How to iterate over account history items

Using steem.js, it is easy to iterate over all the history items of an account. However, if you have not done this before, it may be a little tricky, because there is not enough documentation on the web (or maybe I didn’t find it).

Anyway, steem.api.getAccountHistory returns a promise that resolves to a batch of history items. Each item has an ID number (that starts with 1 for the first item in the history). The batch returned is sorted ascendingly, and contains limit + 1 items, starting at from. If you want to start at the most recent item, you can give from a value of -1. Otherwise, from must be larger than or equal to limit.

Here is an example code for getting history items:

    for (let from = -1, limit = 100, going = true; !!from && going; ) {
        let items = await steem.api.getAccountHistory(username, from, Math.min(limit, from));
        from = items[0][0] - 1;
        items.reverse();
        loop:
        for (let item of items) {
            if (someTest(item)) {
                going = false;
                break loop;
            }
            // do something with item
        }
    }

The loop ends if we reach the first item (hence the use of !!from) or if someTest(item) returns true.