Hey everybody — I have good news and bad news.
Good news: I’ve finished porting all the individual import steps to the cron model and now have a mostly working frontend UI (largely unchanged from the previous iteration of the importer) that utilizes it.
As of this evening, the cron model is able to parse, process, and finish importing two test XML files from the core unit tests (
small-export.xml). The test case, which uses exactly the same assertions as the core unit test, passes all 193 assertions. (Update: an errorless import of the wptest.io sample data has been done.)
WordPress cron import in progress
A completed cron import
Bad news: I wanted to tag a version and release a download today, but I’ve decided not to do so due to the unconfirmed stability of the importer. As some astute observers noted last week, storing the temporary data in the options table can blow out caches. Although I’ve attempted to mitigate this (see  and this reference from a few years back on Core Trac), I still need to test this against some real systems before I release it and break your server.
Those who are very interested can always check out the source in Subversion. I will post a comment under this post if a download is made available before my next weekly update.
Although an overhaul of the XML parser, as suggested in the comments on last week’s post, is probably necessary to avoid memory and caching issues, my first priority was to finish the migration of processes to the cron tasks. As soon as I can post a working importer, I will immediately turn my attention to the XML parsing step.