my code/what I am trying to do:

 var QuickBooks = require('node-quickbooks') var qbo = new QuickBooks(...) let BillIds = [....] let newArray =[] let mapData = BillIds.map(val => { qbo.getBill(val, function (err, Billid) { newArray.push = { id: Billid.Id, balance: Billid.Balance } }) }) DoAThingWithAsyncronousData(newArray) 

For the life of me I can't get any action to wait on the the asynchronous data before completing the next step, where am I going wrong?

Answer 1

Sure you can use Promise.all, you just need to put a promise around getBill 's callback:

const newArray = await Promise.all(
  BillIds.map(val => new Promise((resolve, reject) => {
    qbo.getBill(val, (err, Billid) => {
      const billObj = {
        id: Billid.Id,
        balance: Billid.Balance
      }
      resolve(billObj)
    });
  }))
);

DoAThingWithAsyncronousData(newArray)