Execute batch of promises in series. Once Promise.all is done go to the next batch

Question

I have an array that contains an array of promises, and each inner array could have either 4k, 2k or 500 promises.

In total there are around 60k promises and I may test

Answer 1

You can do it recursively, for example here I needed to put about 60k documents in mongo, but it was too big, to do it in one step, therefore I take 1k documents, send them to the mongo, after it is finished I take another 1k documents etc.

exports.rawRecursive = (arr, start) => {
        //ending condition
        if (start > arr.length) {
            return;
        }

        Rawmedicament.insertManyAsync(_.slice(arr, start, start + 1000)).then(() => {
            //recursive
            exports.rawRecursive(arr, start + 1000);
        });
};

If you want to notice, when everything is done, you can in ending condition put callback or if you like Promises you can call resolve() there.