setIntervalAsync.js

console.clear();

var intervalIds = {
    nextId: 1,
};

/**
 * Invoke a function callback on an interval delay. This is better than setInterval, as it...
 * 1. Waits for the function to complete before starting the next interval
 * 2. Waits for the optional returned Promise to resolve before starting the next interval
 *
 * @param {Function} fn A callback function to be executed every delay milliseconds.
 * If a Promise is returned from the callback function, then wait for the Promise to resolve
 * @param {number} delay Interval delay in milliseconds. See
 * {@link https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/setTimeout|setTimeout}
 * for more details about the delay value
 * @returns {number} The returned timer id is a non-zero value which identifies the timer created
 * by setIntervalAsync; this value can be passed to clearIntervalAsync to clear the interval
 */
function setIntervalAsync(fn, delay) {
    var timerId = arguments[2];
    if (timerId === undefined) {
        timerId = intervalIds.nextId;
        intervalIds.nextId += 1;
    }

    new Promise(function (resolve) {
        resolve(fn());
    })
    .then(function () {
        if (intervalIds[timerId] !== 0) {
            intervalIds[timerId] = setTimeout(function () {
                setIntervalAsync(fn, delay, timerId);
            }, delay);
        }
    })
    .catch(function (err) {
        // Stop the interval on fatal error
        console.error('setIntervalAsync::', err);
    });

    return timerId;
}

/**
 * Clear the timer interval created by setIntervalAsync
 *
 * @param {number} timerId Timer id to clear
 * @returns {void}
 */
function clearIntervalAsync(timerId) {
    clearTimeout(intervalIds[timerId]);
    intervalIds[timerId] = 0;
}

// Example(s)
setIntervalAsync(function () {
    console.log('Interval:', Date.now());

    // Delay the resolution of the Promise
    return new Promise(function (resolve) {
        setTimeout(resolve, 1000);
    });
}, 0);

// Shows how to cancel the interval
var id = 0;
var timerId = setIntervalAsync(function () {
    console.log('Id:', id);

    id += 1;
}, 0);

// Clear after 20ms
setTimeout(function () {
    clearIntervalAsync(timerId);
}, 20);