async-await-queue-basic-example.js

const Queue = require('async-await-queue');
/**
 * No more than 10 parallel, spaced at least 100ms apart
 * These are typical fair-use limitations of public APIs
 **/
const queue = new Queue(10, 100);
let p = [];
for (let url of urls) {
    /* Generate a queue ID */
    const me = Symbol();
    /* 0 is the priority, -1 is higher priority than 0 */
    p.push(queue.wait(me, 0)
        .then(() => download(url))
        .then((html) => {
            data[url] = parse(html);
        })
        .catch((e) => console.error(e))
        /* don't forget this or you will end up freezing */
        .finally(() => queue.end(me)));
}
await Promise.allSettled(p);