promise all.js

// simulate async operation
function fetchMockData(name, timeToWait = 2000) {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve({ name: name });
    }, timeToWait);
  });
}
const allPromises = [fetchMockData('John'), fetchMockData('Peter')];
Promise.all(allPromises)
  .then((results) => {
    const [first, second] = results;
    console.log(first, second);
  })
  .catch((err) => {
    console.log(err);
  });