async-iterators-example.js

async-iterators-example.js

/**
 * Async iterators simple example.
 *
 * by Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
 * MIT Style License, 2018
 */

async function* streamChunks() {
  yield genChunk(1);
  yield genChunk(2);
  yield genChunk(3);
}

async function genChunk(v) {
  const ms = v * 1000;
  console.log(`Wating for ${ms} ms...`);
  await sleep(ms);
  return v;
}

async function sleep(ms) {
  return new Promise(resolve => setTimeout(resolve, ms));
}

const genChunks = async () => {
  for await (const chunk of streamChunks()) {
    console.log(`  - Received chunk: ${chunk}\n`);
  }
  console.log('Request finished.');
};

genChunks();

/*

Results:

Wating for 1000 ms...
  - Received chunk: 1

Wating for 2000 ms...
  - Received chunk: 2

Wating for 3000 ms...
  - Received chunk: 3

Request finished.

*/