what is promise async and await code example

Example 1: async await

async function showAvatar() {

  // read our JSON
  let response = await fetch('/article/promise-chaining/user.json');
  let user = await response.json();

  // read github user
  let githubResponse = await fetch(`https://api.github.com/users/${user.name}`);
  let githubUser = await githubResponse.json();

  // show the avatar
  let img = document.createElement('img');
  img.src = githubUser.avatar_url;
  img.className = "promise-avatar-example";
  document.body.append(img);

  // wait 3 seconds
  await new Promise((resolve, reject) => setTimeout(resolve, 3000));

  img.remove();

  return githubUser;
}

showAvatar();

Example 2: nodejs promise async

// server.js
 
function square(x) {
  return new Promise(resolve => {
    setTimeout(() => {
      resolve(Math.pow(x, 2));
    }, 2000);
  });
}
 
async function layer(x)
{
  const value = await square(x);
  console.log(value);
}
 
layer(10);